The research, led by Jiraporn Sripinyowanich Jongyingcharoen of King Mongkut’s Institute of Technology Ladkrabang in Thailand together with Pattawee Wutthigarn, Suluh Pambudi, and Ekkapong Cheevitsopon, is the first to apply superheated steam fluidized bed drying to coconut press cake. The team compared this approach head-to-head with conventional hot air fluidized bed drying at three temperatures: 130, 145, and 160 degrees Celsius. The choice of technology matters because coconut press cake is a challenging material. Its small particle size and fibrous, lipid-rich structure make it prone to shrinkage, discoloration, and oil entrapment during drying, while its high moisture content demands aggressive moisture removal to reach a shelf-stable state. The researchers targeted a final moisture content of 0.03 grams of water per gram of dry matter, the level at which water activity drops to roughly 0.75, suitable for long-term storage.

Fluidized bed drying works by blowing a gas upward through a bed of particles fast enough that the particles become suspended and behave like a fluid. This ensures intimate contact between the drying medium and every particle, producing uniform, rapid moisture removal. The critical parameter is the minimum fluidization velocity, the gas speed at which the upward drag on the particles exactly balances their weight. In a clever twist, the team found that superheated steam actually made the cake easier to fluidize than hot air. At 130 degrees Celsius, the minimum fluidization velocity in steam was 3.70 meters per second, well below the 4.65 meters per second needed for hot air, because steam at that temperature is less dense and less viscous than air. As temperature rose, the viscosity of steam increased and its fluidization advantage narrowed, an effect the authors attribute to the competing influences of declining density and rising viscosity on the drag force.

The drying performance results were striking. Superheated steam fluidized bed drying consistently outpaced hot air, and the advantage was most dramatic at the lowest temperature tested. At 130 degrees Celsius, steam drying reached the target moisture in just 9 minutes, half the 18 minutes required with hot air, with a significantly higher average drying rate. Even at 160 degrees Celsius, the fastest condition overall, steam still edged out hot air, finishing in 5.5 minutes versus 6 minutes. The authors explain that superheated steam transfers heat more efficiently and creates an oxygen-limited environment that prevents the surface hardening and crust formation that can trap moisture inside particles. By comparison, conventional hot air oven drying of coconut press cake at 50 to 80 degrees Celsius has previously been reported to take anywhere from 70 to 565 minutes, highlighting the enormous throughput gains that high-temperature fluidization delivers.

Energy consumption told a similarly compelling story. The researchers measured the specific energy consumption, the electrical energy required per kilogram of moisture removed, using a power meter connected to the entire drying system during active drying. For both methods, energy consumption fell as temperature increased, because shorter drying times meant less cumulative energy input. But superheated steam was the clear winner at every temperature. The largest saving appeared at 130 degrees Celsius, where steam drying consumed 4.67 megajoules per kilogram of water removed compared with 8.25 megajoules per kilogram for hot air, a reduction of more than 40 percent. This advantage stems partly from the condensation of steam onto the cooler wet particles at the start of drying, which releases latent heat directly into the material and accelerates moisture transfer, and partly from the superior heat transfer coefficients of steam relative to air.

Quality attributes revealed a genuine trade-off between the two methods. Under the microscope, hot air dried samples showed a compact, dense, shrunken fibrous structure, driven by capillary forces that pull the cellulose-rich matrix together as water leaves. Steam dried samples, in contrast, retained a more open, expanded, porous morphology, apparently because rapid internal vapor generation partially counteracts structural collapse. This difference translated into color: steam dried cake was consistently and significantly whiter than hot air dried cake at every temperature, with the highest whiteness achieved at 160 degrees Celsius, where drying time was shortest. The oxygen-poor steam atmosphere limits oxidative discoloration, and reduced thermal exposure curbs non-enzymatic browning reactions such as the Maillard reaction and caramelization. Notably, steam dried samples also yielded significantly higher extractable oil content, peaking at 34.89 percent at 160 degrees Celsius, likely because their open structure allows better solvent penetration during analysis, whereas the dense hot-air-dried matrix physically traps oil inside.

Interestingly, hot air drying claimed one quality victory of its own. Cake dried with hot air at 160 degrees Celsius exhibited the highest swelling capacity, at 12.37 milliliters per gram of dry matter, and the highest water holding capacity, at 9.74 grams of water per gram of dry matter. The authors suggest that intense thermal exposure under hot air may modify the protein matrix surrounding starch granules and disrupt cell walls, enhancing the material’s ability to absorb and retain water. Water retention capacity, however, showed no significant differences across any treatment, indicating that neither the drying medium nor temperature substantially altered the capillary retention mechanisms within the fibrous matrix. Overall, the hydration properties of the dried press cake matched or exceeded those of commercial dietary fiber sources such as apple, oat, wheat, and pea bran in several respects, underscoring its potential as a functional fiber ingredient.

The microbiological findings may be the most consequential for food safety. Fresh coconut press cake carried an aerobic plate count of 123,000 colony-forming units per gram, along with measurable coliforms, E. coli, and yeasts and molds. Both drying methods dramatically reduced microbial loads, but steam was consistently more lethal at equivalent temperatures. At 160 degrees Celsius, steam drying brought the aerobic plate count down to 2,950 CFU per gram, compared with 10,500 for hot air, and reduced yeast and mold counts to below the detection limit of 25 CFU per gram. Critically, only steam fluidized bed drying at 160 degrees Celsius satisfied every microbiological criterion of the Philippine National Standard for coconut flour, the benchmark the team selected because it explicitly covers coconut residue. E. coli and Salmonella were not detected in any dried sample, though the authors caution that without inoculated challenge tests these results cannot be read as validated pathogen elimination. Prior research lends mechanistic support: microbial death rates in superheated steam can be dramatically faster than in hot air, with documented D-values for E. coli of under 0.10 minutes in steam at 300 degrees Celsius versus 1.12 minutes in air.

To tie the whole dataset together, the researchers ran an exploratory principal component analysis across fourteen process, quality, and safety variables. The analysis revealed that longer drying times and higher energy consumption clustered with higher residual microbial counts, while the steam treatments grouped toward lower microbial loads, greater whiteness, and higher extractable oil content. Hot air drying at 160 degrees Celsius stood apart, aligned with the superior hydration properties. The authors are careful to acknowledge limitations, including the absence of sensors to measure oxygen and steam concentrations in the drying chamber and the lack of direct lipid oxidation measurements, and they frame the multivariate results as descriptive rather than causal. Still, the practical conclusion is clear. For producers seeking maximum water binding in the dried cake, hot air at 160 degrees Celsius remains a defensible choice. But for a combination of speed, energy efficiency, whiteness, oil availability, and regulatory-grade microbial safety, superheated steam fluidized bed drying at 160 degrees Celsius emerged as the standout process, offering tropical coconut industries a credible route to transform a perishable waste stream into a safe, high-value functional food ingredient within minutes rather than hours.

Subject of Research: Comparative evaluation of superheated steam versus hot air fluidized bed drying of coconut press cake for energy efficiency, quality, and microbial safety

Article Title: Integrated evaluation of superheated steam and hot air fluidized bed drying of coconut press cake: Impacts on energy efficiency, product quality, and microbial safety

Article References: Jongyingcharoen, J. S., Wutthigarn, P., Pambudi, S., & Cheevitsopon, E. (2026). Integrated evaluation of superheated steam and hot air fluidized bed drying of coconut press cake: Impacts on energy efficiency, product quality, and microbial safety. Journal of Agriculture and Food Research, 31, Article 103307. https://doi.org/10.1016/j.jafr.2026.103307

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103307

Keywords: coconut press cake, superheated steam drying, fluidized bed drying, food safety, energy efficiency, functional foods, dietary fiber, microbial inactivation, food processing, agro-industrial waste, drying technology, sustainable food

Ara h 1 is no minor player. It makes up 12 to 16 percent of total peanut protein and is recognized by IgE antibodies in 70 to 90 percent of peanut-allergic patients. Of the 19 peanut allergens officially designated by the WHO/IUIS Allergen Nomenclature Sub-Committee, Ara h 1 stands out as a seed storage protein whose three-dimensional shape underpins much of its allergenicity. The research team, led by Yong-Qiang Wang and Ying-Chao Li of Changzhou Vocational Institute of Engineering together with colleagues at Jiangyin People’s Hospital, Yangzhou University and Jiangnan University, set out to test whether high-temperature and high-pressure (HTHP) treatment, essentially the saturated steam conditions of commercial autoclaving and retorting, could reshape that protein enough to blunt its immunoreactivity.

The researchers worked with two systems side by side: purified Ara h 1 and a crude peanut protein extract, so they could compare how the allergen behaves in isolation versus within the complex matrix of a real food. They subjected both to steam treatment at 121 degrees Celsius under 0.1 megapascals of pressure and at 135 degrees Celsius under 0.22 megapascals, for durations ranging from 10 to 60 minutes. These temperatures were chosen deliberately because they correspond to standard commercial sterilization protocols, meaning any findings could translate directly into existing food industry practice rather than requiring novel equipment or processing steps.

The results were striking. After 20 minutes at 135 degrees Celsius, the immunoreactivity of purified Ara h 1 fell to 33.4 percent of the untreated control, and after 60 minutes it dropped to just 16.7 percent. In the crude peanut extract, the effect was even more pronounced: immunoreactivity fell to 25.0 percent and 10.0 percent of control levels after 20 and 60 minutes respectively. The team measured this using competitive ELISA with rabbit polyclonal antibodies raised against the allergen, and confirmed the pattern with Western blotting, which revealed that the intact 65-kilodalton Ara h 1 band progressively disappeared while immunoreactive fragments accumulated at roughly 55, 35, 25 and 15 kilodaltons depending on the treatment and the sample matrix.

Electrophoresis told a story of molecular demolition. Under the harshest conditions, 135 degrees Celsius for 20 minutes or longer, small proteins of 15 kilodaltons or less came to dominate the soluble fraction, constituting approximately 56 to 75 percent of total soluble protein after an hour. Soluble protein content of purified Ara h 1 dropped by about 36 percent after 20 minutes at 135 degrees Celsius before plateauing, suggesting that part of the protein had aggregated into insoluble forms or degraded while the remainder resisted further precipitation. Intriguingly, Ara h 1 appeared less thermally stable within the crude extract than on its own, with the intact 65-kilodalton band vanishing more readily in the mixed protein environment, possibly because interactions with a protein of around 55 kilodaltons promoted its aggregation or altered its degradation pathway.

To see what the treatment actually did to the protein’s architecture, the team turned to atomic force microscopy, circular dichroism spectroscopy and intrinsic fluorescence. Native Ara h 1 appeared under the microscope as uniform spheres roughly 5 nanometers tall. After 20 minutes at 135 degrees Celsius, those spheres had transformed into irregular short rod-like aggregates about 3 nanometers in height, and after an hour at either temperature the protein formed heterogeneous globular fragments only around 2 nanometers tall. The morphology mirrored that of Ara h 1 extracted from roasted peanuts in earlier studies, reinforcing the picture of a protein that refolds into compact, fragmented structures after thermal assault.

The spectroscopic data filled in the molecular details. Circular dichroism in the far-ultraviolet region showed that the native protein, initially composed of 20.9 percent alpha-helix, 24.5 percent beta-sheet, 19.4 percent beta-turn and 36.8 percent random coil, progressively lost beta-sheet and beta-turn content while gaining alpha-helical and disordered structures. Near-ultraviolet circular dichroism, which probes the microenvironments of aromatic amino acids, revealed that ordered tertiary structure containing tyrosine residues was nearly eliminated during the first 10 to 20 minutes of treatment, although longer treatment partially restored the tyrosine packing signal. Intrinsic fluorescence showed a slight red shift in the tryptophan emission maximum after treatments longer than 20 minutes, indicating that buried tryptophan residues were increasingly exposed to the aqueous solvent.

These structural changes matter because they plausibly explain the loss of immunoreactivity. Conformational epitopes, the folded three-dimensional shapes that B lymphocytes and IgE antibodies primarily recognize, depend on higher-order protein structure, so dismantling that structure destroys the shapes antibodies bind. Increased exposure of aromatic residues may also make the protein more vulnerable to digestive enzymes such as gastric protease, which cleave preferentially at aromatic amino acids, potentially reducing the allergen’s ability to survive the gut intact and sensitize the immune system. The rise in random coil and alpha-helix content coupled with reduced beta-sheet structure has previously been associated with diminished allergenic reactivity in other food proteins.

The authors are careful to flag important caveats. Immunoreactivity here was assessed with rabbit IgG as a surrogate, not with human IgE from peanut-allergic patients, so the findings demonstrate structural epitope destruction but do not directly measure clinical allergenicity; residual IgE binding in sensitized individuals could still trigger reactions. The analyses were also restricted to the soluble fraction, leaving the insoluble precipitate, which may retain allergenic potential, uncharacterized. Only two temperatures were tested, and questions about long-term stability, flavor, texture and nutrient content remain open before industrial application. The team recommends follow-up work with human serum-based assays, basophil activation tests, and in vivo models to confirm clinical relevance.

Even with those caveats, the implications are compelling. HTHP processing is already an established sterilization technique, so a food manufacturer could in principle reduce the immunoreactivity of peanut ingredients using equipment and protocols that exist today, without genetic engineering, enzymatic additives or chemical treatments that raise consumer safety concerns. As a step toward hypoallergenic peanut products, the study offers a detailed structure-activity account of exactly how heat and pressure dismantle one of the world’s most consequential food allergens, molecule by molecule, and a roadmap for the clinical validation that must come next.

Subject of Research: Structural modification and immunoreactivity reduction of the peanut allergen Ara h 1 by high-temperature and high-pressure processing

Article Title: Structural modifications and immunoreactivity reduction of peanut allergen Ara h 1 under high-temperature and high-pressure processing

Article References: Wang, Y.-Q., Li, Y.-C., Duan, H.-Y., Zhu, H.-K., Jiang, L., & Qian, H. (2026). Structural modifications and immunoreactivity reduction of peanut allergen Ara h 1 under high-temperature and high-pressure processing. Discover Chemistry, 3(1), Article 542. https://doi.org/10.1007/s44371-026-01004-w

Image Credits: AI Generated

DOI: 10.1007/s44371-026-01004-w

Keywords: peanut allergy, Ara h 1, food allergen, high-pressure processing, immunoreactivity, protein structure, circular dichroism, atomic force microscopy, ELISA, food processing, allergenicity, food safety

The research team harvested fully ripe fruits of three ornamental and culinary Sorbus varieties: Sorbus × arnoldiana ‘Copper Glow’, Sorbus aucuparia ‘Rosina Aurea’, and ×Sorboaronia fallax ‘Titan’, collected from research stations in Lower Silesia, Poland. Each batch was then split across six dehydration routes: conventional convective drying in hot air at 60 °C, freeze-drying under vacuum at −60 °C, vacuum-microwave drying, microwave-convective drying, and two hybrid protocols in which fruits were first pre-dried convectively for three or six hours before being finished in a vacuum-microwave field at reduced power. Every dried sample was then subjected to a battery of ultra-performance liquid chromatography measurements targeting five polyphenol classes, carotenoids, and L-ascorbic acid, alongside three complementary antioxidant assays — ABTS, FRAP, and ORAC — plus colorimetry, water activity analysis, and, in a first for this fruit group, X-ray micro-computed tomography of the fruit interior.

The drying kinetics alone tell a striking story. Convective drying, the industrial workhorse, required roughly 950 minutes — nearly sixteen hours — to bring the berries below ten percent moisture. Freeze-drying took a full 24 hours. Vacuum-microwave drying, by contrast, accomplished the same dehydration in just 34 to 46 minutes, a speed-up of more than twentyfold. The reason lies in the physics of volumetric heating: instead of waiting for heat to conduct slowly from the skin inward, microwave energy is absorbed directly by water dipoles throughout the tissue, generating internal vapor pressure that drives moisture toward the low-pressure chamber surface. The hybrid CPD/VMFD protocols cut total processing time severalfold relative to hot-air drying while keeping the microwave exposure short and gentle. The modified Page model fitted all of the drying curves with coefficients of determination between 0.976 and 0.999, allowing fair comparison across the very different heating regimes.

But speed is worthless if it destroys the chemistry, and here the species-dependence of the results becomes the study’s central finding. No single drying method preserved every quality attribute in every fruit. Freeze-drying generally retained the most bioactive compounds and the highest antioxidant capacity, as expected from its low-temperature sublimation mechanism, but in Sorbus aucuparia ‘Rosina Aurea’ it paradoxically produced the highest water activity of any treatment — likely because the intact, rigid skin left behind by gentle freeze-drying acted as a diffusion barrier that trapped residual vapor inside the fruit. Microwave-assisted methods, which tended to crack the peel, released that moisture more efficiently in this variety, flipping the usual hierarchy.

The vitamin C data are perhaps the most dramatic illustration of how much the response varies by genotype. In ‘Copper Glow’, vacuum-microwave drying actually raised the measured L-ascorbic acid concentration by nearly 35 percent relative to fresh fruit, yielding 326.8 mg per 100 g of dry matter — an outcome plausibly linked to concentrating effects and improved extractability. In ‘Titan’, the same family of microwave treatments was catastrophic: microwave-convective drying erased 98.9 percent of the vitamin C, and even the hybrid methods destroyed more than 86 percent. For that variety, only freeze-drying kept losses to a negligible 1.6 percent. Prolonged convective drying was consistently the worst option for ascorbic acid, cutting it by 25 percent in ‘Copper Glow’, 55 percent in ‘Rosina Aurea’, and a devastating 93.8 percent in ‘Titan’, reflecting the compound’s well-known sensitivity to heat and oxygen over long exposure windows.

Polyphenols followed their own species-specific logic. The dominant fraction in every Sorbus fruit was polymeric procyanidins, ranging from roughly 4,100 to 8,775 mg per 100 g of dry matter depending on variety and treatment, followed by phenolic acids, flavonols, and flavan-3-ol dimers. Anthocyanins were detected exclusively in the dark-red ‘Titan’, and hot-air drying wiped out 74 percent of them, while freeze-drying preserved 98.4 percent. Most intriguingly, in ‘Rosina Aurea’ microwave-based methods increased the measured content of phenolic acids, flavan-3-ols, and flavonols by 50 to 160 percent over fresh fruit. This apparent gain likely reflects a combination of thermal conversion of precursors, Maillard-type chemistry, and microwave-induced disruption of cell walls that releases bound phenolics into the extractable pool — a reminder that ‘content’ in dried plant foods is a moving target shaped by both destruction and liberation.

The computed tomography scans gave the chemical data a physical explanation. Fresh fruits showed a dense, finely porous mesocarp with no internal voids. Freeze-dried berries kept a structure closest to the original, with visible pores from ice sublimation but the pulp still filling the interior. Convective drying produced severe tissue shrinkage and large internal cavities as the flesh contracted, while the microwave treatments carved out extensive voids and frequently cracked the skin, a consequence of rapid internal pressurization. These structural fingerprints mapped cleanly onto the chemical outcomes: berries that retained continuous tissue architecture — especially after freeze-drying — also preserved more vitamin C, carotenoids, and polyphenols, whereas ruptured skins and collapsed tissue presumably opened the door to oxygen, accelerating oxidative degradation of the most labile compounds. Carotenoids told a complementary story, with ‘Titan’ — the richest source at over 7,300 mg per 100 g fresh — keeping 98.4 percent after freeze-drying but losing more than two-thirds under microwave-convective conditions, while ‘Copper Glow’ actually gained about 12 percent after convective drying, consistent with its comparatively intact pulp structure in the CT images.

A principal component analysis pulled the entire dataset together and delivered the study’s clearest takeaway: two components explaining 85.6 percent of the variance separated the fruits primarily by species, not by drying method. ‘Titan’ clustered with carotenoids, anthocyanins, and flavonols; ‘Copper Glow’ aligned with vitamin C, phenolic acids, and antioxidant assays; and ‘Rosina Aurea’ sat apart with its distinctive flavan-3-ol profile. Drying treatment modulated the intensity of each fruit’s signature, but the botanical identity dictated the direction of the response. In practical terms, there is no universal recipe: a processor chasing vitamin C should treat ‘Copper Glow’ and ‘Titan’ completely differently, and pigment preservation demands its own protocol in each case.

The authors are careful to frame the work as preliminary — single-season harvests, three varieties, and no cost or scale-up analysis — but the direction is clear. Freeze-drying remains the gold standard for quality, yet its energy appetite and 24-hour cycle are hard to justify for a niche crop. The hybrid convective pre-drying followed by vacuum-microwave finishing offers a defensible compromise, cutting processing to a fraction of the time while retaining much of the nutritional and functional value, particularly for phenolic-rich products. For a genus of trees that lines European streets and parks largely as ornament, the message is quietly radical: rowan berries are a serious functional-food candidate, and with the right dehydration strategy — chosen species by species — they could graduate from bird food to supermarket shelf. The next step is engineering: optimizing microwave power profiles, quantifying the economics, and proving that what works in a Wrocław laboratory can survive an industrial dryer line.

Subject of Research: Effects of six drying technologies on bioactive compounds, antioxidant activity, color, water activity, and microstructure of three underutilized Sorbus fruit species, assessed by chromatography and X-ray computed tomography.

Article Title: Drying of underutilized Sorbus fruits species: effects on quality attributes, bioactive compounds and microstructure

Article References: Siniawska, M., Lech, K., Masztalerz, K., Bąbelewski, P., & Wojdyło, A. (2026). Drying of underutilized Sorbus fruits species: effects on quality attributes, bioactive compounds and microstructure. Journal of Agriculture and Food Research, 31, Article 103265. https://doi.org/10.1016/j.jafr.2026.103265

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103265

Keywords: Sorbus, rowan, fruit drying, freeze-drying, vacuum-microwave drying, polyphenols, vitamin C, carotenoids, antioxidant activity, computed tomography, food processing, functional foods

The authors frame their work against a backdrop of mounting concern. A 2024 umbrella review in the BMJ concluded that greater dietary exposure to ultra-processed foods is associated with a higher risk of adverse health outcomes across the lifespan, with the evidence for cardiometabolic and mental health effects rated convincing or highly suggestive. A subsequent systematic review of 104 prospective studies found that 92 demonstrated an association between an ultra-processed dietary pattern and increased risk of chronic disease in adults. Ultra-processed foods have also been implicated in significant diet-related environmental impacts, and limiting them has been identified as a strategy to advance both human health and environmental sustainability. For athletes, who often consume large quantities of formulated products, these findings raise uncomfortable questions.

Central to the review is the question of classification. The dominant framework, the NOVA system developed by Monteiro and colleagues, sorts foods into four groups based on the nature, extent and purpose of processing: unprocessed and minimally processed foods, processed culinary ingredients, processed foods, and ultra-processed foods. Sports foods, by virtue of their formulation with protein isolates, maltodextrins, emulsifiers, flavour enhancers and other ingredients rarely found in domestic kitchens, typically fall into the ultra-processed category. Yet NOVA judges foods solely on their degree of processing and additives, not on their nutritional value, performance utility or environmental footprint, a limitation the authors argue is particularly problematic for athletes whose needs differ sharply from those of the general population.

The classification system is not without controversy. The review catalogues numerous categorisation anomalies: plain yoghurt is minimally processed, some fruit yoghurts are merely processed, and flavoured yoghurt is ultra-processed, while homemade fries and certain packaged corn chips can share the same category. Even food and nutrition experts disagree when classifying products using NOVA, and manufacturer reformulations can shift a product between categories over time. Alternative systems such as Siga, which offers finer gradations from unprocessed foods to ultra-processed products with multiple markers of ultra-processing, address some criticisms but have their own gaps. A new formulation and processing food index developed by an international task force may eventually refine the picture, but for now athletes and practitioners must navigate imperfect and sometimes contradictory tools.

On the question of awareness, the review found a striking research void: no published studies have examined athletes’ knowledge or understanding of ultra-processed foods. Evidence from the general population suggests familiarity with the term does not translate into accurate recognition. In a UK study, only 13 percent of participants correctly categorised all ultra-processed foods shown, and confidence in identifying them far outstripped actual ability. Even among dietitians, more than half were unfamiliar with NOVA, and fewer than a quarter correctly classified many grain foods. Given that sports dietitians are well placed to influence athlete food choices, these knowledge gaps matter, the authors argue, because practitioners cannot guide athletes on products they themselves struggle to classify.

What the review did find is a consistent picture of why athletes choose these products. Convenience and performance dominate. Among 1,145 athletes surveyed in Ireland, sensory appeal, food and health awareness and performance were the leading determinants of food choice, while sustainability considerations ranked in the lowest quartile. Ultra-endurance athletes prioritised products that avoid gastrointestinal discomfort, provide energy and can be easily carried and consumed. Australian athletes and exercisers reported improved performance, endurance and recovery as key reasons for using sports foods, with cost and taste the main deterrents. German endurance athletes noted that while everyday foods were generally preferred, sports foods were sometimes more convenient or time-saving during training. Interviews with English Premier League players revealed that upbringing, club culture, coaches, teammates and media all shape dietary practices.

Consumption data, though sparse, suggest frequent use. In an Australian survey, nearly all athletes and exercisers reported consuming sports foods within the previous 12 months, and roughly 70 percent of German-speaking triathletes, cyclists and runners used a combination of commercial sports nutrition products and everyday foods. Studies of European endurance runners, Romanian soccer players and Spanish cyclists and triathletes all documented regular intake of processed and ultra-processed items, though the authors caution that inconsistent classification methods, small samples and questionnaires that capture only narrow food categories make comparisons difficult. Notably, no study has yet quantified ultra-processed food intake as a percentage of total energy intake in athletes, the metric most relevant for assessing health risk.

The review also challenges a cherished assumption of sports nutrition: that a food-first approach automatically reduces ultra-processed intake. When the authors classified the everyday food swaps suggested in Australian Institute of Sport resources using NOVA, they found that each sports food category included replacement items spanning multiple processing categories, including some that are themselves ultra-processed. An Australian analysis of the packaged food supply found that 40 percent of core foods were ultra-processed, meaning that swapping a sports gel for honey or a bar for a muesli bar may not meaningfully change processing exposure. Meanwhile, a systematic review found little or no difference in endurance performance between carbohydrate supplements and ordinary foods such as bananas, raisins or potatoes, and a Spanish case study showed that an ultra-endurance event could be fuelled entirely with sustainable, minimally processed foods, though the practicality of doing so outside controlled settings remains untested.

On health and environmental impacts, the evidence in athletes is thin. Only one study has examined high ultra-processed food consumption and fitness measures in athletes, finding no differences in anthropometrics or cardiovascular fitness among elite basketball players but altered gut microbiota, with confounding from suboptimal carbohydrate and high fat intakes. No studies have linked sports food consumption to health outcomes in athletes or the general population. Yet athletes may carry a larger environmental food footprint than the general population because of higher total energy and protein needs, and data from Turkish elite athletes showed higher greenhouse gas emissions and water footprints strongly tied to red meat and animal protein consumption. The authors call for research into the prevalence and patterns of sports food and ultra-processed food use, their effects on athlete health and performance, and how dietitians can help athletes optimise nutrition strategies that support performance, personal health and planetary health alike.

Subject of Research: Ultra-processed food and sports food use, awareness and impacts among athletes

Article Title: Ultra-processed Foods and Athletes: Current Insights on Classification, Use, Awareness, and Impact—A Narrative Review

Article References: Ultra-processed Foods and Athletes: Current Insights on Classification, Use, Awareness, and Impact—A Narrative Review. (n.d.). https://doi.org/10.1186/s40798-026-01098-7

Image Credits: AI Generated

DOI: 10.1186/s40798-026-01098-7

Keywords: ultra-processed foods, sports foods, athletes, sports nutrition, NOVA classification, planetary health, food-first approach, athlete health, sustainability, dietitians, performance nutrition, food processing

The nutritional case for tartary buckwheat rests on its remarkable phytochemical content. Unlike most cereal grains, tartary buckwheat is exceptionally rich in rutin, a flavonoid glycoside also known as vitamin P, along with quercetin, phenolic acids, and the sulfur-containing compound D-chiro-inositol. These molecules have been associated in prior laboratory and animal studies with antioxidant activity, improved glucose regulation, and reduced lipid accumulation. The catch has always been delivery: rutin is notoriously sensitive to heat, light, and enzymatic degradation, and traditional processing methods for buckwheat tea, which involve prolonged roasting at high temperatures, can strip away a substantial fraction of the very compounds that make the grain medicinally interesting.

The research team behind the new study confronted this trade-off directly. Their goal was to develop an instant tea powder that could be dissolved quickly in hot water, offering the convenience that modern consumers demand, while retaining as much of the native rutin and associated polyphenols as possible. The preparation process described in the paper involves careful control of roasting conditions, extraction parameters, and drying techniques. By optimizing the interplay between temperature, time, and moisture, the researchers were able to strike a balance between the flavor development that roasting imparts and the chemical preservation that milder conditions allow. The result is a powdered product engineered to deliver both sensory appeal and functional potency in a single cup.

Technical characterization of the powder formed a central pillar of the study. The authors report detailed measurements of the rutin content, total phenolic levels, and antioxidant capacity of the finished product, comparing them against conventionally processed tartary buckwheat preparations. These analyses serve two purposes. First, they demonstrate quantitatively that the optimized process succeeds in safeguarding thermolabile flavonoids that would otherwise be lost. Second, they establish a chemical fingerprint that links the product’s composition to its biological activity, a crucial step for any food-derived intervention hoping to make credible health claims. In an era when functional foods face increasing regulatory scrutiny, this kind of rigorous compositional documentation is not merely good practice; it is a prerequisite for the field’s maturation.

With the product’s chemistry established, the study turned to the central question of hypolipidemic effect. Elevated blood lipids, particularly high levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides, remain among the most significant modifiable risk factors for atherosclerotic cardiovascular disease, which continues to lead global mortality statistics. While statin therapy has transformed the treatment landscape, there is enduring interest in dietary interventions that could either complement pharmacological approaches or serve as preventive strategies for populations with mildly elevated lipid levels. Food-based interventions occupy a unique position in this space because they combine accessibility, cultural acceptability, and a favorable safety profile.

The hypolipidemic evaluation reported in the paper provides evidence that consumption of the instant tartary buckwheat tea powder can shift lipid parameters in a favorable direction. The authors attribute this effect primarily to the rutin and other polyphenols preserved by their processing strategy, molecules that are understood to interfere with lipid absorption, modulate hepatic lipid metabolism, and influence the activity of enzymes central to cholesterol homeostasis. Rutin and its metabolites have been shown in experimental systems to inhibit pancreatic lipase, reduce cholesterol micellar solubility in the intestine, and upregulate the expression of cholesterol efflux transporters. By documenting that a realistic, drinkable food product retains and delivers these bioactives, the study bridges a persistent gap between laboratory evidence of flavonoid activity and the practical question of whether a consumer product can achieve measurable benefit.

What distinguishes the work from much of the functional food literature is its integrated design. Rather than treating processing science and biological evaluation as separate silos, the researchers pursued both in a single study, creating a closed loop from raw grain to finished effect. This approach matters because the bioactive content of a food ingredient is only as good as the processing pipeline that preserves it. Many promising candidates have faltered at the commercialization stage precisely because scaled-up manufacturing destroyed the compounds responsible for the observed health effects. By demonstrating that their instant powder maintains rutin integrity while achieving hypolipidemic outcomes, the team has produced a template that other grain-based functional food developers may well follow.

The broader implications extend to public health strategy, particularly in regions where tartary buckwheat is already grown. Buckwheat cultivation thrives in cool, high-altitude environments with thin soils, making it an economically important crop for farmers in southwest China and other marginal agricultural zones. A validated, convenient, health-promoting product built on this crop could raise its commercial value, support rural livelihoods, and simultaneously offer consumers an evidence-based beverage option. There is also a sustainability dimension to consider: buckwheat generally requires fewer agricultural inputs than major cereals, and expanding its use fits neatly into discussions about diversifying the global food system beyond a narrow set of staple crops.

Cautious readers will note the usual caveats that accompany early-stage food science. The magnitude of lipid changes, the appropriate consumption dose, the duration of use required for full effect, and the transferability of results across different populations all warrant further investigation, ideally through well-designed human dietary trials. The authors’ findings establish a strong mechanistic and product-development foundation, but the path from a promising instant tea powder to a clinically endorsed dietary recommendation runs through the familiar gauntlet of larger cohorts, longer follow-up periods, and independent replication. Nonetheless, the study’s dual achievement, a processing innovation that protects fragile bioactives and evidence that the resulting product acts on a major cardiovascular risk factor, gives the field concrete reasons for optimism.

For now, the image of a steaming cup of tartary buckwheat tea, once a regional tradition, has been reframed as a subject of rigorous food science. The new research suggests that with the right preparation technology, convenience and functionality need not be adversaries. As consumers grow increasingly sophisticated about the relationship between diet and chronic disease, and as researchers continue to unlock the chemistry of underutilized grains, products like this instant powder may come to occupy a meaningful place in everyday cardiometabolic prevention. The bitter grain of the mountains, it turns out, may have been storing its most valuable compounds all along, waiting for the science to catch up with the tradition.

Subject of Research: Preparation and hypolipidemic effect of instant tartary buckwheat tea powder

Article Title: Preparation and hypolipidemic effect of instant tartary buckwheat tea powder

Article References: Preparation and hypolipidemic effect of instant tartary buckwheat tea powder. (n.d.). https://doi.org/10.1038/s41538-026-01135-5

Image Credits: AI Generated

DOI: 10.1038/s41538-026-01135-5

Keywords: tartary buckwheat, instant tea powder, hypolipidemic effect, rutin, flavonoids, blood lipids, functional foods, cholesterol, food processing, cardiovascular health, polyphenols, npj Food

Flavonoids themselves are a vast family of plant secondary metabolites built on a fifteen-carbon skeleton of two aromatic rings joined by a three-carbon bridge. Depending on the oxidation state of that central ring, they divide into familiar subclasses such as flavones, flavonols, flavanones, and anthocyanidins. Plants rarely leave these backbones bare; they decorate them with hydroxyl, methyl, and sugar groups, and those decorations govern nearly everything: solubility, stability, color, taste, and biological activity. Glycosylation is the most common decoration of all, and the position and nature of the sugar attachment turns out to matter enormously.

The distinction between O- and C-glycosides is chemical but consequential. In O-glycosides, the sugar hangs from the flavonoid through an oxygen atom, forming a bond that human and microbial enzymes in the small intestine can hydrolyze readily. That cleavage releases the aglycone—the bare flavonoid—which can then be absorbed. C-glycosides, by contrast, form a direct carbon–carbon bond between the sugar and the flavonoid skeleton, typically at the C-6 or C-8 position of the A-ring. That bond is dramatically more stable: it resists acidic conditions in the stomach, resists the human enzymes that strip sugars from O-glycosides, and survives much of the journey through the digestive tract intact.

For years, this resilience was interpreted as bad news for bioavailability. If a compound cannot be de-glycosylated, the reasoning went, it cannot release its active aglycone, and so C-glycosides such as vitexin, isovitexin, orientin, homoorientin, and the iconic apigenin derivatives of chamomile and buckwheat must be poorly absorbed and therefore biologically inert. Recent work has complicated that picture. Studies with isolated human gut microbiota and animal models show that colonic bacteria, particularly certain Bacteroides and Eubacterium strains, possess C-glycoside-cleaving enzymes capable of breaking the resistant bond slowly, releasing aglycones and a cascade of smaller phenolic metabolites deeper in the intestine, where they can act locally on the gut lining and enter the portal circulation.

The review’s treatment of structure–activity relationships builds on this metabolic nuance. Biological activity in flavonoids correlates with recognizable structural features: the catechol group on the B-ring drives antioxidant and metal-chelating activity, a planar chromone core supports enzyme binding, and specific hydroxylation patterns govern interactions with signaling proteins. Glycosylation at the A-ring modifies these effects indirectly but measurably, altering solubility, membrane affinity, and the compound’s ability to reach intracellular targets. C-glycosylation, by locking the sugar permanently onto the skeleton, produces molecules whose activity profiles differ from those of their O-glycosylated counterparts—not better or worse in absolute terms, but differently distributed between the gut lumen, the bloodstream, and the target tissues.

Where C-glycosides shine is in stability, and stability is the currency of food formulation. O-glycosides and free aglycones are notoriously fragile: they degrade under heat, oxidize in the presence of oxygen and light, and lose activity during pasteurization, baking, and storage. C-glycosides, anchored by their carbon–carbon bond, tolerate far harsher processing. Vitexin and isovitexin in mung bean and buckwheat survive boiling and extrusion with comparatively modest losses. Orientin and its isomers in millet and bamboo leaves persist through drying and fermentation. For food manufacturers seeking to add functional ingredients without sacrificing shelf life, this processing robustness is a genuine advantage over more celebrated but more delicate polyphenols.

The food sources of these compounds are worth cataloguing because many are staples rather than supplements. Buckwheat is arguably the flagship: its groats and hulls are rich in vitexin and isovitexin derivatives, and traditional buckwheat products across East Asia and Eastern Europe deliver measurable daily doses. Millets, particularly foxtail and proso varieties, contribute orientin and homoorientin. Mung bean, a protein staple across South and Southeast Asia, is one of the densest vitexin sources in any human diet. Date palm pollen, swertia herbs, passion fruit by-products, fenugreek, jujube, and several medicinal plants used in traditional teas round out the list. Because these sources are often underutilized crops or agricultural by-products, the review positions C-glycosides as an opportunity to extract added value from material streams that today carry little market premium.

Analysis techniques for these molecules have matured considerably. Because C-glycosides resist the acid hydrolysis that food chemists traditionally used to quantify flavonoid content, older analytical protocols systematically underestimated them. Modern high-resolution liquid chromatography–mass spectrometry, with fragmentation patterns that distinguish 6-C from 8-C isomers, has revealed that many plant foods carry substantially more C-glycoside content than previously recognized. Nuclear magnetic resonance remains the definitive tool for assigning the exact carbon–carbon linkage position, but diagnostic mass-spectrometric signatures now allow rapid screening of breeding lines and processed products, opening the door to quality control and authenticity testing for functional foods built around these compounds.

On the application side, the review identifies several converging opportunities. In functional beverages, the stability of C-glycosides against pasteurization makes them plausible candidates for standardized polyphenol fortification. In bakery and extruded snack products, their thermal tolerance means they survive the processing that destroys anthocyanins and most aglycones. In encapsulation and delivery systems, their solubility and resistance to gastric degradation make them well suited to colon-targeted release strategies, where bacterial C-glycosidase activity provides a built-in triggering mechanism. And in the growing market for plant-based proteins, crops such as buckwheat and mung bean carry their flavonoid payload alongside the protein, offering clean-label fortification without added extracts.

The health claims remain, appropriately, cautious. Evidence from cell culture and animal studies points to anti-inflammatory, antioxidant, antidiabetic, and neuroprotective effects for specific C-glycosides, with vitexin and orientin among the most studied. But human intervention trials are scarce, and the review is explicit that translating structure–activity relationships from laboratory models to dietary benefit requires dosing studies, metabolite identification in human subjects, and a better understanding of inter-individual variation in gut microbiota composition. What the review does establish is the framework: because the C-glycosidic bond dictates where and when these compounds are activated, structure determines not just potency but delivery, and any future clinical work must account for that metabolic choreography.

The larger significance of the review may lie in how it reframes an old debate. For decades, bioavailability was treated as a gatekeeper metric: compounds that were poorly absorbed were dismissed. But the gut microbiota era has changed the question. A compound that survives intact until the colon and is then transformed into active metabolites by resident bacteria is not poorly bioavailable—it is precisely targeted. Flavonoid C-glycosides, with their indigestible sugar bond and their abundance in underexploited staple crops, may be one of the clearest examples of this shift in thinking, and the food industry’s ability to harness them will depend on marrying the structure–activity knowledge summarized in this review with the practical realities of processing, formulation, and clinical validation.

Subject of Research: Structure–activity relationships of flavonoid C-glycosides and their applications in food science and nutrition

Article Title: Flavonoid C-glycosides: from structure-activity relationships to food applications

Article References: Wu, Z., Shi, D., Wang, Y., & Zeng, S. (2026). Flavonoid C-glycosides: from structure-activity relationships to food applications. npj Science of Food. https://doi.org/10.1038/s41538-026-01141-7

Image Credits: AI Generated

DOI: 10.1038/s41538-026-01141-7

Keywords: flavonoid C-glycosides, structure-activity relationships, vitexin, orientin, buckwheat, gut microbiota, bioavailability, functional foods, food chemistry, polyphenols, mung bean, food processing

The grain’s biology explains much of its chemical wealth. A sorghum caryopsis consists of three layers: the pericarp or bran, the endosperm, and the germ, with the endosperm making up about 84 percent of the grain by weight. Crucially, the phenolic compounds are concentrated in the outer layers, precisely the fractions that milling often discards or diverts to animal feed. The color of the pericarp, which ranges from white and yellow to red, brown, purple, and black, offers a rough visual guide to phenolic density. Pigmented red, brown, and black varieties generally carry far richer phenolic profiles than white types, with black sorghums accumulating exceptionally high levels of 3-deoxyanthocyanidins when exposed to sunlight. But color is an imperfect predictor. The presence of condensed tannins depends on dominant B1 and B2 genes that control the development of a pigmented testa layer, meaning some red grains lack tannins entirely while genetics can outweigh appearance altogether.

Nutritionally, the review compiles striking differences among color variants. Carbohydrate content reaches up to 80 percent of the dry grain, with protein typically between 8 and 12 percent, though red and yellow types can exceed 23 percent. White sorghums tend to offer the most starch, with amylose levels reaching 40 percent, a feature that supports resistant starch formation and low glycemic responses. Pigmented types trade some starch energy for fiber, with black sorghum reaching crude fiber contents of nearly 9 percent, and they deliver substantially more iron, zinc, and magnesium than white counterparts. Potassium is the dominant mineral across all types, with black cultivars containing up to 3,566 milligrams per 100 grams, and the consistently high potassium-to-sodium ratio positions sorghum as a dietary strategy for managing hypertension. Like most cereals, sorghum is limited in lysine, but its fatty acid profile is dominated by heart-friendlier oleic and linoleic acids, which together with palmitic acid account for roughly 90 percent of the oil fraction.

The review’s most detailed analysis concerns the phenolic compounds themselves, mapping more than 110 distinct chemicals identified through advanced HPLC-DAD-ESI-QTOF-MS/MS profiling. Ferulic acid emerges as the undisputed leader, reported in every quantitative study examined and frequently accounting for more than 60 percent of total phenolic acids, mostly in bound form attached to cell wall polysaccharides. Gallic, chlorogenic, protocatechuic, caffeic, and p-coumaric acids round out the major phenolic acids. Among flavonoids, luteolin, apigenin, taxifolin, and naringenin appear most consistently, while the signature 3-deoxyanthocyanidins, luteolinidin and apigeninidin, define the pigmented cultivars. These rare pigments lack a hydroxyl group at the C-3 position of conventional anthocyanins, a small structural difference that confers remarkable stability against pH changes, heat, and bleaching agents such as ascorbic acid and sulfites. Total phenolic content varies more than tenfold between genotypes, from around 0.24 milligrams of gallic acid equivalents per gram in white grains to 11.5 in black cultivars, and antioxidant capacity measured by DPPH, ABTS, and FRAP assays tracks this variation closely.

The health implications documented across hundreds of studies are broad and mechanistically detailed. Sorghum phenolics neutralize reactive oxygen species directly while also upregulating the body’s own antioxidant defenses, increasing the activities of superoxide dismutase, catalase, and glutathione peroxidase in animal models. For metabolic disease, condensed tannins and flavonoids act as competitive inhibitors of alpha-glucosidase and alpha-amylase, in some cases exceeding the inhibitory potency of the antidiabetic drug acarbose, thereby slowing starch digestion and blunting postprandial glucose spikes. Compounds such as taxifolin activate AMPK and Akt signaling to boost glucose uptake in muscle cells, and sorghum extracts inhibit the formation of advanced glycation end products that drive diabetic complications. Anti-inflammatory effects operate largely through suppression of the NF-kappa B pathway, with molecular docking studies showing that apigeninidin and luteolinidin bind directly to critical cysteine residues in the NF-kappa B p65 subunit. Black sorghum extracts additionally protect vascular endothelium by downregulating NOX4 and upregulating nitric oxide synthase and heme oxygenase-1.

Perhaps most striking is the evidence that sorghum phenolics reshape the gut ecosystem. Because many phenolic acids are covalently bound to fiber, they survive upper digestion and reach the colon, where gut microbes release them and ferment them into short-chain fatty acids such as acetate, propionate, and butyrate. Diets rich in sorghum polyphenols increase beneficial genera including Akkermansia, Lactobacillus, Bifidobacterium, and Roseburia, while suppressing potentially harmful taxa such as Proteobacteria. The enrichment of Akkermansia is particularly noteworthy given its association with improved insulin sensitivity and metabolic health. Sorghum phenolics also strengthen the intestinal barrier by inducing tight junction proteins, raise villus height and goblet cell numbers in experimental models, and reduce colonic inflammation in chemically induced colitis. Early research even points toward neuroprotection, with sorghum extracts showing acetylcholinesterase inhibition and interference with amyloid-beta aggregation, though the authors caution that such findings remain confined to laboratory and preclinical settings.

The same chemistry that delivers benefits can also work against nutrition. Condensed tannins bind proline-rich kafirin storage proteins into complexes resistant to digestive enzymes, reducing protein digestibility, and catechol- and galloyl-containing tannins in brown sorghum form poorly absorbable complexes with iron in a dose-dependent manner. The review emphasizes that processing is the decisive lever for tipping this balance. Germination roughly doubles total phenolic content within 72 hours while cutting tannins by up to 38 percent and phytic acid by about 20 percent. Lactic acid fermentation releases bound phenolics through microbial esterases and glucosidases, raising antioxidant activity by up to 46 percent while degrading antinutrients. Extrusion cooking reduces tannins by 44 percent in red varieties even as total phenolics decline, and nixtamalization with lime slashes tannin content by as much as 82 percent. Remarkably, dry-heat treatments such as roasting and microwave heating often increase measurable phenolics and antioxidant activity, apparently by liberating bound compounds from the cell wall matrix.

Industrial applications are already emerging. White sorghum extract eliminated Campylobacter jejuni from inoculated chicken fillets within as little as six days while improving sensory scores, and tannin-rich sorghum combined with cowpea protein produces plant-based burgers with more protein, iron, and zinc and a firmer, meat-like bite. Greek yogurt fortified with 4 percent sorghum flour doubled its antioxidant capacity, and fermented sorghum beverages showed 57 percent inhibition of ACE-I, relevant to blood pressure control. Sorghum grain waste has been upcycled into biodegradable packaging films that extend the shelf life of fresh-cut apples by preventing browning and microbial growth. Meanwhile, the 3-deoxyanthocyanidins are positioning themselves as a natural colorant of unusual industrial value: their solutions retain 80 to 90 percent of their color after two hours at 95 degrees Celsius across the pH range of most foods, and they survive sterilization conditions that destroy ordinary anthocyanins.

The review’s authors, an Indonesian team led by Miftahurrahmi and colleagues working under the RIIM LPDP grant and the National Research and Innovation Agency, close with a research agenda that calls for randomized human clinical trials to validate the largely in vitro health evidence, standardized analytical protocols to make studies comparable, breeding programs that use genomic markers to stack beneficial phenolic traits, and scalable green extraction technologies such as ultrasound, microwave, and subcritical water methods that cut solvent use and processing time dramatically. They also highlight an underexplored frontier: phenolic-rich bran fractions that are currently diverted to animal feed could be valorized as functional food ingredients, a shift with particular relevance for Indonesia’s diverse sorghum cultivars and its push toward food diversification. As climate pressures intensify and consumers seek gluten-free, nutrient-dense alternatives, the humble grain once dismissed as birdseed may prove to be one of agriculture’s most quietly powerful assets.

Subject of Research: Phenolic compounds in sorghum grains, their chemistry, health effects, processing impacts, and applications in functional foods.

Article Title: Sorghum phenolic compounds: Chemistry, health benefits, processing effects, and applications in functional foods

Article References: Miftahurrahmi, Antarlina, S. S., Ginting, E., Khamidah, A., Purwani, E. Y., Sihono, Ismail, N., Yustina, I., Ambarsari, I., & Fauziah, L. (2026). Sorghum phenolic compounds: Chemistry, health benefits, processing effects, and applications in functional foods. Journal of Agriculture and Food Research, 31, Article 103269. https://doi.org/10.1016/j.jafr.2026.103269

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103269

Keywords: sorghum, phenolic compounds, 3-deoxyanthocyanidins, condensed tannins, antioxidants, functional foods, gluten-free grains, food processing, fermentation, natural food colorants, gut microbiota, food security

Polysaccharides are long chains of sugar units that plants deploy for energy storage, structural support, and defense. When consumed, they act largely as dietary fiber: resistant to digestion in the upper gastrointestinal tract but accessible to the trillions of microbes that colonize the colon. There, gut bacteria ferment these chains into short-chain fatty acids such as acetate, propionate, and butyrate, compounds with well-documented roles in maintaining the intestinal barrier, modulating inflammation, and influencing metabolism. Because of this, the molecular architecture of a fruit polysaccharide—its monosaccharide composition, molecular weight, glycosidic linkages, and degree of branching—directly shapes its nutritional and functional value.

The research team set out to determine whether processing changes this architecture. Sun-drying, the most widespread low-cost preservation method in rural agricultural communities, exposes fruit to ultraviolet radiation, heat, oxygen, and enzymatic activity over days or weeks. Steaming, by contrast, is a rapid, moist-heat treatment typically used to soften tissue before consumption. These treatments impose very different chemical stresses, and the study investigated how each one propagates through to the final polysaccharide extract.

Using a suite of analytical techniques standard in carbohydrate chemistry, the researchers profiled polysaccharides extracted from fresh, sun-dried, and steamed fruit. Molecular weight distribution analyses revealed that processing measurably shifted the size of the polysaccharide populations, with thermal exposure capable of depolymerizing large chains into smaller fragments or, conversely, promoting associations among chains. Monosaccharide composition analysis and linkage determination indicated that the proportions of constituent sugars—typically including galacturonic acid, arabinose, galactose, rhamnose, and glucose in pectic and hemicellulosic fractions—were sensitive to the treatment applied. Spectroscopic characterization supported these observations, showing changes in functional group signatures consistent with altered branching or side-chain content.

These structural differences were not merely academic. The physicochemical properties of the polysaccharides—solubility, water-holding behavior, viscosity, and thermal characteristics—varied according to processing method. Such properties matter in practice: they govern mouthfeel and texture in foods, determine how fiber behaves during digestion and transit, and influence the accessibility of the polysaccharide backbone to bacterial enzymes in the gut. A highly branched, high-molecular-weight pectin does not interact with the intestinal environment in the same way as a degraded, low-molecular-weight fraction, and the study documented these divergences in detail.

The most consequential findings concerned gut-related function. In experiments simulating gastrointestinal conditions and gut microbial fermentation, polysaccharides from differently processed fruits displayed distinct fermentation profiles, with differences in the production of short-chain fatty acids and in the support of bacterial growth. This indicates that the health-relevant behavior of a fruit’s fiber fraction can be tuned—perhaps unintentionally—by the way the fruit is handled after harvest. For a crop like Ehretia macrophylla, whose fruit is consumed or used in folk preparations in processed form, the implication is that processing choices carry nutritional weight, not just sensory weight.

The work sits within a broader movement in food science to treat processing as a form of ingredient design. Previous studies have shown that drying, fermentation, extrusion, and heat treatments can each reshape the prebiotic potential of plant polysaccharides from sources as varied as apples, Goji berries, seaweeds, and medicinal mushrooms. What distinguishes the present study is its systematic side-by-side comparison of two traditional methods applied to the same raw material, allowing the authors to attribute differences specifically to the processing route rather than to raw material variability. This design strengthens the case that traditional knowledge and modern analytical chemistry can be productively combined.

For consumers and producers, the study offers practical perspective. Sun-drying remains indispensable in regions lacking cold chains, and steaming is deeply embedded in culinary practice; neither result suggests these methods should be abandoned. Instead, the research points toward optimizing conditions—drying duration, temperature, steam exposure time—to preserve or even enhance the structural features associated with beneficial fermentation. For food formulators, it suggests that process history should be considered when polysaccharide extracts are used as functional ingredients, since the same botanical source can yield extracts with different performance depending on pretreatment.

For scientists, the study raises productive questions. How do processing-induced structural changes translate to outcomes in vivo, in animal models or human trials? Can controlled thermal treatment be used deliberately to tailor prebiotic fibers? And how generalizable are these findings across other fruit polysaccharides, whose architectures differ substantially? Answering these questions will require coupling the kind of careful structural characterization demonstrated here with microbiome sequencing and metabolomic readouts. In the meantime, the message is clear: the road from orchard to gut microbiome is chemically long, and every step—including how the fruit is dried or cooked—leaves a trace on the fibers that feed our microbial partners.

Subject of Research: Effects of sun-drying and steaming on the structure, physicochemical properties, and gut-related functions of Ehretia macrophylla fruit polysaccharides

Article Title: Effects of sun-drying and steaming on Ehretia macrophylla Wall. (EMW) fruit polysaccharides: structure, physicochemical properties and gut-related functions

Article References: Mo, L., Li, H., Yu, Y., Li, J., Zhang, T., Zheng, S., Huang, D., & Zhao, C. (2026). Effects of sun-drying and steaming on Ehretia macrophylla Wall. (EMW) fruit polysaccharides: structure, physicochemical properties and gut-related functions. npj Science of Food. https://doi.org/10.1038/s41538-026-01144-4

Image Credits: AI Generated

DOI: 10.1038/s41538-026-01144-4

Keywords: Ehretia macrophylla, polysaccharides, sun-drying, steaming, food processing, dietary fiber, gut microbiota, short-chain fatty acids, prebiotics, food science, physicochemical properties, carbohydrate structure

The urgency behind the analysis is rooted in sobering global statistics. The 2023 Global Hunger Index reports a moderate score of 18.3, with undernourishment climbing to 735 million people worldwide. Paradoxically, much of this suffering stems not from a lack of calories but from diets heavy in energy yet devoid of essential nutrients, producing widespread malnutrition and micronutrient deficiencies. Of the roughly 374,000 plant species known to science, more than 50,000 are edible, yet only 15 crops supply 90 percent of humanity’s food energy. India alone hosts 8 percent of the world’s plant species, including 1,403 wild edible plants, but the overwhelming dominance of a handful of cereals has left agricultural systems dangerously narrow. Reviving underexploited crops, the authors argue, is essential to achieving the United Nations’ Zero Hunger goal by 2030, and horse gram stands out as a particularly strong candidate for that revival.

Horse gram is a botanical survivor. The genus name Macrotyloma derives from Greek words meaning “larger knob” and “margin,” a reference to the knobby appearance of its pods. The plant is a short, bushy annual or perennial reaching just 30 to 40 centimeters in height, with a weak, slender stem that spreads rather than stands. It grows happily in clay loam, deep red loam, and black cotton soils, prefers annual temperatures between 18 and 27 degrees Celsius, tolerates extremes up to 40 degrees, and can be cultivated at elevations above 1,800 meters on marginal soils receiving as little as 380 millimeters of annual rainfall. Cultivated across subtropical, temperate, and semi-arid regions of Africa, Southeast Asia, and Australia for food and fodder, the crop also yields residues and straw that serve as green manure, animal feed, and fuel. Its very name in many rural communities—”poor man’s pulse”—reflects how deeply it is tied to the populations most vulnerable to food insecurity.

Nutritionally, the crop is remarkable. Carbohydrates constitute 51.9 to 60.9 percent of whole seeds and up to 66.4 percent of dehulled seeds, including soluble sugars such as glucose, fructose, sucrose, and maltose. Raw seeds contain 22 to 44 percent starch, of which about 85 percent is digestible. Protein content ranges from 18.5 to 31.2 percent depending on cultivar, with a wild relative, Macrotyloma sargarhwalensis, reaching an exceptional 38.4 percent. Globulins make up 60 to 90 percent of total seed protein, complemented by glutelins and albumins. Critically for cereal-based diets, horse gram is rich in lysine—0.52 grams per gram of nitrogen, exceeding black gram and pigeon pea—and surpasses kidney beans in threonine, leucine, isoleucine, phenylalanine, valine, and histidine. This makes it an excellent biological complement to rice and wheat, whose proteins lack sufficient lysine. For a world increasingly searching for sustainable plant-based protein sources, these amino acid profiles carry genuine weight.

The legume’s lipid and micronutrient content is equally impressive. Crude fat ranges from 0.6 to 2.6 percent, but the fatty acid composition is skewed toward the healthy side: 72.5 percent unsaturated, dominated by linoleic, oleic, and linolenic acids. Total dietary fiber reaches 28.8 percent in seeds, overwhelmingly insoluble, existing as beta-glucan, pectin, hemicellulose, and cellulose—components associated with reduced risks of colon cancer, heart disease, gallstones, and diabetes. Seeds also deliver an exceptional mineral load, including calcium, iron, zinc, magnesium, phosphorus, molybdenum, and potassium, while the leaves contain about 4.5 percent minerals, higher than most common vegetables. Vitamins such as niacin, riboflavin, thiamine, pyridoxine, tocopherol, pantothenic acid, and folic acid round out the profile; deficiencies of these compounds cause diseases ranging from night blindness to beriberi. Beyond macronutrients, horse gram is loaded with phytochemicals: p-coumaric acid and p-hydroxybenzoic acid among the phenolics, quercetin, myricetin, and kaempferol among the flavonoids, and the isoflavonoids daidzein and genistein in the embryonic axes, with tannin concentrations of 763.7 to 895.9 milligrams per 100 grams exceeding those of most other legumes.

Yet the same chemistry that makes horse gram a nutritional treasure also constrains it. The seeds harbor what food scientists call nutrient-limiting compounds—phytic acid at 10.2 milligrams per gram of flour, polyphenols, oligosaccharides, and trypsin inhibitors measured at roughly 9,246 trypsin units inhibited per gram. Phytates, tannins, and oxalic acid chelate iron and calcium into insoluble salts that the gut cannot absorb, undermining the crop’s mineral richness. Trypsin inhibitors, unusually abundant in horse gram, block protein digestion, while α-galactosidic oligosaccharides such as verbascose, stachyose, and raffinose ferment in the colon to cause flatulence and discomfort. Lectins, concentrated in the seeds but also present in roots, stems, and leaves, can interact with immune cells and erythrocytes, potentially triggering intestinal damage and nutritional anemia. Add to this a short shelf life caused by pest infestation and limited consumer awareness, and the reasons for the crop’s commercial neglect become clear. Its consumption today remains largely confined to rural farming communities and low-income populations, a fate the review’s authors are determined to reverse.

The encouraging news is that simple, traditional processing techniques can disarm most of these antinutritional factors. Soaking seeds for 12 to 24 hours lowers trypsin inhibitors, phytic acid, and tannins while increasing the availability of manganese, zinc, copper, and iron. Germination—a rapid, low-cost method—activates enzymes that hydrolyze starches, fats, and proteins, breaking down trypsin inhibitors and boosting protein content. Dehulling removes hull-bound oxalic acid, phytates, and tannins while raising protein, lipid, and sugar concentrations, and when combined with germination acts synergistically. Fermentation is even more dramatic: a 48-hour treatment with lactic acid bacteria cuts phytate by 69.5 percent, oxalate by 66.8 percent, and tannins by 69.4 percent, as microbial phytase degrades the antinutrient at low pH. Roasting dried seeds at 160 degrees Celsius for ten minutes reduces tannins by 28 percent, flavonoids by 48.7 percent, and phytates by more than 22 percent through thermal denaturation. These are kitchen-scale interventions, requiring no exotic technology, meaning the path to better horse gram nutrition runs directly through traditional culinary practice.

Beyond the kitchen, the review highlights the economic dimension of reviving the crop. Value addition—the transformation of raw commodities into branded, shelf-stable, marketable products—can extend availability year-round, reduce postharvest losses, strengthen off-farm employment, and promote technology transfer in rural economies. Companies have already developed a range of horse gram-based foods, including instant dosa mixes, high-fiber biscuits fortified with germinated horse gram flour, ready-to-cook idly mixes, bread, cookies, ready-to-eat snacks, milk beverages, and flatbreads. Biofortification strategies could further enhance the crop’s protein and phytochemical content, positioning it within the rapidly growing plant-based food market. The authors argue that quantifying the difference between raw material costs and processed product returns will be key to attracting investment and building the market infrastructure the crop currently lacks.

Significant scientific gaps remain before horse gram can achieve its potential. Existing studies often suffer from limited germplasm representation, small sample sizes, and inconsistent analytical methodologies that make cross-study comparisons difficult. The influence of environmental and agronomic factors on nutrient composition is poorly understood, and many claimed health benefits lack mechanistic or clinical validation. The review calls for genome-wide association studies to identify cultivars with lower antinutrient loads and higher protein digestibility, alongside breeding programs aimed at climate resilience under rising temperatures and declining precipitation. Standardized nutritional profiling, shelf-life and storage research, industrial-scale processing feasibility, and sensory-based consumer acceptance studies are all on the priority list. If those research investments materialize, the authors contend, horse gram’s inherent resilience, exceptional nutritional chemistry, and compatibility with low-input agriculture could make it a cornerstone of nutrition-sensitive food systems—proof that the crops we abandoned on the road to modern agriculture may be exactly the ones we need to reclaim.

Subject of Research: The nutritional profile, processing methods, and sustainable agriculture potential of the underutilized legume crop horse gram (Macrotyloma uniflorum).

Article Title: Horse gram: an under-utilized nutrient-rich legume crop as a potential candidate for sustainable agriculture

Article References: Sharma, A., Pant, M., Rawat, A., Rawat, R., Bisht, P., & Kumar, S. (2026). Horse gram: an under-utilized nutrient-rich legume crop as a potential candidate for sustainable agriculture. BMC Agriculture, 2(1), Article 26. https://doi.org/10.1186/s44399-026-00050-0

Image Credits: AI Generated

DOI: 10.1186/s44399-026-00050-0

Keywords: horse gram, Macrotyloma uniflorum, sustainable agriculture, food security, malnutrition, plant protein, antinutritional factors, food processing, biofortification, drought tolerance, value addition, zero hunger