The research team, led by Prachand Neupane and colleagues, set out to test whether essential oils could replace conventional preservatives such as Bavistin and calcium chloride, which are widely used to extend postharvest life but carry residual toxicity concerns. Essential oils have attracted growing scientific interest because of their antioxidant, antifungal, and antibacterial properties, their low mammalian toxicity, and their biodegradability. Earlier in vitro work has shown that lemongrass oil at concentrations from 25 to 500 ppm suppresses colony formation by major tomato spoilage fungi, including Colletotrichum coccodes, Botrytis cinerea, Cladosporium herbarum, Rhizopus stolonifer, and Aspergillus niger.

The experiment used the Srijana tomato variety, a popular hybrid developed by Nepal’s Horticulture Research Division that farmers favor for its adaptability to off-season cultivation and its market appeal. Fruits were harvested at the light red stage from a farm in Harisiddhi, Lalitpur, in late November 2021 and transported to the Central Lab at Paklihawa. After cleaning, manual grading, and visual sorting to ensure uniform size, color, and quality, samples were placed in 2.8-liter plastic containers holding 21 tomatoes each.

Seven treatments were arranged in a completely randomized design with three replications. Four groups received lemongrass essential oil vapor at concentrations of 50, 100, 150, and 200 ppm, sealed under aluminum foil for eight hours. A fifth group was dipped in 1 percent calcium chloride solution and a sixth in a 100 percent extract of Justicia adhatoda, a medicinal plant known locally as Asuro, for 30 minutes each. The seventh group served as an untreated control. The lowest oil concentration was chosen to establish the minimum effective dose, while the highest was intended to reveal any toxic effects during storage.

Over 14 days, the researchers measured physical attributes—weight loss and firmness—and chemical attributes including pH, total soluble solids, titratable acidity, and vitamin C content, sampling every two days. Juice extracted from 20-gram slices was diluted and centrifuged at 10,000 rpm before analysis. Total soluble solids were read with a digital refractometer, acidity was determined by titration with 0.1 N sodium hydroxide, and vitamin C was quantified using the dichlorophenol-indophenol titration method. Statistical differences were evaluated with analysis of variance followed by Duncan’s Multiple Range Test at a significance threshold of p < 0.05.

Weight loss rose steadily in all groups as storage progressed, driven by transpiration, respiration, and dehydration, but the differences among treatments were not statistically significant. Maximum weight loss of 12.86 percent occurred in the Asuro extract treatment, possibly because compounds in the extract accelerate respiration, while the untreated control lost the least at 9.73 percent. Firmness told a different story: tomatoes treated with 100 percent Asuro extract retained the highest firmness, 5.71 Nmm⁻¹, on day 14, an effect the authors attribute to the antimicrobial activity of Justicia adhatoda. Firmness naturally declines as pectin breaks down into soluble forms and cell wall polysaccharides degrade, processes that moisture loss and enzymatic activity accelerate.

The chemical measurements revealed the clearest treatment effects. Total soluble solids climbed until day 10 as starch converted to sugars, then declined in nearly all treatments by days 12 and 14. The highest reading, 4.933 °Brix, appeared in the calcium chloride group, while the lowest, 3.466 °Brix, occurred at 200 ppm essential oil—a pattern consistent with delayed ripening, since slower carbohydrate conversion keeps soluble sugar accumulation in check. Titratable acidity fell continuously across the storage period as organic acids were consumed as respiratory substrates, dropping to a minimum of 0.21 percent at 200 ppm essential oil and holding highest at 0.36 percent in the Asuro treatment by day 14.

Vitamin C content increased through day 8 before declining, and the 200 ppm essential oil treatment preserved the highest level, 0.276 mgml⁻¹. The researchers suggest that higher concentrations of lemongrass oil limit oxygen exposure, inhibiting ascorbate activity and delaying oxidative degradation of the vitamin. The ratio of soluble solids to acidity, a key predictor of flavor palatability, differed significantly among treatments, peaking at 21.08 in the calcium chloride group and falling to 9.92 in the Asuro treatment at day 14, with the 200 ppm oil treatment close behind the leader at 17.12.

The study’s conclusion is that 200 ppm lemongrass essential oil delivered the best overall physicochemical performance, positioning essential oils as viable, non-hazardous alternatives to conventional chemical preservatives for tomato postharvest handling. The authors caution that the work was conducted on a single variety over a short period in a laboratory setting, and they recommend larger-scale trials across multiple varieties and concentrations before farmers adopt the practice. Cost is another hurdle: essential oils remain more expensive than synthetic chemicals, though the researchers suggest that blending them with organic acids could improve both efficacy and economics. For a country where most growers and traders have limited access to cold storage and proper postharvest facilities, a low-cost, plant-based vapor treatment could offer a practical way to cut losses in a crop that sits at the heart of both rural livelihoods and national diets.

Subject of Research: Postharvest preservation of tomatoes using lemongrass essential oil

Article Title: Effect of essential oil on shelf-life and quality attributes of tomato in Rupandehi, Nepal

Article References: Neupane, P., Poudel, B., Wosti, B., Pandey, S., Chaudhary, M., G. C., A., Khanal, R. P., & Chaurasia, J. (2025). Effect of essential oil on shelf-life and quality attributes of tomato in Rupandehi, Nepal. Innovations in Agriculture, 8, 1-10. https://doi.org/10.3897/ia.2025.142908

Image Credits: AI Generated

DOI: 10.3897/ia.2025.142908

Keywords: tomato, lemongrass essential oil, postharvest, shelf life, Nepal, Justicia adhatoda, vitamin C, titratable acidity, total soluble solids, food preservation, calcium chloride, agriculture

Water loss itself deserves closer attention because it drives several of the physical changes documented in the study. The pineapple crown, with its large surface area of leaves, is not merely an ornamental appendage; it can act as a substantial conduit for moisture, drawing water from the fruit or losing it directly to the surrounding air. Under the ambient conditions of the trial, held at 27 ± 2 °C and 85 ± 5 percent relative humidity, the vapor pressure deficit between the fruit surface and the atmosphere determines the rate of transpiration. Warm air holds more moisture, and when that air is not saturated, water migrates out of the fruit. The observed declines in fruit weight and dimensions after the early-storage peaks, particularly in the S3 treatment where weight and dimensions were greatest around Day 3 and then fell away, are consistent with this process. Weight loss not only reduces saleable mass, which matters economically when fruit is traded by the kilogram, but also causes visible wilting, shell shriveling, and a loss of the glossy appearance that consumers associate with freshness.

The °Brix measurement itself merits explanation for readers less familiar with postharvest physiology. A degree Brix corresponds roughly to one gram of sucrose per one hundred grams of solution, and although a refractometer reading actually reflects all dissolved solids, including organic acids and other compounds, sugars dominate the signal in pineapple juice. Because sweetness perception depends on the ratio of sugars to acids rather than on sugar content alone, °Brix on its own is an incomplete descriptor of eating quality. Two fruits with identical soluble-solids readings can taste very different if one carries substantially more titratable acidity. The authors of the study acknowledge this limitation directly, noting that titratable acidity, along with firmness, weight loss, microbial deterioration, and physiological disorders, should be incorporated into future work. The sugar-to-acid ratio, often called the maturity index in commercial practice, is the metric that most closely tracks consumer acceptability in pineapple, and its absence from the current dataset means the flavor implications of the observed °Brix trajectories remain provisional.

The finding that shelf life shortened as harvest maturity advanced follows a well-established pattern in tropical fruit handling, but the magnitude of the trade-off is what gives the result practical weight. Fruit harvested at S1, the 25 percent ripening stage, retained storability longer than any other treatment, giving handlers the widest window for transport, holding, and retail display. Fruit harvested at S4, fully ripe at harvest, offered the highest initial soluble-solids concentrations but the least flexibility, since any delay in marketing pushed the fruit past acceptable quality. This trade-off maps directly onto the structure of Fiji’s pineapple supply chain. Fruit destined for distant export markets or for processors who can hold product in cold storage can tolerate, and indeed may require, earlier harvest. Fruit sold into local municipal markets, roadside stalls, or the hospitality sector, where the interval between harvest and consumption is short, can be picked riper and still reach the consumer in good condition. The study’s central recommendation, that harvest maturity should be matched to the intended marketing channel, is essentially an instruction to treat ripening stage at harvest as a logistics decision rather than a purely agronomic one.

The context of Fiji’s postharvest losses sharpens the significance of these findings. The value-chain assessment cited in the article reported losses of 17.4 percent at the farm level and a further 8.2 percent at the market-vendor stage, for a combined 25.6 percent. In practical terms, roughly one quarter of the national pineapple crop never reaches a consumer in saleable condition. With national production recorded at 6,350 tonnes in 2021 and projected to approach 7,734 tonnes by 2024, even modest improvements in postharvest handling translate into meaningful absolute quantities of recovered fruit and income. Because the study was conducted entirely under ambient conditions rather than in refrigerated storage, its results describe the reality faced by most smallholder producers and informal market vendors in the country, for whom cold chain access is limited or absent. Ambient storage at tropical temperatures accelerates respiration, transpiration, and microbial growth simultaneously, compressing the window in which fruit remains marketable.

Temperature management deserves particular emphasis in this context because pineapple occupies an awkward middle ground among tropical fruits. It is chilling-sensitive, and exposure to temperatures below its tolerance range can trigger internal browning, water-soaked flesh, loss of shell gloss, and heightened susceptibility to decay. This rules out the aggressive low-temperature storage that works for temperate fruits, forcing handlers to operate within a narrower thermal band. The susceptibility to chilling injury also means that simply installing refrigeration is not a complete solution; storage protocols must respect the fruit’s physiological limits. Research into improved storage technologies, which the authors flag as a priority, would need to account for this constraint, exploring approaches such as controlled atmosphere storage, waxing, modified-atmosphere packaging, and careful humidity management that slow water loss without pushing temperatures into the injury zone.

The crown’s role in the water economy of the fruit is a detail with direct commercial implications. In many markets, pineapples are sold with crowns attached for aesthetic reasons and as a freshness indicator, yet the crown’s leaf surface area makes it an active site of transpiration. Removing or trimming the crown can reduce overall water loss and extend effective shelf life, a practice already common in some export supply chains. The study’s measurement of crown weight across ripening stages and storage days provides a foundation for quantifying this trade-off in the Fijian context, though the authors note that crown weight showed comparatively minor fluctuations in the fully ripe S4 treatment, suggesting that crown behavior may interact with fruit maturity in ways that warrant further investigation.

The repeated-measures design of the study, in which the same forty fruits were tracked from Day 0 through Day 14, offers both strengths and limitations worth appreciating. Following individual fruits over time captures the trajectory of change within each specimen and reduces confounding from between-fruit variation, which is substantial in pineapple given the fruit’s size and the variability of field conditions. However, ten fruits per ripening stage is a modest sample, and pineapple weight alone can vary by several hundred grams between individuals from the same field. The authors appropriately call for larger fruit populations evaluated across multiple seasons and locations before the findings are generalized. Seasonal effects on sugar accumulation, rainfall patterns during fruit development, and site-specific soil conditions can all shift the baseline °Brix and the rate of postharvest change, so single-season, single-location results should be treated as indicative rather than definitive.

The decision to continue observations past the estimated end of shelf life for some treatments, even though some shelf-life estimates concluded by Day 5, adds value by documenting how quality deteriorates rather than simply where it stops being acceptable. This kind of extended observation is useful for understanding failure modes. If weight loss accelerates in the later days of storage, or if °Brix plateaus once the concentration effect of water loss is exhausted, those patterns inform the design of storage interventions and the setting of realistic market deadlines. It also provides a caution against over-interpreting late-storage readings, since fruit that has passed its commercial window may still register respectable soluble-solids values while being unmarketable for reasons the current measurements do not capture, such as off-odors, fermentation, or visible decay.

Placing the findings in a broader agronomic frame, the ripening stages used in the study, expressed as percentages of full ripeness, correspond to observable shell color and flesh characteristics that growers can assess in the field. Harvest maturity indices for pineapple typically rely on shell color development, flesh firmness, and soluble solids, and the alignment between the S1 through S4 categories and these field-assessable traits determines how readily the study’s recommendations can be adopted by farmers without laboratory equipment. If S1 fruit can be reliably identified by shell appearance alone, the recommendation to harvest early for long-distance or delayed marketing becomes immediately actionable. If not, extension services would need to support growers with simple refractometers or standardized visual scales.

Finally, the economic logic of the trade-off deserves restatement in plain terms. Every additional day of ambient storability purchased by harvesting earlier comes at the cost of initial sweetness, since the non-climacteric fruit cannot make up the deficit after harvest. Every additional degree of sweetness secured by harvesting later comes at the cost of days lost from the marketing window. Neither choice is universally correct; the optimal point depends on the distance to market, the availability of cooling, the price premium for riper fruit, and the tolerance of the target consumer for slight under-ripeness. What the Fiji study contributes is a quantified starting point for that calculation under genuinely ambient tropical conditions, which is precisely the environment in which most of the country’s pineapple is actually handled and sold.

Subject of Research: Performance of smooth cayenne pineapple under tropical conditions: unravelling effects of postharvest duration and ripening stage

Article Title: Performance of smooth cayenne pineapple under tropical conditions: unravelling effects of postharvest duration and ripening stage

Article References: Colaitiniyara, K. K., Kumar, S. S., Wani, O. A., Cuquma, S., Jeelani, M. B., Alqahtani, N. A., & Al-mdallal, Q. (2026). Performance of smooth cayenne pineapple under tropical conditions: unravelling effects of postharvest duration and ripening stage. Frontiers in Horticulture, 5, Article 1941588. https://doi.org/10.3389/fhort.2026.1941588

Image Credits: AI Generated

DOI: 10.3389/fhort.2026.1941588

Keywords: pineapple, postharvest, Smooth Cayenne, shelf life, Brix, Fiji, ripening stage, tropical storage, Kaplan-Meier, food loss, Performance, smooth

The research team, working at Tarim University’s jujube nursery in Xinjiang, began by sorting a large collection of germplasm into three textural categories using texture profile analysis and professional sensory panels: soft-fleshed, crisp-fleshed, and hard-fleshed types. Nine representative varieties were selected, three from each category, and all trees were ten years old, identically managed, and sampled at five time points spanning 50 to 110 days after full bloom. At each harvest, seventy fruits were collected from all sides of the canopy, then divided into groups for mechanical texture testing, biochemical assays, and microscopy. This design deliberately preserved the natural diversity within each textural class, which matters for breeders and food processors who deal with real-world variation rather than laboratory clones.

The texture measurements told a story of divergence that begins surprisingly early. By 50 days after full bloom, hard-fleshed fruits already outperformed the other types in hardness, gumminess, and chewiness, and these initial differences were maintained or amplified as development proceeded. After 80 days, hard-fleshed fruit hardness climbed by 3.16 to 10.57 percent relative to the 80-day baseline, while soft and crisp varieties generally softened. Adhesiveness rose gradually in all fruits, cohesiveness declined, and by the final harvest the three groups were statistically distinct. The authors emphasize that mature texture is built upon, and magnified from, disparities established at the young-fruit stage, meaning the die is cast long before harvest.

Microscopy revealed the structural logic behind these numbers. Scanning electron microscopy showed that soft-fleshed jujubes possess loosely arranged, heterogeneous flesh cells riddled with large intercellular cavities, while crisp-fleshed fruits display cells that have expanded dramatically and undergone localized collapse, producing irregular tissue. Hard-fleshed fruits, by contrast, maintain turgid, uniformly small, tightly packed cells with virtually no cavities at all. Transmission electron microscopy added finer detail: soft-fleshed fruits have thin middle lamellae, the pectin-rich glue between cells, whereas hard-fleshed fruits show intact walls and compact lamellae. The quantitative differences were striking. By 110 days, crisp-fleshed cell areas were 77 to 198 percent larger than those of hard-fleshed fruits, and the cellular cavity area of soft-fleshed fruits reached 1.91 to 4.48 times that of crisp types and up to 12.90 times that of hard-fleshed fruits.

Beneath the visible architecture, the cell wall itself was being rebuilt. The team tracked three pectin fractions, water-soluble, ionic-soluble, and chelator-soluble pectins, along with hemicellulose and cellulose. All pectin fractions rose through development and peaked near maturity, but the accumulation was especially pronounced in hard-fleshed fruits from around 80 days onward. At the final two harvests, hard-fleshed fruits carried significantly more cellulose than the other types. This matters because ionic and chelator-soluble pectins form calcium-bridged networks that hold neighboring cells together, while cellulose microfibrils provide tensile strength. A fruit that keeps depositing these structural polysaccharides faster than enzymes can dismantle it effectively armors itself against softening.

The enzymes that remodel this wall behaved in ways that overturned simple expectations. Polygalacturonase, beta-galactosidase, pectinmethylesterase, and cellulase are conventionally cast as softening agents, yet their correlation with texture flipped depending on fruit type. In crisp-fleshed jujubes, polygalacturonase and beta-galactosidase activities correlated positively with hardness, springiness, gumminess, and chewiness. The authors propose a mechanism of controlled and limited degradation: in crisp fruits, these enzymes selectively trim weakly cross-linked pectin domains, relieving wall tension enough to permit controlled cell expansion without collapsing the overall network. In hard-fleshed fruits, the dense calcium-bridged pectin shield apparently limits enzyme access, so polygalacturonase activity instead reflects turnover of a minor, non-structural pectin pool and correlates negatively with hardness, while beta-galactosidase may aid wall remodeling that stiffens rather than softens.

Principal component analysis pulled the whole dataset into a coherent framework. Three components explained 85.10 percent of total variance, with the first, dominated by hardness, gumminess, and chewiness, accounting for 48.50 percent alone and functioning as a clean fruit texture factor. The second component loaded on the four cell wall enzymes, and the third on acidity and specific wall materials including ionic-soluble pectin, chelator-soluble pectin, and cellulose. Each textural type occupied its own region of this space: hard-fleshed fruits scored high on the texture factor, crisp fruits on the enzyme factor, and soft fruits on the acidity-wall factor. Notably, one crisp accession, C-2, separated cleanly from its peers, combining extremely high enzyme activity with high hardness and springiness and minimal cell collapse, a paradox the authors attribute tentatively to possible cellulose crystallinity, pectin esterification status, or spatial separation of enzymes from their substrates, all hypotheses requiring direct testing.

The practical implications reach from orchard to factory floor. The study pins 80 to 90 days after full bloom as the critical initiating window when cellular divergence begins, even though full biochemical separation of the types does not crystallize until 100 to 110 days. After roughly 90 days, hard-fleshed fruits enter what the authors call a processing-tolerant phase, able to withstand mechanical washing, pitting, long-distance transport, and drying without shriveling. Soft-fleshed fruits, with their porous, cavity-rich tissue, are ideally suited to sugar-curing and to products like jujube paste, jujube powder, and infant foods, where easy crushing and a smooth mouthfeel are assets. Crisp-fleshed fruits, whose cells show sensitivity to physical compression, demand gentler packaging and logistics for the fresh market. The mealy soft subtype S-3, which pairs large cavities with relatively higher structural polysaccharides within its group, challenges the assumption that cavities inevitably mean collapse.

Perhaps the most forward-looking contribution is the suggestion that polygalacturonase and beta-galactosidase activity patterns could serve as type-specific biomarkers for breeding programs, accelerating marker-assisted selection of varieties tailored to drying, fresh consumption, or processing endpoints. The authors also point toward integrating these biochemical markers with non-destructive sorting technologies such as near-infrared spectroscopy or hyperspectral imaging, which could classify fruit texture in real time on packing lines and route each batch to its most profitable use. The researchers are careful to flag the limits of their work: the proposed causal chain from structural change to wall remodeling to final texture rests on correlative evidence, hormone signals such as ethylene and abscisic acid were not directly measured, and the fine chemistry of pectin esterification and calcium binding remains to be worked out. Even so, the study delivers something rare in fruit biology, a unified account of how one enzyme can soften one fruit and stiffen another, depending entirely on the cellular and biochemical context in which it acts.

Subject of Research: Cell wall metabolism and cellular structure regulating texture development in jujube fruit

Article Title: Cell wall metabolism and cellular structure synergistically regulate texture in jujube fruit: implications for quality classification and processing adaptability

Article References: Yan, M., Zhang, X., Lin, M., Shi, Q., Hao, Q., Li, X., Zhou, X., & Wu, C. (2026). Cell wall metabolism and cellular structure synergistically regulate texture in jujube fruit: implications for quality classification and processing adaptability. Food Chemistry: X, 39, Article 104536. https://doi.org/10.1016/j.fochx.2026.104536

Image Credits: AI Generated

DOI: 10.1016/j.fochx.2026.104536

Keywords: jujube, fruit texture, cell wall, pectin, cellulose, polygalacturonase, beta-galactosidase, food processing, postharvest, plant microscopy, principal component analysis, breeding

A research team led by Eliwanzita Sospeter, working with Phebe Ding and Teh Huey Fang, harvested thirty fully ripe Musang King durians from commercial orchards in Raub, Pahang, during the November 2022 season. The fruits, each weighing around 1.4 kilograms and free of defects, were rushed to a processing facility in nearby Bentong for cryogenic freezing. Researchers verified that the thermal centre of each fruit reached roughly minus 19.5 degrees Celsius, a threshold that satisfies international quick-frozen food standards, before the fruits were sealed in polystyrene boxes and placed in frozen storage. Six fruits were pulled from the freezer at each of five time points: zero, three, six, nine and twelve months. After a standardized two-hour thaw at 25 degrees, matching common Malaysian commercial practice, the pulp from each fruit was analyzed for texture, acidity, sugars, volatile aroma compounds, polar metabolites and fatty acids.

The physicochemical results were a study in contrasts. Pulp firmness and soluble solids content, the two attributes most directly tied to the eating experience, barely budged across the entire year, a testament to how effectively cryogenic freezing limits ice-crystal damage to cellular structures. Yet the subtler chemistry told a different story. Titratable acidity fell by nearly 26 percent over twelve months, reducing sugars rose by 20 percent, and the ratio of soluble solids to acidity climbed by more than 39 percent. Because the balance between sweetness and acidity is central to how consumers perceive fruit flavor, these shifts matter even if a refractometer reading looks unchanged. The researchers attribute the declining acidity to gradual changes in the organic acid pool, potentially amplified during thawing, while the rising reducing sugars likely reflect the conversion of non-reducing sugars into their reducing forms.

To peer deeper into the fruit’s biochemistry, the team turned to gas chromatography coupled with high-resolution Orbitrap mass spectrometry, an analytical setup capable of resolving dozens of compounds in a single run. From the polar metabolite fraction, they putatively identified 41 compounds spanning amino acids, sugars, organic acids and sugar alcohols. Principal component analysis showed that samples separated cleanly by storage duration, with the first two components alone capturing nearly 55 percent of the variation. Freshly frozen fruit and three-month samples clustered together, indicating that the early months of storage are chemically quiet, but by six months the metabolite landscape had shifted decisively, and nine- and twelve-month samples carried their own distinct signatures.

A supervised modeling approach called partial least squares-discriminant analysis then pinpointed the compounds most responsible for those differences. Nineteen polar metabolites emerged as discriminant markers, including eight sugars, four organic acids, three amino acids and derivatives, two sugar alcohols, a nucleoside and an amine. Notably, the amino acids L-aspartic acid, glutamic acid and 3-hydroxyproline all increased significantly as storage lengthened. Since glutamate and aspartate are key contributors to umami and sour taste notes in fruit, their accumulation has direct flavor implications. The authors are careful about interpretation, however: at minus 20 degrees, active stress metabolism is implausible. They suggest instead that ice-induced disruption of vacuolar and cellular membranes exposes proteins to peptidases, allowing slow proteolytic degradation during storage and accelerated breakdown during thawing to release free amino acids.

The sugar profile evolved in equally intriguing ways. Levels of D-mannose, sucrose, D-xylose, palatinose and several other carbohydrates rose significantly, while mannose-6-phosphate declined. The sucrose increase is compatible with a cryoprotective role, since sugars are known to stabilize membranes and maintain osmotic balance during freezing stress in many plant tissues. But the researchers also raise a more prosaic possibility: ice crystals that form and recrystallize over months of storage progressively rupture cellular compartments, and when the fruit is later thawed and extracted, those damaged tissues simply release more of their soluble contents. In other words, some of the measured chemical change may reflect increased extractability rather than genuine biochemical transformation, a caveat the team acknowledges throughout the study.

Pathway enrichment analysis mapped the discriminant metabolites onto known biochemical networks and highlighted three significantly enriched routes: alanine, aspartate and glutamate metabolism; galactose metabolism; and glyoxylate and dicarboxylate metabolism. Citric acid, a central intermediate of the tricarboxylic acid cycle, declined steadily and mirrored the drop in titratable acidity, while succinic, gluconic and glyceric acids all rose. The enrichment analysis identifies biochemical associations rather than proving mechanisms, but it provides a coherent framework linking the observed shifts in amino acids, sugars and organic acids to the fruit’s core metabolic architecture.

The volatile compounds that give durian its infamous aroma showed their own time-dependent evolution. The headspace of Musang King is dominated by esters and sulfur compounds, and the profiling captured 53 volatile substances overall. The story here was one of loss and replacement: fruity, sweet-smelling esters such as ethyl butanoate, methyl butanoate and ethyl propanoate, which are hallmark contributors to durian’s appealing notes, declined steadily and in some cases vanished entirely by twelve months. Meanwhile, sulfur-heavy compounds including trithiolanes and thiazoles, along with several alcohols, increased in the three-, six- and twelve-month samples. Curiously, methyl octanoate and methyl hexanoate, absent at the start, appeared only after six months of storage, suggesting that cumulative structural damage from ice recrystallization may progressively liberate compounds that were previously locked away. Thirteen volatile markers were flagged as discriminant compounds, and together with the metabolite markers they paint a picture of an aroma profile that drifts measurably away from the fresh fruit over the course of a year.

One dataset offered reassuring stability: the relative proportions of the nine fatty acids identified in the pulp showed no significant change across the full storage period, echoing earlier findings in sweet corn and olives stored at sub-zero temperatures. Because the analysis measured relative composition rather than absolute concentrations, the authors caution that absolute amounts could still have shifted. The final integration step, a multiple factor analysis combining all four data blocks, accounted for 75 percent of total variance in its first two dimensions and revealed a non-monotonic trajectory: minimal change from zero to three months, a pronounced shift by six months, and then a partial reversal in direction at nine and twelve months. The volatile and metabolite datasets drove the primary dimension of variation, while physicochemical attributes and fatty acids contributed along a separate axis.

The study comes with honest limitations. All samples were thawed before analysis, so storage effects and thawing effects cannot be fully disentangled, and the discriminant markers were identified at putative level without confirmation against authentic reference standards. No sensory panel was involved, so the link between these chemical shifts and what a durian lover actually tastes remains to be established. Even so, the work delivers something the Malaysian durian industry has lacked: a molecular timeline of its flagship export’s journey through the frozen supply chain. With thirteen flavor-linked markers now identified, the groundwork is laid for validated quality tests that could tell exporters, regulators and consumers exactly how much chemical drift a given frozen Musang King has experienced, and ultimately help define how long the king of fruits can reign from the freezer without losing its crown.

Subject of Research: Chemical quality changes in Musang King durian during 12 months of frozen storage

Article Title: Integrated metabolomic and chemometric profiling reveals quality-related chemical changes in Musang King durian during long-term frozen storage

Article References: Sospeter, E., Ding, P., & Fang, T. H. (2026). Integrated metabolomic and chemometric profiling reveals quality-related chemical changes in Musang King durian during long-term frozen storage. Journal of Agriculture and Food Research, 31, Article 103314. https://doi.org/10.1016/j.jafr.2026.103314

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103314

Keywords: durian, Musang King, frozen storage, metabolomics, volatile organic compounds, fatty acids, cryogenic freezing, food quality, flavor chemistry, GC-MS, postharvest, Malaysia

The story of dopamine in plants is older than many researchers realise. The molecule was first detected in plant tissue in the saguaro cactus, where scientists observed a spike in endogenous dopamine within five minutes of tissue wounding, hinting at a protective role. Earlier work in 1958 had already identified catecholamines and serotonin in bananas, and dopamine was subsequently confirmed in banana peel and pulp, plantains and avocados. Bananas remain one of the richest known plant sources of the compound, and its antioxidant power there is striking: dopamine outperforms glutathione, ascorbic acid, catechin gallate and common synthetic antioxidants in free-radical scavenging assays. What has changed in recent years is the depth of mechanistic understanding, with studies now tracing dopamine’s effects from gene expression to whole-plant physiology.

Chemically, dopamine is identical across kingdoms. It is a benzene ring bearing two adjacent hydroxyl groups, the catechol moiety characteristic of catecholamines, attached to an ethylamine side chain. That catechol group is the secret of its antioxidant behaviour, donating electrons and hydrogen atoms to neutralise reactive oxygen species and, in some cases, chelating metals to disarm free radicals. The primary amine makes dopamine an organic base capable of forming salts in acidic conditions, while both functional groups hydrogen-bond readily with water, making the molecule highly polar. In animals, dopamine is synthesised from the amino acid tyrosine through a single route in which tyrosine hydroxylase acts as the rate-limiting enzyme. Plants, remarkably, run two alternative pathways: one decarboxylates tyrosine to tyramine via tyrosine decarboxylase before hydroxylation by monophenol hydroxylase, while the other hydroxylates tyrosine to L-DOPA first and then decarboxylates it with DOPA decarboxylase. Which route dominates depends on enzyme availability and plant species.

Inside the plant cell, dopamine appears to accumulate mainly in the vacuole, which serves as a storage compartment, with smaller quantities detected in the cytoplasm. Its production sites shift with need, from roots to leaves, and its concentration ranges from nanograms to micrograms depending on species and developmental stage. In opium poppy, dopamine is synthesised in young rosette leaves and declines as flowering begins. This spatial and temporal flexibility underscores a key theme of the review: dopamine is not a static metabolite but a dynamic, stress-responsive signal whose behaviour is tailored to the tissue, the species and the threat at hand.

The physiological reach of dopamine in plants is broad. Under stress, photosynthesis typically collapses as reactive oxygen species oxidise the pigments that capture light, forcing plants to close their stomata and conserve energy at the cost of growth. Dopamine intervenes at multiple points in this cascade. It stabilises the light-dependent reactions of photosynthesis, maintains stomatal conductance, preserves chlorophyll and supports optimal transpiration and carbon assimilation. In apple seedlings exposed to drought, a treatment of 100 micromolar dopamine enhanced net photosynthetic rate, relative water content, stomatal conductance and the content of chlorophyll a and b. Dopamine also reshapes root architecture, stimulating root vigour and elongation so that plants can explore soil for water and nutrients more effectively. Intriguingly, roots themselves secrete dopamine as a major exo-metabolite, suggesting it plays an active role at the root-soil-microbe interface.

At the molecular level, dopamine’s influence extends deep into gene regulation. Transcriptomic analysis of drought-stressed apple plants treated with dopamine revealed upregulation of calmodulin and calmodulin-like genes and cyclic nucleotide-gated channels involved in calcium signalling. The transient elevation of cytosolic calcium during stress initiates a cascade of adaptive cellular responses that activate downstream transcription factors, including MYBs and WRKYs. Because superoxide dismutase is a calmodulin-dependent enzyme, and glutathione peroxidase activation is also linked to calmodulin, dopamine’s calcium signalling effectively amplifies the plant’s antioxidant arsenal. The review also documents dopamine’s extensive crosstalk with phytohormones, including auxin, gibberellic acid, melatonin, abscisic acid, jasmonic acid and ethylene, fine-tuning the growth-defence trade-offs that determine how a plant allocates its limited resources under threat.

Each stress type reveals a different facet of dopamine’s versatility. Under salinity, exogenous dopamine in Malus hupehensis inhibited excess sodium and chloride uptake while enhancing the acquisition of potassium, nitrogen, phosphorus, sulphur, copper and manganese. Upregulation of genes such as MdHKT1, MdNHX1 and MdSOS1 shows dopamine engaging the salt overly sensitive pathway, the core salt-defence system in plants, pumping sodium into vacuoles and expelling it from root cells. In tomato seedlings, 100 micromolar dopamine maintained calcium-to-sodium and potassium-to-sodium ratios and produced striking gains: root dry weight increased by 286.84 percent, plant height by 108.37 percent and leaf area by 158.28 percent compared with untreated controls. Under cadmium stress in apple, dopamine reshaped the rhizosphere microbial community, enriching beneficial bacteria such as Frankia, Bradyrhizobium and Streptomyces and shifting keystone species in ways that helped the plant resist the metal.

Nitrogen stress and temperature extremes add further chapters. In cucumber grown under excess nitrate, 150 micromolar dopamine improved root growth, photosynthesis and antioxidant activity while upregulating genes for sucrose phosphate synthase, nitrate reductase and other enzymes that coordinate carbon and nitrogen metabolism. In apple, dopamine under low-nitrogen conditions increased expression of nitrate transporter genes and activated MdORG2, a transcription factor that boosts the plant’s own dopamine-synthesising machinery. Against cold, dopamine protected watermelon and grape seedlings by accumulating polyamines and osmolytes and bolstering antioxidant systems. Perhaps most commercially intriguing are the postharvest results: dopamine treatment significantly mitigated chilling injury in bananas stored at 7 degrees Celsius for 21 days and kiwifruits stored at 1 degree Celsius for 120 days, by activating the phenylpropanoid pathway, raising endogenous proline, GABA and glycine betaine, and preserving membrane integrity.

Dopamine also strengthens plant immunity against pathogens. In apple replant disease caused by Fusarium solani, 150 micromolar dopamine enhanced endogenous dopamine biosynthesis, reduced root damage and upregulated defence genes encoding chitinase and beta-1,3-glucanase, while increasing tyramine content and cell wall-bound amine deposition. Against Valsa mali infection in apple, resistance came through elevated phenolic content and salicylic acid. In pear, a foliar spray of 100 micromolar dopamine imparted resistance to Botryosphaeria dothidea by enhancing autophagy activity in host cells. Even allelopathic threats fall within its scope: dopamine counteracted phloridzin, a growth-inhibiting compound that disrupts apple rhizosphere communities, by lowering reactive oxygen species and enriching beneficial nitrogen-cycling microbes.

Significant gaps remain before dopamine can be deployed at scale. Research has concentrated on a narrow set of crops, chiefly apple rootstocks, tomato, cucumber and duckweed, while cereals, legumes and tropical fruits remain largely unexplored. Unlike in animals, no dopamine receptors have been identified or characterised in plants, leaving open the fundamental question of how the molecule is perceived. The threshold between beneficial and phytotoxic doses is poorly defined, and there is no regulatory framework governing exogenous dopamine use in agriculture. The review’s authors point to biotechnology as one promising route: overexpressing the tyrosine decarboxylase gene could raise endogenous dopamine levels and confer climate resilience without repeated spraying. Combined applications with melatonin, brassinosteroids and beneficial microbes offer further synergistic potential. If those mechanistic and safety questions can be answered, dopamine may graduate from laboratory curiosity to a next-generation regulator of crop resilience, extending its celebrated career from the animal brain to the world’s fields and orchards.

Subject of Research: The role of dopamine as a stress-regulating signalling molecule in plants

Article Title: Beyond neurotransmission: dopamine as an emerging biotic and abiotic stress regulator in plants

Article References: Shinde, D., & Pareek, S. (2026). Beyond neurotransmission: dopamine as an emerging biotic and abiotic stress regulator in plants. Stress Biology, 6(1), Article 24. https://doi.org/10.1007/s44154-026-00291-8

Image Credits: AI Generated

DOI: 10.1007/s44154-026-00291-8

Keywords: dopamine, plant stress, abiotic stress, biotic stress, antioxidant, reactive oxygen species, calcium signalling, phytohormones, salinity tolerance, drought tolerance, postharvest, plant signalling

The research, conducted with the southern highbush cultivar ‘Biloxi’, focused on calcium, a mineral with a dual personality in plant biology. Structurally, calcium ions cross-link pectin molecules in the middle lamella of cell walls, forming calcium pectate bridges that give tissues their rigidity and contribute directly to fruit firmness. Signaling-wise, calcium acts as a ubiquitous secondary messenger in responses to growth cues and abiotic stress. But calcium has an awkward logistical constraint: it moves almost exclusively through the xylem’s transpiration stream and has very limited mobility in the phloem, the plant’s sugar-transport highway. Because blueberry fruits transpire relatively little, delivering adequate calcium to developing berries is a persistent physiological challenge.

To probe this challenge, the researchers grew twelve-month-old ‘Biloxi’ plants in 25-liter containers filled with red tezontle, a porous volcanic substrate, under a precision fertigation system in northern Sinaloa. They arranged a 3 × 3 factorial experiment combining three relative calcium proportions (30, 45 and 60 percent of the total cationic pool) with three nutrient-solution osmotic potentials (−0.032, −0.052 and −0.072 megapascals). Crucially, raising the calcium share required reciprocal reductions in potassium and magnesium, so the treatments represent different cationic balances rather than isolated calcium doses. Osmotic potential was set by proportionally scaling all ionic concentrations, calculated from the total millimolar content of the solution, and pH was held tightly between 5.0 and 5.5, the range favored for blueberry nutrient uptake.

The results on vegetative growth were strikingly nonlinear. Shoot length and shoot number responded to a significant interaction between calcium proportion and osmotic potential, peaking not at the mildest solution but at the intermediate one: plants grown at −0.052 megapascals with 60 percent relative calcium produced the longest shoots, 26.58 centimeters, and the most shoots per plant, 24.58. At the most restrictive potential of −0.072 megapascals, growth fell sharply, with the 30 percent calcium combination yielding just 16.08 centimeters and 13.17 shoots. The authors suggest the intermediate treatment may have acted as a mild, beneficial stress, a hormesis-like stimulus, though they caution that the physiological markers needed to prove such a mechanism were not measured.

Calcium’s journey through the plant left a vivid fingerprint in the canopy. Using a portable ion-selective electrode on fresh leaf extracts, the team tracked soluble calcium across three strata and three phenological stages. Old leaves at the base accumulated dramatically more calcium than young leaves at the top, with basal concentrations reaching 7802.50 parts per million during fruiting, roughly 4.3 times the maximum recorded in apical leaves. Young leaves showed their highest calcium early in the cycle and declined toward fruiting, while basal leaves climbed steadily, a pattern consistent with calcium’s inability to be remobilized through the phloem once deposited. Under the most negative osmotic potential, calcium in young leaves dropped to as little as 751.25 parts per million, and even at the highest calcium proportion the apical concentration fell by 38 percent compared with the mildest solution.

Dry matter accumulation told a complementary story. Total biomass responded to the main effects of both factors, reaching a maximum of 364.55 grams per plant at −0.032 megapascals with 60 percent calcium and a minimum of 217.83 grams under the most restrictive combination, a 40.2 percent gap. The calcium-by-osmotic interaction was significant only for the root-to-shoot ratio, which rose from around 0.19 under mild conditions to 0.242 at −0.072 megapascals with 30 percent calcium, hinting that plants under osmotic restriction shifted investment toward roots, with the degree of that shift depending on the cationic balance.

The fruit itself revealed perhaps the most commercially consequential findings. Fruit calcium concentration, measured by atomic absorption spectrophotometry, responded independently to both factors: at 30 percent relative calcium, tightening the solution from −0.032 to −0.072 megapascals cut fruit calcium by 42.7 percent, from 1718.70 to 983.70 milligrams per kilogram of dry matter. Raising the calcium proportion from 30 to 60 percent boosted fruit calcium by 48.8 percent under mild conditions and by 72.4 percent under the most restrictive ones. Notably, the combination of −0.072 megapascals with 60 percent calcium achieved 1695.99 milligrams per kilogram, statistically comparable to the mild solution at 30 percent calcium, showing that a richer cationic calcium share can offset, at least in outcome, a tougher osmotic environment.

Physicochemical quality shifted in a different direction. More negative osmotic potential drove soluble solids upward, with ‘Brix reaching 16.90 at the 30 percent calcium combination, a 42.8 percent increase over the mild solution, while titratable acidity fell to its lowest value of 0.57 percent under the same conditions, pushing the maturity index to 30.05. Higher calcium proportions moderated these swings, keeping acidity at 0.87 percent and the maturity index at 17.21 under the most restrictive potential. The sweetest, most mature fruit therefore emerged from the harshest osmotic treatment with the least calcium, a combination that proved disastrous for texture.

Firmness and surface wax load, the two structural attributes most relevant to shelf life, followed a clear pattern: both peaked under the mildest osmotic potential and the highest calcium proportion. Maximum firmness reached 84.25 on the Shore scale and maximum wax load 0.53 milligrams per square centimeter at −0.032 megapascals with 60 percent calcium, while the harshest combination with 30 percent calcium produced the lowest values, 50.88 and 0.19 respectively, a 39.6 percent firmness deficit and a 64.1 percent wax deficit. Strikingly, at −0.072 megapascals, raising the calcium proportion from 30 to 60 percent increased wax load by 147 percent and firmness from 50.88 to 77.18, suggesting the epicuticular bloom that gives blueberries their characteristic powder-blue sheen is highly sensitive to the root-zone ionic environment. The authors note the chloroform extraction captures a broad surface lipid fraction, so they conservatively report it as surface wax load rather than epicuticular wax alone.

Perhaps the most practical takeaway is that there is no single optimal recipe. The treatment that maximized vegetative growth, −0.052 megapascals with 60 percent calcium, was not the one that maximized firmness and wax, which required −0.032 megapascals at the same calcium share. For growers, this means nutrient-solution management should be tuned to the production goal, whether canopy building or fruit durability. The findings arrive at a pertinent moment: Mexico ranks among the world’s leading blueberry exporters, and postharvest performance is a decisive competitive edge. Because the calcium treatments inherently altered potassium and magnesium as well, and because transpiration, xylem flow and calcium flux were not directly measured, the authors frame their mechanistic explanations as plausible rather than proven. Still, the study demonstrates that the invisible chemistry of the root zone, the osmotic pull of the solution and the relative standing of calcium among its fellow cations, ripples all the way to the bite of a berry, opening a path toward fruit engineered for toughness before it ever leaves the vine.

Subject of Research: Effects of nutrient-solution osmotic potential and relative calcium proportion on calcium distribution and fruit structural quality in hydroponic blueberry

Article Title: Osmotic potential and relative calcium proportion interact to determine fruit structural integrity in blueberry (Vaccinium corymbosum L.)

Article References: Montoya, F. P., Martínez, F. R., Bautista, E. L., Verduzco, C. F., Peralta, R. M., & Valdez, J. A. M. (2026). Osmotic potential and relative calcium proportion interact to determine fruit structural integrity in blueberry (Vaccinium corymbosum L.). Discover Agriculture, 4(1), Article 309. https://doi.org/10.1007/s44279-026-00784-0

Image Credits: AI Generated

DOI: 10.1007/s44279-026-00784-0

Keywords: blueberry, calcium, osmotic potential, hydroponics, fruit firmness, surface wax, cationic balance, Vaccinium corymbosum, plant nutrition, fruit quality, nutrient solution, postharvest

The review, led by Jingsong Guo and colleagues at institutions including Guangdong Ocean University, takes an unusual approach for a fruit crop. Rather than cataloguing jackfruit’s nutritional composition or processing technologies, as previous reviews have done, it asks a deceptively simple question: when does genetic variation actually become a measurable fruit trait, and when has that trait been proven to matter in a finished product? To answer it, the team searched the Web of Science Core Collection in August 2026 using four complementary modules covering genetic diversity, genotype-associated quality variation, molecular mechanisms, and postharvest behaviour. The searches returned 347 raw hits, which collapsed to 292 unique records; a retrospective audit classified 185 as broadly relevant, and 47 of those underwent detailed extraction, ultimately yielding a cited evidence base of 48 sources.

What that evidence base reveals is a field with abundant raw material but weak connective tissue. Jackfruit germplasm studies report enormous variation in fruit mass, edible recovery, soluble solids, acidity, firmness, pulp colour, aroma and bioactive compounds. Molecular surveys using AFLP and SSR markers, and more recently chromosome-scale genome assemblies and dense SNP datasets, confirm substantial genetic differentiation. A landmark study combined a reference genome with resequencing of 295 Chinese landraces and identified candidate genomic regions associated with domestication and fruit traits, including flesh texture. Genotyping-by-sequencing of Bangladeshi accessions has produced tens of thousands of filtered SNPs. Marker availability, the review concludes, is no longer the bottleneck.

The bottleneck is validation. The authors developed a four-level evidence hierarchy to classify how close each processing study comes to a genotype-specific product claim. Level I covers trait-based inference, where raw-fruit characteristics are used to propose an end use without any product testing. Level II requires direct measurement of process-relevant raw-material properties, such as how tender jackfruit’s mechanical properties change across maturity stages. Level III demands that a defined material enter an actual processing or postharvest system with at least one product or storage endpoint measured. Level IV — the gold standard — requires multiple genetically characterized genotypes, matched or explicitly standardized physiological states, identical processing conditions and direct comparison of final-product performance. Among the 21 primary studies that directly informed processing-suitability evidence, the tally was four at Level I, four at Level II, 13 at Level III and zero at Level IV.

That zero matters because genotype does not arrive at a processor as a fixed phenotype. Jackfruit is consumed at radically different physiological stages: immature fruit serves as a vegetable or fibrous ingredient, ripe bulbs are eaten fresh, and harvested fruit enters fresh-cut, dried, preserved and fermented products. Each use favours a different raw material, and each is judged by different criteria. A dessert fruit lives or dies on sweetness and aroma; fresh-cut material must hold its structure through handling and cold storage; immature-food applications can actually benefit from fibrous texture before sugars accumulate. Maturity, ripening and postharvest history all alter sugars, firmness, colour, aroma, respiration and metabolite profiles, which means two genotypes harvested on the same day and stored for the same number of days may be in entirely different biological states.

The review argues that four descriptors must be kept strictly separate: harvest maturity, physiological ripeness, chronological storage duration and processing readiness. Static measurements can hide crucial differences — two varieties may reach the same total soluble solids at different times, or one may retain firmness far longer while developing a similar flavour profile. Trajectory measurements such as softening rate, time to a target sugar-acid balance and duration of acceptable post-cut quality would be far more predictive of commercial value than single-point snapshots, yet they remain rare in the literature. Fresh-cut research illustrates the stakes: cutting accelerates water loss, browning, respiration and microbial deterioration, so bulbs that look identical at the start can diverge sharply after processing. Modified-atmosphere packaging, ethanol vapour treatment, methyl jasmonate application and calcium chloride plus heat treatment have all been shown to reshape quality trajectories, but almost always in a single cultivar.

Texture currently offers the strongest mechanistic bridge between jackfruit genomics and a commercial trait. The genome study identified a candidate region associated with flesh texture with expression evidence pointing to a polygalacturonase-related mechanism, while independent work tracked firmness, cell-wall polysaccharides and softening enzymes through maturation and ripening. Both converge on pectin disassembly as a driver of softening. But the review is careful to note that this does not establish a causal allele usable predictively across germplasm — that would require independent populations, allele-specific functional tests and standardized texture phenotyping. Similar caution applies to colour and aroma: integrated transcriptomic-metabolomic work links pulp colour differences to coordinated carotenoid and flavonoid metabolism, and multi-omics comparisons tie cultivar aroma differences to several metabolic pathways rather than one diagnostic compound, but none of these associations has been causally validated.

The review also dismantles some common shortcuts. Total soluble solids, the workhorse measurement of fruit sweetness, is not equivalent to perceived sweetness, which also reflects acidity, individual sugars, aroma and texture. Instrumental colour is not a proxy for carotenoid concentration unless pigment chemistry is measured directly. Antioxidant assays are not evidence of health benefit. Fruit mass is not marketable yield, since rind, core, seeds and edible bulbs account for wildly different fractions across accessions. And a meat-like fibrous structure in immature jackfruit is a technological property, not nutritional equivalence to animal protein — the relatively low protein content of immature fruit means plant-based products may require complementary protein sources and direct nutritional evaluation.

To move the field forward, the authors lay out a research pipeline that begins not with more diversity surveys but with a well-designed, well-characterized germplasm panel with sufficient genetic and geographic breadth and clonal replication. Candidate genotypes should be evaluated in common-garden and multi-location, multi-season trials, with mixed models partitioning genotype, environment and genotype-by-environment effects; rootstock, nutrition, season and management should be recorded as explanatory factors rather than absorbed into the genotype label. Physiological state should be standardized explicitly using measurable variables such as firmness, sugar-acid balance or colour, not assumed from harvest dates. Then comes the missing experiment: several genetically characterized genotypes at objectively matched physiological states, processed under one protocol, with process yield, texture, colour, flavour, nutrient retention, storage stability and microbial safety measured directly. Repeating the comparison across seasons would reveal whether genotype rankings are stable or shift with production context.

The authors are equally clear that laboratory success is not the finish line. Sensory and economic evidence is far thinner than compositional or postharvest evidence, and a technically successful product may remain commercially unattractive once usable yield, energy, packaging, waste and market response are counted. Consumer preference and willingness-to-pay studies, such as recent work on red-fleshed jackfruit in southern India, point toward the kind of validation deployment requires. Notably, the review concludes that near-term progress does not depend on genomic prediction at all: existing diversity can already support clonal selection, better parent choice, tighter maturity control and direct product tests of elite material. Marker-assisted selection becomes worthwhile only after large-effect loci are independently validated, and genomic prediction will need substantially larger and more reproducible training datasets than currently exist. The practical priority, the authors argue, is not to find a universally superior jackfruit, but to determine which genotype, expressed under which physiological state and production context, performs reproducibly in a defined end use — a shift that would finally connect germplasm improvement with food-product development while keeping technological, nutritional, consumer and economic claims anchored to the evidence that actually measures them.

Subject of Research: Evidence gaps in linking jackfruit genotype, fruit quality physiology and end-use product performance

Article Title: Bridging genotype, dynamic fruit quality and end-use performance in jackfruit: evidence gaps and validation priorities

Article References: Guo, J., Chen, C., Peng, S., Zhang, H., Huang, M., Zhou, X., & Feng, F. (2026). Bridging genotype, dynamic fruit quality and end-use performance in jackfruit: evidence gaps and validation priorities. Journal of Agriculture and Food Research, 31, Article 103323. https://doi.org/10.1016/j.jafr.2026.103323

Image Credits: AI Generated

DOI: 10.1016/j.jafr.2026.103323

Keywords: jackfruit, Artocarpus heterophyllus, genotype, fruit quality, postharvest, fresh-cut, food processing, genomic prediction, phenotyping, plant breeding, evidence validation, value-added products

The fruit in question, ‘Nam Dok Mai Si Thong’, is a flagship Thai mango cultivar that generated an export value of 95 million US dollars in 2021. Like all mangoes, it is a climacteric fruit, meaning it continues to ripen after harvest, driven by the plant hormone ethylene. Under ambient conditions of roughly 27 to 30 degrees Celsius, freshly harvested mangoes last only four to eight days before softening, yellowing, and succumbing to microbial infection. The most serious threat is anthracnose, caused by fungi of the genus Colletotrichum, which can destroy up to 45 percent of the harvest. Conventional control relies on synthetic fungicides, but consumer demand for residue-free produce and tightening regulations have pushed scientists to seek natural alternatives.

Essential oils from aromatic plants have attracted considerable attention for exactly this purpose. Thai basil, Ocimum basilicum var. thyrsiflora, produces an oil rich in bioactive compounds, and the team led by Tibet Tangpao and Piyachat Sunanta of Chiang Mai University set out to test it under realistic postharvest conditions. Gas chromatography-mass spectrometry revealed that the oil was dominated by estragole, a phenylpropanoid accounting for roughly 90 percent of the total volatile content, alongside smaller amounts of fenchyl alcohol, eucalyptol, and T-cadinol. Crucially, the researchers also ran a headspace-trap analysis at 40 degrees Celsius to see which compounds actually escape into the air. Here the picture shifted: estragole showed the highest relative release at 37 percent, followed by beta-cis-ocimene at just over 10 percent, with trans-alpha-bergamotene, linalool, and eucalyptol trailing behind. This distinction matters because in a vapour-phase, non-contact treatment, the composition of the air surrounding the fruit, not the bulk composition of the oil, determines what the fruit actually experiences.

The experiment itself was meticulous. The team purchased 135 uniform, undamaged mangoes, each weighing approximately 420 grams, from an orchard in Mae Taeng District, Chiang Mai, during the commercial harvest. Each fruit was placed in its own one-litre perforated polypropylene container, and the oil was pipetted onto cotton wool inside at concentrations ranging from 13 to 500 microlitres per container. The containers were sealed and stored at 17 to 19 degrees Celsius with 75 to 85 percent relative humidity for 16 days, with destructive sampling at days 5, 8, 12, and 16. A separate antifungal assay used mangoes artificially wounded and inoculated with a confirmed Colletotrichum isolate, originally recovered from diseased ‘Nam Dok Mai Si Thong’ fruit and verified by RNA sequencing.

Over the 16 days, storage time emerged as the overwhelming driver of change. Peel colour shifted as chlorophyll degraded and yellow carotenoid pigments accumulated, firmness collapsed by up to 99 percent as cell wall-degrading enzymes such as polygalacturonase and pectin methylesterase dismantled pectin and hemicellulose networks, and weight loss climbed steadily through transpiration and respiration. Pulp pH rose from 3.22 to about 5.44 while titratable acidity plummeted from 1.19 percent to a mere 0.06 percent, reflecting the consumption of organic acids in the tricarboxylic acid cycle. Total sugars rose from 0.15 grams per gram to a peak of 0.39 grams per gram at day 12 before crashing to 0.05 grams per gram as senescence set in, and electrolyte leakage, a marker of membrane breakdown, reached 58.45 percent by the end of storage.

Against this backdrop, the basil oil vapour exerted a secondary, modulatory influence concentrated on the fruit’s exterior. BEO concentration significantly affected the yellowness parameter and overall colour difference, and at 500 microlitres per litre it reduced peel redness by 13.99 percent relative to untreated controls, indicating a delay in colour development. Lower concentrations were associated with better firmness retention, while the highest concentration failed to protect against softening and even pushed weight loss to 7 to 8 percent, comparable to the control. The researchers interpret this as a concentration-dependent trade-off: mild vapour exposure may slow transpiration and preserve cuticular integrity, whereas heavier doses may trigger stress or phytotoxic responses that disrupt membranes and accelerate water loss. Notably, flesh firmness was untouched, suggesting the vapour acts mainly on outer tissues.

Perhaps the most striking finding is what the oil did not do. Neither BEO concentration nor its interaction with storage time significantly altered pH, acidity, total sugars, reducing sugars, or soluble solids, meaning the treatment left core respiratory and carbohydrate metabolism essentially intact. Biochemical analyses told a similar story: total phenolic content declined and total flavonoid content rose with ripening, exactly as expected, with no meaningful BEO effect. Antioxidant activity measured by the DPPH assay fell gradually while ABTS activity held steady through mid-storage before declining, a divergence the authors attribute to the different chemical classes each assay detects, with lipophilic antioxidants such as carotenoids depleting earlier than hydrophilic phenolics. Principal component analysis confirmed that samples clustered by storage time rather than by treatment, reinforcing that ripening progression, not basil vapour, dictated the fruit’s internal chemistry.

On the disease front, the results were sobering. Inoculated control mangoes developed anthracnose lesions averaging 3.99 square centimetres after seven days, and fruit treated with 500 microlitres per litre of BEO vapour showed only a 10.78 percent reduction in lesion area, an effect that was not statistically significant. The authors attribute this limited efficacy to the biology of Colletotrichum, which establishes infections inside host tissues before symptoms appear, placing the pathogen beyond the reach of surface-acting volatiles. The volatile constituents, including beta-cis-ocimene, linalool, and eucalyptol, are generally fungistatic rather than fungicidal, slowing lesion expansion without preventing infection, and their high volatility means they dissipate quickly from perforated storage containers, undermining sustained antifungal activity.

The study’s authors are candid about the implications. BEO vapour shows genuine potential as a natural treatment for modulating the visible and textural aspects of mango ripening, but it is insufficient as a standalone disease control measure. They argue that future progress lies not in simply cranking up the concentration, which risks phytotoxic damage and greater weight loss, but in smarter delivery: controlled-release packaging materials, encapsulation systems, and modified ventilation designs that keep volatile compounds at effective levels throughout storage. Combining basil vapour with complementary preservation strategies could also enhance both shelf life and disease management.

For a fruit industry worth tens of millions of dollars and for consumers increasingly wary of chemical residues, the message is one of cautious optimism. A kitchen herb’s fragrance can nudge a mango’s ripening clock and preserve its appearance a little longer, but the invisible fungus lurking within the peel demands more than vapour alone. The study adds a valuable piece to the growing science of vapour-phase natural preservatives, demonstrating that what matters in non-contact treatments is not just what is in the oil, but what actually reaches the air around the fruit, and for how long.

Subject of Research: Effects of vapour-phase Thai basil essential oil on postharvest ripening quality and anthracnose development in mango fruit

Article Title: Vapour-phase Thai basil essential oil and its effects on postharvest quality of ‘Nam Dok Mai Si Thong’ mango

Article References: Tangpao, T., Chung, H.-H., George, D. R., Suksathan, R., Sommano, S. R., Khemacheewakul, J., Wongkaew, M., & Sunanta, P. (2026). Vapour-phase Thai basil essential oil and its effects on postharvest quality of ‘Nam Dok Mai Si Thong’ mango. BMC Agriculture, 2(1), Article 32. https://doi.org/10.1186/s44399-026-00057-7

Image Credits: AI Generated

DOI: 10.1186/s44399-026-00057-7

Keywords: mango, Thai basil, essential oil, postharvest, anthracnose, Colletotrichum, ripening, volatile compounds, estragole, food preservation, shelf life, natural preservatives