The research, published in Food Science & Nutrition, examined three teff varieties from the Ethiopian Institute of Agricultural Research’s Debrezeit Agricultural Research Center: Bora, a very white grain; Jitu, a pale white variety; and Filagot, a red-grained type. Each variety was milled using a local attrition milling method and then fractionated through standard laboratory test sieves into three size classes: a coarse fraction between 260 and 360 micrometers, a middle fraction between 160 and 260 micrometers, and a fine fraction between 90 and 160 micrometers. Particles larger than 360 micrometers and smaller than 90 micrometers were removed, giving the researchers tightly controlled flour fractions to work with.

The first striking finding concerned bulk density, a property that matters enormously to food manufacturers because it determines how much flour fits into a given volume and how it packs during storage and transport. As particle size decreased from the coarsest to the finest fraction, bulk density rose from 0.72 to 0.86 grams per milliliter. The explanation is geometric: smaller particles nestle into the pore spaces left between larger ones, reducing porosity and increasing compaction. Variety also mattered, with the red Filagot flour reaching the highest bulk density at 0.83 grams per milliliter, compared with 0.74 for the white Bora variety. Similar patterns have been reported for other milled products, including sugar beet powder, whose bulk density climbed as particles shrank.

Flow behavior told the opposite story. Using the funnel method, the researchers measured the angle of repose, the natural slope a conical heap of flour forms when poured onto a flat surface. Finer flours produced steeper heaps: the angle rose from 37.40 degrees for the coarsest fraction to 41.80 degrees for the finest. This happens because smaller particles have more surface area per unit mass, giving cohesive surface forces and friction more opportunity to act and making the powder stickier and harder to move. For engineers designing hoppers and conveying systems, the implication is practical and important: the inclination of a hopper must exceed the flour’s angle of repose to keep material flowing without clogging, so finer teff flours will demand steeper equipment geometries.

Color measurements on the Hunter L, a, b scale revealed a subtle but consistent relationship between particle size and appearance. Lightness values increased as particles got smaller, rising from 66.88 for the coarsest fraction to 68.73 for the finest, while redness and yellowness values both fell. The researchers attribute this to the fine, homogeneous pores of smaller particles, which absorb less light and reflect more, making the flour appear lighter and less saturated. Variety effects were even more pronounced: the white Bora flour scored the highest lightness at 70.29, while the red Filagot flour scored lowest at 64.74 and showed the highest redness value, a consequence of pigments from the grain’s seed coat dispersing through the flour during milling. In terms of color alone, the finest fraction was judged the most desirable, being lighter and less reddish than its coarser counterparts.

Mineral analysis added a nutritional dimension to the varietal comparison. The red Filagot variety significantly outperformed its white relatives, delivering 132 milligrams of calcium, 14.31 milligrams of iron, and 4.14 milligrams of zinc per 100 grams of flour, roughly double the iron content of the Bora variety. This aligns with earlier findings that red teff tends to be richer in iron than white types. Intriguingly, particle size had no significant effect on mineral content, meaning that milling finer does not dilute the grain’s micronutrient profile. The minerals were evenly distributed across fractions, so processors can pursue fine milling for functional benefits without sacrificing nutritional value.

The sensory heart of the study came when the flours were transformed into cookies using a standard formulation of teff flour, sugar, shortening, salt, baking soda, and water, baked at 190 degrees Celsius for 18 minutes. Thirty trained panelists, drawn from food science and food technology departments, evaluated the cookies within 24 hours of baking on a seven-point hedonic scale covering color, texture, crispness, taste, flavor, and overall acceptability. The results were unambiguous: finer flour made better cookies. Samples made from the 90 to 160 micrometer fraction scored highest on nearly every attribute, with overall acceptability reaching 6.00, compared with just 4.90 for cookies made from the coarsest flour.

Crispness showed one of the most compelling particle-size relationships. Cookies baked from the finest flour earned a crispness score of 6.51, while those from the coarsest flour managed only 5.74. The researchers explain this through starch damage and surface area: smaller particles present more surface to the dough matrix, producing a thinner, more brittle structure that fractures cleanly rather than deforming during chewing. As particle size increases, the force and energy required to break the cookie rise, making samples harder and less crispy. Variety mattered too, though differently across attributes. Bora cookies dominated in color, texture, taste, flavor, and overall acceptability, scoring 6.35 overall, while the red Filagot cookies lagged at 4.43, likely penalized by their darker color, which lowered consumer preference despite the variety’s superior mineral content.

The study’s broader significance lies in what it means for teff’s global future. Despite an exceptional nutritional profile, complete with all essential amino acids and more lysine and vitamins than most other cereals, teff remains largely confined to Ethiopia, and industrial processing of the grain is still in its infancy. By demonstrating that variety and particle size jointly govern flour behavior and consumer acceptance, the research gives millers and bakers a concrete parameter to optimize. The finest fraction, 90 to 160 micrometers, combined favorable flow characteristics for handling with the best sensory outcomes in the baked product, while the white Bora variety proved the strongest candidate for consumer-facing products. The panelists’ scores spanned the full hedonic range, from a low of 4.00, meaning neither like nor dislike, for coarse Filagot cookies up to 7.00, meaning liked very much, for fine Bora cookies, a spread that underscores just how much processing decisions can shape the fate of a single ingredient.

For a grain that has sustained Ethiopian communities for millennia, these findings offer a roadmap for wider adoption. Gluten-free markets are expanding rapidly as consumers seek alternatives to wheat, and teff brings antioxidant properties and a complete amino acid profile that few competitors can match. The lesson from this research is that nutrition alone will not win over global palates; the physical craft of milling, the size of each particle, and the choice of variety all converge to determine whether a teff cookie delights or disappoints. With the right combination of fine milling and light-colored grain, this ancient Ethiopian staple may finally be positioned to take its place on bakery shelves worldwide.

Subject of Research: Effect of teff flour variety and particle size on flour physicochemical properties and gluten-free cookie sensory quality

Article Title: Impact of Particle Size on Flour Physicochemical Properties and Cookies Sensory Acceptability Made From Teff (Eragrostis tef (Zucc.) Trotter)

Article References: Boka, A. L., & Tolesa, G. N. (2026). Impact of Particle Size on Flour Physicochemical Properties and Cookies Sensory Acceptability Made From Teff ( Eragrostis tef (Zucc.) Trotter). Food Science & Nutrition, 14(10), Article e72432. https://doi.org/10.1002/fsn3.72432

Image Credits: AI Generated

DOI: 10.1002/fsn3.72432

Keywords: teff, flour particle size, gluten-free cookies, bulk density, angle of repose, sensory evaluation, food color, mineral content, Ethiopia, food processing, Eragrostis tef, baking quality

The research team set out to answer a question that has long frustrated agricultural scientists in East Africa: while drought receives most of the attention in Ethiopia, waterlogging affects substantial areas of farmland, particularly in the high-rainfall zones and vertisol-dominated plains where drainage is naturally poor. When soils become saturated, oxygen is driven out of the root zone, and crops such as wheat, teff, and maize suffer from hypoxic stress that reduces nutrient uptake, stunts growth, and can ultimately destroy an entire season’s harvest. Unlike drought, which announces itself with visible wilting, waterlogging damage is often subtle at first, making it easy for farmers and policymakers alike to underestimate its cumulative toll.

Using a suite of agrohydrological models, the researchers simulated the water balance of Ethiopian croplands, tracking rainfall inputs, soil moisture dynamics, evapotranspiration, and drainage across representative growing areas. The analysis drew on long-term climate records, soil property datasets, and crop distribution information to identify hotspots where saturation events coincide with sensitive crop growth stages. The modeling framework allowed the team to distinguish between the effects of total rainfall amounts and the timing and intensity of rainfall, a critical distinction because even regions with moderate annual precipitation can experience damaging waterlogging if heavy rainfall episodes cluster during planting or early growth periods.

The results confirmed that waterlogging risk is not uniformly distributed across the country. High-elevation areas with flat topography and heavy clay soils, including parts of the Ethiopian highlands, emerged as particularly susceptible because their vertisols swell and seal when wet, preventing water from draining away. In these zones, the model simulations showed that prolonged saturation during critical phenological stages can substantially reduce yields, with the magnitude of losses depending on how long the root zone remains oxygen-depleted. The study’s quantitative estimates provide a baseline that had been missing from Ethiopia’s agricultural planning discussions, which have historically centered almost exclusively on water scarcity.

Climate change adds an urgent dimension to these findings. Projected shifts in rainfall patterns across the Horn of Africa include increased intensity of individual rain events even in regions where total annual precipitation may not change dramatically. More intense bursts of rainfall raise the likelihood of short-term waterlogging episodes that coincide with vulnerable crop stages. The researchers emphasize that this means climate adaptation strategies in Ethiopia cannot focus on drought resilience alone; a comprehensive approach must simultaneously address too much water as well as too little.

Turning to mitigation, the study evaluated a range of interventions through the same agrohydrological lens. Surface drainage systems, including furrows and raised beds, emerged as effective tools for removing excess water quickly from fields before root-zone oxygen depletion becomes severe. Broad bed and furrow systems, which have a long history of traditional use on Ethiopian vertisols, allow farmers to cultivate wet clay plains that would otherwise be too saturated to plant. The modeling showed that well-designed drainage can shorten the duration of saturation events substantially, protecting crops during their most sensitive growth windows.

The researchers also examined the role of agronomic practices that complement physical drainage. Adjusting planting dates to avoid the peak of waterlogging risk, selecting crop varieties with greater tolerance to saturated soils, and improving soil structure through organic matter amendments all contributed to reducing simulated losses in the model scenarios. Because Ethiopian smallholder farmers often operate with limited capital, the appeal of these lower-cost, management-based interventions is significant. The study’s framework allows the effectiveness of each measure to be compared under local soil and climate conditions, helping extension services prioritize recommendations rather than offering generic advice.

One of the study’s most important contributions is methodological. By coupling hydrological simulation with crop response functions that explicitly represent oxygen stress in the root zone, the researchers created a transferable analytical toolkit that can be applied beyond Ethiopia to other regions where waterlogging constrains agriculture. The approach demonstrates that national agricultural risk assessments should treat the full water balance, not just water deficits, as a driver of yield variability. This reframing has implications for investment decisions, as drainage infrastructure and waterlogging-tolerant breeding programs compete for funding against irrigation and drought-resilience projects that have traditionally dominated the agenda.

The implications for food security in Ethiopia are considerable. The country’s agricultural sector supports the livelihoods of the large majority of its population, and yield losses from waterlogging compound the pressures already imposed by droughts, soil degradation, and a rapidly growing population. By pinpointing where and when waterlogging is most damaging, and by demonstrating which interventions deliver the greatest protection, the study gives Ethiopian policymakers and development partners a concrete evidence base for targeting adaptation resources. The researchers suggest that integrating waterlogging risk into national land-use planning, extension curricula, and climate adaptation strategies would represent a meaningful step toward more resilient farming systems.

As extreme rainfall events become more frequent across East Africa, the silent toll of saturated soils is likely to grow. This study makes the case that the era of treating waterlogging as a secondary concern is over. With robust agrohydrological analysis now available, Ethiopia has an opportunity to act on both ends of the water spectrum, ensuring that its farms are prepared not only for the droughts that dominate the headlines but also for the floods of excess water that quietly drown their harvests from below.

Subject of Research: Agrohydrological analysis of waterlogging impacts and mitigation strategies in Ethiopian agriculture

Article Title: Agrohydrological analysis of waterlogging impacts and mitigation in Ethiopia

Article References: Wakjira, M. T., Molnar, P., Bartholomeus, R., Erkossa, T., & Descheemaeker, K. (2026). Agrohydrological analysis of waterlogging impacts and mitigation in Ethiopia. npj Sustainable Agriculture, 4(1), Article 74. https://doi.org/10.1038/s44264-026-00179-0

Image Credits: AI Generated

DOI: 10.1038/s44264-026-00179-0

Keywords: Ethiopia, waterlogging, agrohydrology, soil drainage, crop yields, vertisols, climate change, food security, sustainable agriculture, rainfall variability, drainage systems, smallholder farmers

The review’s scientific foundation rests on the mechanics of CRISPR/Cas systems. CRISPR, originally discovered as a bacterial immune mechanism, relies on an RNA-guided endonuclease such as Cas9 that cuts DNA at sequences matching a designed guide RNA. When plant cells repair these targeted breaks, typically through non-homologous end joining, they generate small insertions or deletions that can knock out a gene. Alternative repair through homology-directed repair, and newer tools such as base editing and prime editing, allow precise nucleotide substitutions and more complex sequence changes without introducing foreign DNA. Crucially, many resulting edits fall into the SDN-1 and SDN-2 categories, which produce genetic changes often indistinguishable from natural mutations or conventional mutagenesis, a point with major regulatory implications.

The technology’s track record in African-relevant crops is now substantial. Editing the MusaDMR6 gene in banana has produced enhanced resistance to Banana Xanthomonas Wilt, one of the most destructive bacterial diseases in East and Central Africa, while CRISPR has also been used to permanently inactivate endogenous Banana Streak Virus sequences and delay fruit ripening through targeting of the MaACO1 gene. In cassava, edited lines show reduced susceptibility to cassava brown streak disease, which causes annual losses estimated at 100 million dollars in East Africa, and mutagenesis of the MeCYP79D1 gene has lowered toxic cyanogenic compounds in the roots. In maize, editing of the ARGOS8 gene has been associated with improved drought tolerance and yield stability under water-limited field conditions.

The disease burden these tools address is staggering. Striga, a parasitic weed, can wipe out between 30 and 100 percent of sorghum yields in affected fields in Kenya and Ethiopia, while maize lethal necrosis, first detected in Kenya in 2011, can destroy up to 90 percent of a crop. In wheat, CRISPR-based modification of resistance loci has generated lines with strong resistance to powdery mildew. Ethiopian researchers are pursuing editing of semi-dwarfing gene orthologs such as SbSD1 and TefSD1 in teff, a staple grain whose tendency to lodge under wind and rain constrains yields across the highlands. Multiplex editing, in which several genes are modified simultaneously, is highlighted as especially promising for complex traits such as drought tolerance and durable disease resistance, though it demands careful evaluation of pleiotropic effects.

Nutritional improvement represents a third major application. The review describes how CRISPR approaches have been investigated for raising iron, zinc, carotenoid and amino acid content across crops including rice, wheat, potato, sweet potato and tomato, strategies directly relevant to African diets dominated by starchy staples. Reducing anti-nutritional compounds, as demonstrated with cyanogenic glycosides in cassava, simultaneously improves food safety. The authors argue that these edits can be stacked with disease resistance and drought tolerance through multiplex editing, producing varieties that address several constraints at once without requiring farmers to change what they plant or eat.

Yet the pipeline from laboratory to farm remains bottlenecked at nearly every stage. Plant transformation and regeneration, the step in which edited cells are grown into whole plants, is inefficient or genotype-dependent in many African staple crops, including sorghum, teff, pearl millet, cowpea and enset. Delivery methods such as Agrobacterium-mediated transformation, particle bombardment and DNA-free ribonucleoprotein delivery each carry trade-offs in cost, efficiency and scalability. Off-target effects, though now well characterized and controllable through careful guide RNA design, still require empirical validation in each crop. High-throughput phenotyping, essential for confirming that edited alleles perform under real field conditions across diverse African agro-ecologies, remains scarce, and multi-location, multi-season trials are urgently needed.

Regulation is perhaps the decisive variable. The review contrasts product-based regulatory approaches in Argentina, Brazil, Japan and the United Kingdom with a fragmented African landscape. Kenya has emerged as a research leader with active gene editing programs, Nigeria has produced leading biosafety guidelines, and Ethiopia published new genome editing guidelines in 2025 that distinguish SDN-1-type edits without foreign DNA from transgenic events, while also approving biotech maize and cotton for commercial cultivation. The authors welcome these moves, noting that regulatory clarity is helping to shorten the so-called valley of death between research and deployment, but they caution that implementation across variety release committees, biosafety authorities and seed regulators still lags behind publication of the guidelines themselves.

Economics and intellectual property add further friction. Overlapping patents on editing systems, delivery technologies and edited traits create licensing costs and freedom-to-operate constraints that fall hardest on orphan crops such as teff, enset, finger millet and Bambara groundnut, where small markets rarely justify expensive licensing. More than half of African smallholders obtain seed through informal networks, meaning even a perfect edited variety must navigate weak seed multiplication, quality control and extension systems to reach farmers. The review also engages with critics, including some civil society organizations who argue gene editing is a costly distraction from agroecological approaches, and counters that editing should be complementary, guided by participatory varietal selection and farmer-defined priorities such as reduced lodging in teff and Striga resistance in sorghum.

The authors close with a set of priorities: harmonizing SDN-1 and SDN-2 regulatory pathways across the continent, strengthening biosafety and transformation infrastructure, applying artificial intelligence to guide RNA design, adopting pangenomics and machine learning, and expanding research on orphan crops like finger millet, cowpea and enset that underpin food security but remain under-studied. They also point to de novo domestication and epigenome editing as emerging frontiers. With coordinated investment from national governments, donors and public-private partnerships, the review concludes, gene editing can meaningfully contribute to a sustainable and climate-resilient agricultural transformation in Africa, provided the benefits ultimately reach the smallholder farmers who produce most of the continent’s food.

Subject of Research: Applications, opportunities and challenges of CRISPR-based gene editing for improving major and orphan food crops in Africa

Article Title: Gene editing applications, opportunities and challenges for crop improvement in Africa a review

Article References: Gene editing applications, opportunities and challenges for crop improvement in Africa a review. (n.d.). https://doi.org/10.1007/s44279-026-00780-4

Image Credits: AI Generated

DOI: 10.1007/s44279-026-00780-4

Keywords: CRISPR, gene editing, African agriculture, crop improvement, food security, cassava, banana, teff, maize, disease resistance, drought tolerance, regulation