One of the oldest techniques for preserving food is drying. Dehydrating foods reduces their moisture content and increases their shelf life by preventing microbiological activity. Food placed on the ground to dry in the sun is a common sight in rural areas of low- and middle-income countries but requires a large amount of land and can lead to food degradation by overexposure to the sun, insects, and vermin. This study designed, fabricated, and evaluated the performance of a solar dryer in comparison to direct sun drying for efficiency and product quality, utilizing bananas and potatoes as representative foods. The dryer was produced and tested within the context of Bangladesh, unlike other commercial devices. With its mild steel frame, fan, solar collector, and DC battery, the dryer achieved a drying efficiency of 49.2% by reaching a drying chamber temperature of 71 °C, which is 30 °C higher than ambient. Drying times were decreased, and samples of potatoes and bananas reached equilibrium moisture content in 6 h as opposed to 9 h for direct sun drying. The moisture content of solar-dried foods was between 12 and 13 percent, making them appropriate for long-term storage. Bioactive substances such as phenolic content and DPPH scavenging activity were reduced by 18% and 21%, respectively, in comparison to direct sun drying. Quality assessments showed that there was little loss in color and nutrients for solar-dried samples. With a one-year payback period, an economic attribute of 3.26, and a life cycle benefit of BDT 310,651 (USD 2597.68), economics show the dryer’s feasibility. The solar dryer functioned faster than direct sun drying due to its significantly higher heat generation. The solar dryer was more efficient, effective, and economic within the context of Bangladesh and other low- and middle-income countries.

This study investigated the incorporation of mango peel dietary fiber (MPDF) extracted from two Bangladeshi mango varieties (Himsagar and Amrapali) into biscuit formulations to enhance nutritional quality and reduce agrowaste. Both the mango peels were analyzed for physicochemical properties, where Amrapali peels exhibited higher dietary fiber (9.15%) and oil absorption index (5.76–5.83 g/g), while Himsagar peels had higher protein content (3.7% vs. 3.5%) and a higher phenolic content (23.06 mg GAE/g). The crude fiber extracted from both varieties contained 46.52%–47.15% total fiber, with insoluble and soluble fractions of 28.02%–28.27% and 18.46%–18.88%, respectively. Both the MPDF exhibited similar morphologies such as complete, rough, porous, and loosened structures. Biscuits were prepared with 0%, 2%, 4%, 6%, and 8% MPDF substitution and analyzed for nutritional, physical, textural, and sensory attributes. Results showed a significant increase in crude fiber content (from 1.79% to 5.74%) and moisture content (from 7.48% to 9.93%) with increasing MPDF levels ( p < 0.05). Conversely, protein, fat, and ash contents decreased significantly ( p < 0.05). Firmness, stickiness, and strength of the biscuit dough were decreased significantly among the samples that indicating the dough became softer compared to control. Total phenolic content and antioxidant activity increased markedly, reaching 12.30 mg GAE/g at 8% MPDF. Hardness of biscuits increased as MPDF concentration rose from 2% to 8% in the biscuit samples. In addition, with the elevated levels of MPDF supplementation, there was a decrease in brightness, redness, and yellowness of biscuits. Biscuits with up to 6% MPDF maintained favorable sensory attributes while offering significantly increased dietary fiber and antioxidant content ( p < 0.05). The findings demonstrate the potential of MPDF as a sustainable, functional ingredient in bakery products, with 6% supplementation identified as the optimal level for balancing enhanced nutrition and consumer acceptability.

Peanut butter is a popular, versatile food spread globally known for its nutritional value and unique flavor. As consumer preferences evolve, there is an increasing demand for fortified products. Coconut flour and milk powder are potential fortification agents due to their nutritional benefits and compatibility with various food matrices. We explored the effects of incorporating coconut flour and milk powder into peanut butter, analyzing its nutritional composition and sensory qualities. Various combinations (0, 5, 10, and 15% w/w) of coconut flour, milk powder, and their mixture were introduced into peanut butter followed by a thorough physicochemical and sensory analysis. The results showed notable changes in both physical and chemical attributes. Coconut flour and its combination with milk powder increased the moisture content in peanut butter, while milk powder had the opposite effect. The protein content peaked in the peanut butter with 15% coconut flour, while the fat content diminished with higher concentrations of coconut flour and milk powder. Carbohydrate levels in the supplemented samples surpassed those of the control and commercial peanut butters. All the variants exhibited a pseudoplastic flow behavior, with coconut flour and milk powder concentrations affecting viscosity. The textural analysis revealed differences in oil separation, spreadability, and firmness, with 15% coconut flour yielding the highest firmness and oil separation. Noteworthy color changes were evident, particularly with the inclusion of 15% milk powder. Sensory assessments favored the peanut butter with a 15% blend of coconut flour and milk powder, while the color preference leaned towards the 15% milk powder variant. The consumers preferred the peanut butter fortified with a 15% blend of coconut flour and milk powder. Our research can help food manufacturers create healthier, more appealing products that cater to evolving consumer preferences and dietary requirements.

This research offers an in-depth comparative examination of the amino acid profiles and bioactive substances in two different varieties of mature wheat grains (Triticum aestivum) and the young shoots of wheatgrass BARI gom 33. The amino acid profiles were analyzed using high-performance liquid chromatography (HPLC) after performing acid hydrolysis. Standardized methods were utilized to assess the bioactive compounds present. The results revealed significant variations in the amounts of both essential and non-essential amino acids, as well as bioactive compounds, between wheat and wheatgrass. Notably, wheatgrass exhibited higher concentrations of essential and non-essential amino acids, including histidine, lysine, phenylalanine, isoleucine, methionine, valine, threonine, serine, alanine, and tyrosine. This indicates that wheatgrass may have potential as a nutrient-dense dietary supplement. Wheatgrass exhibited significantly elevated levels of total phenols at 235 mg GAE/100g, total flavonoids at 166.3 mg QE/100g, and DPPH inhibition activity (70 %) compared with the mature wheat grain. Nonetheless, this research offers important information regarding the nutritional makeup of wheatgrass and mature wheat, emphasizing their unique amino acid and bioactive compound profiles. These results carry considerable implications for the possible health advantages related to wheatgrass consumption.