Evaluation of the Physical, Chemical, Technological, and Sensorial Properties of Extrudates and Cookies from Composite Sorghum and Cowpea Flours.

In recent years, there has been a growing demand for gluten-free and functional products, driven by consumer preferences for healthier and more diverse food choices. Therefore, there is a need to explore new ingredients that can be used as alternatives to traditional gluten-containing grains. Thus, this work evaluated the physical, chemical, technological, and sensorial properties of extrudates and cookies from composite tannin sorghum (rich in resistant starch) and white cowpea flours. Extrudates and cookies were produced from a composite flour made of sorghum and cowpea, at a sorghum:cowpea flour ratio of 70:30, 50:50, and 30:70. Then, raw flours, cookies, and extrudates were characterized (dietary fiber, resistant starch, proteins, antioxidant capacity, pasting properties, etc.). Results obtained for particle size distribution and bulk density indicated that the particles increased and the color changed with the addition of cowpea flour. The raw tannin sorghum flour had a higher resistant starch concentration (36.3%) and antioxidant capacity (211.2 µmolTE/g), whereas cowpea flour had higher levels of proteins (18.7%) and dietary fiber (20.1%). This difference in the raw flour composition contributed to the nutritional value of the extrudates and cookies, especially the cookies which undergo dry heat and had higher retention of resistant starch and antioxidants. Moreover, sorghum flour presented a higher tendency to retrograde (high setback), which was decreased by the addition of cowpea flour. Overall acceptance and intention to purchase were higher for extrudates with 100% sorghum flour (6.52 and 68.3%, respectively) and cookies with 70% cowpea flour (7.03 and 76.7%, respectively). Therefore, nutritious and functional gluten-free extrudates and cookies, of good acceptability, can be produced from composite tannin sorghum and white cowpea flours.

Towards Sustainable and Nutritionally Enhanced Flatbreads from Sprouted Sorghum, Tapioca, and Cowpea Climate-Resilient Crops.

This study aimed to develop high-quality flatbreads for low-income countries by using composite flours from climate-resilient crops, i.e., sprouted sorghum, tapioca, and cowpea, as partial alternatives to imported wheat. Through the experimental design, several flatbread prototypes were developed that maximized the content of sprouted sorghum and cowpea flours and minimized the content of wholewheat flour. Three of them were chosen based on the best textural, nutritional (highest intake of energy, proteins, and micronutrients-iron, zinc and vitamin A), and economic (cheapest in Sierra Leone, Tanzania, Burundi, and Togo) features. The physicochemical properties, in vitro starch digestibility, total phenolic content, antioxidant capacity, and sensory acceptability were also measured for the samples. The experimental flatbreads showed lower rapidly digestible starch and higher resistant starch contents than the control (100% wholewheat based), and were also richer in phenolic content and higher in antioxidant activity. Moreover, one of the prototypes was perceived to be as acceptable as the control for texture and flavour properties. The ranking test, performed after explaining the nature of the samples, revealed that the flatbread meeting the nutritional criteria was the preferred one. Overall, the use of composite flour from climate-resilient crops was proven to be an efficient strategy to obtain high-quality flatbread.

Baking Process Effects and Combined Cowpea Flour and Sorghum Bran on Functional Properties of Gluten-Free Cookies.

Gluten-related disorders, including celiac disease and non-celiac gluten sensitivity, are growing worldwide. The only treatment for both disorders is a lifelong gluten-free diet. However, gluten-free foods are generally poorer in nutrients, less healthy, and have a high cost. Sorghum and cowpea are gluten-free grains with high levels of phenolic compounds (PC) and a low cost. Their phenolic profile is structurally different; thus, the blend of both can provide synergistic/complementary health benefits to the final product. This study analyzed the effect of baking process and the blend of cowpea flour (CP) and sorghum bran (SB) on the levels of PC, resistant starch (RS), neutral detergent fiber (NDF), and antioxidant capacity (AC) of gluten-free cookies. Eleven rice or cowpea cookie formulations were made with or without white sorghum bran (WSB) or black sorghum bran (BSB). Baking increased the extractability of PC, AC, and the NDF of almost all formulations. The PC and AC were, respectively, about twice and 3-5 times higher in cookies containing BSB compared to the others. There was a minor effect of WSB on the PC and AC. Although there were losses, the retention of RS of cookies after the baking process was between 49.8 and 92.7%. Sorghum bran has excellent potential for use as a functional ingredient in healthy food production. The combined CP and SB have great potential to improve the nutritional and functional properties of gluten-free products, especially the PC, RS, and NDF contents.

Dry Heating of Cowpea Flour below Biopolymer Melting Temperatures Improves the Physical Properties of Bread Made from Climate-Resilient Crops.

Improving the technological functionality of climate-resilient crops (CRCs) to promote their use in staple foods, such as bread, is relevant to addressing food and nutrition security in Africa. Dry heating of cowpea flour (CPF) was studied as a simple technology to modulate CPF physicochemical properties in relation to bread applications. For this purpose, the melting behavior of cowpea starch and proteins in CPF was first studied and modeled using Flory-Huggins theory for polymer melting. Next, dry-heating conditions were investigated based on the predicted biopolymer melting transitions in CPF to be well below starch and protein melting. The pasting properties (i.e., peak viscosity, final viscosity, breakdown and setback) of CPF could be selectively modulated depending on temperature-time combinations without altering the thermal behavior (i.e., melting enthalpies) of CPF. Water-binding capacity and soluble solids decreased with the increased severity of the temperature-time combinations. Dry-heated CPF added to CRC-based bread significantly improved crumb texture. In particular, dry heating at 100 °C for 2 h provided bread with the highest crumb softness, cohesiveness and resilience. The positive effects on the crumb texture could be largely related to enhanced starch integrity, as indicated by a reduction in breakdown viscosity after treatment. Overall, dry heating of CPF under defined conditions is a promising technology for promoting the use of CPF as a techno-functional and protein-rich ingredient in bread-type products.

Chemical, mineral composition, and sensory acceptability of cocoyam-based recipes enriched with cowpea flour.

The study was conducted to improve cocoyam-based recipes (steamed cocoyam paste [ebiripo], ikokore, and fried cocoyam balls [ojojo]) using different blends of cocoyam and cowpea flours (100:0, 80:20, 70:30, 60:40, and 50:50). The proximate composition, mineral composition, and sensory qualities of the recipes were determined using standard analytical procedures. The recipes had significantly (P < 0.05) higher contents of protein, fat, crude fiber, iron, zinc, sodium, and phosphorus compared with the control recipe (100% cocoyam flour). The protein content was highest in all recipes containing 50:50 cocoyam: cowpea flour (10.79%, 10.56%, 10.36% for ojojo, ikokore, and ebiripo, respectively). However, ikokore had higher iron (2.5 mg), phosphorus (92.5 mg), and zinc (1.92 mg) contents than ebiripo and ojojo. While the 80:20 recipe for ebiripo had significantly (P < 0.05) higher flavor and overall acceptability scores compared with other recipes. In conclusion, enrichment of cocoyam-based recipes with cowpea flour improved the proximate composition, mineral composition, and sensory acceptability of the foods.