Protein quality and micronutrient availability of extruded corn, soy, sorghum, and cowpea fortified‐blended foods

Corn and soybean micronutrient fortified‐blended foods (FBFs) are commonly used for food aid. Sorghum and cowpeas have been suggested as alternative commodities because they are drought tolerant, sustainable, and not genetically modified. Our primary objective was to compare nutritional quality of new extruded FBFs with a current USAID corn and soy blend FBF, CSB+. A second objective was to compare protein quality of whey protein concentrate (WPC) FBFs to a soy protein isolate (SPI) FBF. Serena and Seredo sorghum‐cowpea, white sorghum‐cowpea with SPI or WPC, white sorghum‐soy, extruded corn‐soy blend, CSB+, and AIN‐93G were fed ad libitum to 21‐23 day old male weanling Sprague‐ Dawley rats (n=10) for 4 weeks. Food intake and weights were measured every other day and weekly, respectively. At study end, bone density and fat mass were assessed via PIXIMUS densitometer, and hemoglobin content of whole blood was later analyzed using Drabkin's reagent. Data were analyzed using ANOVA and Tukey's test. The CSB+ group had significantly less food intake, weight gain, caloric efficiency, and length, compared to all groups. Compared with AIN‐93G and WPC FBFs groups, the SPI FBF group had significantly lower caloric efficiency, and a non‐significant decrease and increase in growth and fat mass, respectively. There were no significant differences between WPC FBFs groups. Compared to new FBFs, CSB+ intake resulted in growth retardation. Outcomes in new FBFs were similar, and comparable to AIN‐93G. Our results suggest that SPI FBFs may be of inferior protein quality compared to WPC FBFs, and thus impair growth. Funded by USDA‐MFFAPP.