Sorghum-Insect Composites for Healthier Cookies: Nutritional, Functional, and Technological Evaluation

Protein-energy malnutrition (PEM) is a major health concern in sub-Saharan Africa (SSA). Relying on unexploited and regionally available rich sources of proteins such as insects and sorghum might contribute towards addressing PEM among at-risk populations. Insects are high in nutrients, especially protein, and are abundant in SSA. Sorghum is adapted to the tropical areas of SSA and as such it is an appropriate source of energy compared with temperate cereals like wheat. It is necessary to assess whether cookies fortified with sorghum and termite would be suitable for use in addressing PEM in SSA. Whole grain sorghum meal and termite meal were mixed at a 3:1 ratio (w/w sorghum:termite) to form a sorghum-termite meal blend. Composite cookies were prepared where the sorghum-termite blend partially substituted wheat flour at 20%, 40%, and 60% (sorghum-termite blend:wheat flour (w/w). The functional and nutritional qualities of the cookies were assessed. Compared with the control (100% wheat flour), the cookies fortified with sorghum and termite had about double the quantity of protein, minerals, and amino acids. However, with increased substitution level of the sorghum-termite blend, the spread factor of the cookies decreased. There is a potential to incorporate sorghum and termite in cookies for increased intake of several nutrients by communities that are vulnerable to nutrient deficiencies, especially PEM.

Nutritional Properties and Consumer's Acceptance of Provitamin A-Biofortified Amahewu Combined with Bambara (Vigna Subterranea) Flour

Amahewu is a fermented non-alcoholic cereal grain beverage, popular in Southern Africa. This study evaluates the possibility of producing an acceptable provitamin A (PVA)-biofortified maize amahewu, complemented with bambara flour, to contribute towards the alleviation of protein energy malnutrition (PEM) and vitamin A deficiency (VAD). Germinated, roasted, and raw bambara flours, were added at 30% (w/w) substitution level, separately, to either white maize or PVA-biofortified maize flour, and processed into amahewu. Wheat bran (5% w/w) was used as reference inoculum. Amahewu samples were analyzed for nutritional properties and acceptability. The protein and lysine contents of amahewu almost doubled with the inclusion of germinated bambara. Protein digestibility of amahewu samples increased by almost 45% with the inclusion of bambara. PVA-biofortified maize amahewu samples complemented with bambara were extremely liked for their color, aroma, and taste when compared with their white maize counterparts. The principal component analysis explained 96% of the variation and PVA-biofortified maize amahewu samples were differentiated from white maize amahewu samples. The taste of amahewu resulting from roasting and germination of bambara was preferred in PVA-biofortified maize amahewu, compared to white maize amahewu. We conclude that PVA-biofortified maize amahewu, complemented with germinated bambara, has the potential to contribute towards the alleviation of PEM and VAD.

Provitamin A retention and sensory acceptability of amahewu, a non-alcoholic cereal-based beverage made with provitamin A-biofortified maize

BACKGROUND

Vitamin A deficiency is a major public health problem in sub-Saharan Africa. Amahewu is a popular southern African lactic acid fermented non-alcoholic maize-based beverage, which is deficient in vitamin A. In this study, provitamin A retention and sensory acceptability of amahewu processed using provitamin A-biofortified maize and three types of inoculums during fermentation (malted maize, wheat bran and Lactobacillus starter culture) were investigated.

RESULTS

The total provitamin A content of amahewu samples, estimated as β-carotene, β-cryptoxanthin and α-carotene content, ranged from 3.3 to 3.8 g kg(-1) (dry weight). Provitamin A was substantially retained (79- 90% β-carotene equivalent) in amahewu after fermentation. Amahewu samples prepared with added starter cultures had the lowest retention of provitamin A. Consumers (approx. 69%) liked provitamin A-biofortified amahewu either moderately or very much. Principal component analysis of amahewu sensory data showed that 71% of variation was due to maize types and 18% of variation could be due to the inoculum used during fermentation. Amahewu samples prepared using provitamin A-biofortified maize were slightly more liked (mean score: 7.0 ± 1.2) compared to those of white maize reference samples. The use of starter culture combined with either malted maize or wheat bran as inoculum during fermentation improved the taste and aroma of amahewu and hence its acceptability.

CONCLUSION

Provitamin A is substantially retained in amahewu after fermentation. The slightly high acceptability of amahewu prepared using provitamin A-biofortified maize compared to that of white maize thus suggests that fermented product like amahewu can potentially be used to deliver provitamin A to vulnerable individuals.