Retention and bioaccessibility of B‐carotene (BC) in biofortified cassava

Cassava root represents a primary caloric source for many rural African communities despite its very low content of βC. Roots from wild type (WT, 0.9 μg βC/g DW) and transgenic lines with increased βC (22, 29 and 30 μg βC/g DW) were cooked according to traditional styles to assess retention. Mean relative retention of βC in root from biofortified lines after boiling (86%) and in fufu (wet fermentation + boiling; 93%) exceeded that for boiled WT cassava (67%) and WT fufu (83%). In contrast, retention of βC in gari (dry fermentation + roasting) was only 28% for both WT and transgenic cassava. Bioaccessibility of βC in cooked cassava was determined by simulated digestion. Efficiency of βC micellarization during digestion of WT boiled root, fufu and gari was 27, 31 and 28%, respectively, whereas micellarization during digestion of biofortified boiled root, fufu and gari was 34, 39 and 36%, respectively ( p <0.05). Caco‐2 cells were used to confirm the accessibility of micellarized βC. Apical uptake of micellar βC (as %) was independent of genotype and style of cooking. βC content in Caco‐2 cells incubated with micelles prepared from the biofortified cassava was approx. 65 times greater than in cells exposed to micelles generated during digestion of similarly cooked WT cassava. These results suggest that retention during cooking and bioaccessibility of βC in biofortified cassava root are proportionally greater than that in WT roots. Supported by the Ohio Agriculture Research And Development Center.