Enrichment of protein content in cassava (Manihot esculenta Crantz) by supplementing with yeast for use as animal feed

The aim of this investigation was to study the kinetics of yeast S. cerevisiae growth in different media and to study the enrichment of cassava chip by fermentation using yeast. Experiment was conducted according to a 2x4 factorial arrangement in a Completely Randomized Design (CRD) to study growth kinetics of Baker’s yeast (YB) and Brewer’s yeast (YC) cultivated in 4 media with following composition: (urea:molass:water) = 40:32:100 (M1), 48:24:100 (M2), 56:16:100 (M3), 64:08:100 (M4) at pH 3.5-5.0 at 27°C for 120 h. The kinetic data of yeast growth were collected at 0 and every 6 h post-cultivation. All treatments were selected from the optimum cultivation time (66 h) mixed with cassava chip at ratio of 1 ml:1.3 g. For yeast fermented cassava chip protein (YEFECAP) products were analyzed for proximate composition. The results showed that kinetic growth of S. cerevisiae in YBM3 was the highest in number (3.0 x 10^11 cell/ml) at 66 h post-cultivation. However, YEFECAP production in YBM4 (Baker’s yeast with urea: molasses: water at ratio 64:08:100 (M4)) was highest in protein content at 47.5% crude protein CP when compared to other treatments. Furthermore, further research is required to study the use of YEFECAP as a protein source to replace soybean meal in in vivo feeding trials especially in productive ruminants.