Assessment of the Effect of Microbial Fermentation on Antinutrients and Protein Quality of Selected Cassava Leaf varieties

Abstract

The study aimed to determine the effect of fermentation using a previously identified isolate on antinutrients and protein quality of cassava leaves. The microorganism was previously isolated from a Kenyan spontaneously fermented milk product, Amabere amaruranu. The cassava leaves used were kibandameno and tajirika varieties which are considered sweet and bitter varieties respectively. They were fermented using a 5% inoculation level of 10⁶ CFU/ml of the Levilactobacillus brevis isolated strain. 50 grams of cassava leaves were fermented at different times (24, 48, 72, and 96 hours). The control was done without microbial inoculation. The samples were withdrawn after each of the hours and subjected to analysis of free cyanide and phytic acid content. There was a significant reduction in both antinutrients content after fermentation, with each remaining within the acceptable safe limit. Protein quality was determined in terms of crude protein content and in-vitro protein digestibility. The crude protein in both varieties ranged between 28% and 43%. The in-vitro digestibility was high ranging from 63% to 94% in all of the experimental samples. The results from this study conclude that fermentation using Levilactobacillus brevis reduced the antinutrients (phytic acid and cyanide) and improved the protein quality of the selected leaves varieties under investigation.