Evaluation of protein enrichment of waste potato and cassava with (Paecilomyces variotti)

Abstract

Problems in the protein supply call for alternatives to traditional sources. In this context, cell or single-cell microbial protein (SCP) is an appealing option. One of the advantages of SCP, is that use of industrial and post-harvest wastes, such as agro-industrial wastes (AWs). Within AWs are waste potato and cassava, which currently do not receive any treatment to add them value. A way of doing so is via protein enrichment from solid-state fermentation (SSF). In this work, we used potato and cassava residues as a source of carbon and energy, and assessed the effect of adding two types of nitrogen sources: ammonium sulfate (10 g/L) and peptone(10 g/L) and two levels of humidity (10 and 30%) through a 22 factorial design of experiments carried out for 24 days. The protein level was measured with the Biuret method after removal of the substrate’s protein. Our statistical analysis indicates that the combined effects were better than the simple ones: for potato residues, the highest protein enrichment was 166, 29 %, obtained from a combination of a humidity level of 30% and ammonium sulfate as nitrogen source. For cassava residues, the highest protein enrichment was 171.05 %, obtained from a combination of 10% moisture and peptone as nitrogen source peptone.