Protein Enrichment of Potato Peels Using Saccharomyces cerevisiae via Solid-State Fermentation Process

Abstract

In order to add value to potato peels and also curb their environmental pollution problems, this study investigated the protein enrichment of potato peels with Saccharomyces cerevisiae via Solid-State Fermentation (SSF). SSF is a fermentation process which involves solid matrix and is carried out in absence or near absence of free water. SSF of potato peel mashed was carried out with S. cerevisiae at 30°C, pH of 5.5, moisture adjustment between 40 and 90%, addition of ammonium sulphate and urea salts as nitrogen supplements for the microorganisms for 3 days. The results showed that the percentage crude protein content of all the fermented samples increased significantly when compared with the unfermented sample. 40% moisture content adjustment and ammonium sulphate as nitrogen source gave the best result. The crude protein increased from 12.5% to 21.86%, which is 74.88% increment for ammonium sulphate supplementation, and 12.5% to 18.42%, which is 47% increment for urea supplementation. Therefore, the fermented peels could serve as good source of cheap protein enriched feed for livestock.