Production of single cell protein by a local Trichoderma reesei in solid state fermentation: effects of process variables

Abstract

Single cell protein (SCP) has attracted a lot of attention as an alternative protein source to support the increasing demand and to reduce the dependence on fishmeal in the animal feed and poultry industries. The SCP can be produced using lignocellulosic materials which are abundantly generated continuously as agricultural residues by Trichoderma reesei in solid state fermentation system. In this work, we evaluated the effects of various carbon sources (rice straw, corncob, bagasse, and coffee husk) which were combined with various nitrogen sources (Urea, Ammonium Sulphate, NPK) on SCP production. The rice straw and coffee husk gave a higher SCP yield when combined with urea or NPK at C/N ratio of 20:1 and 30:1. The solid substrate which contained rice straw or coffee husk gave a higher SCP yield when combined with urea or NPK at C/N ratio of 20:1 and 30:1. The initial moisture content of the solid substrate gave a significant contribution to the SCP yield, the highest yield of SCP developed in the substrate with the initial water content of 75%. On the other hand, the ratio of inoculum size to the solid substrate of 1:1 (w/v) gave the maximum SCP yield.