Production of single cell proterin from brewery spent grains

Abstract

The production of single cell protein (SCP) by the propagation of the yeast, Saccharomyces cerevisae obtained from the Federal Institute of Industrial Research  Oshtxli was studied by using the extract of spent grains obtained from the International Beer and Beverage Industries, Kacltuia, Nigeria as a substrate in a medium which was also supplemented with other essential nutrients at a temperature of 30°C, pH of 4.6, air flow rate of l.2 scf/h and agitation rate of 200rmpm for 15h in a bench scale laboratory fermenter. Seed cultures for each of the three experimental fem1entation runs A, B, C undertaken belong to the first, second and third  generations respectively. The specific growth rate of SCP obtained for each of the rwis were determined to be 0.088h^-1 0.090h^-1 , 0.093h^-1 whilst the  corresponding doubling times were dt:tem1ined to be 7.88h, 7. ?Ohr, 7.45h. The specific growth rate values fall within the range of 0.07-0.1 J h^-1 reported for most strains of Saccaromyces cerevisiae. The yield of yeast from each of the runs were detennined to be 0.85, 0.875 and 0.90 whilst the corresponding protein contents were also determined be 49%, 52.5% and 54.25%. The observed increase in the specific growth constants, yield and protein content and the decrease of the  doubling times for the successive generation of yeast suggest an increase in the adaptation of the cells to the media from generation to generation.