Abstract

Cassava is made up of starch as its major nutritive reserve. Starch which is one of the most important products synthesized by plants is consumed as food and can be used in industrial processes. This investigation seeks to explore the availability of cassava as a source of glucose as well as poultry manure as a source of nitrogen in the production of yeast. Cassava flour was hydrolyzed with 0.5% (v/v) concentrated H₂SO₄ as carbon source for the production of yeast. It was found that pH 6.5 gave optimum yeast growth. Increased concentrations of acid-hydrolyzed cassava and poultry manure extracts led to significant (P < 0.05) increase in yeast biomass after 36 h culture. The residual glucose concentration was also determined and was found to be significantly (P < 0.05) increased with increase in the concentration of poultry manure extract. Therefore, yeast can be produced using acid hydrolyzed cassava flour as carbon source with poultry manure extract as nitrogen source. The methods described in this work can be used in the development of a rapid method of producing glucose and simple sugars from cassava through acid hydrolysis and combining this with poultry manure for yeast production.

Key words: Yeast, poultry manure extract, acid-hydrolyzed cassava.