A study of alcoholic fermentation of SAP from the bamboo oxytenanthera abyssinica (A. Rich) Munro

The study covered the following areas; 1. Determination of the amounts and types of fermentable sugars and types and amounts of alcohols in the fermented bamboo sap. 2. Monitoring of laboratory scale fermentation of the bamboo sap. 3. Isolation and identification of micro-organisms associated with alcoholic fermentation of the bamboo sap. 4. Studying the performance of microbial isolates from the bamboo sap in fermenting other substrates. In this study, the types and total amounts of fermentable sugars in fresh bamboo sap sampled at Ihemi (Iringa) Tanzania were determined by using an HPLC and the dinitrosalicylic acid method, respectively. The sap which made into a beverage called "ulanzi" by locals was found to contain glucose and fructose as the sole types of fermentable sugars and about 17. 65 % w/w total fermentable sugars. Gas chromatographic analysis has shown that 2.4 to 6.88% w/w ethanol is the sole detectable alcohol depending on stage of fermentation of the bamboo sap. Batch alcoholic fermentation of bamboo sap was characterised by rapid microbial activity during the first two days. This was followed by retardation in fermentation in the following days. This was manifested by sugar utilization, ethanol and carbon dioxide production accompanying pH decrease. The performance of bamboo sap yeast isolates in fermenting glucose, sucrose and molasses at varying conditions was studied. The yeast isolates were found to ferment glucose, sucrose and molasses to ethanol. About 9.2 to 10.24 % w/w ethanol was produced. The isolates were found to work optimally at 300 C and 25 % w/w initial sugar concentrations. Taxonomic identity and characterisation of yeast isolates was done by employing standard methods. The isolates were found to contain characteristics of Saccharomyees cerevisiae