Comparative study on the fermentation of sato by mixed pure culture microorganism and yeast cake

Abstract

This research aimed to study the Sato fermentation process by way of a comparative study between a local wisdom process using yeast cake, and an experimental process using mixed pure culture microorganism of Aspergillus oryzae TISTR 3232, Amylomyces rouxii TISTR 3182, Hansenula anomala TISTR 5148, Saccharomyces cereviceae TISTR 5049. The experiment was conducted under 3 environment conditions at room temperature, controlled temperature at 25OC and underground temperature. Sato productions from the experiment were studied for variation of chemical properties and quantity of microorganisms during the 14 days of the fermentation process. Results from the study indicated that Sato products from mixed pure culture microorganism at any environmental condition yield higher alcohol content than those from yeast cake at all conditions. On ordering of temperature factors from room temperature, 25OC and underground, alcohol content of Sato from mix pure culture microorganism were 10.17%, 10.57% and 11.58%, better than Sato from yeast cake of 9.83%, 9.22% and 10.66%, respectively. The percentage of acidity of Sato from mixed pure culture microbe were 0.778%, 0.639% and 0.880%, lower than from yeast cake of 0.855%, 0.716% and 0.936%, respectively. Quantity of yeast after the ending of the production process was 6.9x107, 7.6x107 and 7.2x107 for mixed pure culture microbe higher than from yeast cake of 1.2x107, 8.6x106 and 2.8x107, respectively. Preliminary tests on sensory evaluation indicated a statistically significant difference at 95% confidence level, on acceptability level of the two products made from mixed pure culture microorganisms and yeast cake. Results from the study suggested that usage of mixed pure culture microorganism in Sato fermentation at the community level would ease control mechanisms, as well as reducing loss due to undesirable contamination during the fermentation process and could be applied for further development of Sato's quality.