Some observations on the performance of Aspergillus t oryzae and Saecharomyces cerevisiae in the manufacture of Rice vinegar

Abstract

Vinegar is the liquid produced from a suitable raw material containing starch or sugar or starch and sugar by the process of double fermentation, alcoholic and acetous, and which contains at least 4% w/v acetic acid. Rich vinegar is grain vinegar, which has over 4.2% acidity as acetic acid. Vinegar is used as a flavoring and preservative to make some ketchups, sauces and chopped pickles. To make rice vinegar rice, yeast, culture of Aspergillus oryzea and water are used. Variety of Bg 358 is used as the rice. Aspergillus oryzea, Saccharomyces cerevisiae and Acetobacter aceti are involved in the manufacture of rice vinegar. First of all by giving anaerobic condition two samples were prepared by adding steamed rich,culture of Aspergillus oryzea, water and yeast. One of the sample was kept in room temperature and other was kept in cold room at 150C. Another experiment was carried out by giving same environment. But yeast wasn’t added to the maehrduring the activity e f-Aspergillus oryzea. Yeast was added at the-initiation stage of the alcoholic fermentation. Another experiment was carried out by giving aerobic condition. In this stage too yeast was added at the initiation stage of the alcoholic fermentation. Here increase in brix value was observed due to the performance of Aspergillus oryzea.Alcoholic fermentation was carried out by using Saccharomyces cerevisiae. Acetobacterbacteria was used in acitic acid fermentation, to convert ethanol in to acetic acid. Aerobic condition was used at this stage. Quality of the water is very important in whole fermentation process. The produced rich vinegar total acidity as acetic acid 4.5%. Oxidation value was 952 . Alkaline oxidation value was 40. loding value was 360 and Formol value was 0.5 According to the vinegar analytical values and statiscally analyzed data the produced rice vinegar is with good quality attributes. So can introduce this produce rice vinegar successfully in to the competent vinegar market.