Vol-1 Issue-2 2015 IJARIIE-ISSN(O)-2395-4396 1133 www.ijariie.com 58 PRODUCTION OF ACETIC ACID FROM MOLASSES BY FERMENTATION PROCESS Rutu Patel 1 , Hiral N. Pandya 2 1 Rutu Patel, Masters Fallow, Chemical Engineering Department, L.D.C.E., Gujarat, India. 2 Hiral N. Pandya, Assistant Professor, Chemical Engineering Department, L.D.C.E., Gujarat, India. ABSTRACT Acetic acid also called ethanoic acid is organic compound. Acetic acid produced via fermentation. Its pathway is conversion of glucose to ethanol and ethanol to acetic acid. In first step, Saccaromyces cerevesiae (yeast) converts fermentable sugar of molasses into ethanol and carbon dioxide. In second step, acetobacter aceti (acetic acid bacteria) converts ethanol into acetic acid and water. After completing process, the separation of product is carried out via centrifugation. Mixture of acetic acid and water is separated by distillation. In this report, details regarding cultures (micro-organism) have been used for the process is discussed. In practical laboratory work, ethanol fermentation and acetic acid fermentation have been carried out and it’s optimum parameters (pH, temperature, sugar concentration, and ethanol concentration) have been decided, which is discussed in detail. The kinetic study also have been done is mentioned. Key words: Saccaromyces cerevesiae, acetobacter aceti, micro-organism, fermentable sugar 1. FERMENTATION The term “fermentation” comes from a Latin word fermentum(to ferment). Fermentation is described as the process in which chemical changes occur in an organic substrate as the result of action of microbial enzymes. The product can either be:  The cell itself: referred to as biomass production.  A microorganisms own metabolite: referred to as a product from a natural or genetically improved strain.  A microorganisms foreign product: referred to as a product from recombinant DNA technology or genetically engineered strain, i.e. recombinant strain. All microorganisms need for their microbial activity the presence of several nutrients. 1.1 Micro-organisms involved in the fermentation The organisms involved in production usually grow at the top of the substrate, forming a jelly like mass. This mass is known as 'mother of vinegar'. The mother is composed of both acetobacter and yeasts, which work together. The principal bacteria are Acetobacter aceti. The main yeasts are Saccharomyces cerevisiae. It is important to maintain an acidic environment to suppress the growth of undesirable organisms and to encourage the presence of desirable acetic acid producing bacteria. Although a variety of bacteria can produce acetic acid, mostly members of Acetobacter, Gluconacetobacter, and Gluconobacter are used commercially. 1.2 Acetic acid fermentation Production of acetic acid can be carried out by aerobic and anaerobic fermentation. Anaerobic process is one stage process carried out by Clostridium. Aerobic fermentation is two stage processes. Glucose is converted into ethanol by S.cerevesiae. And second stage is ethanol is converted into acetic acid by acetobacter aceti. The fermentation is usually initiated by yeasts which break down glucose into ethyl alcohol with the liberation of carbon dioxide gas. Following on from the yeasts, acetobacter aceti oxidise the alcohol to acetic acid and water. Yeast reaction: C 6 H 12 O 6 → 2CO 2 + 2CH 3 CH 2 OH Glucose ethanol