Abstract

OPTIMIZATION, KINETICS AND QUANTIFICATION OF LACTIC ACID PRODUCTION BY ANAEROBIC DIGESTION OF VEGETABLE WASTE USING INDIGENOUS MICROORGANISMS.

D. Sailaja, Mohit Mishra*, Sunil Pande, Priyanka Guptad and  . Chandrasekhar 

ABSTRACT

Present work is an economic approach towards production of lactic acid in pure form from cheap agricultural by products. Optimization, quantification and kinetic parameter were evaluated for lactic acid production during anaerobic digestion of vegetable waste using the indigenous microbial population predominated by Lactobacillus acidophilus, Lactobacillus casei and E.coli. The fermentation was carried out at different dilutions (waste to water ratio) providing different initial total solids (TS) concentration (55-190 g/L) for a period of 3 days & parameters such as total dissolved solids, total suspended solids, pH, COD, carbohydrates, and protein were monitored. Acetic acid was the major organic acid produced; however, the lactic acid production was optimum at waste: water ratio of 1:1 on volume basis. Highest lactic acid (15-20 g/L) was produced at TS of 95 -100 g/L.

Keywords: organic acid, vegetable waste, total solids, hydrolysis, Lactobacillus acidophilus, L casei, E.Coli.