Abstract: Methods for obtaining a carboxylic acid product from a lactose-containing feedstock include contacting the lactose-containing feedstock and a first mixture of microorganisms in a first bioreactor under anaerobic conditions at a temperature of about 45° C. to about 55° C. and a pH of from about 4 to about 6 for a period of time such that lactic acid is formed; contacting the lactic acid with a second mixture of microorganisms in a second bioreactor under anaerobic conditions at a temperature of about 25° C. to about 35° C. and a pH of from about 4 to about 6 for a period of time such that the lactic acid is converted to one or more C3-C12 carboxylic acid products; and isolating the one or more C3-C12 carboxylic acid products. The lactose-containing feedstock has a pH greater than 4.5.

Abstract: Methods for obtaining a carboxylic acid product from a lactose-containing feedstock include contacting the lactose-containing feedstock and a first mixture of microorganisms in a first bioreactor under anaerobic conditions at a temperature of about 45° C. to about 55° C. and a pH of from about 4 to about 6 for a period of time such that lactic acid is formed; contacting the lactic acid with a second mixture of microorganisms in a second bioreactor under anaerobic conditions at a temperature of about 25° C. to about 35° C. and a pH of from about 4 to about 6 for a period of time such that the lactic acid is converted to one or more C3-C12 carboxylic acid products; and isolating the one or more C3-C12 carboxylic acid products. The lactose-containing feedstock has a pH greater than 4.5.