Production of commodity chemicals requires
simple and robust processes providing high and
reproducible product yields. Microbial fermenta-
tions are by nature characterized by low produc-
tivity because of their sensitivity to a number of
factors, hence their optimization and intensifica-
tion are necessary to make them suitable for
industrial purposes. In the case of lactic acid
bacteria, it has been observed that changes in
growth conditions can alter the homofermentative
mode of metabolism to a heterofermentative one,
or lead to the change in the ratio of L- and
D-isomeric forms of the lactate produced. Lactate
containing predominantly the L-isomer is the de-
sirable product.