This Brief explores the importance of lactic acid and fermentation in
the modern food industry. Although it is usually associated with milk
and dairy products, lactic acid can also be found in many other
fermented food products, including confectionery products, jams, frozen
desserts, and pickled vegetables. In this work, the authors explain how
lactic acid is produced from lactose by Lactobacillus and Streptococcus
cultures, and they also emphasise its important role as pH regulator and
preservative, helping to the inhibition of microbial growth in fermented
foods. The Brief discusses a wide range of lactic acid's applications as
a natural additive, curing or gelling agent, flavour, food carrier,
solvent, and discoloration inhibitor, among others. Readers will also
find a brief overview of the current analytical methods for the
quantitative and qualitative determination of lactic acid in foods.