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.

Autorentext
Sara M. Ameen is currently a Quality Control Chemist at the Medical Research Laboratories, Helwan University, Faculty of Science, Cairo, Egypt. After obtaining her Bachelor's Degree, Double Major in Chemistry and Zoology in 2010, and subsequent Postgraduate Diploma in Analytical Chemistry and Premaster Studies in Inorganic and Analytical Chemistry (2011 and 2012, respectively) at Helwan University, she worked as analytical chemist and documentation officer until 2013. Her current duties concern modification and validation of analytical procedures, development of experimental protocols, and other quality control-related responsibilities in the field of analytical chemistry.

Giorgia Caruso is currently a researcher in Food Microbiology at the "Istituto Zooprofilattico Sperimentale", Palermo, Italy. At present, she is also attending a four-year specialization in Clinical Microbiology and Virology at the Policlinico Paollo Giaccone Hospital, Palermo. Italy. After obtaining her Master's Degree in 2012, she started her career in Food Science as a researcher, focusing on foodborne pathogens (Shiga-toxin producing E. coli, Salmonella, Listeria) and food technology (shelf life extension techniques, food irradiation). She is an Editorial Board member of the International Journal of Trends and Technologies in Food Processing, and has also contributed as a reviewer for some journals, including the African Journal of Food Science and the African Journal of Microbiology Research. Giorgia Caruso has also contributed to the SpringerBriefs in Chemistry of Foods, Food Packaging Bulletin and other food-related journals.

Inhalt
The Importance of Lactic Acid in the Current Food Industry: An Introduction.- Chemistry of Lactic Acid.- Regulatory Importance of Lactic Acid in the Food and Beverage Sector.- Lactic Acid in the Food Matrix: Analytical Methods.- Lactic Acid and Lactic Acid Bacteria: Current Use and Perspectives in the Food and Beverage Industry.