Lactic acid occurs naturally in many food products. It has been in use as an acidulant, preservative and pH regulator for quite some time. Lactic acid is non-toxic and is deemed "Generally Recognized As Safe" (GRAS). Some of the important applications of lactic acid in the food industry are detailed below.
Bakery Products: For direct acidification of certain breads, lactic acid is the natural sour dough acid. The general appearance of a loaf of bread is greatly improved by the use of bacterial lactic acid, a larger loaf results per weight of bread with improved bloom, and color of crust. Lactic acid is directly added to certain types of fermented dough crispy biscuits. Lactic acid added to dough increases the shelf life due to its retarding action on molds and rope.
Confectionery: Lactic acid finds use as an acidulant in the confectionery industry. It is a better acidulant than citric acid since the sugar inversion is less when used for hard boiled candies. It does not have the initial burst of flavor and tanginess of citric acid. Lactic acid imparts a mellow and lasting sourness. It enhances the flavor much more.
Meat and Meat products: Lactic acid is widely used in meat products as an antimicrobial agent. Decontamination of beef and poultry carcasses in slaughter house operations is practised to reduce Salmonella infection. Recent research, indicate the use of hot lactic acid spray on carcasses where reduction of over 99 % of E.Coli has been observed.
Dairy Products: Direct acidification with lactic acid, in dairy products such as cottage cheese, is preferred to fermentation as the risks of failure and contamination can be avoided. The processing time also can be saved. Lactic acid is also used as an acidulant in dairy products like cheese and yogurt powder.
Beverages: Lactic acid due to its mild nature is the acidulant of choice in delicately flavored soft drinks and fruit juices. It does not mask or over power the natural flavor. Its flavor enhancing property makes the beverage more palatable and leaves a lingering taste. Lactic acid is preferred over citric acid for these reasons
Olives and Pickles: Green olives and others are often packed in a solution of salt, lactic acid and water. The lactic acid acts as a preservative and improves the clarity of the brine and flavor. A mixture of acetic acid and lactic acid in pickled products such as onion, imparts a milder taste and flavor, and improves microbial stability.