Lactic acid #CAS50-21-5

Lactic acid #CAS50-21-5

Lactic acid (2-hydroxypropionic acid, CH3-CHOH-COOH) is the most widely occurring organic acid in nature. Due to its chiral a-carbon atom, lactic acid (LA) has two enantiomeric forms. Of these, L-(+)-lactic acid is more important in food and pharmaceutical industries because humans have only L-lactate dehydrogenase. The chemical behavior of lactic acid is mostly determined by the two functional groups. Besides the acidic character in aqueous medium, the bifunctionality (a terminal carboxylic acid and a hydroxyl group) allows lactic acid molecules to form ‘‘interesters’’ such as the cyclic dimers, the trimers, or longer lactic acid oligomers.
After its first isolation by the Swedish chemist Scheel in 1780 from sour milk, lactic acid has been produced commercially since the 1880s in the United States and later in Europe. Worldwide, lactic acid production was approximately 250,000 metric tons per year in 2012 and is expected to reach 330,000 metric tons by the year 2015, with an average price of 1.25 US$ per kilogram in 2013 (food grade, 80–85 % purity).
Approximately 85 % of the demand for LA is from the food industry. The primary use of lactic acid is as a pH-adjusting agent in the beverage sector and as a preservative in the food industry. It is included in the Generally Recognized as Safe (GRAS) by the U.S. Food and Drug Administration [158] as a food ingredient and was deemed safe by the European Food Safety Authority as well [159]. The acceptable daily intake for LA was defined by the Joint FAO/WHO Expert Committee on Food Additives as ‘‘not limited,’’ and it is also supported by the Scientific Committee of Food.
In recent decades, the consumption of lactic acid due to its novel applications has grown quite rapidly, by 19 % per year. Nonfood use of lactic acid for polymer production contributes to this growth. Biodegradable polylactic acid is considered to be an environmentally friendly alternative to other plastics from petroleum. It is used in various fields, including drug delivery systems, medical devices, fibers, and packaging materials.
Lactic acid can be produced via chemical synthesis or carbohydrate fermentation. The chemical route has various issues, including toxic raw materials, low conversion rates, and especially the inability to produce the optically pure isomer. Therefore, approximately 90 % of lactic acid worldwide is produced by biotechnological processes, namely fermentations using renewable resources, which is relatively fast, economical, and able to supply selectively one or two stereoisomers of lactic acid.

Application of Lactic acid

lactic acid (sodium lactate) is a multi-purpose ingredient used as a preservative, exfoliant, moisturizer, and to provide acidity to a formulation. In the body, lactic acid is found in the blood and muscle tissue as a product of the metabolism of glucose and glycogen. It is also a component of the skin’s natural moisturizing factor. Lactic acid has better water intake than glycerin. Studies indicate an ability to increase the water-retention capacity of the stratum corneum. They also show that the pliability of the stratum corneum layer is closely related to the absorption of lactic acid; that is, the greater the amount of absorbed lactic acid, the more pliable the stratum corneum layer. Researchers report that continuous use of preparations formulated with lactic acid in concentrations ranging between 5 and 12 percent provided a mild to moderate improvement in fine wrinkling and promote softer, smoother skin. Its exfoliating properties can help in the process of removing excess pigment from the surface of the skin, as well as improving skin texture and feel. Lactic acid is an alpha hydroxy acid occurring in sour milk and other lesser-known sources, such as beer, pickles, and foods made through a process of bacterial fermentation. It is caustic when applied to the skin in highly concentrated solutions.

Lactic Acid is an acidulant that is a natural organic acid present in milk, meat, and beer, but is normally associated with milk. it is a syrupy liquid available as 50 and 88% aqueous solutions, and is mis- cible in water and alcohol. it is heat stable, nonvolatile, and has a smooth, milk acid taste. it functions as a flavor agent, preservative, and acidity adjuster in foods. it is used in spanish olives to prevent spoilage and provide flavor, in dry egg powder to improve disper- sion and whipping properties, in cheese spreads, and in salad dress- ing mixes.

 Fact Factory and Equipment Show