Malic acid (Formula NOOSSN2SN (OH) COOH) oksiyantarnaya, dibasic hydroxycarboxylic (fruit acid).It is represented by a colorless crystalline substance.Malic acid is well soluble in ethanol and water, poorly - in ether.
substance has a cleansing, anti-oxidant, anti-inflammatory, moisturizing and mild astringent properties.
Classification NOOSSN2SN acids (OH) COOH
Under natural conditions, common L-malic acid.Melting point - one hundred degrees.It is readily soluble in water.The solubility of ethanol 68.3 g diethyl ether - 1.9 grams per hundred grams of solvent.
D-malic acid, has a melting point of 130.8 degrees.Solubility in ethanol - 35.9 g in diethyl ether - 0.6 grams per hundred grams of solvent.
Both compounds insoluble in benzene.
Malic acid is endowed with the chemical properties of hydroxy acids.Its salts and esters referred to Malatya.When heated to one hundred degrees converts malic acid anhydride, an identical lactide.Over prolonged heating (up to 140-150 degrees) facilitates the elimination of water.As a result, the conversion of malic acid to fumaric acid, and rapid heating up to one hundred eighty degrees has formed and maleic anhydride.
NOOSSN2SN (OH) COOH is considered one of the most important intermediate components of metabolic processes in living organisms.Malic acid is involved in the metabolism in the form of malate.It is produced in the cycle of tricarboxylic acids, in gluconeogenesis.Malate after enzymatic reactions can be converted into pyruvate, fumarate oxaloacetate.
Get NOOSSN2SN (OH) COOH by reduction of tartaric acid, hydrolysis of D, L- bromyantarnoy acid.
In industry NOOSSN2SN (OH) COOH used in the manufacture of confectionery and fruit with water.Malic acid is used in winemaking.Suitable substance as a pH regulator and flavor.
Get malic acid (D, L) in the reduction of acid oksaliluksusnoy NOOSSOSN2SOON amalgam Na or its hydrolysis (oksaliluksusnoy acid) esters recovered.
naturally occurring substance found in the fruit acid.These include in particular the immature apples, mountain ash fruits, gooseberries, rhubarb.In tobacco malic acid is contained in the form of calcium salt.The small amount of it can be found in the wine.In nature NOOSSN2SN (OH) COOH is formed due to incomplete oxidation process sugars.Especially in a large amount of malic acid can be detected in immature grapes (from thirteen to fifteen grams per dm3).During ripening berries number NOOSSN2SN (OH) COOH is reduced to two to five grams per dm3.Such a decrease in the concentration due to the fact that the substance has been actively involved in the respiratory process.It should be noted that in the grapes from the northern regions to discover more malic acid than in the fruit from the southern regions.Contents NOOSSN2SN (OH) COOH, also depends on the weather conditions during the year and the variety of grape.
When alcoholic fermentation of the order of twenty-five percent malic acid absorb yeast.During the formation of the alcohol and carbon dioxide evolves.Bacterial fermentation results in the formation of high purity succinic acid.Condensation NOOSSN2SN (OH) COOH and urea synthesis is the basis of uracil (RNA component).
Under the influence of lactic acid bacteria can degrade malic acid to lactic acid.NOOSSN2SN (OH) COOH affects the flavor of the wine.The high content of malic acid is "green acidity" - a sharp taste.In these cases, it is biological "acidity".The principle of the process is based on the ability of yeast and lactic acid bacteria to absorb NOOSSN2SN (OH) COOH.