Caprinic acid, oxidation

CAPRINIC ACID (334-48-5) Combustible solid (flash point >230°F/>110°C cc). Incompatible with sulfuric acid, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, vinyl acetate. May increase the explosive sensitivity of nitromethane. Attacks most common metals. 

CAPRINIC ALCOHOL (112-30-1) Combustible liquid (flash point 180°F/82°C oc). Reacts, possibly violently, with oxidizers, acetaldehyde, alkalineearth, alkali metals, strong acids, ammonium persulfate, strong caustics, aliphatic amines, benzoyl peroxide, boranes, bromine dioxide, chromic acid, chromium trioxide, dialkylzincs, dichlorine oxide, ethylene oxide, hypochlorous acid, isocyanates, isopropyl chlorocarbonate, lithium tetrahydroaluminate, nitric acid, nitrogen dioxide, pentafluoroguanidine, perchlorates, peroxides, permanganates, phosphorus pentasulfide, sulfuric acid, tangerine oil, triethylaluminum, triisobutylaluminum. 

Lipases in stored butter gradually release fatty acids from tri-acylglycerols, and their presence can be detected as a rancid and soapy flavour when they reach 30-40% of their threshold concentrations, which is a result of their synergism. The reaction is called hydrolytic rancidity. Responsibe for the rancid flavour is mainly butyric acid, followed by caproic acid. Caprylic acid has a rancid soap-like flavour, capric and lauric acids only have soapy flavours. Odour (and taste) threshold concentrations in butter made from sweet cream are 50 (60) mg/kg for butyric acid, 85 (105) mg/kg for caproic acid, 200 (120) mg/kg for caprylic acid, >400 (90) mg/kgfor caprinic (capric) acid and >400 (130) mg/kg for lauric acid, respectively. In long term stored butter, active oxidative rancidity products are (E)-non-2-enal, (Z)-non-2-enal in particular, while less active products are (Z)-hept-4-enal, oct-l-en-3-one and others. The rancid and soapy odour in butter can also be caused by contamination with anion active detergents, such as natriumdodecyl sulfate. 

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