a four carbon acid, ch3ch2ch2cooh, with an unpleasant odor that occurs in butter and animal fat as the glycerol ester. a four carbon acid, ch3ch2ch2cooh, with an unpleasant odor that occurs in butter and animal fat as the glycerol ester. Found in fresh and cooked apples, banana, sour cherry, papaya, strawberries, wheat bread, cheeses, butter and coffee. Flavouring agent
Butyric acid (from Greek ???????? = butter), also known under the systematic name butanoic acid, is a carboxylic acid with the structural formula CH3CH2CH2-COOH. Salts and esters of butyric acid are known as butyrates or butanoates. Butyric acid is found in rancid butter, parmesan cheese, vomit, and body odor and has an unpleasant smell and acrid taste, with a sweetish aftertaste (similar to ether). It can be detected by mammals with good scent detection abilities (such as dogs) at 10 ppb, whereas humans can detect it in concentrations above 10 ppm.; Butyric acid is a fatty acid occurring in the form of esters in animal fats and plant oils. The triglyceride of butyric acid makes up 3% to 4% of butter. When butter goes rancid, butyric acid is liberated from the glyceride by hydrolysis leading to the unpleasant odor. It is an important member of the fatty acid sub-group called short chain fatty acids. Butyric acid is a weak acid with a pKa of 4.82, similar to acetic acid which has pKa 4.76. The similar strength of these acids results from their common -CH2COOH terminal structure. Pure butyric acid is 10.9 molar.; Butyric acid, a four-carbon fatty acid, is formed in the human colon by bacterial fermentation of carbohydrates (including dietary fiber), and putatively suppresses colorectal cancer (CRC). Butyrate has diverse and apparently paradoxical effects on cellular proliferation, apoptosis and differentiation that may be either pro-neoplastic or anti-neoplastic, depending upon factors such as the level of exposure, availability of other metabolic substrate and the intracellular milieu. In humans, the relationship between luminal butyrate exposure and CRC has been examined only indirectly in case-control studies, by measuring fecal butyrate concentrations, although this may not accurately reflect effective butyrate exposure during carcinogenesis. Perhaps not surprisingly, results of these investigations have been mutually contradictory. The direct effect of butyrate on tumorigenesis has been assessed in a no. of in vivo animal models, which have also yielded conflicting results. In part, this may be explained by methodology: differences in the amount and route of butyrate administration, which are likely to significantly influence delivery of butyrate to the distal colon. (PMID: 16460475) Butyric acid is a carboxylic acid found in rancid butter, parmesan cheese, and vomit, and has an unpleasant odor and acrid taste, with a sweetish aftertaste (similar to ether). Butyric acid is a fatty acid occurring in the form of esters in animal fats and plant oils. Interestingly, low-molecular-weight esters of butyric acid, such as methyl butyrate, have mostly pleasant aromas or tastes. As a consequence, they find use as food and perfume additives. Butyrate is produced as end-product of a fermentation process solely performed by obligate anaerobic bacteria.; The acid is an oily colorless liquid that is easily soluble in water, ethanol, and ether, and can be separated from an aqueous phase by saturation with salts such as calcium chloride. Potassium dichromate and sulfuric acid oxidize it to carbon dioxide and acetic acid, while alkaline potassium permanganate oxidizes it to carbon dioxide. The calcium salt, Ca(C4H7O2)2·H2O, is less soluble in hot water than in cold.
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