Modern Gastronomy: A to Z
Additional information:
It is present in plants, especially the sugar beet.
Raffinose is also found in peas and beans. As it is a sugar that is more complex than the disaccharides, it does not break down easily and enters the small intestine without having been absorbed. It is assimilated (fermented) by the intestinal flora in the large intestine, and these microorganisms liberate gases that can cause flatulence.
Rancidity organoleptic perceptions What is it? An organoleptic nuance caused by the chemical alteration of fats. Additional information:
The triglyceride molecule is formed by glycerin, which is linked to three fatty acids. When triglycerides decompose, the fatty acid is freed and remains in the oil or the fat, creating a rancid taste. This phenomenon is nearly always caused by enzymes through a hydrolysis reaction (when oxygen initiates, it is called oxidation).
Wine that has been aged in casks and has acquired undesirable smells and flavors is also called rancid.
Rancidity development physical or chemical processes What is it? A phenomenon that often occurs when enzymes cause fat molecules to decompose through hydrolysis. The fatty acids that are oxidized are liberated and produce an off flavor, causing the perception of rancidity. Additional information:
It has nothing to do with the peroxidation of fats (formation of products that cause oxidations) although both phenomena are often linked. Antioxidant additives prevent peroxidation but no additives can prevent the development of rancidity; for example, rancidity development in butter, walnuts, ham, etc.
Unsaturated fatty acids (olive oil, etc.) are oxidized more easily than saturated fats and therefore are more prone to rancidity. Products (aldehydes and ketones) that are formed in rancidity reactions cause the unpleasant smell and flavor. 190
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