Sugar acetates, bitterness

Acetic acid is a weak carboxylic acid with a pungent odor that exists as a liquid at room temperature. It was probably the first acid to be produced in large quantities. The name acetic comes from acetum, which is the Latin word for sour and relates to the fact that acetic acid is responsible for the bitter taste of fermented juices. Acetic acid is produced naturally and synthetically in large quantities for industrial purposes. It forms when ubiquitous bacteria of the genera Acetobacter and Clostridium convert alcohols and sugars to acetic acid. Acetobacter, especially Acetobacter aceti, are more efficient acetic acid bacteria and produce much higher concentrations of acetic acid compared to Clostridium. 

Dry vermouths usually have a higher alcohol content, lower sugar content, and are lighter color than sweet vermouths. In addition, they are usually more bitter in flavor. In a typical French dry vermouth, the alcohol content is 18% by volume, reducing sugar 4%, total acidity (as tartaric acid) 0.65%, and volatile acidity (as acetic acid) 0.053% (Joslyn and Amerine, 1964). 

A first requirement for a substance to produce a taste is that it be water soluble. The relationship between the chemical structure of a compound and its taste is more easily established than that between structure and smell. In general, all acid substances are sour. Sodium chloride and other salts are salty, but as constituent atoms get bigger, a bitter taste develops. Potassium bromide is both salty and bitter, and potassium iodide is predominantly bitter. Sweetness is a property of sugars and related compounds but also of lead acetate, beryllium salts, and many other substances such as the artificial sweeteners saccharin and cyclamate. Bitterness is exhibited by alkaloids such as quinine, picric acid, and heavy metal salts. 

Phytochemistry Leaves contain alkaloids, glycosides, bitter substances, sesquiterpene lactones (arctiopicrin and onopor-dopicrin), vitamin C and K, resins, titratable acids, sugars, tannins, terpenoids (taraxasteryl acetate), etc. Seeds contain alkaloids, acetates of lupeol and amyrin, and drying fatty oil (Khalmatov et al. 1984 Ul chenko et al. 1993 Khalilova etal.2004). 

Some nutrients, such as proteins, peptides and amino acids, Hpids, carbohydrates, vitamins and minerals, are also sensoriaUy active substances (e.g., sweet or bitter). The main nutrients along with other substances (certain organic acids, such as acetic and citric acids, and sugar alcohols, such as glucitol, known as sorbitol) can simultaneously also be a source of energy, for example, ethanol has a relatively high energy value. 

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