Peaches tannin

So far as is known, the catechins are never glycosylated, and the leuco-anthocyanins seem also to occur, as a rule, uncombined with sugars. Johnson et al. (1951) report, however, that the main component of peach tannin (which from the description they give resembles in every respect a leuco-anthocyanin) is associated with carbohydrate, since glucose appears on hydrolysis with HCl. 

Johnson, G., Mayer, M. M., and Johnson, D. K. 1951. Isolation and characterization of peach tannins. Food Research 16, 169. 

Primus persica (L.) Batsch. Tou Ren (Peach) (leaf, flower, fruit) Malic acid, citric acid, octalactone, leucoanthocyanins, tannins, hexalactone, hectalactone, benzyl alcohol, nonalactone, decalactone, ethanol, hexanol, acetadehyde, benzaldehyde, acetic acid, pentanoic acid, hexanoic acid.50 Astringent, febrifuge, parasiticide, diuretic, sedative, vermifuge. 

Glycerite of tannin Oak extract Peach juice Peaches, dried Plum juice Plums, dried Prune juice... 

Tannins Catechin polymers Epicatechin polymers Ellagitannins Proanthocyanidi ns Tannic acids Grape seed/skin, apple juice, strawberries, raspberries, pomegranate, walnuts, peach, blackberry, and plum 118]... 

Guadagni DG, Nimmo CC (1953) Effect of growing area on tannin and its relation to astringency in frozen Elberta peaches. Food Technol 7 59-61... 

Reeve RM (1959) Histological and histochemical changes in developing and ripening peaches. I. The catechol tannins. Am J Bot 46 210-217... 

Senter SD, Callahan A (1990) Variability in the quantities of condensed tannins and other major phenols in peach fruit during maturation. J Food Sci 55 1585-1587, 1602 Sistrunk Wa (1985) Peach quality assessment fresh and processed. In Pattee HE (ed) Evaluation of quality of fruits and vegetables. AVI Publishing, Westport, CT, pp 1-46 Swain T (1965) The tannins. In Bonner J, Varner J (eds) Plant biochemistry. Academic Press, New York, pp 552-580... 

Fruit is, with few exceptions, always very acidic and the maximum acid levels in fruits occur in the period before full maturity. The pH of fruit juices is generally lower than 4.0, but in over-ripe pears, cherries and peaches may increase up to pH 4.5 and in over-ripe elderberries may even reach a value of 4.7. The level of adds in the fruit depends on the type, and is usually 10-30 g/kg, a lower amount of adds (about 1 g/kg) is found in pears, while citrus fruits contain higher amounts of adds (about 80 g/kg). A sour taste is often modified by the presence of carbohydrates, tannins, ethanol or various cations and other substances. Carbohydrates weaken the sour taste of adds and tannins, and alcohol, on the contrary, emphasises their taste. 

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