Chemical Properties
The quince is a deciduous, thornless shrub or small tree, 4 to 6 m (13 to 20 ft) high and 3 to 4.5 m (10 to 15 ft) spread, with crowded branches and a low, crooked habit. Young branchlets are covered with a pale-grayish wool. It bears pink or white solitary flowers and has alternate, ovate leaves tapering at one end and fruits resembling a large, yellow apple. Each carpel bears many seeds covered by mucilage. The plant is native to central Asia. The parts used are the fruits and seeds. Quince has an agreeable,
slightly acid flavor. The hard, acid flesh of unripe fruits, harvested in October, is used in marmalades, jellies and preserves. The seeds
from the ripe fruits yield quince-seed mucilage, used as a thickening agent in place of tragacanth gum.
Occurrence
Quince is found in Southwest and Central Asia and in Europe.
Uses
Quince traditionally has been used to treat diarrhea, gonorrhea, dysentery, Candida infections of the mouth, and sore throat. It is also a component in lotions, creams, and mouthwash. Quince is used topically to treat canker sores and gum disease.
Composition
The β-D-gentiobioside [β-D-glucopyranosyl(16)-β-D-glucopyranoside] of 3-hydroxy-β-ionol has been isolated and characterized in quince (C. oblonga) fruit.* Amygdalin, which hydrolyzes in the presence of emulsion to yield hydrogen cyanide, benzaldehyde and glucose, has been reported among various other constituents (Burdock, 1997). The average nutritional composition of quince fruit (per 100 g) is water 83.8%, protein 0.4 g, fat 0.1 g, carbohydrate 15.3 g, calcium 11 mg, phosphorus 17 mg, potassium 197 mg, vitamin A 40 IU, vitamin B1 (thiamin) 0.02 mg, vitamin B2 (riboflavin) 0.03 mg, vitamin C 15 to 20 mg, iron 0.7 mg and sodium 4 mg.
