Fruit softening, effect

The ability of metal ions to modify the texture of fruit and vegetable tissue has been studied since 1939, when Kertesz (l) found that calcium ions improved the firmness of tomatoes. A very simplified generalization of the effects of metal ions on fruit and vegetable texture is that monovalent cations, usually Na+ and K, cause tissue softening. Examples of this softening effect include results with peas (2.31, dried peas (4), carrots (5), potatoes (6) and green beans (7). On the other hand calcium, a divalent cation,... 

The production of ethylene in fruit tissue and in small amounts in leaves may justify its consideration as a hormone, functioning in the gaseous state, Cherimoyas and some varieties of pear produce 1000 times the effective physiological concentration. Ethylene formation is closely linked to oxidation and may be centered in the mitochondria. Its effects are to promote cell-wall softening, starch hydrolysis, and organic add disappearance in fruits—the syndrome known as ripening. Ethylene also decreases the geotiopic responses of stems and petioles. 

Irradiation has a serious effect on softening and texture changes of many fruits. The level required for disease control in grapes is too high to avoid extreme softening of the tissues. Therefore, irradiation does not appear possible for grapes. 

Traditional use Thin branches, bark and fruits are used in folk medicine. Fruits are used as a laxative to treat chronic constipation, and the treatment starts to take effect 8-10 h after ingestion. A decoction of the fruits, with the addition of dairy whey, oil, and baking soda is used as a laxative for atonic and spastic constipation, and is used as a stool softener for cases of hemorrhoids and wounds to the colon. An infusion of the fruits in vodka is used externally to treat rheumatism. A decoction of the branches is used internally to treat ulcers and externally, as a compress to heal wounds. A decoction of the bark is used to treat stomach catarrh, low acidity of the stomach, and Polish plait (Maznev 2004). 

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