The quality of fruits depends largely upon the proportion of sugar, gum and pectin to free acid, largely also upon the proportion of soluble to insoluble matters, but in very great measure also upon the aroma. This quality is due to the presence of characteristic ethers, often accompanied by essential oils, although not of course in ponderable percentage. Culti vation and selection operate strongly on all three factors.
Keeping of Fruit.— Many of the finest fruits undergo very speedy decomposition, which, as distinguished from the intrinsic proe esses of ripening, is due to the attacks of bacteria, molds or yeasts; so the problem of their preservation is therefore primarily one of preventing these. In damp and stagnant air, especially with considerable or frequent changes of temperature, these fungous pests multiply with special readiness; hence a fruit-room must be cool and shady, yet dry and airy, and the fruit carefully gathered rather before full ripeness, handled so as to avoid in any way bruising or tearing the skin, and laid out and occasionally looked over so that rottenness in one may not affect the rest. Under these con ditions apples especially may be kept for many months; indeed many varieties of fruit — for example, winter-pears require these condi tions for satisfactory ripening. On antiseptic
principles we see how it is that the dense skinned and wax-coated grape can be so largely imported in sawdust, or how unripe gooseber ries and even very perishable pears can be kept for months similarly packed in well-sealed jars in a cool place. The process of preserving with sugar in jars promptly covered up is similarly an antiseptic one; but in the systema tic application of antiseptic princples we may still look for considerable progress in the pres ervation and transport of fresh fruit upon a large scale. 'The method of drying fruit has also.been in use from remote times, especially with dates, figs and raisins. (See CIDER; Faun GROWING; FRUIT INDUSTRY; FRUITS, COLD STORAGE OF ; GARDEN; and articles on the various fruits, as APPLE, CHERRY, PEACH, etc.). Consult works on " fruit-culture by Bailey, Burbidge, Cheat Downing, Du Breuil, Fish Fuller, Hogg, Roe, Thomson, Wood, Paddoci and Whipple, Sears, Barry, Warder, Thomas, Beach, Hedrick, Kains, Hume, Colt, Waugh, Wilkinson, Husman, Budd and Hansen, Card, Wickson, Webb, White, Popenoe, Munson, Chorlton, Fletcher, Maynard, Green and Meech.