This section is from the book "Facts Worth Knowing", by Robert Kemp Philip. Also available from Amazon: Inquire Within for Anything You Want to Know.
The grand secret of preserving is to deprive the fruit of its water of vegetation in the shortest time possible; for which purpose the fruit ought to be gathered just at the point of proper maturity. An ingenious French writer considers fruit of all kinds as having four distinct periods of maturity - the maturity of vegetation, the honeyfiea-tion, of expectation, and of coction
642. The first of these he considers as the period when, having gone through the vegetable processes up to the ripening, it appears ready to drop spontaneous!v. This however is a period which arrives sooner in the warm climate ot France than in the colder orchards of America; but its absolute presence may be ascertained by the general filling out of the rind, by the bloom, by the smell, and by the facility with which it may be plucked from the branch. But even in France, as generally practised in America, this period may be hasteued, either by cutting circularly through the outer rind at the foot of the branch, so as to prevent the return of the sap, or by bending the branch to a horizontal position on an espalier, which answers the same purpose.
643. The second period, or that of honeyfication, consists in the ripeness and flavour which fruits of all kinds acquire if plucked a few days before arriving at their first maturity, and preserved under a proper degree of temperature. Apples may acquire or arrive at this second degree of maturity upon the tree, but it too often happens that the flavour of the fruit is thus lost, for fruit over ripe is always found to have parted with a portion of its flavour.
644. The third stage, or of expectation, as the theorist quaintly terms it, is that which is acquired by pulpy fruits, which, though sufficiently ripe to drop off the tree are even then hard and sour. This is the case with several kinds both of apples and pears, not to mention other fruits, which always improve after keeping in the confectionery, - but with respect to the medlar and the quince this maturity of expectation is absolutely necessary.
645. The fourth degree of maturity, or of coction, is completely artificial, and is nothing more nor less than change produced upon fruit by the aid of culinary heat.
646. We have already pointed out the first object necessary in the preservation of fruit, its maturity or vegetation; and we may apply the same prin ciple to flowers or leaves which may bo gathered for use.
647 The Flowers ought to be gathered a day or two before the petals are ready to drop off spontaneously on the setting of the fruit; and the leaves must be plucked before the season has begun to rob them of their vegetable juices. The degree of heat necessary for the purpose of drying must next be considered, as it differs considerably with respect to different substances.
648. Flowers or Aromatic Plants require the smallest increase of heat beyond the temperature of the season, provided that season be genial; something more for rinds or roots, and a greater heat for fruits; but this heat must not be carried to excess.
649. Philosophic Confectioners may avail themselves of the thermometer: but practice forms the best guide in this case, and therefore we shall say, without speaking of degrees of Fahrenheit or Reaumur, that if the necessary heat for flowers is one and a quarter, that for fruits one and three quarters, or nearly double of what one may be above the freezing point.
 
Continue to: