Dr. Robert Hutchison makes this statement regarding homemade jam: "The acids of the fruit, aided by the high temperature employed in the course of preparation, bring about the conversion of a considerable proportion of the cane-sugar into the invert form. Homemade jam is boiled for a longer time than the commercial article and con sequently contains more invert and less cane-sugar than the latter. The larger the proportion of cane sugar which has been inverted, the less likely is the jam to interfere with digestion." In a discussion of preserves and preserving, a number of preparations may be considered. It is but a step beyond the making of ordinary pre serves to the preparation of candied, glace or crystallized fruits. Preserves also naturally merge into fruit butters, jams, jellies and marmalades, some fruits being better adapted to one form than to another. These terms are often used inter changeably and vary in their application according to locality These several preparations will here be considered in order.
Preserves.
This type of sweet should not be served as freely as the ordinary canned fruits in which there is less sugar and more water, but there is no objec tion to its use in moderation. The fruit is cooked in thick syrup, and more thoroughly than for can ning. The denser the syrup the better the fruit will keep its shape, but when there is a tendency to jelly or caramelize, more water must be added. The proportion of sugar and water for the syrup must vary according to the juiciness of the fruit. For preserves, three-fourths to one pound of sugar is allowed for each pound of fruit. At the begin ing the syrup may consist of twice as much sugar as water, for average fruits. A few pieces are put into the kettle at once, that each may be sur rounded by the thick, hot syrup. As soon as these sections of fruit are cooked, in many cases becom mg somewhat transparent, they are removed to the jars, and more are put into the syrup. More water or sugar is added as needed. At the end, the remaining syrup is used to fill the jars containing the fruit, and often forms a firm clear jelly in which the fruit is imbedded.
Strawberries, stoned cherries, and any fruit likely to lose form and flavor if cooked, are sometimes sprinkled with sugar and the syrup thus formed is scalded and poured hot over the uncooked fruit placed in the jars. If the syrup is then scalded two or three days in succession and poured over the fruit again, there is little danger of fermentation.
Preserves will keep in jars that are not air-tight, but they should have much the same protection as jellies. The texture of each lot of fruit should be carefully observed, since varieties of the same fruit, and any one variety at different stages of growth, may produce a marked difference in the product. Hard fruits, as quinces, some pears and apples, may be improved by steaming until tender before cooking in the syrup. When any fruit is to
be preserved whole, the center must be as thor oughly sterilized as the outside, which must be accomplished by slow, gentle cooking, otherwise the surface will be broken and unsightly. There is a certain transparent appearance when the syrup has penetrated throughout.
Candied fruit.
This is to be classed with candies rather than with fruits, since the sugar predominates. Among the fruits most commonly subjected to this treat ment are apricots, cherries, peaches and pineap ples. The fruit is preserved in a thick syrup, then drained, cooled, dried and rolled in sugar. The time given to each process depends on the texture of the fruit and the size of the pieces. Experi ments in this country have been hurried too much to produce as satisfactory results as are obtained in France. One of our consuls has given this report on the methods pursued there : "Some of the denser fruits, as citron, are soaked first in sea water. All are carefully sorted as to size and degree of ripeness, and stones and parings are removed. The fruit is then plunged into boiling water and drained, thus removing much of the juice. If this process is too long continued the fruit is overcooked or left too woody, but if the juices are not extracted sufficiently, less sugar is absorbed and there is more danger of fermentation later. Experience is the only guide." Syrups of different densities must be provided for different fruits,—the softer the fruit the denser the syrup required. The fruit, after thorough draining, is soaked in the syrup for a time before heating. When a cloudy appearance in the trans parent syrup indicates the beginning of fermenta tion, the vessel containing syrup and fruit is heated to 212° Fahr. The process of soaking in syrup takes about six weeks, and the mass is heated about three times during the period. After this, the fruit may be crystallized by cooling slowly to about 90° Fahr., which causes the thick syrup that covers it to granulate. Or it may be glazed by dipping in a thick syrup and drying rapidly in the open air. The syrup remaining is worked up into various confections. Housekeepers frequently use up their orange and lemon skins in this way, and keep them in salt water until enough accumulate to make it worth while to prepare them. The salted skins are first boiled in fresh water to remove the salt and make them tender, then they are cooked in the syrup. Sweet flag and ginger roots should be cooked in several waters, to remove the too in tense flavor before they are candied. The yellow plum tomatoes make a fair substitute for figs, if treated in this way. In all cases care must be taken not to cook the fruit at too high tempera ture or to dry it too much.