260 STATE HORTICULTURAL SOCIETY. 



1. Boiling the fruit, usually with addition of some sugar, and sealing up 

 while hot, for exclusion of air, in vessels of glass or tin. "Canned fruits." 

 No way of excluding the air and keeping the fruit, without boiling, has been 

 found successful. Indeed, such brief boiling as might serve only to exclude 

 the air proves insufficient, and the fruit constituents have to be cooked, that 

 is, modified by exposure to heat, in order to insure their preservation. There- 

 fore this method results in the preservation of food prepared by cooking fruit, 

 rather than in the preservation of fruit itself. 



2. Drying, in the air or in partial vacuum, at ordinary or moderately ele- 

 vated temperatures. As the injury to the fruit is in proportion to the exposure 

 to air, and to the elevation of temperature, the best results will be attained by 

 dryness of the air, by rapidity ol the air current, and by diminished air pres- 

 sure. A brief exposure to warm air causes less injury than a long exposure to 

 cool air, but the temperature must be kept below the cooking point in all 

 cases. It would be one way to apply a rapid current of dry air at about 130°F; 

 and another way to maintain a partial vacuum at the same temperature. Air 

 may be dried by drawing through ice-cold passages until it deposits its mois- 

 ture, or by passing over quick-lime, chloride of calcium, or other material 

 absorbing moisture. Quick-lime would be afterward used as slaked-lime; chlo- 

 ride of calcium would, dried in the furnace, do to use over again. 



3. Saturation with sugar, in a syrupy liquid or in a moist solid. Fruits 

 already contain sugars, and the more richly saccharine they are, the more 

 easily are they preserved by drying. Some grapes contain so much sugar that 

 that they are preserved almost un wilted by the imperceptible concentration of 

 their juices effected in ordinary keeping in the air. By a little further drying 

 they become raisins. When dilute, a solution of sugar is not a preservative, 

 but a subject of fermentation. There should be from one and a half to two 

 parts of sugar to one part of water, to secure preservation. Grape sugar, or 

 glucose, is not so good a preservative as cane sugar. In cunning fruits, as 

 above given under method 1, the preservative power of sugar is generally a 

 partial reliance. When to be kept in the air, the sugar is applied as a preserva- 

 tive, either along with cooking, as in the jams, iellies, and old time syrupy 

 ''preserves," or along with partial drying, corresponding to that of figs, raisins, 

 and fruits "dried in sugar." 



4. The use of antiseptics. These agents have never been generally employed 

 for the preservation of fruits. Meats are salted for extensive use, but the use 

 of preservatives other than sugar, for the keeping of fruits, has not gone 

 beyond the stage of experiment. A few substances have been tried as such 

 preservatives. Some years ago the writer saw a jar of pears, uncooked, 

 immersed in a solution of sulphurous acid. The jar had been stoppered but 

 not sealed, and the fruit, which was pared, was really quite fresii, having been 

 so kept for several months. The liquid smelled strongly of burning sulphur, 

 and tasted astringent and somewhat acidulous, and contained sulphuric acid. 

 The astringent taste was perceptible in the fruit as well. Very lately a member 

 of this society presented to the writer for analysis a sample of an article 

 absurdly entitled "ozone," consisting essentially of sulphur to be burned and 

 so ajti^licd as sulphurous acid in vapor.* Sulphurous acid is the opposite of 



* "A box containing one pounrt of a blaclc powilcr, lastclcss, insoluble in ■water, of a slight arc 

 matic odor, and solil for two dollars, by the I'rentis Preserving Co., limited, southeast corner 

 Ninth and Uacc streets. Cincinnati, Ohio. The label states that this preservative is not any of the 

 old exploded processes, but is sinijily anil purely ' Ozone;' also that there is nothing on the face of 

 the earth which ozone, the new preservative, will not preserve for all time in a perfectly fresh 

 and palatable condition. The directions state that the powder is to be ignited and allowed to 



