Principles of Fruit Preservation

The book deals with the scientific principles and control of the various processes involved in the manufacture of jams and fruit jellies, fruit caning and fruit drying. For an understanding of these it has been necessary to give some account of the composition of fruits, especially in regard to their contents of acids, sugars and pectin. The manufacture of jams and jellies, in particular, involves a delicate balance between these three classes of substances; hence pectin and pectin-sugar-acid gel are treated at length. The various methods of preserving fruits for jam-making and canning out of season are also described, and there is an account of the control of the actual manufacturing processes by the works chemist. In the section on fruit canning considerable space has been allotted to the problems of can-corrosion, a major source of trouble with certain products, especially in warm climates. The various stages of the canning process are also described and discussed in their proper sequence, and there are chapters on the standardization and examination of canned products and on fruit bottling. The section on fruit drying deals with recent researches both in connection with sun-drying and with artificial dehydration. Also given with subject of prune-drying and drying of grapes. There are also discussions of the problems connected with the storage and packing of dried fruits and of the general considerations in constructing and working a dehydrating plant.