METHODS OF FRUIT PRESERVING. 



569 



name of Normandy Biffins, Californian Apple Rings, &c, but little 

 evaporation has as yet been practised in this country. 



A firm flesh, adaptability for the paring machine, a relatively high 

 proportion of dried product to the fresh fruit, a small percentage of 

 water whereby the duration of the drying and consequently the cost 

 are much reduced, a small core, and a good shape are the principal points 

 to notice in selecting Apples for drying. 



Great care should be taken to select Apples of the right degree 

 ripeness. Under-ripe and over-ripe fruits are equally unsuitable, but 

 with a little care the exact grade in each variety treated can be easily 

 observed. 



The Apples are cored, pared, and sometimes cut into rings, and are 

 also frequently sulphured so as to preserve their colour and prevent the 

 oxidation which in many varieties would otherwise occur. Opinions are 

 much divided as to whether this sulphuring is injurious to health or 

 otherwise, and it may perhaps be true that when the operation is carried 

 out in a specially constructed apparatus it is harmless, but is liable to 

 be otherwise when it is carried out at the same time as the drying. The 

 prepared Apples are kept in a vessel of perfectly clean water containing a 

 small quantity of salt until they are put in the dryer, which prevents 

 oxidation and discoloration. The thinner the rings are the quicker they 

 dry ; and the lighter their colour when dry the better they sell. 



The fruits are laid on the wire-bottomed trays of the dryer, placed 

 in the machine, and the temperature regulated to 180-210° F. Then if a 

 higher temperature, namely 240°, be used, with a strong current of air, the 

 prcduct is dryer, more nourishing, and keeps better, but the flavour is 

 quite changed. The time occupied varies from two to four hours, accord- 

 ing to the variety of the Apple, but from two to two and a half hours is 

 the usual time. Whole Apples usually require a much longer time — eight 

 to ten hours, according to the size and variety. 



After the evaporation of the water in which it was held suspended, the 

 whole of the " pectin " or fruit gluten remains unchanged in the cells, 

 and is visible in a condensed form on the outside of the fruit, and all 

 germs and ferments are destroyed by the heat. The waste matter (core, 

 &c.) in Apples varies from 25 to 33 per cent., and the finished product weighs 

 from about 11 to 14 per cent, of the fresh fruit. The proportion of water 

 removed from the fruit and the concentration and also formation of sugar 

 in well dried fruits are given by Dr. Konig, after careful analysis, as 

 follows : Fresh Apples contain on an average, besides other matter, 83-58 

 per cent, water and 7*73 per cent, sugar ; dried Apples yield, however, 

 27*95 per cent, water and 42*83 per cent, sugar. The relatively high 

 percentage of water found in the dried fruits is, however, due to the fact 

 that they re-absorb a certain quantity of water from the atmosphere when 

 they have been rendered very dry. 



Pears are dried much in the same way as Apples, but never in rings. 

 Having a higher percentage of water they take longer time ; and as they 

 also have a large proportion of sugar it would seriously injure the product 

 if they were dried too rapidly. 



For drying, Pears are best treated when half-ripe, as they thus dry 

 easiest and produce the largest quantity of the prepared product. Fully 



p 



