12 BULLETIN 656, U. S. DEPARTMENT OF AGRICULTURE. 



of solids. The dried pomace contains about 20 per cent sugar and 

 about 4 per cent of acid as tartaric. The pomace remaining in the 

 clot lis is removed by shaking the cloths. In order to insure the life 

 of the cloths, it is advisable to wash them each time they are used. 

 In some factories where screw presses are employed the cloths are 

 not washed of 1 ener t ban every fourth time of using. After the cloths 

 have been washed they are centrifuged or passed through a wringer 

 to remove the excess of moisture, and are ready for use again. In one 

 factory the washed cloths are dried by blowing hot air through them. 



STERILIZING THE JUICE AND BOTTLING IT FOR STORAGE. 



After having been strained through several thicknesses of burlap 

 to remove coarse particles, the juice flowing from the presses is united 

 in the sterilizers. The sterilizers are aluminum vats, or kettles, and 

 are steam-jacketed. In these the juice is heated to destroy the 

 living organisms, so that it may keep during the precipitation 

 period. If the juice, just as it runs from the presses, were filled 

 into the precipitation vessels, it would ferment in a very short time. 



The temperature to which the juice is subjected in the sterilizing 

 process is of the utmost importance to the flavor and aroma. The 

 effect of operations carefully conducted during the earlier stages 

 of the manufacturing process may be completely destroyed by care- 

 lessness during sterilization. This pertains not only to the tem- 

 perature employed during sterilization, but also to the manner in 

 which the kettles are filled. As in the process of heating the pulp, 

 care must be taken not to run the juice into a hot kettle, because 

 this would scorch the juice and give it a cooked taste. All kettles 

 should be filled at a low temperature and then heated. This rule 

 applies to every process in which the juice is heated. The sterilizing 

 temperature varies in the different factories, ranging from 176° 

 to 190° F. It is, of course, evident that the lowest possible tempera- 

 ture affording thorough sterilization is the best. It is inadvisable, 

 however, to go much lower than 1S0° F. on account of the danger 

 of fermentation. 



The precipitating vessels, glass carboys, or jugs of 5-gallon capacity 

 are now filled to within a few inches from the top with the hot sterile juice. 

 These have previously been heated in steam boxes for the purpose 

 of sterilizing them and of allowing them to accommodate themselves 

 gradually to the temperature of the juice they are to receive, this 

 latter precaution being necessary to avoid breakage. As soon as 

 the juice has been poured in, the vessels are closed with corks of 

 good quality, prepared by dipping into heated paraffin to close up 

 any pores or canals. The paraffining of the corks is a very important 

 measure, as the contraction of the cooling juice would draw air 

 through any space which might be left, causing mold or even fer- 



