794 EXPERIMENT STATION RECORD. 



TECHNOLOGY. 



Preservation of unfermented grape mtist, F. T, Bioletti and 

 A. ]S1. DAL PiAZ {Calif()i'iu(( Sfd. Ihil. UO. pp. 12,f(js. .^). — The com- 

 position of pure grape mu.st and of the products sonietinies found on 

 the market is discussed, as well as the causes of spoiling of grape juice 

 and the chemical and physical means of preventing fermentation. 

 Chemical methods, /. e.^ the use of germ poisons or antiseptics, are 

 condemned. The physical methods, especially those depending upon 

 the application of a temperature sufficiently high to kill all germs, are 

 considered safest and most relial)le. Such a method is described in 

 some detail. It is recommended that onl}" clean and perfectl}^ sound 

 grapes, picked and handled when cool, should be used. After the 

 juice is expressed it is allowed to settle :2tl: hours and then run through 

 a continuous pasteurizer in which it is heated to 80^ C. (176° F.), but 

 comes out not w^armer than 25° C. (77° F.). It is again allowed to 

 settle in closed sterilized casks and filtered. For this purpose a filter 

 so constructed that the must passes upward through the filtering 

 medium under pressure is recommended. The filtered juice is placed 

 in bottles previously sterilized, and the stoppered bottles are kept in 

 a water bath heated to 85° C. (185° F.) for 15 minutes (for quart 

 champagne bottles). B}^ this means the contents of the bottles are 

 heated to about 75° C. (167° F.). If a higher temperature is used 

 for the second sterilization than for the first the must becomes cloudy. 

 To prevent the growth of mold on the corks in storage the}^ may be 

 dipped in hot paraffin or 2 per cent bluestone solution. 



Utilization of pure yeasts in -wine fermentation, K. Chodat 

 {Arch. Sci. Phyy. d Sat., S {1800), pp. J,SW, oSO; ahs. In Jour- P"'/- 

 Mia^os. Soc. \London\ 1900, No. 2,p)p- ^^7, ^55).— The advantages of 

 the use of pure yeasts in wine fermentation are pointed out and details 

 of an investigation of a red wine of Crete are given. Six species of 

 Saccharomyces w^ere isolated from this wine, one of which belonged to 

 the S. apiritTafus group, the rest l^eing true yeasts. The amount of 

 alcohol produced b,v these different yeasts in sterile must is given, and 

 the quantity of glucose destroyed in the production of alcohol or in their 

 own maintenance varied from 7 to 81:. 1: per cent of the amount present. 



Keeping cider, Schellexbeko {Jaliresber. Yers. Stat, u Sch>de, 

 Wadensioeil, 1897-98., p)?- '5-:^--^6').— Three casks, each containing 600 

 liters, were filled with pear cider of like quality. After fermen- 

 tation the cider was left with the dregs in one case, drained off in the 

 .second, and filtered through a cellulose filter in the third, after which 

 the cider in all 3 casks was left in a storage cellar. The summer fol- 

 lowing the cider in the first cask tasted of the dregs and was of poor 

 (juality; that in the second Avas clear and tasted pure. The cider in 

 the third cask was the b(^st in qualit}' of all. It was not only clear 

 and pure tasting, but had also a fresh, lively character. The conclu- 



