80 EXPERIMENT STATION EECOED. 



Care of cream on the farm and ice house construction, C. W. Fryhofeb 

 (Bui. Vt. Dept. Agr., No. 20 (1914), pp. 31, figs. 9).— The subjects discussed in 

 this bulletin are the relation of the quality of butter to the quality of cream, the 

 importance of cleanliness, temperature, thickness of cream, frequency of deliv- 

 ery at the creamery, methods for cooling cream on the farm, specifications for 

 making the cream-cooling box, ice storage, ice houses, variations in the patron's 

 cream test, relations between the patron and creamery, and overrun. 



Two factors causing variation in the weig-ht of print butter, H. M. PiCK- 

 EEiLL and E. S. Guthrie {New York Cornell 8ta. Bui. 355 {1915), pp. 99-111, 

 figs. S). — ^As the result of their studies of the causes of variation in the weight 

 of print butter the authors found that " the variation of pore space, which 

 ranges from 0.5 to over 6 per cent in freshly m;ide butter, is important in the 

 printing process. Print butter gradually loses weight in storage. The rate of 

 loss depends principally on the temperature and humidity of the storage room. 

 If the temperature is kept down to 50° F. and the humidity is kept above 90 per 

 cent, at least a month, and perhaps much longer, will be required for the shrink- 

 age to approximate the limit set by law, provided the prints are packed in boxes. 

 If the temperature is 60° or above and the humidity is 85 per cent or below, the 

 shrinkage will approximate the limit set by law in a space of 10 days to 2 

 weeks, even if the prints are packed in boxes. 



" The degree of shrinkage is not inversely proportional to the weight of the 

 wrapper used, as is generally supposed. The degree of shrinkage decreases to a 

 considerable extent when the prints are placed in cartons. The other two meth- 

 ods of packing, however, leaving the prints dry after placing them in boxes or 

 sprinkling them with water, produce about the same effect on the degree of 

 shrinkage. In the average small-store refrigerator the loss will approximate the 

 limit set by law in a space of 10 days when the prints are piled loosely on 

 shelves." 



Mechanism of overrun in the manufacture of ice cream, M. Mortensen 

 (Cream, and Milk Plant Mo., 3 (1915), No. S, pp. 21, 22).— The author discusses 

 the factors determining the amount of overrun in the manufacture of ice cream, 

 among them the viscosity and temperature of the cream used, the temperature 

 of the ice cream when drawn from freezer, the fillers used, and the temperature 

 of the brine. 



It is stated that pasteurization reduces the viscosity of milk and cream, and 

 pasteurized cream, if used soon after pasteurization, will not retain as much air 

 and the yield is accordingly reduced. The body of the ice cream is also 

 coarser. Pasteurized cream, due to its lower viscosity, affords less resistance to 

 churning, and hence during the freezing process butter particles are formed, 

 which, in turn, reduce the viscosity of the mix and the yield. By holding the 

 cream at within a few degrees of freezing temperature for not less than 24 

 hours after pasteurizing, the viscosity is increased and the formation of butter 

 particles is less prominent. 



A cream produced from milk containing small fat globules is deemed most 

 satisfactory for ice-cream making, hence the value of stripi>ers' milk and of 

 cream from milk produced by the Holstein breed. Homogenization increases 

 viscosity, and such cream is frozen without the formation of butter granules 

 and therefore a greater yield and a smoother ice cream is obtained. 



It is said that the principal advantages obtained from fillers are the increase 

 In viscosity of the mix, the prevention of formation of butter particles during 

 the freezing process, and the fact that they add strength to the cream films 

 surrounding the moisture i)articlos, thus insuring a body possessing better keep- 

 ing properties. It is thought that fillers do not increase the yield obtained, but 



