36 MASS. EXPERIMENT STATION BULLETIN 315 



Stabilizers for High Fat Ice Cream. (W. S. Mueller.) Only a small amount of 

 time has been given to this study during the past year. Some new or improved 

 stabilizers appearing on the market are being tried out. 



A Study of Ice Cream High in Fat Content. (M. J. Mack.) Work on compara- 

 tively rich ice creams, which are being sold in increasingly larger amounts, was 

 continued throughout 1934. Previous studies revealed that when ice cream mixes 

 of high fat content (18 and 20 percent fat) are made under usual processing condi- 

 tions they are excessively viscous and produce crumbly ice cream with an un- 

 desirable melting appearance. The use of butter, frozen cream, or plastic cream 

 in place of all or a part of the sweet cream needed to supply the butter fat markedly 

 increases these three defects. 



The use of three successive stages of homogenization entirely eliminates the 

 problem of excessive viscosity and decreases the other defects already named. 

 Pressures of 2,000, 500, and 150 pounds are suggested as satisfactory maximum 

 pressures for the first, second, and third valves, respectively, when homogenizing 

 an 18 percent butter fat mix. With a 20 percent fat content, somewhat lower 

 pressures of 1500, 500, and 150 pounds are suggested as maximum pressures. 



A crumbly body may be prevented in high butter fat ice creams by increasing 

 the sugar content to 16 to 17 percent, depending somewhat on the fat content 

 of the mix. If the use of cane sugar alone produces an excessively sweet taste, the 

 substitution of corn sugar for 3 or 4 percent of the cane sugar is recommended. 



Increasing the sugar content to 16 to 17 percent improves the melting appear- 

 ance and reduces the melting resistance of high fat ice creams. 



The use of three different stages of homogenization entirely eliminates ex- 

 cessively high viscosity which invariably occurs in chocolate ice cream mixes 

 of high solids content. 



The Utilization of Frozen Fruits in Ice Cream. (M. J. Mack and C. R. Fellers, 

 Department of Horticultural Manufactures.) This project was revived after a 

 lapse of two years to study more thoroughly the practice of slicing strawberries 

 before freezing for later use in ice cream. About 500 pounds of whole and sliced 

 frozen strawberries were furnished by the R. D. Bodle Company and Dr. H. C. 

 Diehl of the United States Frozen Pack Laboratory, both of Seattle, Wash- 

 ington. 



The frozen whole and sliced strawberries were thawed, examined, and used in 

 ice cream. The practice of slicing the berries before freezing seems desirable. 

 The packs consisting of sliced fruit contained less undissolved sugar than whole- 

 fruit packs, showed less surface discoloration, contained firmer pieces of fruit 

 of better flavor and color, and appeared to contain less syrup. To the fruit packer, 

 slicing strawberries before freezing seems to be another means of improving his 

 product. 



Frozen sliced strawberries impart more flavor to strawberry ice cream than do 

 frozen whole berries of the same run. However, the difference is not marked. 

 Such factors as variety and degree of ripeness of the fruit and the sugar content 

 of the pack were found to affect the flavor of strawberry ice cream to a greater 

 extent than slicing the fruit before freezing. 



Ice Cream Frozen Without Stirring. (M. J. Mack.) A large number of bulletins, 

 pamphlets, and recipe books have been published which contain directions for 

 freezing ice cream without agitation. These recipes are primarily designed for 

 use with the electric refrigerator. Several commercial preparations are now on the 



