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MASS. EXPERIMENT STATION BULLETIN 268 



cream, after melting, tlie fat was no lonjier jiresent in its original jihysi- 

 cal form. After frozen cream was melted, the greater number of fat 

 globules were present in aggregates of such size that tliey could easily 

 be observed. For this reason, less efficient dispersion during homogeniza- 

 tion resulted. 



That the whipping ability of mixes is partially lost when frozen cream 

 is used as the source of fat was found to be true. In a typical trial 

 with a sweet cream mix, the maximum overrun obtainable was found to 

 be 130 per cent and was secured in 13 minutes. After 3 minutes at this 

 overrun, the percentage began to decrease. In the case of a frozen cream 

 mix of the same composition, a maximum overrun of only 118 per cent 

 was secured after 19 minutes in the freezer. 



Rate of Melting Affects Freezing Time 



The rate of melting frozen cream has an effect on the whipping prop- 

 erties of an ice cream mix made from it. With the exception of this 

 part of the study, frozen cream to be used was allowed to melt slowly 

 at room temperatures. The practice of wetting the outside of the cans, 

 so as to prevent a layer of frost from forming, was found to help some- 

 what. In this part of the experiment, frozen cream mixes made from 

 cream melted in the above manner were compared with others containing 

 frozen cream melted rapidly. In the latter, frozen cream was placed 

 directly in the pasteurization vat and heat was applied. 



Figure 2 shows that melting tlie cream slowly was more satisfactory. 

 The mixes made from cream melted slowly reached 9.5 per cent overrun 



Figure 2. 



The Effect of the Rate of Melting Frozen Cream on the Wliipping 

 Properities of Ice Cream Mixes. 



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