ANNUAL REPORT, 1032 25 



> It is evident from yield records of several varieties that there is a correlation 

 between a high percentage of pollen germination and high yield, in spite of the 

 fact that it would seem reasonable to assume that even the varieties with poor- 

 germinating pollen would disseminate sufficient pollen to meet all "set" require- 

 ments. 



DEPARTMENT OF DAIRY INDUSTRY 

 J. H. Frandsen in Charge 



Frozen Fruits and Their Utilization in Frozen Dairy Products. (M. J. 



Mack and C. R. Fellers, Horticultural Manufactures.) This cooperative project 

 has been active for three years. A full report of the investigation has been pub- 

 lished in Bulletin 287. 



The Vitamin C Content of Strawberry Ice Cream Containing "Frozen 

 Pack" Fruit. (C. R. Fellers, Horticultural Manufactures, and M. J. Mack.) 

 This study was planned to determine the Vitamin C potency of fresh strawberries, 

 frozen packed strawberries, and strawberry ice cream. It was conceivable that 

 Vitamin C might be partially destroyed either in the process of freezing, during 

 storage, or in the rigorous beating of ice cream in the ice cream freezer. However, 

 the data collected by feeding tests on guinea pigs indicate no destruction of Vita- 

 min C either in the frozen storage of strawberries or in the preparation and storage 

 of strawberry ice cream containing the frozen pack fruit. Thus strawberry ice 

 cream may be considered a source of Vitamin C. 



A Study of Ice Creams High in Fat Content. (M. J. Mack.) More data 

 have been accumulated on this subject during the past year. Ice creams varying 

 in fat content from 20 to 30 per cent are now being made by many New England 

 manufacturers. Such ice creams vary markedly in character from the usual 

 commercial product in which the fat content invariably lies between 10 and 20 

 per cent. 



The most serious problem which is encountered in the making of high-fat ice 

 creams is to control the viscosity of the mix. An excessive viscosity usually re- 

 sults which interferes with certain processes in making the mix, as well as with 

 freezing and packaging of the product. Some sources of fat prove to be much more 

 satisfactory than others in the control of viscosity. The findings thus far would 

 indicate that, in the making of ice creams high in fat content, the percentage of 

 non-fatty ingredients, as well as processing and freezing procedures, must all be 

 altered wherever possible to bring about lower viscosity of the mix. 



The Effect of High Initial Aging Temperatures on Certain Physico- 

 Chemical Properties of Gelatin Dispersions. (\V. S. Mueller.) The purpose 

 of this investigation was to determine what effects various high initial aging temp- 

 eratures have, when used for definite periods of time, on the basic viscosity and 

 gel strength of gelatin dispersions. A gelatin-ice cream mixture, pure gelatin- 

 water solution, and other gelatin dispersions such as cane sugar, butter oil, and 

 plasma solids, were used. This study has been completed and a paper prepared 

 for publication. 



The following conclusions have been made: 



1. When using a gelatin-ice cream mixture — - 



(1) Initially aging an ice cream mix for 1 to 6 hours at temperature range 

 of 10° to 30° C. (50° to 86° F.), followed by a low aging temperature, increased 

 the basic viscosity and gel strength over those mixes aged at the low temperature, 

 2.2°C. (36°F.) only. 



