ANNUAL REPORT. 1930 267 



Several types of equipment designed to determine tlie jelly strength of 

 Jellies have been compared. Work is being done on the development of 

 a new jelly tester similar in construction to the Magness fruit pressure 

 tester. 



Manufacture and Preservation of Cranberry Products. (C. R. Fellers, 

 J. A. Clague, and W. W. Chenoweth). Close cooperation with the Ameri- 

 can Cranberry Exchange and the commercial cranberry preservers has 

 been maintained. The use of the Abbe refractometer for determimng 

 the proper finishing point in cranberry sauce manufacture has been intro- 

 duced into all of the commercial canneries. By this means the quaRty 

 of the sauce is maintained and every batch can be standardized to a defi- 

 nite sugar content (42-44- per cent), insuring also maximum yields consis- 

 tent with optimum jelly strength. 



Frozen cranberries held at 10° F. for 1 to 12 months were found to be 

 very satisfactory for sauce manufacture, the sauce retaining all the flavor, 

 color and jelly strength of the fresh-fruit sauce. This year some of the 

 canners are freezing several thousand barrels for manufacture during 

 the off season. 



Canned cranberry sauce was shown to be impaired by freezing. The 

 jelly strength was decreased as much as 20 per cent and syneresis (bleed- 

 ing) was greatly increased. 



Researches are under way in cooperation with the State Cranberry Sta- 

 tion on the suitability of about 30 commercial varieties for canning pur- 

 poses. Strained and whole sauce is manufactured from each variety, the 

 yield, characteristics and keeping qualities being noted. 



The American Cranberry Exchange of New York, through a grant of 

 $1000, requested the department to carry on nutritional studies on the 

 cranberry. The first research attempted was a determination of the vita- 

 min C content of raw cranberries and fre.sh and canned cranberry sauce. 

 Preliminary results on 4-5 guinea pigs indicate that the raw cranberries 

 contain substantial amounts of vitamin C, but practically all is destroyed 

 by the manufacturing process. This work is being actively continueH in 

 order to evolve, if possible, a method of sauce manufacture which will 

 protect the vitamin C. Cranberry juice is also a rich source of vitamin C, 

 as little as 3 cc. per day protecting guinea pigs against scurvy for at 

 least 90 days. The use of cranberry juice as a beverage is also being in- 

 vestigated. 



Utilization of Onions by Canning. (C. R. Fellers). The examination 

 of experimental packs of canned onions made in 1929 and 1930 fully bear 

 out earlier conclusions as to the feasibility of canning onions in tin 

 cans or glass jars. Chemical studies on canned onion discoloration are 

 being conducted by the Chemistry Department. Continued tests on 

 dehydrated cull onions and the ease of manufacture of onion powder or 

 "flavor" have renewed confidence in the feasibility of utilizing cull onions 

 in this way. Preliminary experiments on preserving small onions in brine 

 for pickling purposes indicate that a 60 degree salometer brine is prefer- 

 able to lighter brines. 



Nitrogen Distribution of the Edible Portion of the Onion. (F. P. Grif- 

 fiths). This project was discontinued upon the resignation of Mr. Grif- 

 fiths on July 1, 1930. Nitrogen in the form of ammonia, nitrate, amino 

 acids and protein was determined in fresh and dried onions. 



