STUDIES OF CRANBERRIES DURING STORAGE. 85 



It is evident from the results that Howes was the only variety that 

 would keep well enough to make storage possible until midwinter in order 

 to extend the marketing season. The other varieties, however, are better 

 in eating quaUties, and might be used for the manufacture of jam and 

 jelly in seasons of abundant crops. 



Cranberry Vinegar. 



In September, 1918, an early frost injured many acres of cranberries, 

 and the question was asked of the Experiment Station whether it was pos- 

 sible to utilize the frosted fruit as a source of vinegar. Consequently a lot 

 of the frozen berries was secured by Dr. Franklin for the preparation of 

 some juice for a fermentation experiment. It was found impossible with 

 a machine to separate rotten berries from the fruit softened by the frost, 

 and the cranberries were used without sorting. 



The juice was pressed from the berries early in October by means of 

 a hand cider mill. A lot of juice from sound fruit was prepared at the same 

 date for comparison with regard to qualit}''. Both lots of juice possessed a 

 very disagreeable, bitter, acid taste. They remained under favorable 

 conditions for fermentation until December 19, when they were received 

 at the chemical laboratory for analysis. 



Careful tests were made for alcohol in the juice by repeated distillation 

 to concentrate it, and the application of the iodoform reaction to the final 

 distillates. Neither juice showed more than a trace of alcohol in the final 

 reaction, so that little fermentation had occurred. 



Total acid and total sugar were determined in the different juices by 

 the methods employed for the cranberry analyses. The results were found 

 to be 2.3 per cent acid and .8 per cent of sugar in the juice from frozen 

 berries, and 2.9 per cent acid and 2.6 per cent sugar in the juice from 

 sound berries. Had the sugar all fermented to acid there would not have 

 been sufficient strength to make a legal vinegar, while the taste would 

 condemn its use in any case. Freezing resulted in a marked lowering of 

 sugar in the fruit. The failure to ferment freely is probably due to the 

 benzoic acid, which is a natural constituent of the cranberry. It does not 

 appear practicable to utilize waste cranberries for vinegar. 



Summary. 



This bulletin reports the results of a chemical investigation made on 

 the changes taking place in stored cranberries. 



After the cranberries are picked from the vines they still remain living 

 organisms. Storage conditions should be such that the life of these organ- 

 isms may be prolonged instead of death being hastened. 



Cranberries lose some of their sugar during storage. This loss is due to 

 the respiration of the li\ing berries, which respiration is less rapid at low 

 temperatures than at high temperatures. For this reason the warmer the 

 berries are kept the greater the loss of sugar during storage. 



