ANNUAL REPORT, 1947-48 51 



A 10 or 15 minute treatment in a solution containing 5 percent salt, 0.5 per- 

 cent ascorbic acid and 0.4 percent citric or ortho-phosphoric acid gave good re- 

 sults if the sliced apples were to be held for only a short time. Refrigeration is 

 essential for apple slices treated in this manner. 



For soft-textured apples such as the Mcintosh the addition of 0.10 percent 

 calcium chloride in the dipping solution is effective in maintaining the texture 

 of the slices when they are baked in pies. 



Apple-Cranberry Juice. (W. B. Esselen, Jr., K. M. Hayes, and C. R. Fellers.) 

 An attractive and palatable fruit juice can be made by blending from 12 to 15 

 percent cranberry juice with apple juice. It is necessary to give the apple juice 

 a preliminary flash pasteurization treatment in order to inactivate enzymes 

 which would otherwise destroy the red color of the cranberry juice when the two 

 are mixed together prior to final processing. The enzyme present in the apple 

 juice, which destroyed the red color of the cranberry, was inactivated by heating 

 at 190°F. for 0.5 minute or at 180°F. for 2.0 minutes. 



Pre-Packaged Fresh Cranberries. (C. R. Fellers, K. M. Hayes and W. B. 

 Esselen, Jr.) A new development in the merchandising of fresh cranberries has 

 been the packaging of the fruit in transparent bags or packages for the retail 

 trade. During the past year a study has been made of the effect of packaging in 

 small sealed containers on the keeping qualities of cranberries and of the various 

 kinds of packaging material used for the storage and marketing of the fruit. 



Of the packaging materials studied, single thickness 450 LSAT cellophane 

 was found to possess the best qualities for pre-packaging fresh cranberries. 

 This type of package had good transparency' and permitted the fruit to respire 

 slowly with a minimum loss in weight due to desiccation and respiration. Cran- 

 berries in packages stored at room temperature (65°-75°F.) could be held for 

 five to six days without appreciable breakdown, while at 35°F. the packaged fruit 

 remained in good condition for from four to five months. This type of package 

 is being adopted by several cranberry marketing agencies. 



Factors Affecting the Viability of Dried Bakers' Yeast. (R. E. Morse and C. R. 

 Fellers.) Methods for the laboratory preparation of dried bakers' yeast were 

 investigated. Yeast was prepared which was similar in chemical composition and 

 leavening properties to good grade commercial dried yeast. 



A new method for testing the viability of dried bakers' yeast with triphenyl 

 tetrazolium was developed. A carmine color, developed by reduction of the dye 

 by yeast, is extracted with acetone and measured with a spectrophotometer. 

 Good correlation between yeast viability and color development was obtained. 



Exposure to light and type of package showed little or no effect on the viabilit}- 

 of stored dried yeast. A low storage temperature and humidity had a pronounced 

 favorable effect on the retention of viability in dried yeast. Nutritional and 

 environmental factors were of paramount importance in causing yeast cells to 

 develop dormancy and longevity in the semi-desiccated state. 



The Composition and Nature of Apple Protein. (S. G. Davis and C. R. Fellers.) 

 Apple tissue was found to contain approximately 0.2 percent protein. Isolated 

 apple protein material had a nitrogen content of 8.5 percent. Amino nitrogen 

 amounted to 93.5 percent of the total nitrogen, and the 16 amino acids (leucine, 

 isoleucine, valine, phenylalanine, tryptophane, glutamic acid, alanine, histidine. 

 arginine, threonine, methionine, lysine, aspartic acid, serine, proline and cj'stine) 

 for which values could be obtained accounted for 83.6 percent of this amount. 



