ANNUAL REPORT, 1947-48 55 



browning of foodstuffs. A method was evolved for the determination of carbon 

 dioxide production in foodstuffs and in reaction mixtures. AH foodstuffs examined 

 produced carbon dioxide spontaneously on incubation. Some of the melanoidin 

 pigments resulting from the reaction between glucose and glycine were isolated^ 

 and the degree of pigment production in this system correlated with carbon di- 

 oxide production. The Maillard type of reaction was not restricted to amino 

 acids, but reactions of a similar nature were found to occur between glucose and 

 carboxylic acids in general. Oxygen was found to be an important factor in the 

 development of color, and sulfur dioxide was an effective inhibitor of browning. 

 Color produced as a result of caramelization was insignificant as compared with 

 the glucose-carboxylic acid reaction. 



The Preservative Effect of Mustard on Fruit Juices. (S. G. Davis, Omer 

 Kosker, and C. R. Fellers.) An investigation was conducted to study the preser- 

 vative effect of mustard on fruit juices. Apple and grape juice were selected as 

 test media and the relative effects of the active principles of common mustard 

 seeds were investigated as well as of synthetic and natural oil of mustard. The 

 minimum amount of mustard and mustard oil necessary for preserving the juices 

 at varying temperatures was determined. The changes in chemical composition 

 of the juices, as well as in their flavor and appearance, occurring under varying 

 storage conditions were also investigated. 



The inhibitory effects of mustard and mustard oil on typical spoilage organisms 

 were determined by inoculating the sterile juice with typical spoilage organisms. 



The active principle of mustard, allylisothiocyanate, had definite preservative 

 effect on the fruit juices tested. 



Processing Methods for Home-Canned Fruits. (Cooperative Project with the 

 Bureau of Jiuman Nutrition and Home Economics, U. S. Department of Agri- 

 culture.) (W. B. Esselen, Jr., and N. W. Desrosier.) Heat penetration data on 

 home-canned fruits obtained during the summers of 1945 and 1946 were analyzed, 

 and a theoretical "run" representing the slowest heating and the fastest cooling 

 characteristics was established for each of the following products, in pint and 

 quart jars, for water bath and for 1, 5, and 10 pounds steam pressure processing: 

 rhubarb, strawberries, cherries, raspberries, blueberries, peaches, apple sauce, 

 tomatoes, and tomato juice. 



Preliminary work showed that the use of pressure processing of fruit products 

 significantly reduced the processing time required to j'ield a given sterilization 

 value. The use of 1 pound steam pressure in place of water bath processing re- 

 duced the process times 25 to 35 percent, higher pressures decreasing the process 

 to partial "come-up times." This is due to the lethality of temperatures over 

 212° F., when based on organisms with F 212 of 1.0 or less. 



Work with water bath processes showed that the use of high initial temperature 

 (160°-170°F.) in comparison with temperatures in the range of 100°F. reduced 

 the process times 50 to 75 percent. 



The fruits processed under 1 pound steam pressure were organoleptically 

 superior to those processed for greater periods of time in the water bath, both 

 yielding the same sterilization value. 



Home-Canned Baked Beans, Hominy, and Irish Potatoes. (Cooperative 

 Project with the Bureau of Human Nutrition and Home Economics, U. S. De- 

 partment of Agriculture.) (W. B. Esselen, Jr., N. Vanasse, N. W. Desrosier, 

 and A. Sizer.) Work is being carried on to obtain information on the process 

 time requirements for home-canned baked beans, hominy, and Irish potatoes 



