HOME REFRIGERATION 17 



Spoilage of Left-over Foods 



In 76 samples of food stored for five days at approximately 41°F., only seven 

 cases of spoilage were detected organoleptically. Six of these spoiled samples 

 were sliced tomatoes, the other was snap beans which spoiled in a covered dish 

 in five days. The only uncovered sample which spoiled was sliced tomatoes, where 

 detectable signs of spo'lage were noted after four days. 



Bacteria counts were made on some stored left-over foods. None of the samples 

 tested showed visible signs of spoilage. In storage periods up to five days, only 

 slight increases in the number of microorganisms were observed. However, in 

 many cases there was a decided increase in the number of bacteria present in the 

 samples after storage for seven days. 



Discussion 



The need of co\'ering refrigerated foods is appreciated when it is considered 

 that in only two days one-tenth of the weight of the food has evaporated into the 

 air. 



Considerable attention has been paid to the dehydration of foods in commercial 

 cold storage, because a loss in weight means a loss of money. On the other hand, 

 in home refrigeration the drying-out of the surfaces of the food and loss in quality 

 are of primary importance. 



The vegetables stored with juice lost approximately the same amount of 

 weight as those without. It, therefore, seems probable that most of the evapora- 

 tion occurred on the surfaces of the vegetables. In cases where juice was present, 

 the vegetables probably acted as a wick. This seems reasonable when the large 

 surface of the exposed vegetables as compared to that of the liquid is considered. 



It should be noted that even at humidities of 80 to 84 percent there was as 

 much as 10 percent loss of weight in four days. It was, therefore, found advisable 

 to cover all left-over foods to prevent loss of moisture and deterioration in quality. 



Plausible reasons for the apparent increase in vitamin C content would appear 

 to be formation of some substance which reduces the indophenol dye, sampling, 

 or the possible production of ascorbic acid-like substances by microorganisms, 

 or a breakdown of a complex ascorbic acid compound in the food. As stated 

 previously, changing the method of sampling did not eliminate these increases. 



Storage, of the foods tested, in domestic refrigerators in covered or uncovered 

 dishes appeared to practical!}' eliminate microbial spoilage for at least five days. 

 H'gh storage humidity did result in spoilage of sliced tomatoes but as they are 

 seldom, if ever, stored in the home, this is of no practical significance except that it 

 demonstrated the eft^ect of high humidity on the growth of microorganisms. This 

 was supported by the plate counts of two of the foods. 



FLAVOR TRANSFER IN HOME REFRIGERATORS 



Canned crab meat and salt codfish were used as contaminating substances; 

 unsalted creamery butter and processed creana cheese were used as flavor ab- 

 sorbers. 



The flavor emitters were stored on the middle shelf of the refrigerator while 

 the absorbers were placed in corresponding positions on the bottom shelf. Un- 

 covered and covered dishes of various t>'pes were used for storage of the butter 



