88 BULLETIN 433, U. S. DEPARTMENT OP AGRICULTURE. 



of the exposed muscular and fatty tissues. The shrinkage in weight 

 varied from 2.15 per cent in the case of the beef held in cold storage 

 for 14 days to 10 per cent in that held in storage for 177 days. Slight 

 growths of mold appeared on the exposed muscular tissues in the 

 middle stages of this series of experiments, but did not become exten- 

 sive even in the case of the beef stored for 177 days. In fact the 

 progressive drying out of the meat during storage inhibited the 

 growth of mold. The hardening and darkening of the tissues of the 

 meat, together with its shrunken appearance after the longer periods 

 of storage, undoubtedly lowered the market value of the product, en- 

 tirely apart from any question as to its wholesomeness or nutritive 

 value. On the other hand, the physical changes which took place in 

 the beef stored for 2 and 4 weeks, periods which correspond to the 

 length of time that beef is held in cold storage in commercial prac- 

 tice, were not' marked and did not lower the market value of the 

 product. 



In the experiment which was carried on in the packing-house 

 cooler, where the temperature was slightly lower and the humidity 

 much higher than in the bureau's cold-storage room, the shrinkage in 

 the weight of the beef at the end of the 54-day storage period 

 amounted to 3.27 per cent, as compared with 5.26 per cent in the case 

 of the beef stored in the bureau's cooler for only 28 days. 



The beef stored in the packing-house cooler was covered with a 

 heavy growth of mold after 54 days in storage, so heavy, in fact, that 

 it appeared that the meat could not be carried safely in storage for a. 

 longer time, and the experiment was concluded. The beef was con- 

 sidered still to be in marketable condition. The lowered shrinkage 

 and the increased growth of mold noted in this experiment were un- 

 doubtedly the result of the greater humidity of the packing-house 

 cooler, as compared with that of the bureau's cold-storage room. 



ORGANOLEPTIC PROPERTIES OF THE BEEF, 



The principal effect of cold storage upon the organoleptic proper- 

 ties of the beef was a marked increase in tenderness; but the extent 

 of this change did not bear a direct relation to the length of the 

 storage period. In fact, the increase in tenderness of beef stored 

 for from 2 to 4 weeks was practically as great as that in beef stored 

 for much longer periods of time. 



Although flavor is one of the qualities of meat in the judgment of 

 which individuals may differ greatly, yet it was the opinion of the 

 authors that, on the whole, storage did not improve the flavor of the 

 meat. Storage caused a gradual change of flavor to the extent that 

 the beef stored for the longer periods of time was designated as 

 " old," and was considered in some cases to be less appetizing than 

 the flavor of fresh meat. Similar changes were noted in the odor of 

 the freshly cut surfaces of the cold-storage meats. 



