CHANGES Itf FRESH BEEF DURING COLD STORAGE. 5 
COMMERCIAL RIPENING OF MEATS. 
The term " ripening," or " ageing," as applied to fresh beef, de- 
notes the practice of holding such meat in cold storage at tempera- 
tures above freezing for various periods of time for the purpose of 
improving the quality of the meat, it being the opinion of experts 
that the ripening of beef greatly improves its quality, particularly as 
regards tenderness. This practice is not followed to any extent by 
the larger packing houses on their own account, but it is carried on 
to a certain extent by concerns which supply meats to high-class 
hotels and restaurants and to the dining-car service. As a rule, such 
concerns do not ripen meats in their own coolers, but select their cuts 
of meat and have them ripened in coolers belonging to the larger 
packing houses. 
The practice of ripening meats is a simple one. Suitable cuts of 
meat, usually heavy, fancy ribs and loins and occasionally entire 
hind quarters, are hung in a cooler set aside for the purpose, or in a 
regular beef cooler, for from two to six weeks, depending upon the 
degree of ripeness desired. A dry cooler with good circulation of 
air is preferred, and the temperature is ordinarily held at 34° F. 
Depending upon the condition of the cooler as regards temperature 
and humidity, cuts of meat may show a slight growth of mold after 
from two to three weeks, and a heavy growth after from four to 
six weeks in storage. The growth of mold appears first and is 
heaviest on the cut surfaces of the meat. The degree of ripeness is 
judged largely by the length of the " whiskers," as the growth of 
mold is called in packing-house parlance. Such meats are wiped free 
of mold when sold; and the purchaser must assume any loss due to 
the necessity for trimming. As compared with the total amount of 
chilled beef handled in this country the quantity of specially ripened 
beef is quite small. 
PREVIOUS INVESTIGATIONS ON COLD STORAGE OF MEATS. 
Only a brief discussion of the more important cold-storage investi- 
gations will be attempted. 
Gautier (1897) 1 was one of the earliest workers to carry on ex- 
tensive investigations concerning the changes which take place in 
meats during cold storage. He studied the chemical, physical, and 
organoleptic properties of fresh (French) beef and mutton as com- 
pared with frozen (Argentine) beef and mutton that had been held 
in cold storage between 5 and 6 months at —3° to —5° C. Artificial 
digestion experiments were also carried on. In general, the conclu- 
sions reached were to the effect that there was little difference in the 
composition of the fresh beef and mutton as compared with the 
1 References to literature will be found on page 100. 
