14 



Transactions 



Chemical Experiinent No. 5. — For Detection of Enzymes. 



Dr. Rideal, in a paper before the first Refrigeration Congress, suggests 

 that the tenderness and maturing of cold-storage meats are due to the 

 gradual and limited work of natural enzymes, such as pepsin and trypsin, 

 present in the flesh, which cause a certain amount of predigestion similar 

 to that occurring when fresh meats are kept or " hung." In the chemical 

 experiments under review the enzymes detected were peroxydase, catalase, 

 and an enzyme similar to trypsin, a protase. These were found in both 

 the mutton and lamb from to 160 days in cold storage, and were also 

 found in the thymol- and chloroform-treated material. 



Negative results were found in testing for invertase, lipase, and 

 diastase. 



Importance is attached to these results, for while enzyme activity goes 

 on slowly at low temperatures, yet the action is not prevented by cold, 

 and undoubtedly the changes found in cold-storage meats are due to the 

 action of the enzymes, especially the trypsin-like protase. The experi- 

 ments are recorded as Chemical Experiment No. 5. 



X = present. 



absent. 



Chemical Experiment No. 6. — To determine the Acidity of the Fat. 



The development of acidity in fat is a delicate indication of the de- 

 ■Tcomposition of flesh, and one that can be observed long before the senses 

 can detect any alteration. Applying this test to the fat of the mutton 

 and lamb, we find from the results shown in Chemical Experiment No. 6 

 that no material rise in the free fatty acidity is observed ; consequently 

 we can infer that no decomposition has taken place. 



Chemical Experiment No. 6. — Showing Acidity of Fats. 



