I9I3] 



Clayton S. Smith 



67 



By this method a reducing power of 2.32 per cent. was reported for 

 the plaice (Pleuronectes platessa). 



Our own method failed to show any reducing power. Artificial 

 hydrolysis was avoided. We were unable to get satisfactory 

 responses to our qualitative tests for the presence of sugar in 

 protein-free extracts, both from fresh and storage fish. For a com- 

 parative test, glucose, to the amount of o.oi per cent., was added 

 to one of the extracts, and a characteristic reduction obtained. For 

 the quantitative determination of small amounts of sugar in meat, 

 Bauer^^ recommends a spectroscopic method, since the Polarimetrie 

 and titrimetric processes are unreliable for amounts less than 0.5 

 per cent. As no sugar was detected qualitatively, either before or 

 after cold-storage, it seemed quite certain that no appreciable 

 hydrolysis of glycogen had taken place. 



Quantitative reaction of aqueous extracts. The reaction of 

 aqueous extracts was always found to be acid to both litmus and 

 Phenolphthalein. From the data in the tables it is evident that the 

 acidity of the aqueous extract was not materially affected by long 

 periods of cold-storage. In several instances the same extract was 

 titrated after Standing for from two to four days in an ordinary 

 house refrigerator. In each case the Variation in acidity was within 

 the Hmits of error of the method itself. 



The general analytic results of our work are summarized in 

 Table 4. 



TABLE 4 



Summary of general average data 



21 Bauer: Arb. a. d. kais. Gesundhsmt, 1908, xxx, p. 63. 



