BULLETIN" 740, IT. S. DEPARTMENT OF AGRICULTURE. 



SERIES III. 



Since the amino acids present in oysters had been regarded as 

 decomposition products, it was assumed that their amounts would be 

 at a minimum in oysters fresh from the beds, and would increase with 

 the length of time the oysters were out of the water. As some of the 

 experiments indicated that this was not the case, the following series 

 of experiments was carried out. 



By means of a portable apparatus carried aboard an oyster boat, 

 amino-acid determinations were run upon liquors and meats of oysters 

 as they came from the water at Princess Bay, New York. Two 

 bushels of the same stock were transported to the laboratory at 

 South Norwalk the same night. Determinations were run upon 

 representative samples of this lot every day for six days, the oysters 

 being shucked in the laboratory immediately before analysis. On the 

 last day, analyses were also run upon a lot of shell oysters from the 

 same locality, which had been stored in the laboratory in baskets for 

 four weeks. The results of this series are given in Table 3. 



Table 3. — Percentage of amino-acid nitrogen present in meats and liquors of shell 

 oysters, and its variation with age. 



Date. 



Meats. 



Liquors. 



Remarks. 



1914. 

 Nov.30 



Dec. 1 



Per cent. 

 0. 1938 

 .1970 

 .1976 

 .1640 

 .1626 

 .1709 

 .1709 

 .1737 

 .1647 

 .1645 

 .1594 

 .1651 

 .1651 

 .1720 

 .1728 



Per cent. 

 0. 0588 

 .0625 

 .0598 

 .0336 

 .0353 

 .0280 

 .0263 

 .0224 

 .0258 

 .0380 

 .0342 

 .0302 

 .0300 

 .0370 

 .0377 



Perfectly fresh. 



Oysters immediately after dredging. 



2 





3.. 





4 





5 





5 



Oysters from same locality stored in laboratory 4 weeks. 







This series leaves no doubt that the percentage of amino acids in 

 perfectly fresh oysters is much greater than has been supposed. 

 This value decreases to a minimum in the first day or two that the 

 oysters are out of water, and remains practically constant as long as 

 the oysters remain in the shell but do not lose shell liquor. Shortly 

 after losing the shell liquor from any cause death ensues with 

 attendant decomposition. 



As no further work was done on this very interesting point, no 

 conclusions can be drawn at this time. This series seems to indicate, 

 however, that some reason other than decomposition must be sought 

 to explain the presence of amino acids in fresh oysters. 



