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UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 740 
Contribution from the Bureau of Chemistry 
CARL L. ALSBERG, Chief 
Washington, D. C. V January 13, 1919 
A STUDY OF SOME OF THE CHEMICAL CHANGES WHICH 
OCCUR IN OYSTERS DURING THEIR PREPARATION FOR 
THE MARKET. 
By Edward E. Smith, Junior ChemistJ 
4 
CONTENTS. 
Page. 
Scope of investigation. 1 
Commercial treatment of oysters. 2 
Experimental work. 3 
Methods of analysis. 3 
Series 1. 4 
Series II. 6 
Page. 
Experimental work (continued): 
Series III. 8 
Series IV. 9 
Series V. 13 
Summary. 23 
SCOPE OF INVESTIGATION. 
This bulletin gives the results of an investigation to determine the 
amounts of ammoniacal nitrogen, amino-acid nitrogen, moisture, 
total solids, ash, and sodium chlorid present in oysters under the 
various conditions through which they pass in ordinary commercial 
practice in the oysterhouse, and to ascertain the effect of washing 
and soaking on both the chemical composition and physical condition 
of the oysters. The investigation was conducted during the fall and 
winter of 1914 - 15 , in certain oysterhouses in Connecticut, selected 
as being representative of the oyster industry throughout the North 
Atlantic States. The oysters used were grown in various beds, rang¬ 
ing from New Haven, Conn., on the east, to Raritan Bay, N. J.' on 
the west. As work was done in several houses, each using a different 
method of treatment of the stock, the methods given represent 
commercial practice at that time and in that locality, hut may not 
be representative of later practice or other localities. The experi¬ 
ments which were made to show the results of various special treat¬ 
ments do not represent commercial practice. 
1 The writer wishes to express his indebtedness to Dr. E. D. Clark and Mr. L. H. Almy, who instructed 
him in the methods of determination of ammoniacal nitrogen and amino-acid nitrogen; to Mr. Carleton 
Bates and Dr. Lester Round, who assisted materially in planning the work and under whose direction 
it was carried out; and especially to Mr. R. W. Lamson, without whose help Series V would have been 
impossible. 
77345°—19—Bull. 740 1 
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