12 
BULLETIN 740, U. S. DEPARTMENT OF AGRICULTURE. 
It had been assumed previously that the composition of oysters in 
the shell would be identical with that of oysters taken from the 
shuckers’ dippers. Table 4 shows that this is not the case, that 
there is a slight but well-defined difference in composition. The 
percentage of total solids and other constituents except water is 
greater in the samples from the shuckers than in the sample of the 
same stock shucked in the laboratory immediately before analysis, 
while the percentage of water is correspondingly less. This difference 
probably is due to the fact that the oysters drain for half an hour or 
more while in the shuckers’ dippers, and tend to lose a certain amount 
of their body fluids, shell liquor, and adhering mucus. The shell 
stock, being opened in the laboratory, had had less time in which to 
lose water, and, therefore, was always poorer in solids., This marked 
difference in composition between oysters which it would seem at 
first glance should be of identical composition, shows very plainly 
that the stock for each determination must he handled in exactly the 
same way every day if the results are to be comparable. 
Table 4 is of great interest in showing the composition of oysters 
during the various stages of progress through the oysterhouse, and 
it shows also in a very striking manner the difference between the 
old and the new methods of washing oysters, to the discredit of the 
new methods, if amount of total nutrients is a proper criterion. 
With the purpose of plainly showing this difference, the table has been 
arranged in two parts, the analyses of oysters washed by the modern 
method of air agitation in tanks and the analyses of stock washed by 
the old method upon a perforated skimmer. 
Of the substances determined, amino-acid nitrogen and total solids 
are taken for comparative purposes, as they are the most consistent 
determinations made and most clearly represent the condition of the 
oysters examined. The amino-acid nitrogen represents a truly 
soluble constituent which would be dissolved out of the oysters by 
the wash water. The total solids, though including most or all of the 
amino-acid nitrogen, are in the main insoluble substances whose 
apparent diminution in quantity is due largely to the distention of the 
bodies of the oysters because of osmosis and loss of particles of solid 
meat in handling or washing. A glance at the average values of 
amino-acid nitrogen and total solids for the two classes of washing 
shows that the content of both is much higher in oysters washed by 
the old method than in those washed by the modern one. A brief 
analysis of the results will show exactly how the two sets of figures 
compare. Taking the amount of each of these substances present in 
the shell stock as a basis upon which to calculate the losses, this 
figure may be called 100 per cent. Thus, the amounts of each of the 
constituents are expressed in percentages of the amount present in 
the same stock while in the shell. For the shucked stock and the 
commercial package, then, the figures in Table 5 are obtained. 
