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5 eS ARE 
94 BULLETIN 581, U. S. DEPARTMENT OF’ AGRICULTURE. 
isms counted is 1/80X1/10, or 1/800 emm: With the usual dilution 
of one part of product to two parts of water the actual volume in 
which the number of organisms is determined is 1/3 of 1/800 emm or 
1 
1/2400 cmm, or 2,400,000 CE: 
SUMMARY. 
Tomato products promptly made from stock judged acceptable by 
visual inspection never show high counts of microorganisms. Simi- 
larly, products made from stock obviously not good or from stock 
improperly handled usually show high counts. It may therefore be 
assumed that high counts of organisms in such products indicate 
unmistakably that the stock used was in bad condition or was han- 
dled in an insanitary manner during manufacture. 
It was found that tomato pulp stored in barrels usually gave high 
microscopical counts; hence it would seem inadvisable to use barrels 
for storing the product. 
Field work performed during the past three seasons has proved that 
with proper equipment and factory management there is no reason for 
stockready for the cyclone to contain over 1 per cent of decayed material. 
In factories where the stock is properly handled the mold count is 
of greater importance than the counts on the other organisms in 
judging the condition of the raw stock. High counts of yeasts and 
spores, and bacteria are more frequently an indication of secondary 
than of primary spoilage. A low mold, yeast and spore, or bacterial 
count does not necessarily indicate sound stock, but a high count in any 
of these organisms always indicates bad stock or improper handling. 
It was found that of the samples made in the laboratory none with 
less than 5.5 per cent of rot gave a mold count of more than 50. 
In the case of the factory samples the mold count rises sharply from 
0 to 1/2 per cent of rot. - Beyond 1/2 per cent the rate of rise grad- 
ually decreases, until after 20 per cent of rot the rate of increace is 
slow. A mold count of 40 may be obtained in samples having any 
amount of rot between 2.2 and 100 per cent. 
A yeast and spore count of 20 represents about 1 per cent of decay. 
From this point the rate of increase is slow. 
A bacterial count below 15,000,000 indicates little as to the amount 
of decay. Beyond this point, however, up to 20 per cent of rot the 
rate of increase is about 20,000,000 for each per cent of rot. 
An investigation of the manufacture of tomato sauces and pastes 
in Italy showed that Italian products should be equal to American 
products made under similar conditions. The mold count for the 
concentrated products was found to be about the same as that for 
pulp, and the yeast and spore and bacterial counts to be proportional 
to the degree of concentration. Sauces and pastes made from objec- 
tionable material run particularly high in yeasts, spores, and bae- 
teria. High counts on this class of products, then, indicate bad stock 
or insanitary handling. 
O 
