| Summary: | 碩士 === 國立臺灣大學 === 食品科技研究所 === 86 === Egg products such as steamed egg was one of the main vehicles
of food-borne pathogens Salmonella spp., S. aureus, E. coli
O157:H7 and Listeria monocytogenes can grow in the egg
products. These pathogens are frequently reported to causes
food-borne out breaks in many countries. Growth behavior of
these food-borne pathogens in egg products stored at different
temperatures were investigated in this study. Data obtained
will provide valuable information to develop the proper storage
condition and to assume the
The results revealed that regardless of inoculation size, no
significant growth of Salmonella spp., S. aureus, and E. coli
O157:H7 was observed in steamed eggs and Scrambled eggs stored
at 5℃for a period of 36 hr. However, a slight growth of L.
monocytogenes was noted in the egg products.
The test organizations showed different extents of growth in
egg products when stored at 18, 22 and 37℃. In general, the
growth rate was highest in egg products stored at 37℃.Both
steamed and scrambled eggs can supply adequate nutrients
support the growth of the organisms tested, Among the organisms
tested, S. aureus was found to grow best in egg products,
followed in deciding order, by Salmonella spp., E. coli O157:
H7, and L. monocytogenes. In general, the growth of test
organisms was better on steamed e
Enterotoxin was detected from the steamed eggs and scrambled
eggs which have been inoculated with S. aureus and stored at
37℃ or 22℃for various periods of the time. During the storage
period, the higher the original inoculation size of S. aureus,
the earlier the enterotoxin was detected from the egg products.
The amount of enterotoxin detected in egg products increased as
the storage time increased.
Stimulation of heat resistance capability by heat shock depends
on the kinds of microorganisms tested and the temperature of
the subsequent heat treatments. Although heat shock was found
to increase the heat tolerance of E. coli O157:H7, Salmonella
spp. at 55℃ and 60℃, this heat treatment did not increase the
heat resistance of E. coli O157:H7. On the other hand, the heat-
shocked L. monocytogenes showed less subsceptle at 55℃while
was more susceptle at 60℃than the non heat shocked cells.
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