We found that RH values significantly affected the survival of
E. coli O157:H7 and S. Typhimurium on all three apple surfaces at
temperatures of 4 C and 15 C. However, RH did not significantly
affect the growth of different Salmonella types when incubated at
25 C on tomato surfaces (P > 0.05) (Shi et al., 2007). This difference
may be due to the difference in storage temperatures. Iturriaga et al.
(2003) found that the combination of temperature and relative
humidity had a significant effect on the attachment of Salmonella
Montevideo to the surfaces of tomatoes and tomatillos. In studying
the effects of surface condition on the survival of pathogens, Ells
and Truelstrup Hansen (2006) found that the condition of cabbage
surfaceswas an important factor for pathogen attachment and
that colony counts from cut surfaces were significantly higher
compared to those of intact surfaces. In our study, there was not a
reduction in pathogen levels on cut apple surfaces for all RH levels.
In other words, surface condition was an important factor for
pathogen survival. We concluded from these results that RH levels
and surface conditions were related to the survival of pathogens
contaminating the surface of fresh fruits. As such, fresh fruits
should be stored, prepared, and processed in refrigerated conditions
with low RH. It is also important to avoid damaging the surface
of the fruit to enhance the safety of its consumption.