Results presented in Table 1 show that among the traditional
antimicrobials tested in orange and apple juices, supplementation
with 1000 ppm benzoate resulted in the significantly greatest
inactivation of t5D value of the test pathogen. In both juices, the
reduction in the t5D values due to the combination of benzoate and
sorbate were not significantly different from those of benzoate
alone. It should however be noted that despite having the least
efficacy, supplementation of 1000 ppm sorbate in both orange and
apple juices similarly resulted in significant reductions in the t5D
values of E. coli O157:H7, compared to the non-supplemented
controls. Greater individual antimicrobial efficacy of benzoate and
its combination with sorbate compared to the efficacy of sorbate
alone against E. coli O157:H7 in refrigerated apple juice have been
similarly reported by Zhao, Doyle, and Besser (1993). Furthermore,
Splittstoesser, McLellan, and Churey (1996) reported that in
additive-free apple cider, supplementation of 1000 ppm benzoate
was 8 times better in reducing the heat resistance of E. coli O157:H7
at 50 C than 1000 ppm sorbate. Benzoate was also observed to be
2e3 times as effective as sorbate in decreasing the heat resistance
of E. coli O157:H7 in apple juice (Steenstrup & Floros, 2002).