Abstract This paper investigated the feasibility for pasteurizing
raw (100 %) pomegranate juice in a commercial scale
pulsed electric field (PEF) processing system. The juice was
processed at 35 and 38 kV/cm for 281 μs at 55 °C with a flow
rate of 100 L/h. Effect of PEF processing on microbial stability,
color, °Brix, pH, sediment, antioxidant activity, total phenolic
content, anthocyanin, and sensory properties after the
treatments and during storage at 4 °C for 12 weeks were
studied and compared to those of thermally processed juice.
PEF treatments significantly (p <0.05) inhibited the growth of
total aerobic bacteria, which remained at <2.5 log colonyforming
units (CFU)/ml during the 12-week storage. No yeast
and mold were detected (<0.69 log CFU/ml) in the PEFtreated
juices during storage up to weeks 10 and 12, which
is similar to the thermally processed juice. There were no
significant differences in pH and °Brix values between the
PEF processed juice and unprocessed juice. PEF processing
did not alter the contents of total phenolics and anthocyanin as
compared to unprocessed juice. PEF processing had significantly
(p <0.05) less impact on the color of pomegranate juice
than thermal processing. PEF-treated juice had the same consumer
satisfaction scores as the unprocessed juice,which were
significantly (p <0.05) higher than thermally processed juice
samples. There was no significant difference between the two
PEF treatments in all results. This study demonstrated that
PEF technology extended microbial shelf-life and preserved
the major quality and nutritional characteristics of pomegranate
juice, and hence, is technically feasible for commercialization
in the juice industry.
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