The inhibitors of enzymatic browning most frequently used
in industry include acid or brine dips, ascorbic acid (AA), and
various forms of sulfite-containing compounds. The latter have
applications for a broad range of produce and are strong antibrowning
and antimicrobial agents. However, in addition to
causing off-flavors, sulfites pose health risks to allergic individuals
and, consequently, their application on fresh and freshcut
produce was banned by the U.S. FDA (6). AA and its derivatives
are frequently added to acidic dips used for the pretreatment
of peeled or sliced fruit to prevent the oxidative browning
of fruit juice prior to pasteurization (7). However, browning
proceeds after the depletion of ascorbic acid (4). Furthermore,
AA and its derivatives, unlike sulfiting agents, do not have antimicrobial
activity, and thus a sanitizer should be used in conjunction
with the antibrowning agent to reduce the potential
pathogen contamination and spoilage microorganisms developed
during the storage of produce. Unfortunately, most sanitizers
used in the produce industry are incompatible with most antibrowning
agents because they tend to be oxidizing agents,
whereas most browning inhibitors tend to be reducing agents.
Consequently, in combination they usually cancel out each
other’s desired effects, jeopardizing product safety. Recently,
the largest fresh-cut apple processor experienced a costly recall
of their products due to the detection of human pathogenic
bacteria by the FDA (8). To maintain food safety and quality
of fresh-cut apples, a sanitizer that is compatible with the
currently widely used antibrowning solution or, better yet, a
solution that can provide dual control of browning reaction and
microbial growth is urgently needed.