January/February 2023 - 20

PRODUCE SAFETY
Safety advancements
The challenge with produce has been
developing a safe, simple means of
delivering ClO2 in a way that prevents
virus growth while protecting organoleptic
properties. Aptar CSP Technologies has
made advancements in active material
science that make it possible to address
those challenges.
A novel antimicrobial delivery system
has been developed to deliver a controlled
release of ClO2 inside the headspace of
sealed produce packages. This solution
leverages a proprietary 3-Phase ActivPolymer
platform technology to protect
against virus contamination in a manner
that is safe, effective and without an
organoleptic effect.
The technology, called InvisiShield, is
an extruded film attached to the lidding
film prior to package sealing. Once sealed,
the relative humidity in the packaging
headspace triggers a controlled release of
ClO2 over the course of approximately 12
hours (Figure 1). By controlling the rate
of the antimicrobial treatment's release,
the produce is protected against growth
of viruses and other pathogens without
any impact to taste, scent or appearance.
As the film releases the ClO2
, it breaks
down quickly and is not present in the
food product, so it doesn't need to appear
on the product's labeling. ClO2
delivered
by the novel active packaging system is
not detectable in the final product after
24 hours because it is converted into
chloride salts, which are naturally present
in the food.
A t-Test conducted by Southwest
Research Institute determined there was
no significant statistical difference in
4
3.5
3
2.5
2
1.5
1
0.5
3.63
Tomatoes
Limit of Detection
 Figure 2. Inactivation of human norovirus (HNV) on grape tomatoes and blueberries by antimicrobial
technology, expressed as log10
HNV genome equivalent copy (GEC) reduction (n=3). The dotted line
represents the limit of detection of the assay.
chloride levels found in commercially
available tomatoes compared to those that
underwent the antimicrobial treatment.
This means the breakdown of the chlorine
dioxide gas is consistent with the amount
of chloride salts naturally found in the
food. These findings confirm that the
technology qualifies for " incidental
additive " status based on 21 C.F.R. §
101.100(a)(3)(iii) threshold standards, and
it also has GRAS (Generally Recognized
as Safe) status.
The impact of antimicrobial
technology on virus growth
To confirm the antiviral effectiveness
and consumer safety of this active
packaging solution, Dr. Lee-Ann Jaykus,
William Neal Reynolds distinguished
professor & NoroCORE scientific director
at North Carolina State University,
conducted an experiment to explore the
technology's efficacy against a strain of
HNV and HAV.
For the study, grape tomatoes and
blueberries were placed in separate
polypropylene trays and inoculated
with substantial amounts of both human
norovirus and hepatitis A virus. Trays
in the virus-treated group were heat
sealed with lidding film that included
the antimicrobial treatment. Trays in
the untreated control group underwent
the same packaging process but without
the treatment.
All packages were stored at 7°C (44.6° F)
Lidding Film
ClO2
Product
Juices/Purge
 Figure 1: Diagram of Aptar Food + Beverage's InvisiShield ClO2
packaging.
20 JANUARY/ FEBRUARY 2 023
gas delivery system for modified atmosphere
for periods of zero hours (initial reading
just after the test began), 24 hours, 48
hours and seven days. At each time
point, the product was collected and
processed for virus concentration. For
grape tomatoes stored in active packaging,
human norovirus was reduced by nearly
99.99% and, for berries, reduced by nearly
99.9% (Figure 2). Hepatitis A was reduced
by 99% on the grape tomatoes and more
than 99.9% on blueberries (Figure 3).
This solution is not limited to protecting
fresh produce. As noted previously,
in recent years, concerns have arisen
regarding virus growth, including strains
2.70
Berries
log10
HNV GEC Reduction

January/February 2023

Table of Contents for the Digital Edition of January/February 2023