Packaging Methods for Minimally Processed Foods - Minimally Processed Foods - page 47

Commercial available moisture absorbing pads such as Cryovac ® Dri-Loc ®
(Sealed Air Corporation), MoistCatc™ (Kyodo Printing Co., Ltd.), and MeatGuard ®
(McAirlaid Inc.) are generally incorporated inside the high water barrier packages.
The new developments in moisture absorbing systems consist of multilayer packag-
ing materials that include an absorbing layer between the packaging layers. The use
of moisture regulating fi lms is approved by the FDA and EU food contact regula-
tions. Many companies are marketing moisture regulating fi lms under brand names
TenderPac ® , and Nor ® Absorbit. Nor ® Absorbit (Nordenia International AG) are
some additional examples of a moisture absorbing fl exible microwavable packaging
material. During microwave cooking, the Nor ® Absorbit fi lms are able to absorb
excess grease and water released by packed foods.

3.3.3.5 Ethylene Scavenging

Ethylene, a plant growth hormone, induces ripening in the climacteric fruits and
tells the shelf life of fresh plant produce. Once the fruits are ripe, ethylene may
cause increase in respiration rates leading to undesirable attributes such as textural
loss and colour changes. Therefore, ethylene scavenging is practiced for many years
to reduce the ripening of fruits before they are sent for retail markets. Among the
ethylene scavengers available in the market, potassium permanganate embedded in
silica is inexpensive the most commonly used ethylene scavenger. The silica absorbs
ethylene, and potassium permanganate oxidizes it to ethylene glycol. Silica is kept
in a sachet, highly permeable to ethylene, or it can be incorporated into the packag-
ing fi lm. There are also a number of ethylene scavengers using some form of acti-
vated carbon or zeolite with various metal catalysts. The direct surface contact
between the ethylene scavenger and the fruit should be avoided due the toxicity of
potassium permanganate. Activated carbon or zeolite with various metal catalysts
are also reportedly used as ethylene scavengers (Mexis and Kontominas 2014 ).
They are generally placed in paper bags or sachets inside the store rooms or for
retail purpose. Ethylene scavengers are quite effective in extending the storage of
packaged fruit, including kiwifruit, bananas, avocados, persimmons, and vegetables
like carrots, potatoes, and Brussels sprouts.

3.3.3.6 Ultraviolet Light Filters

The consumers' interest in transparent packaging, may often lead to the development
of off fl avours, degradation of omega fatty acids, PUFA's, carotenoids, vitamins, and
other nutrients. The above listed changes are initiated or accelerated by sunlight and
especially ultraviolet (UV) light, which causes degradation of specifi c food constitu-
ents via a photo catalytic auto degradation. It is therefore important to add a UV barrier
e.g. Nylon 6 of modifi ed crystallinity, in the transparent packaging fi lms of polyolefi n.
The incorporation of UV fi lters is very essential for retaining the colour of meat sau-
sages displayed in retail light cabinets, milk based products, fruit pastes, oils etc.