It is believed that polyolefins, which include polyethylene and polypropylene, are
the best polymers for the production of packaging materials.
In 1933, English engineers E. Fosett and R. Gibson carried out polymerization of
ethylene at a temperature of 180-200 °C and a pressure of 140 MPa in the presence of
benzene peroxide, and obtained a “high-pressure polyethylene”. In 1954, K. Ziegler on
the system (С2Н5)3Аl + ТіСl4 received polyethylene at normal pressure and at room
temperature – the so-called low-pressure polyethylene. The properties of these
materials vary significantly. The latter is used in conditions of increased rigidity and
heat resistance, as well as low permeability.
Polypropylene is formed by pressing, injection molding, and extrusion. It can be
evaporated on metal, laid over paper, cardboard and fabric. Polypropylene films are
clearer and stronger than polyethylene ones, however they are less frost-resistant.
In recent years, in the food industry, a considerable attention has been paid to the
creation of fundamentally new non-toxic, easy-to-recycle, packaging materials capable
of providing food products with an effective protection against microbial damage and
the effect of air's oxygen, preventing them from drying in the process of production
and storage. More advanced way is to use a biaxial (duplex) oriented (that is, stretched
in perpendicular directions) polypropylene films (BOPP). Such packaging (film) has a
low density, high strength, rather low permeability, high transparency and gloss, and
low cost [2].
Most countries of the world ramp up the production of flour confectionery goods
and dry breakfasts intensively as well as expand their range fast. They are very popular
and are in demand among consumers. However, the stability of these products in
storage is relatively low. One of the components that is most affected by the negative
changes in the storage process is the fatty base of the products. During storage, the
major process is a lipid oxidation. Auto-oxidation goes even at low temperatures and
is stimulated by prooxidants. It is impossible to prevent oxidation, but it can be
decelerated by proper cleaning of fats from variable valence metals, addition of
antioxidants, ensuring optimal storage conditions and usage of modern packaging
materials.
A significant number of raw materials of plant origin contain compounds that
slow down the oxidation processes. The conducted researches confirm the antioxidant
activity of such raw plant materials as Aronia melanocarpa, Echinacea Purpurea,
Rhodiola rosea, hips, oregano, Thymus serpyllum, ginger, and their combinations with
synergists – ascorbic acid, lecithin and quercetin [3, 4].
Taking into consideration that staling is the main process that significantly
reduces the shelf life of gingerbreads, then due to changes in the dosage of main
components and addition of certain substances that reduce the activity of water
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