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with the sugars, but less active than the amino acid, as contain less amino
groups.
Melanoidin - the main cause browning of foods during their manufacture,
storage and drying. Particularly this reaction takes place rapidly at elevated
temperatures during the technological process.
In the preparation of certain foods create special conditions for the reaction
of melanoidins. In some industries, this reaction is undesirable.
The oxidation process plays an important role in the storage of fats, oils and
fat-containing foods. Fats during prolonged storage becoming unpleasant taste
and smell - rancid, due to both chemical changes under the action of light and
oxygen from the air, and with the action of certain enzymes.
The simplest case is to rancidity products saponification of fat and the
emergence of a free form of butyric acid, which gives the product an unpleasant
smell.
Rancidity caused by oxidation of unsaturated fatty acids by atmospheric
oxygen, the most common type of rancidity. As a result, formed peroxides that
with further expansion to form aldehydes, imparting fat unpleasant taste and
smell.
In the absence of oxygen, this process does not go.
Regulation of structural-mechanical properties when machined. The
simplest method of studying the structure-mechanical properties of food
materials is to construct curves of deformation kinetics (flow curves). These
curves can be found seven independent from each other deformation
characteristics of the material: instantaneous modulus of elasticity and spring
back, the viscosity relaxation relaxation (flow) and spring back; limits of
elasticity and yield strength.
The value of the tensile strength is not invariant, as it depends on the
mechanical deformation mode. These constants allow to explain the deformation
behavior of the material and adequately characterize its structure-mechanical
properties.
The preparation of such characteristics is possible in the process of studying
the rheological properties of the food of the masses, that is, the study of the
process flow under constant stress.
Flow curves (rheogram) Newtonian fluids are a straight line passing
through the origin. All flow curves (dilatant fluids, structural - viscous liquid,
non-linear plastic body, linear plastic body), which deviate from a straight line,
called non-Newtonian fluids.
The curve - dilatant fluid, for characterizing dilatant characteristic mainly
for concentrated disperse systems in which with increasing strain rate comes
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