10.3 GELATINIZATIONThis section dea

10.3 GELATINIZATION
This section deals with the phenomenon of gelatinization. This is a collective
term used to describe a range of irreversible events occurring when starch is
starch, water, and temperature result in gelatinization. A certain minimum level
of water content is necessary, and a certain temperature has to be reached. This
temperature depends on the starch. The word “gelatinization” seems to imply
that gel formation is involved; however, not all combinations of water content
and temperature that are found in the gelatinization area in Figure 10.2 will
result in the formation of a starch gel. The rheological changes during gelatinization are described in a following section. Gelatinization is often described
with, or related to, a gelatinization temperature. Different methods are used to
determine gelatinization temperatures; therefore, values found in the literature
differ considerably, even for the same starch. It is then natural to begin this
section with a description of what the gelatinization temperature is.
10.3.1 GELATINIZATIONTEMPERATURE
The gelatinization temperature is always a temperature range. For a single
starch granule in excess water, this temperature range might be 1 to 2°C,
whereas for the entire population the range might be 10 to 15°C [80,81]. To
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heated in water; however, as illustrated in Figure 10.2, not all combinations of