As a result of technological processing, RS II present in
a variety of products (e.g. raw potato starch) is subject to gelatinisation
and loses its resistance to the activity of enzymes.
The exception is high-amylose maize starch whose granules
are only partly gelatinised at usual temperature of most of
technological processes (ca. 100°C). An exceptionally high
degree of resistance to amylolytic enzymes is displayed by
starch of ae-VII hybrid of that maize [Haralampu, 2000]. It
contains ca. 70% of amylose and 12%–18% of resistant
starch [Thompson, 2000]. In this starch, RS concentration
may be increased by thermal treatments, including annealing
in water at a temperature lower than that of gelatinisation,
heat-moisture or induction of swelling without causing damage
to the granule structure. Such treatments evoke an
increase in RS content up to 30%–40% [Würsch, 1999].