Furthermore, a steep increase in G by temperature increase was
noticed for JCF samples, which presented the highest G values as
well, followed by MF samples. A peak value of G is reached resulting
mainly from maximum swelling of starch granules. Furthermore
a plateau e.g. constant values may occur (see JFC sample,
Fig. 4a) due to irreversible swelling and solubilisation of amylose
(Ahmed et al., 2008) followed by a sudden drop of G under extensive
heating and shear and time. At this point a hot paste is created.
The height of the peak reflects the ability of the granules to swell
freely before their physical breakdown. A sudden drop after the
maximum indicates the breakdown on cooking as well as a great
ability to swell (Adebowale and Lawal, 2003). A shift of G curve
at higher temperatures i.e. a delayed response of FF under heating
is evident. It indicates a different behaviour compared to any other
flour fraction. The already mentioned values concerning a low SP,
high damaged starch amount and high soluble proteins amount
justify a weaker structure. It is a completely different sample that
has not a counterbalance between swelling and solubility in order
to increase elasticity. Retrogradation phenomena and gel forma-
tion were observed during cooling from 80 to 55 C in all samples
according to the increase in G values at this temperature range.