THESIS

1.2.3 Resistant starch and metabolic responses
Resistant starch is not absorbed and therefore causes minimal
increase in post-prandial glucose potential (hence has low glycemic index, GI), and
insulin. This is the case with most legume starches which have higher amylose
content than cereal starches and are easily retrograded to produce higher levels of
resistant starch (Crosby, 2003). Legumes and other complex carbohydrate-based
foods constitute a large part of the diet in many non-Western societies, and the
protective role of resistant starch may be more obvious. This is significant in the
management and control of glucose-metabolism related diseases such as type II
diabetes and obesity.
1.2.4 Resistant starch and insulin and glucose metabolism
Insulin is a hormone that enables glucose uptake by muscle and
adipose cells, thereby lowering blood glucose levels (Bornet et al. 1989). It also
inhibits the use of stored body fat and together with an array of other physiological
signals can modulate appetite and satiety signals. RS-rich foods release glucose
slowly and therefore one would expect this to result in a lowered insulin response,
greater access and used of stored fat and potential, a muted generation of hunger
signals. Not only would these conditions help in the management of clinical
conditions, such as diabetes and impaired glucose tolerance, but also possibly in the
treatment of obesity and in weight management (Goddard et al. 1984).
1.2.5 Resistant starch and lipid metabolism
Cheng and Lai (2000) investigated the effects of different proportion
of rice starch and cornstarch on lipid metabolism in rats fed high dietary cholesterol.
They found that the rice starch was aggregation (n= 20 - 60) of smaller granules (3 - 8
micron in diameter), whereas the cornstarch was composed of larger (5 - 15 micron),
single granules. The compound rice starch (0.99 kg/L) was larger in size and denser in
structure than cornstarch (0.63 kg/L). Serum total cholesterol concentrations in rats
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