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Slowly Digestible Starch
For the purpose of definition starch can be quantified into different fractions by the
application of in vitro techniques. Depending upon the rate of starch digestion, the
starch can be classified as rapidly digestible starch (RDS) digested within 20 min,
slowly digestible starch (SDS) digested between 20 and 120 min corresponds to
SDS and the remaining fractions not further digested comprises resistant starch
(Mio et al. 2015). Most of processed starchy foods as such are a good source of
RDS, therefore rapidly digested by the small intestines leading to elevated glucose
levels and evident occurrence of hyperglycemia (Zhang et al. 2009). SDS as such
undergoes slow digestion from 20 to 120 min after being ingested providing for
slow and sustained glucose release throughout the time period. The digestibility of
SDS depends on a variety of factors most important being molecular structure
which includes amorphous phase packing, amylose/amylopectin ratio and crystallite structure that actually manipulates enzyme action (Colonna et al. 1992). The
practical value of SDS is negated while measuring initial glycemic responses since
under these assays only the glycemic response from 0 to 120 min are taken into
consideration sidelining the actual components of foods. Foods containing an
appropriate amount of SDS serve as an efficient source of functional components in
lowering blood glucose as it results in slow and prolonged release of glucose in
blood stream thereby helpful in controlling and preventing hyperglycemia related
diseases.
Nutraceutical Potential of Resistant Starch
Prebiotic Potential of Resistant Starch
Prebiotics are non-digestible carbohydrates that escape digestion in small intestine
and play a vital role in the survival of probiotics by providing fermentable carbohydrates to colonic bacteria (Coşkun 2006). Since resistant starch as such escapes
normal route of digestion from the small intestines but undergoes fermentation in
distal part of large intestines producing varied amounts of short chain fatty acids
(SCFA) mainly acetic acid, propionic acid and butyric acid (Yoa et al. 2009) thereby
increasing faecal bulk and lowering down colonic pH (Demigné and Remésy 1995).
RS seems to work as prebiotic by its ability to resist digestion in the small intestine
by possessing an inherent property to be dead set against enzymatic cleavage while
passing through the gastrointestinal tract that enables it to act as protective covering
for the bacteria in vivo (Wang et al. 1999). RS promotes a higher amount of butyric
acid in comparison to other non-digestible carbohydrates. Butyrate provides colonic
microbiota with a major energy substrate and plays a vital role in maintaining the
colonic health (Leeman et al. 2006; Scourboutakos 2010), by affecting cell metabolism, differentiation, cell growth and prevents the formation of colon tumors (Champ
Neutraceutical Properties of Resistant Starch
Slowly Digestible Starch
For the purpose of definition starch can be quantified into different fractions by the
application of in vitro techniques. Depending upon the rate of starch digestion, the
starch can be classified as rapidly digestible starch (RDS) digested within 20 min,
slowly digestible starch (SDS) digested between 20 and 120 min corresponds to
SDS and the remaining fractions not further digested comprises resistant starch
(Mio et al. 2015). Most of processed starchy foods as such are a good source of
RDS, therefore rapidly digested by the small intestines leading to elevated glucose
levels and evident occurrence of hyperglycemia (Zhang et al. 2009). SDS as such
undergoes slow digestion from 20 to 120 min after being ingested providing for
slow and sustained glucose release throughout the time period. The digestibility of
SDS depends on a variety of factors most important being molecular structure
which includes amorphous phase packing, amylose/amylopectin ratio and crystallite structure that actually manipulates enzyme action (Colonna et al. 1992). The
practical value of SDS is negated while measuring initial glycemic responses since
under these assays only the glycemic response from 0 to 120 min are taken into
consideration sidelining the actual components of foods. Foods containing an
appropriate amount of SDS serve as an efficient source of functional components in
lowering blood glucose as it results in slow and prolonged release of glucose in
blood stream thereby helpful in controlling and preventing hyperglycemia related
diseases.
Nutraceutical Potential of Resistant Starch
Prebiotic Potential of Resistant Starch
Prebiotics are non-digestible carbohydrates that escape digestion in small intestine
and play a vital role in the survival of probiotics by providing fermentable carbohydrates to colonic bacteria (Coşkun 2006). Since resistant starch as such escapes
normal route of digestion from the small intestines but undergoes fermentation in
distal part of large intestines producing varied amounts of short chain fatty acids
(SCFA) mainly acetic acid, propionic acid and butyric acid (Yoa et al. 2009) thereby
increasing faecal bulk and lowering down colonic pH (Demigné and Remésy 1995).
RS seems to work as prebiotic by its ability to resist digestion in the small intestine
by possessing an inherent property to be dead set against enzymatic cleavage while
passing through the gastrointestinal tract that enables it to act as protective covering
for the bacteria in vivo (Wang et al. 1999). RS promotes a higher amount of butyric
acid in comparison to other non-digestible carbohydrates. Butyrate provides colonic
microbiota with a major energy substrate and plays a vital role in maintaining the
colonic health (Leeman et al. 2006; Scourboutakos 2010), by affecting cell metabolism, differentiation, cell growth and prevents the formation of colon tumors (Champ
Neutraceutical Properties of Resistant Starch