19
© Springer Nature Switzerland AG 2021
A. Gani, B. A. Ashwar (eds.), Food biopolymers: Structural, functional
and nutraceutical properties, https://doi.org/10.1007/978-3-030-27061-2_2
Resistant Starch and Slowly Digestible
Starch
Bilal Ahmad Ashwar, Adil Gani, Asima Shah, Mudasir Ahmad, Asir Gani,
Faiza Jhan, and Nairah Noor
Introduction
In human nutrition, starch plays an important role in supplying metabolic energy,
which enables the body to perform its functions. Based on the rate and extent of
digestion, starch has been classified into different fractions viz. Rapidly Digestible
Starch (RDS), Slowly Digestible Starch (SDS), and Resistant Starch (RS) (Englyst
et al. 1992). Starch has been quantified into these fractions using the in vitro Englyst
assay: the starch fraction digested within 20 min of incubation has been classified as
RDS, the starch fraction digested between 20 and 120 min corresponds to SDS, and
the remaining fraction that was not further digested has been classified as RS. RDS
induces a rapid increase in the blood glucose and insulin levels, which may cause a
series of health complications, such as diabetes and cardiovascular diseases (CVD).
SDS is slowly digested in the small intestine, thereby resulting in a slow and prolonged release of glucose into the blood, coupled to the low glycemic response.
Thus SDS can be helpful in controlling and preventing hyperglycemia-related diseases. Resistant Starch (RS) is the fraction of starch that is resistant to hydrolysis by
α-amylase and pullulanase enzymes in vitro and may be fermented in the colon
(Englyst et al. 1982). It is that fraction of starch, which escapes digestion in the GI
tract but may be fermented in the colon (Englyst et al. 1996). The end-products of
fermentation are carbon dioxide, hydrogen, methane and short chain fatty acids
(SCFAs).
RS is measured as the difference between total starch (TS) and the sum of rapidly
digestible starch (RDS) and slowly digestible starch (SDS) (Sajilata et al. 2006).
RS TS RDS SDS
=
−
+
(
)
B. A. Ashwar · A. Gani (*) · A. Shah · M. Ahmad · A. Gani · F. Jhan · N. Noor
Department of Food Science and Technology, University of Kashmir, Srinagar, India
© Springer Nature Switzerland AG 2021
A. Gani, B. A. Ashwar (eds.), Food biopolymers: Structural, functional
and nutraceutical properties, https://doi.org/10.1007/978-3-030-27061-2_2
Resistant Starch and Slowly Digestible
Starch
Bilal Ahmad Ashwar, Adil Gani, Asima Shah, Mudasir Ahmad, Asir Gani,
Faiza Jhan, and Nairah Noor
Introduction
In human nutrition, starch plays an important role in supplying metabolic energy,
which enables the body to perform its functions. Based on the rate and extent of
digestion, starch has been classified into different fractions viz. Rapidly Digestible
Starch (RDS), Slowly Digestible Starch (SDS), and Resistant Starch (RS) (Englyst
et al. 1992). Starch has been quantified into these fractions using the in vitro Englyst
assay: the starch fraction digested within 20 min of incubation has been classified as
RDS, the starch fraction digested between 20 and 120 min corresponds to SDS, and
the remaining fraction that was not further digested has been classified as RS. RDS
induces a rapid increase in the blood glucose and insulin levels, which may cause a
series of health complications, such as diabetes and cardiovascular diseases (CVD).
SDS is slowly digested in the small intestine, thereby resulting in a slow and prolonged release of glucose into the blood, coupled to the low glycemic response.
Thus SDS can be helpful in controlling and preventing hyperglycemia-related diseases. Resistant Starch (RS) is the fraction of starch that is resistant to hydrolysis by
α-amylase and pullulanase enzymes in vitro and may be fermented in the colon
(Englyst et al. 1982). It is that fraction of starch, which escapes digestion in the GI
tract but may be fermented in the colon (Englyst et al. 1996). The end-products of
fermentation are carbon dioxide, hydrogen, methane and short chain fatty acids
(SCFAs).
RS is measured as the difference between total starch (TS) and the sum of rapidly
digestible starch (RDS) and slowly digestible starch (SDS) (Sajilata et al. 2006).
RS TS RDS SDS
=
−
+
(
)
B. A. Ashwar · A. Gani (*) · A. Shah · M. Ahmad · A. Gani · F. Jhan · N. Noor
Department of Food Science and Technology, University of Kashmir, Srinagar, India