Slow Digestion Property of Native Cereal Starches

Abstract

The slow digestion property of native cereal starches, represented by normal maize starch, was investigated. The in vitro Englyst test showed that 53.0% of the maize starch is slowly digestible starch (SDS), and scanning electron microscopy (SEM) revealed that SDS starts from an increase of pore size until almost complete fragmentation of starch granules. However, similar amounts of SDS ( approximately 50%) were shown for partially digested fragmented starch residuals, which would normally be considered resistant to digestion based on the Englyst assay. Molecularly, both amylopectin (AP) and amylose (AM) contributed to the amount of SDS as evidenced by a similar ratio of AP to AM at different digestion times. Consistently, similar degrees of crystallinity, comparable gelatinization behavior, and similar debranched profiles of starch residuals following different digestion times indicated that the crystalline and amorphous regions of starch granules were evenly digested through a mechanism of side-by-side digestion of concentric layers of semicrystalline shells of native starch granules.

Effect of Resistant Starch as Dietary Fiber Substitute on Cookies Quality Evaluation

“…Nevertheless, Hylon V provided from HMT did not achieve quite high RS content. This phenomenon might suggest that the particle surfaces of Hylon V, unlike that of ordinary corn starch, were lack of some tiny holes and the interiors of the particles were without a large number of channels for amylase entering (Zhang et al, 2006). Hence, the disadvantage of the Hylon V caused some difficulties for amylase hydrolysis that occurred only on the surface of the starch granules not inside.…”

Structure of branching enzyme- and amylomaltase modified starch produced from well-defined amylose to amylopectin substrates

“…The reaction was terminated by boiling for 20 min. The hydrolysed samples containing α-limit dextrins were analysed for their apparent molar mass by HPSEC-RI (Zhang, Ao and Hamaker, 2006) using pullulans as standard (Polymer Laboratories Inc. Amherst, MA).…”

The impact of heat-moisture treatment on the molecular structure and physicochemical properties of normal and waxy potato starches

“…Susceptibility of starch to enzyme attack is influenced by several factors, such as granule size and available specific surface (Franco et al, 1992(Franco et al, , 1998Knutsonetal., 1982;Tahir etal., 2010;Tangetal.,2004),surfaceporosityandchannels (FaIllionetal., 1992(FaIllionetal., , 1993SujkaandJamroz, 2007;Zhang et al, 2006;), amylose and amylopectin content (Blazeck and COpelaIld, 2010;Hoover and Manuel, 1995;Hoover and Sosulski, 1985;Holm aIld Bjorck, 1988;Ring et al, 1988),crystallinestructure(Chungetal.,2010Zhouetal.,2004;Gunaratneand Hoover, 2002), extent of branching (long a.I11ylopectin branchesibraIlch density) (Dona eta1.,2010;Shresthaet al, 2010), distribution pattem ofa-(l,6) branch points between the amorphous aIld crystalline regions (Gunaratne and Hoover, 2002;Janeetal., 1997), degree of crystallinity (Chungetal., Zhou et al, 2004), packing of polymers within granules (dense/loose), helical conformation ofa.I11ylose molecules (Shrestha et al, 2010), presence of non-starch substances (proteins, lipids and phosphorus) (HooveraIld Manuel, 1995;Perera and Hoover, 1998) and inhibitors (Colonna et al, 1992;Zhou et al, 2004). The kinetics of a-amylolysis of granular and gelatinized starch are characterized by an initial rapid hydrolysis phase followed by a slower phase.…”

“…However, Zhang et al (2006) have shown in studies on cereal starches, that the amorphous and crystalline regions are digested simultaneously. A side-by-side and even digestion mechanism that starts from the channels was proposed as the mechanism leading to the simultaneous digestion of crystalline and amorphous regions.…”