TY - JOUR

T1 - Ethanol pretreatment increases the efficiency of maltogenic α-amylase and branching enzyme to modify the structure of granular native maize starch

AU - Zhong, Yuyue

AU - Herburger, Klaus

AU - Xu, Jinchuan

AU - Kirkensgaard, Jacob Judas Kain

AU - Khakimov, Bekzod

AU - Hansen, Aleksander Riise

AU - Blennow, Andreas

N1 - Publisher Copyright: © 2021

PY - 2022

Y1 - 2022

N2 - A method for efficient functional modification of starch granules by thermal ethanol pre-treatment and subsequent maltogenic α-amylase (MA) and branching enzyme (BE) post-treatments is described. Ethanol pre-treatment significantly increased the swelling power of starch granules thereby increasing the MA and BE susceptibility. Ethanol pre-treated granules became shrunk and twisted after incubating in buffer. Sequential MA post-treatments remarkably increased the α-1,6 to α-1,4 ratio and the content of amylopectin short chains (DP 1–10), contributing to the low retrogradation rate. BE post-treatments significantly decreased the product yield, increased the relative crystallinity of starch granules, suggesting BE had intramolecular transglucosylation activity which altered the branch position and reduced the molecular size by forming cyclic structures. Moreover, BE post-treatments showed an α-1,6 to α-1,4 transglucosylation activity by decreasing the α-1,6 to α-1,4 ratio, especially during simultaneous MA and BE catalysis. However, in the simultaneous MA and BE post-catalysis, MA dosage was predominant by noticeably hydrolyzing amylopectin and amylose molecules and increasing the α-1,6 to α-1,4 ratio, thereby leading to the lowest digestibility and retrogradation.

AB - A method for efficient functional modification of starch granules by thermal ethanol pre-treatment and subsequent maltogenic α-amylase (MA) and branching enzyme (BE) post-treatments is described. Ethanol pre-treatment significantly increased the swelling power of starch granules thereby increasing the MA and BE susceptibility. Ethanol pre-treated granules became shrunk and twisted after incubating in buffer. Sequential MA post-treatments remarkably increased the α-1,6 to α-1,4 ratio and the content of amylopectin short chains (DP 1–10), contributing to the low retrogradation rate. BE post-treatments significantly decreased the product yield, increased the relative crystallinity of starch granules, suggesting BE had intramolecular transglucosylation activity which altered the branch position and reduced the molecular size by forming cyclic structures. Moreover, BE post-treatments showed an α-1,6 to α-1,4 transglucosylation activity by decreasing the α-1,6 to α-1,4 ratio, especially during simultaneous MA and BE catalysis. However, in the simultaneous MA and BE post-catalysis, MA dosage was predominant by noticeably hydrolyzing amylopectin and amylose molecules and increasing the α-1,6 to α-1,4 ratio, thereby leading to the lowest digestibility and retrogradation.

KW - Branching enzyme

KW - Cold swelling starch

KW - Maltogenic α-amylase

KW - Solid state modification

KW - Starch

U2 - 10.1016/j.foodhyd.2021.107118

DO - 10.1016/j.foodhyd.2021.107118

M3 - Journal article

AN - SCOPUS:85113365487

VL - 123

JO - Food Hydrocolloids

JF - Food Hydrocolloids

SN - 0268-005X

M1 - 107118

ER -