Heterogeneous amylopectin delays short-term retrogradation via fabricating a binary gel network within steamed cold noodles

Abstract

This study aimed to investigate the influence of heterogeneous amylopectin (waxy corn starch, WCS) on the retrogradation of wheat starch (WS), hoping to provide a new idea for alleviating the retrogradation of steamed cold noodles. The chain length distribution data confirmed the formation of a binary gel network resulting from the heterogeneous amylopectin structure between WCS and WS. With the increase of WCS concentration, the modulus and setback value of WS-WCS binary gel decreased, which was attributed to the newly built network structure hindering the aggregation of WS molecules. Consistently, the results of water distribution and micromorphology showed that the addition of heterogeneous amylopectin improved the water-holding capacity of the system and made the network structure more dense. When the WCS content was added to 20 %, the retrogradation degree and B-type crystallinity of binary gel decreased from 13.83 % and 9.68 % to 6.17 % and 2.17 %. Besides, compared with pure WS, the hardness and stretching distance of steamed cold noodles of 20 %WCS respectively decreased and increased by 57.82 % and 20.80 % after 7 days of storage. In summary, WCS could effectively improve the storage stability of steamed cold noodles by forming a new network structure to inhibit the intermolecular rearrangement of wheat starch.