Causal relations among starch chain-length distributions, short-term retrogradation and cooked rice texture. (November 2020)

• Record Type: Journal Article
• Authors: Li, Cheng; Luo, Ji-Xun; Zhang, Chang-Quan; Yu, Wen-Wen
• Is Part Of: Food hydrocolloids. Volume 108(2020)
• Publication Date: 2020-11
• Subjects: Cooked rice texture -- Starch chain-length distribution -- Mathematical fitting -- Short-term retrogradation -- Rapid visco-analyzer; CLD chain-length distribution -- SEC size-exclusion chromatography -- SBV setback viscosity -- HF hydrogel firmness -- DP degree of polymerization -- RDS rapidly digestible starch -- SDS slowly digestible starch -- RS resistant starch -- SCFA short-chain fatty acids -- AC amylose content -- RVA rapid visco-analyzer -- TPA textural profile analyzer -- SBE starch-branching enzyme -- SS starch synthase -- GBSS granule-bound starch synthase -- PCA principle component analysis; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2020.106064
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: Rice is cooked and consumed after a short-term cooling which is associated with the short-term starch retrogradation. The two most important textural attributes (hardness & stickiness) of 28 cooked rice varieties were investigated in this study, based on the causal relations between starch chain-length distributions (CLD) and short-term retrogradation properties. Size-exclusion chromatography (SEC) was used to characterize the starch CLD, while the setback viscosity (SBV) from rapid visco-analyzer and hydrogel firmness (HF) from textural profile analyzer were represented as characteristics of the short-term retrogradation process. Pearson correlations showed that regardless of amylose content, rice starches containing relatively shorter amylose molecules with short to long chains, and more amylopectin medium and long chains with the degree of polymerization (DP) > 69 can all promote the short-term retrogradation rate, resulting in cooked rice with a hard and non-sticky texture. It also suggests that both SBV and HF could be utilized to predict the final cooked rice texture such as the hardness and stickiness. Furthermore, rice starches with a relatively higher amount of medium chains but less short chains within the amylopectin molecules are related to a less sticky texture of the cooked rice. The current study provides important information for rice industry and breeding programs to develop new varieties with targeted eating qualities. Graphical abstract: Rice starches with a higher amylose content, relatively less amount of amylose swith hort and long chains, while relatively more amylopectin with medium and long chains have a faster short-term retrogradation rate, resulting in a harder but less sticky texture of cooked rice. Furthermore, rice starches with more amylopectin medium chains and relatively less amylopectin short chains could result in a less sticky texture of cooked rice. Image 1 Highlights: Cooked rice texture of 28 different rice varieties were investigated. Setback viscosity and hydrogel firmness can predict cooked rice texture. Starch short-term retrogradation determines cooked rice texture. Both amylopectin and amylose molecules are involved in short-term retrogradation. Starch chain length features controlling cooked rice texture are revealed.