Two-step modification of pullulanase and transglucosidase: A novel way to improve the gel strength and reduce the digestibility of rice starch.

The multiscale structure, gel strength and digestibility of rice starch modified by the two-step modification of pullulanase (PUL) pretreatment and transglucosidase (TG) treatment for 6, 12, 18 and 24 h were investigated. The debranching hydrolysis of PUL produced some linear chains, which rearranged to form stable crystalline structures, reducing the digestible starch content, but weakening the gel strength. TG treatment connected some short chains to longer linear chains via α-1,6-glycosidic bonds, generating the structures of linear chain with fewer branches.

Structural, physicochemical and digestive properties of rice starch modified by preheating and pullulanase treatments.

The structural, physicochemical and digestive properties of rice starch modified by the combination of different temperature (60, 70, 80, 90 and 100 °C) preheating and pullulanase (PUL60, PUL70, PUL80, PUL90 and PUL100) treatments were investigated. The PUL60 treatment mainly modified the surface layer of starch granules, which increased the amylose content and damaged some ordered structures, resulting in slight decreases of gel strength and estimated glycemic index (eGI). With the increase of preheating temperature, PUL could act on more enzymatic sites to release a large amount of linear chains, reduce the ordered degree, and transform the A-type crystalline structure into B-type.

Understanding the texture and digestibility attributes of rice noodles supplemented with common vetch starch.

The effects of common vetch starch (CVS) substitution on rice noodle quality were investigated, aiming to improve their texture and reduce starch digestibility. The CVS had larger granule sizes, higher amylose content and more long branch chains compared with rice starch (RS). When the CVS substitution level was 20 %, the rice noodles had the best texture quality, as the mixtures with more total starch and amylose could form denser gel structures.

Effects of damaged starch on glutinous rice flour properties and sweet dumpling qualities.

This study focused on exploring the effects of damaged starch on glutinous rice flour properties and sweet dumpling qualities. Glutinous rice flours with different damaged starch contents (2-8%) and the same particle size were prepared through sifting and blending of semidry-milled and dry-milled rice flour. The increase of damaged starch content led to an increase in elastic modulus (G'), viscous modulus (G″) and agglomeration of starch granules, and a decrease in peak viscosity, breakdown value and enthalpy change (ΔH).

Dietary Proteins Alter Fermentation Characteristics of Human Gut Microbiota In Vitro.

The objective of this study was to evaluate the fermentation characteristics of proteins from diverse sources by human gut microbiota. Cereal proteins (rice and oat), red meat proteins (pork and beef), chicken protein and casein were selected as the substrates for simulated gastrointestinal digestion (SGID), and human faecal samples were collected from healthy donors as the inoculum of fermentation. In this study, we further analyzed the correlations of amino acids (AA) compositions, fermentation productions and gut microbiota.

Effects of Lactobacillus plantarum Inoculum on the Fermentation Rate and Rice Noodle Quality.

To accelerate the fermentation rate and reduce the adverse effects of undesirable microorganism contamination on rice noodle quality, the pure inoculum fermentation method was used to produce fermented rice noodles. The results indicated that the pure inoculum fermented rice slurry required 10 h to reach a stable pH value. While, the pH value of the natural, pure and natural inoculum fermented rice slurries required 54, 18 and 20 h to stabilize, respectively.

Effects of Lactobacillus combined with semidry flour milling on the quality and flavor of fermented rice noodles.

To shorten the fermentation time and reduce the contamination with heterozygous bacteria during the process of fermenting rice noodles, pure bacterial fermentation combined with semidry flour milling was used to produce fermented rice noodles. The changes in the pH value and microbial community diversity of the rice slurries, the physicochemical properties of the rice flours, and the texture, cooking qualities, sensory qualities and volatile components of the rice noodles prepared with different fermentative methods were investigated. The results showed that the pure bacterial fermentation required 18 h to reach a stable pH value, while the natural fermentation required 54 h.

Wheat Gluten Regulates Cholesterol Metabolism by Modulating Gut Microbiota in Hamsters with Hyperlipidemia.

The objective of this research was to evaluate the effect of wheat gluten on gut microbiota from hamsters and also analyse whether alterations in microbiota could result in wheat gluten's lipid-lowering properties. Four weeks male hamsters were divided into 3 groups (n=10). Two hypercholesterolemic groups were fed for 35 days with hypercholesterolemic diet, containing 20% (w/w) wheat gluten or casein.