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Background and Objective: Starch‐lipid complexes prepared by using partially gelatinized starch were more helpful in reducing the digestibility of starchy foods. Wet grinding (WG) could improve grinding homogeneity and avoid dust explosions. Moreover, as an excellent plasticizer, water could promote the movement of starch molecules during grinding. Therefore, this paper investigated the effect of WG on the structure and properties of corn starch with and without lauric acid. And the formation mechanism of starch‐lipid complexes under WG was explored. Findings: WG caused continuous hydration and even partial gelatinization of the starch. After 30 min of WG, the relative crystallinity, resistant starch (RS) content, and ΔH of the starch were all reduced to the minimum which were 25.82%, 21.55%, and 0.99 J/g, respectively. When lauric acid was added, WG promoted the formation of starch‐lipid complexes, and the RS content of starch reached the maximum (35.61%) after 30 min of WG. Conclusion: Appropriate WG could promote the formation of more starch‐lipid complexes with low swelling, low solubility, high thermal stability, and high antidigestibility. Significance and Novelty: This study provided a theoretical basis for future research on the preparation of high‐quality modified starch by WG. [ABSTRACT FROM AUTHOR]

BACKGROUND: Poor mechanical and water barrier properties of starch‐based films severely restrict their applications as packaging materials. In this study, glycerol was combined with various small molecular esters (SMEs) with different molecular structures to plasticize high‐content starch/poly(butylene adipate‐co‐terephthalate) (80/20, w/w) films (SPFs) prepared by extrusion blowing. The effects of co‐plasticization on the physicochemical properties and film‐forming mechanism of SPFs were investigated. RESULTS: The addition of glycerides to SPFs reduced intermolecular interaction, increased molecular chain mobility, and decreased glass transition, melting temperatures, and crystallinity. Mechanical and water barrier properties of SPFs were improved significantly with the co‐plasticization of glycerol and SMEs. The incorporation of triacetate glyceride increased tensile strength of SPFs by 54% and the water contact angle by up to 95°. The SPF with diacetate glyceride exhibited the minimum water vapor permeability, which decreased by 39%. CONCLUSION: The levels of hydrophilic/hydrophobic groups in SMEs and their molecular weights were essential for the plasticizing effects. Glycerides tended to infiltrate into starch for effective plasticization compared with citrates. The combination of glycerol and glycerides had better plasticizing effects on starch. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: At present, most studies have focused on the preparation of modified starches by dry grinding. As an excellent starch plasticizer, water might enhance the action of grinding on the structure of starch granules, and water grinding might improve the gel properties of starch. Therefore, this article explored the influence mechanism of water grinding on the gel properties of corn starch based on the changes in its structure and properties. RESULTS: The results showed that water grinding could make water enter the starch granules and hydrate the starch molecules, and the starch gelatinized after water grinding for 20 min. Thus, water enhanced the action of grinding on the structure of the starch granules. Under the plasticization and grinding action of water grinding, the mechanochemical effect of the starch granules occurred. When the starch was in the aggregation stage (7.5–10 min), the crystallinity of the starch increased, and the starch molecules rearranged into a more stable structure, which increased apparent viscosity (η), elastic modulus (G′) and viscous modulus (G″) of the starch gels. CONCLUSION: Therefore, appropriate water grinding (10 min) contributed to increasing the viscoelasticity of starch gels. This study provided a theoretical foundation for research on improving the properties of starch by mechanical modification in future. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Glycerol is a well‐known plasticizer for starch‐based materials, but it easily migrates during starch retrogradation, thereby deteriorating the films' properties. We hypothesized that the performance of high‐content starch/poly(butylene adipate‐co‐terephthalate) (PBAT) films could be enhanced by using sugar/sugar alcohol (glucose, sucrose and sorbitol) as natural, green and edible co‐plasticizers with glycerol.The employment of co‐plasticizers reduced the melt fluidity of the blends, established intermolecular hydrogen bonds with starch and resulted in a brittle film structure. The presence of sucrose contributed to the formation of more B‐type starch crystals. Glucose and sucrose promoted the conversion of bound water to entrapped water, while sorbitol contributed to more bound water. The co‐plasticizers enhanced films' thermal stability, moisture permeability (from 3.61 to 3.72 × 10−11 g m m−2 s−1 Pa−1), and oxygen barrier (from 12.84 to 8.74 × 10−13 cm3 cm cm−2 s−1 Pa−1). Glucose/glycerol co‐plasticized film had the maximum tensile strength (10.12 MPa), and sucrose/glycerol co‐plasticized film showed the highest Young's modulus (380.31 MPa).Sorbitol with linear structure and the lowest melting point exhibited a plasticizing capacity similar to glycerol. The molecular structure (linear or cyclic), hydroxyl group proportion and melting point of the sugar/sugar alcohol were the key factors to regulate the fine structure and properties of starch/PBAT films. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]