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Starch and protein are two important components in food system. The interactions between starch and protein have important influence on the structure, physicochemical properties of starch and the texture and digestibility of starch-based food. In recent years, the effect of exogenous protein on starch-protein interaction in mixed system and its application have become a hot research topic in the field of food. This article reviews the interaction mode between starch and protein, the effect of protein on physicochemical properties （gelatinization properties, retrogradation properties, rheological properties, thermal properties and texture properties） and microstructure of starch-protein mixed system, summarizes the regulation effect of protein on digestibility of starch in mixed system and its mechanism, and presents the application of the mixed system in food processing, aiming to clarify the mechanism of interactions between starch and protein and provide theoretical reference for the research and development of starch-based food.

Objective: This study aimed to control the degree of crosslinking and etherification in the preparation process of crosslinked hydroxypropyl starch and improve the product performance. Methods: Waxy corn starch was used as a raw material to prepare the composite modified starch （hydroxypropyl distarch phosphate, HDP） under alkaline conditions, during which process sodium trimetaphosphate （STMP） and propylene oxide （PO） was used as the cross-linker and etherifying agent, respectively. The effects of the addition level of STMP and PO on the properties of the Brabender viscosity behavior, transparency and freeze-thaw stability of waxy corn starch were investigated. Results: Combined with the preliminary laboratory exploration and the optimization of this study, a HDP with improved thermal stability, transparency and freeze-thaw stability and lowered gelatinization temperature was obtained. The preparation conditions of HDP were as follows: in the case that the amount of sodium trimetaphosphate was 0.30 g/100 g and cross-linking reaction time was 45 minutes, and the amount of propylene oxide added was 6 mL/100 g and the etherification time was 90 minutes. Conclusion: Compared to raw waxy corn starch, the cross-linked and etherified starches with decreased gelatinization temperature and improved freeze-thaw stability, thermal stability and gelling properties are observed.

In this paper, two kinds of temperature control technology in grain storage including air conditioning and inner circulation were carried out in actual warehouse quality test of northeast japonica rice to analyzed the changes of grain condition, storage quality, cooking quality, texture quality and change of energy consumption. The results showed that both technologies can keep the warehouse temperature at 20 ℃～25 ℃and the surface grain temperature was within 23 ℃, but air conditioning for controlling temperature effect was more obvious, and the inner circulation grain storage had better water retention effect, the moisture content of surface japonica rice decreased by only 0.2%, and the operating cost was lower; During storage,the moisture content, taste score value, pH value of rice soup, viscosity and elasticity of rice all showed a decreasing trend in two warehouse, and fatty acid value, water absorption and expansion rate of rice, rice hardness, conglutination and chewing were on the rise, in the process of storage, both kinds of grain storage technology can effectively delay the quality deterioration of japonica rice, ensure the safety of northeast japonica rice for summer and achieve the green storage with good quality.

Polymeric materials, rich in carbon, hydrogen, and oxygen elements, present substantial fire hazards to both human life and property due to their intrinsic flammability. Overcoming this challenge in the absence of any flame-retardant elements is a daunting task. Herein, we introduce an innovative strategy employing catalytic polymer auto-pyrolysis before combustion to proactively release CO2, akin to possessing responsive CO2 fire extinguishing mechanisms. We demonstrate that potassium salts with strong nucleophilicity (such as potassium formate/malate) can transform conventional polyurethane foam into materials with fire safety through rearrangement. This transformation results in the rapid generation of a substantial volume of CO2, occurring before the onset of intense decomposition, effectively extinguishing fires. The inclusion of just 1.05 wt% potassium formate can significantly raise the limiting oxygen index of polyurethane foam to 26.5%, increase the time to ignition by 927%, and tremendously reduce smoke toxicity by 95%. The successful application of various potassium salts, combined with a comprehensive examination of the underlying mechanisms, underscores the viability of this strategy. This pioneering catalytic approach paves the way for the efficient and eco-friendly development of polymeric materials with fire safety. Overcoming this challenge of fire hazards by carbon, hydrogen, and oxygen rich materials remains challenging. Here, the authors demonstarte that catalytic polymer auto-pyrolysis before combustion releases CO2, equipping the material with fire retardant properties. [ABSTRACT FROM AUTHOR]