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Objective： To explore the relationship between functional properties of rice glutelin fibril aggregates （RGFAs） solution formed by different storage and heating time. Methods: The RGFAs samples were prepared by heating rice glutelin （RG） at 85 ℃ and pH 2.0 for 2~15 h, and stored at 4 ℃ for 1 day and 4 days, respectively. The surface hydrophobicity, emulsifying property, shear viscosity of RGFAs samples as well as the gelatinization characteristics and hydrolysis rate of the mixture of RGFAs and starch were measured. Results: After storage at 4 ℃ for 4 days, the emulsifying properties were significantly improved. The surface hydrophobicity of RGFAs solution formed by heat treatment for 2~10 h decreased significantly （P＜0.05）, while the surface hydrophobicity of RGFAs solution formed after 15 h of heat treatment did not change significantly （P＞0.05）, and the shear viscosity of 15 h-RGFAs solution decreased. The gelatinization temperature of the mixture of starch and 2 h-RGFAs stored for 1 day was the lowest （83.98±0.08） ℃, and the hydrolysis rate of the mixture of starch and RGFAs samples stored for 1 day was lower than that of other samples. Conclusion: The inhibition of wheat starch hydrolysis by RGFAs samples stored for 1 day was better than that by RGFAs samples stored for 4 days.

Objective: The effect of dried silver carp process on quality and safety was studied. Methods: Taking the fresh silver carp as the raw material, the curing concentration (NaCl), curing temperature, curing time, drying temperature and drying time as investigating factors, investigated the effects of different processing conditions on the rehydration rate, color, texture and AGEs formation. Results: The concentration of curing salt and drying temperature had significant effects on the sensory evaluation of dried fish products (P＜0.05), and the optimal processing conditions obtained were curing concentration of 9%, curing temperature of 4 ℃, curing time of 3 h, drying temperature of 60 ℃ and drying time of 24 h. The alkanes, aromatic compounds and sulfur-containing organic compounds contributed most to the flavor of dried fish. The dried fish products with a curing concentration of 9%, curing temperature of 4 ℃, curing time of 3 h, and drying temperature of 60 ℃ had better retention of flavor substances. The samples became yellowish in color, less bright and harder, which was reflected in sensory changes as dried fish products with golden color, firm texture and non-flabby tissue. The content of carboxymethyl lysine (CML) and carboxyethyl lysine (CEL) increased with increasing salt content. However, the differences in CML and CEL of dried fish under 3% and 9% salt concentration curing were not significant. Conclusion: The dried fish products with curing concentration of 9%, curing temperature of 4 ℃, curing time of 3 h, drying temperature of 60 ℃ and drying time of 24 h are the optimal products. This study provides technical support for the processing and safety control of dried silver carp.

Objective: Improvement of the baking quality of the multi-grain pre-blent bread flour. Methods: On the basis of the previous study on the preparation of low glycemic index multi-grain pre-blent bread flour with oat flour, chickpea flour and wheat flour as the main raw materials, this study employed single factor experiment and response surface methodology to optimize the formula of the pre-blent bread flour. Results: The optimal concentration of xanthan gum, gluten, maltose amylase and ascorbic acid were 0.78 g/100 g, 3.42 g/100 g, 200.00 mg/kg and 171.70 mg/kg, respectively. The specific volume and hardness of the prepared bread were （2.21±0.03） mL/g and （15.97±0.69） N, respectively, which were closed to the bread made with pure wheat flour. The sensory evaluation results （including odor, internal structure, taste and overall acceptability） of the bread prepared from the multi-grain pre-blend flour were better than that of bread made from pure wheat flour. Conclusion: The formula of multi-grain pre-blent bread flour optimized by this study can be used in industrialization.

This study uses Polyacrylamide gel electrophoresis (SDS-PAGE) and acid polyacrylamide gel electrophoresis (A-PAGE) to identify the composition of high molecular weight glutenin subunits (HMW-GS)and the translocation of gliadin 1BL/1RS in two high quality wheat flour. The gliadin and glutenin are separated and extracted from wheat flour by separating and recombining, then re-proportionated with proportions. The cooking quality and texture of reconstituted noodles are analyzed to identify the relationship between gliadin, glutenin and noodle’s quality. The results show that when the protein content is constant, the water absorption of recombinant noodles is negatively correlated with (gluten: alcohol) (P＜0.05), while the dry matter loss rate is not highly relevant to gluten: alcohol. The hardness, firmness and tensile strength of recombinant noodles are positively correlated with gluten: alcohol (P＜0.05). The viscosity is negatively correlated with gluten: alcohol (P＜0.05). Meanwhile, it is found that when the properties of high molecular weight glutenin and gliadin are the same, only the composition of low molecular weight glutenin is different from the precipitation value, but the properties of reconstituted noodles are similar. Therefore, we conclude that high molecular weight glutenin has a greater impact on the quality of noodles.

This study developed a novel photocatalytic method to synthesize pyranones from furfural alcohols. By using 0.2 mol% equivalent of tris-Ir(ppy)3 as a photocatalyst under visible light and O2 as the reaction atmosphere, furfural alcohols were rapidly oxidized and hydrolyzed in the aqueous reaction solution to produce diol intermediates, which further underwent hydrolysis, furan ring-opening and rearrangement to form the final product pyranones. The entire reaction was carried out at room temperature with a yield as high as 86% and a conversion efficiency of 90%. This method is general and suitable for furfural alcohols with different substituted groups on the 5- and α-OH sites. We used in situ IR and real-time NMR to examine the reaction kinetics, GC-MS and isotope-labeling experiments to track the source of atom transfer in the reaction, and EPR to identify the singlet oxygen. The results showed that the reaction followed a first-order rate equation, and O2 oxidation was the rate-determining step. The transferred H atom came from the H2O solvent, the O atom from the O2 atmosphere, and the singlet oxygen from the O2 photocatalysis. The UV-vis and cyclic voltammetry results indicated that this photocatalysis reaction involved a single electron transformation process. We also used DFT calculation to simulate the reaction routes and showed that the tris-Ir(ppy)3 photocatalysis O2 oxidation in the aqueous phase was the critical step of endoperoxide oxidation, which differs from oxygen onium ion oxidation in the classic Achmatowicz rearrangement reaction. Our method can carry out a 10.0 gram-scale reaction with a 78% yield. It avoids stoichiometric consumption of toxic or corrosive oxidative reagents in the Achmatowicz rearrangement reaction. It may provide a novel, efficient, and "green" alternative to the Achmatowicz rearrangement reaction. [ABSTRACT FROM AUTHOR]

The inhibitive action of anionic surfactant of sodium lignosulfonate (sLs) on 1060 industrial pure aluminum in hydrochloric acid media was studied by weight loss, potential dynamic polarization curves, electrochemical impedance spectroscopy ( Eis ), scanning electron microscope ( sEM ) and atomic force microscope ( AFM ) . These results show that sLs exhibits a significant inhibitory effect on the corrosion of aluminum,and the inhibition efficiency increases with the increase of sLs concentration. At 25 °C, the maximum inhibition efficiency of 1. 0 g/L sLs can reach as high as 83. 0% . The inhibition is dropped to more extent with the increase of temperature. The adsorption behavior of sLs on aluminum surface follows Langmuir adsorption isotherm, and the absolute value of the standard adsorption Gibbs free energy ( AGads) is in the range of 20 -28 kj/mol,which indicates that the adsorption type of sLs on aluminum surface involves the mixed adsorption comprising physical and chemical effects at the same time. The po-tentiodynamic polarization curves show that sLs is a cathodic inhibitor that mainly suppresses the cathode. Nyquist diagram shows dispersive capacitive reactance arc at the high frequency region and inductive arc in the low frequency region. The charge transfer resistance of aluminum increases after adding a small amount of sLs. There are two time constants that control the electrochemical corrosion process. sEM and AFM showed that sLs efficiently retarded the corrosion of aluminum surface in HCl solution,and the root mean square roughness (Rq) was reduced by 277 nm. [ABSTRACT FROM AUTHOR]