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Objective: To evaluate the effect of immersion frozen storage （IFS） on quality of the unwashed silver carp surimi. Methods: The surimi samples were immersed into liquid coolant non-contacted and stored at (-20±2) ℃ for 60 days, and changes in the Ca2+-ATPase activity, carbonyl content, thiobarbituric acid value （TBA）, as well as the strength, water holding capacity and structure of surimi gel during frozen storage were analyzed, using the traditional frozen storage （TFS） as a control. Results: The results were showed that surimi in IFS group passed through the maximum ice crystal formation zone in 10 min, which was much faster than that of surimi with TFS group （78 min）. The temperature fluctuation range during the whole storage period in IFS and TFS group was 0.72 ℃ and 1.43 ℃, respectively. With prolongation of frozen storage time, the Ca2+-ATPase activity, gel strength and water holding capacity of all samples gradually decreased, while protein carbonyl content and TBA value of all samples gradually increased, and the surimi gel network structure was gradually destroyed. However, changes of all the above indicators for IFS group were distinctly smaller than those for TFS group. Condusion: IFS could effectively alleviate the deterioration of surimi quality during storage, and was a potential low-temperature cold chain technique for food processing and preservation.

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.

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