Physical-chemical and rheological properties of pork batters as affected by replacing pork back-fat with pre-emulsified sesame oil were investigated. Replacement of pork back-fat with pre-emulsified sesame oil, improved L* value, moisture and protein content, hardness, cohesiveness, and chewiness, declined a* value, fat content and energy, but not affect cooking yield. When used pre-emulsified sesame oil to replace pork back-fat 50%, the sample had the highest L* value and texture. According to the results of dynamic rheological, replaced pork back-fat by pre-emulsified sesame oil increased the storage modulus (G') values at 80 °C, and formed firm gel. The result of Low-field nuclear magnetic resonance (LF-NMR) shown that the batters with pre-emulsified sesame oil had higher water holding capacity than the control. Overall, the batters with pre-emulsified sesame oil enabled lowering of fat and energy contents, making the pork batter had better texture.

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The effects of dynamic ultra-high pressure homogenization (UHPH) on the structure and functional properties of whey protein were investigated in this study. Whey protein solution of 10 mg/mL (1% w/w) was prepared and processed by a laboratory scale high pressure homogenizer with different pressures (25, 50, 100, 150, 200, and 250 MPa) at an initial temperature of 25 °C. Then, the solution samples were evaluated in terms of secondary structure, sulfhydryl and disulfide bond contents, surface hydrophobicity, average particle size, solubility, foaming capacity, emulsifying activity, and thermal properties. It was found that the secondary structure of whey protein changed with the dynamic UHPH treatment. The interchange reaction between the disulfide bond and the sulfhydryl group was promoted and the surface hydrophobicity significantly increased. The functional properties of the whey protein accordingly changed. Specifically, after dynamic UHPH treatment, the average particle size of the whey protein and emulsion decreased while the solubility, the foaming capability and the emulsification stability increased significantly. The results also revealed that with the dynamic UHPH at 150 MPa, the best improvement was observed in the whey protein functional properties. The whey protein solubility increased from 63.15 to 71.61% and the emulsification stability improved from 195 to 467 min.

The sodium chloride level and processing method significantly affected (p < 0.05) color, salt-soluble proteins (SSP) solubility, protein aggregation, texture and rheological properties. When increased sodium chloride, the L* value of raw batters, SSP solubility, protein aggregation, and formed firmer texture were increased (p < 0.05). At the same sodium chloride levels, the batters produced by beating process had higher L* value, SSP solubility, D3,2 value of SSP, and firmer texture than the chopping. Using the beating process, the cooked batters prepared with 1 % and 2 % sodium chloride had similar color, texture and the storage modulus (G’) value at 80 °C. The result of dynamic rheological exhibited that the temperature of protein denaturation was affected by sodium chloride contents and processing methods. In addition, the cooked batters formed uniform spongy-like structure when using the beating process. Overall, the use of beating process with 1 % sodium chloride is able to increase SSP solubility, protein aggregation, thus forming firmer gel texture.