Resveratrol is a phenolic compound and has significant benefits for human health. Peanut, rich in resveratrol and with considerable biological activity, is generally considered as the raw material of functional food. Because of the low output of fresh peanut extracts, dried peanut powder often be used for extracting functional components. The effects of hot‐air drying (HD), infrared radiation drying (IRD), and microwave‐freeze‐drying (MFD) on the resveratrol extraction income and antioxidant activity of peanut were study. The most valid and economical method was IRD. The IRD peanut resveratrol extraction ratio was 33.5% and the DPPH free radical eliminate rate was 42.5%. The MFD peanut resveratrol extraction ratio was 40.9% and the DPPH free radical eliminate rate was 40.3%. However, the MFD energy consumption was the most. Practical Applications This study investigated the effects of different drying methods on the drying characteristics of peanuts and the extraction rate of the antioxidant active substance resveratrol. It was found that MFD could be used to obtain peanut powder with high resveratrol extraction rate and antioxidant activity, and IRD had excellent energy‐saving performance, and the relatively high extraction rate of the corresponding product is more favored by the industry. The results obtained in the current work would help the comprehensive utilization of peanut and provide new ideas for the food industry to extract natural compound.

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To improve the stability and solubility of Cornus officinalis flavonoid (COF), spray drying (SD), freeze‐drying (FD), and microwave freeze drying (MFD) were used to encapsulate COF using whey isolate protein (WPI) and gum arabic as wall materials. The characterization of COF microparticles was performed with encapsulation efficiency (EE), particle size, morphology, antioxidant activity, structure, thermal stability, color, stability during storage, and in vitro solubility. The results showed that COF was successfully encapsulated in the wall material with an EE between 78.86% and 91.11%. The freeze‐dried microparticles had the highest EE (91.11%) and the lowest particle size (12.42 ± 16.73 µm). However, the particle size of COF microparticles of SD and MFD was relatively large. The 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) scavenging capacity of the microparticles obtained from SD (89.36 mg Vc/g) was higher than that of MFD (85.67 mg Vc/g), but the drying time and energy consumption of microparticles dried by SD and MFD were lower than those of FD. Furthermore, the spray‐dried COF microparticles had higher stability compared to FD and MFD when stored at 4°C for 30 days. In addition, the dissolution of COF microparticles prepared by SD and MFD was 55.64% and 57.35%, respectively, in simulated intestinal fluids, which was lower than that of FD (64.47%). Therefore, the application of microencapsulation technology showed significant advantages in improving the stability and solubility of COF, and the SD can be used for the preparation of microparticles considering energy cost and quality. Practical Application COF is an important bioactive ingredient, but its poor stability and water solubility decreases its pharmacological value. COF microparticles can improve the stability of COF, enhance the slow‐release effect, and expand its application in the food field. The drying method will affect the properties of COF microparticles. Thus, the structures and properties analysis of COF microparticles by different drying methods can provide a reference basis for the preparation and application of COF microparticles.

The cross-linking degree between myosin affected the surimi gel properties in the hairtail. In this study, the effects of phlorotannin extracts (PE) derived from brown algae (Sargassum horneri) with different concentrations (0.05%, 0.3%, 1% w/w) on the hairtail surimi gel-forming properties were investigated in comparison with the commercial phloroglucinol (PG). The breaking forces of surimi gel with 1% PE and 0.05% PG were increased by 14.80% and 2.73%, respectively. The increase in deformation was 9.66% with 1% PE compared with the control added with water, but there was no increase in deformation of surimi gel with 0.05% PG. The improved surimi gel structure with PE as a bridge for the three-dimensional network forming of protein was observed in the microstructure. Moreover, PE could significantly shorten the water relaxation time (p < 0.05), reduce free water content (p < 0.05), and increase the hydrogen proton density of the hairtail surimi according to the results of NMR, dielectric properties, and MRI map, respectively. Our findings suggest that the extracts from the brown algae could be a potential economical gel structure enhancer to improve the myosin network.