Properties of Oat Proteins Treated with Different Drying Methods and Effects on Gel Properties of Myofibrillar Protein

In order to study the effects of oat protein treated with different drying methods on meat product texture, four different drying methods (spray drying, freeze drying, vacuum drying and microwave drying) were used to treat oat protein, and their effects on the structure and properties of oat protein were investigated. Furthermore, the effects of addition of oat protein treated with different drying methods on the gel characteristics of myofibrillar protein were explored. The results showed that different drying methods had various effects on the structure and properties of oat protein, the free amino and carbonyl contents of oat proteins treated with freeze and microwave drying methods were significantly decreased compared with those of oat protein treated with spray drying method. The results of fourier transform infrared spectroscopy analysis showed that compared with oat protein treated with freeze, vacuum and microwave drying methods, no significant difference were observed in the content of α-helical and β-turned structure of oat protein treated with spray drying method, but the content of β-sheet structure decreased while the content of irregularly curled structure increased. The results of fluorescence spectroscopy showed that the maximum emission wavelengths of oat proteins treated with spray and vacuum drying methods were red-shifted compared with those of oat proteins treated with freeze and microwave drying methods. The surface hydrophobicity of oat protein treated with microwave drying method was the lowest while solubility was the best. Oat proteins treated with different drying methods had different influence on the gel properties of myofibrillar proteins. Compared with myofibrillar proteins, the gel temperature of oat proteins treated with freezing, vacuum and microwave drying methods had no change, while the gel temperature of spray dried oat proteins decreased by 2 ℃. The addition of oat proteins treated with microwave, vacuum and spray drying methods increased the gel G' and G", indicating increased elasticity and viscosity of the mixed gels, while the addition of oat proteins treated with freeze drying method reduced the viscosity and elasticity of the gels. The results of scanning electron microscopy showed that the gel network formed by mixing spray-dried oat protein and myofibrillar protein had a tighter mesh structure and relatively smaller pore size, while the gel network formed by freeze-dried oat protein and myofibrillar protein was looser and had relatively larger pore size. This study aims to provide certain technical parameters for the development of functional meat products, including grain-meat emulsion type meat products. © 2021, Editorial Department of Journal of Food Science and Technology. All right reserved.