Effects of pre-emulsification with whey protein and high temperature sterilisation on texture, functional characteristics and Maillard reaction products of room temperature stored processed cheese

The emulsion and emulsion gel obtained by pre-emulsifying butter with whey protein isolate (WPI) were applied in processed cheese making. The processed cheese was sterilised at 121 °C or pasteurised at 100 °C for 15 min, then stored at 25 °C or 4 °C. The effects of pre-emulsification and pasteurisation on texture, functional characteristics and Maillard reaction of processed cheese during storage were investigated. WPI emulsions significantly improved the texture and inhibited the free oil released from 25 °C stored cheese, while WPI emulsion gels softened the texture and increased the free oil released. Scanning electron microscopy revealed decreased uniformity of cheese microstructure and an increase in the number of large free fat pools after pre-emulsification. Pre-emulsification process slowed the Maillard reaction of refrigerated stored cheese and reduced the content of Maillard reaction products. This study provided a method for improving the texture defects of room temperature stored cheese.