Effect of the whey protein isolate-pectin bilayer emulsion system on the textural properties and oil release characteristics of room-temperature stored processed cheese

Processed cheeses stored at room temperature exist some texture defects, such as texture softening and free oil release. The emulsion obtained by pre-emulsifying butter with whey protein isolate (WPI) can significantly improve the texture softening, but it was unable to mitigate the release of free oil during storage. Therefore, in this study, a WPI-pectin bilayer emulsion system was manufactured and applied in the production of processed cheese. The effects of adding the WPI-pectin bilayer emulsion system on the texture and functional characteristics of processed cheese during storage were investigated. The results of the study showed that the WPI-pectin bilayer emulsion system significantly improved the texture softening and free oil release characteristics of the room-temperature stored (RTS) processed cheese. Scanning electron microscopy revealed that the addition of the WPI-pectin bilayer emulsion system increased the uniformity of cheese microstructure and the number of small free fat pools after pre-emulsification. This study provided a method for improving the texture defects of RTS processed cheese, which is important for the processing and promotion of RTS processed cheese.