Abstract: The present study investigated the effect of high pressure processing (HPP) (0.1, 100, 200, 300 MPa) on the water-holding capacity, water distribution and microstructure of low-fat emulsion sausages by low-field nuclear magnetic resonance and scanning electron microscopy. The results revealed that compared with the control group, HPP at increasing pressure from 100 to 300 MPa significantly increased the proportion of bound water and immobilized water and reduced the proportion of free water (P < 0.05). The treatment at 200 MPa gave the best water state distribution. In addition, HPP significantly changed the microstructure of emulsion sausages and increased the size and number of cavities in the gel structure. Furthermore, a significant positive correlation was observed between water-holding capacity, water state and microstructure through principal component analysis. In conclusion, HPP can improve the microstructure, reduce the proportion of free water, and improved the water-holding capacity of low-fat emulsion sausages.

Key words: emulsion sausages, high pressure processing, low-field nuclear magnetic resonance, T2 relaxation time, microstructure