Water properties and structure of pork sausages as affected by high-pressure processing and addition of carrot fibre

The effects of high-pressure processing (HPP) and addition of carrot fibre on pork sausages have been studied using NMR T2 relaxometry and measurements of water-binding capacity (WBC) by centrifugation. Significant effects of temperature (raw, 40, 50, or 60°C), holding time (1s, 3, 6, or 9min), and addition of carrot fibre on the distribution and mobility of water were found. However, the effect of carrot fibre could not be explained by structural changes in the sausages when examined by confocal laser scanning microscopy (CLSM). Correlations between T2 relaxation measurements and WBC determined by centrifugation revealed that T2 relaxation times were able to explain more than 90% of the variation in WBC for both non-pressure and pressure-treated sausages. However, only 49% of the variation was explained for pressure-treated sausages with carrot fibre, indicating that combining addition of fibre and high pressure treatment causes non-coherent changes in T2 NMR relaxation times.