Phosphate replacing potential of apple pomace and coffee silver skin in Irish breakfast sausage using a mixture design approach

The ability of apple pomace (AP) and coffee silver skin (CSS) powders to replace the techno-functional properties of synthetic phosphates used in Irish breakfast sausages was evaluated using a specialised response surface-mixture design approach. Sausages of 18 different formulations of sodium tripolyphosphate (STPP), AP and CSS mixtures were made and the results of water holding capacity (WHC), cook loss, colour, textural properties, low-field nuclear magnetic resonance (NMR), compositional analysis and lipid oxidation values were analysed. Addition of ingredients to the sausage formulations significantly improved the WHC (P < 0.001) and decreased the cook loss (P < 0.001) of the products. Interestingly, addition of AP and CSS decreased the hardness (P < 0.001), chewiness (P < 0.001), gumminess (P < 0.004) and springiness (P < 0.001). TBARS analysis showed that the addition of ingredients AP and CSS decreased the MDA content on day 9 (P < 0.018). Analysing these obtained results, the software has predicted three optimised sausage formulations based on the desirability response method. These formulations help in reducing the phosphate level in sausages with accepted desirability, thereby maintaining the overall quality of the product.