Evaluation of sodium lactate combined with chitosans of various molecular weights and Lac pigment for the extension of shelf-life and color development of low-fat sausages during refrigerated storage

The objective of this study was to investigate the color development and shelf-life effect of low-fat sausages (LFS) during refrigerated storage according to the additions of sodium lactate (SL), chitosan, and lac pigment. The LFS samples had 73 similar to 76% moisture, 3 similar to 4% fat, and 13 similar to 16% protein with a pH range of 6.4-6.6. The addition of chitosan (MW = 30 similar to 40 kDa) to LFS increased most textural properties. Hunter a (redness) values were increased by the addition of 0.05% lac pigment. The microbial growth of Listeria monocytogenes increased with increasing storage time. The addition of 2% SL and 0.3% chitosan with MW higher than 30-40 kDa effectively inhibited the growth of L monocytogenes. The microbial growth of L. monocytogenes was further reduced with increasing chitosan MW. These results indicated that the combination of SL with chitosans (MW > 30 kDa, 0.3%) and lac pigment (0.05%) improved shelf-life and color development in LFS during refrigerated storage.