Effects of various additives on antioxidant and antimicrobial effectiveness in emulsion-type sausages
We investigated the effects of rosemary extract (RE), α-tocopherol (AT) and chitosan (CH) added individually or in combination as compared with butylated hydroxyanisole (BHA) on microbiological parameters [total viable count (TVC), lactic acid bacteria (LAB), enterobacteria (ENB), pseudomonas bacteria (PSY)], pH and lipid oxidation of emulsion-type sausages stored for 28 days at 4°C. TVC, LAB, ENB, and PSY counts were significantly increased (P<0.05) in all treatments throughout the refrigerated storage. CH and its combination with either RE or AT, or BHA alone, had the minor antimicrobial effectiveness compared to individual use of RE or AT (P<0.05). However, there were no differences (P>0.05) in all microbial counts between AT and control groups during the whole storage period. Overall storage had a significant effect on lowering pH, but no influence of additives on pH values was detected, except for 2and 28 days of storage. During refrigerated storage, CH and its combination, or BHA in emulsion-type sausages was more effective in delaying lipid oxidation compared to RE and AT (P<0.05). In conclusion, this study showed the minimal antioxidant and antimicrobial effects of using CH and its combination or BHA alone in emulsion-type sausages rather than single antioxidant.
Key words: Rosemary extract, α-tocopherol, chitosan, butylated hydroxyanisole (BHA), antioxidative effect, antimicrobial effect.