Preparation of Antimicrobial Collagen Casings with High Mechanical Properties

Tea Polyphenols (TP) has received much attention for their excellent antioxidant and antibacterial activities. Some additives (such as sodium alginate and sodium pyrophosphate) have good hydrophobicity which have influence on the mechanical properties of food. The effect of TP on the antibacterial activity of collagen casing was investigated, the effect of addition of TP, sodium pyrophosphate and sodium alginate on mechanical properties including tensile force, tensile strength and elongation at break were also studied. Results from the single factor experiments demonstrated that TP showed strong antibacterial activities against Escherichia coli, Staphylococcus aureus and Salmonella according to the Minimum Inhibitory Concentration (MIC) and the inhibition zone method. Moreover, the mechanical properties of collagen casings were obviously influenced by the addition of TP and two food additives including sodium alginate and sodium pyrophosphate. This work would be useful for application of collagen casings with TP in food package to extend shelf-life of sausage during processing, transportation and storage.