Antimicrobial, microscopic and spectroscopic properties of cellulose paper coated with chitosan sol-gel solution formulated by epsilon-poly-l-lysine and its application in active food packaging.

Cellulose paper-chitosan (CC) double-layer films containing epsilon-poly-l-lysine (ε-PL) (0.5 and 1% w/v) were developed. FTIR analysis showed a strong association between the ε-PL and CC film. Antimicrobial activity against Listeria monocytogenes was investigated both in vitro and in the chicken breast meat. The CC films without ε-PL showed no antimicrobial activity, while the addition of ε-PL induced significant (p < 0.05) effects. During the 28 days of storage at 4  ^° C, no significant difference was found on the anti-listeria activity of films. When storage temperature was raised from 4 to 22  ^° C, the antimicrobial activity was reduced. Films containing 1% ε-PL exhibited 1.5 log ₁₀  CFU/g reduction in L. monocytogenes population during 12 days storage of meat at 4  ^° C, while no significant reduction was found in CC films with 0.5% ε-PL (p > 0.05). This study revealed an antimicrobial activity for CC films impregnated with ε-PL, to control foodborne pathogens in meat.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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