ACTIVE PACKAGING FOR SHELF-LIFE EXTENSION OF BAKERY PRODUCTS

Abstract

In this study antimicrobial biodegradable film from poly (3hydroxybutyrate-co-4hydroxybutyrate), i.e. p(3HB-co-4HB) polymer was developed using thyme essential oil as an antimicrobial agent and analyzed as an active packaging material for shelf-life extension of bread. Solvent castingmethod was adopted for film development. Total bread fungus was targeted and in vitro antimicrobial efficiency of films found out choosing film having 30% (v/w) thyme oil and neat copolymer film as control. It was observed that 30% oil active films extended the shelf-life of bread between 5-10 days (mold growth was observed for control film after 5 days of storage but not for active film). Active films with 10%, 20%, 30% E.O. concentrations were studied for mechanical, thermal, chemical and morphological behaviors. Antimicrobial films yielded decreased tensile strength and modulus while increased % elongation at break. Also, glass transition and melting temperatures, % crystallinity reduced a little. WVTR of active films increased as compared to neat film. Color difference and variation in contact angles were not significant for antimicrobial films when compared to neat film. Fungal growth kept on increasing both for control and active film. On 19th day control plate exhibited mold count of approx. 10 log CFU/ml and 30% oil film had mold count of 9.4 log CFU/ml.