Properties and Antioxidant Capacity of Anchovy (Engraulis Encrasicholus) By-Product Protein Films Containing Thyme Essential Oil

Abstract

In this study, some properties and antioxidant capacity of anchovy (Engraulis encrasicholus) by-product protein fi lms with added 0.5, 1.0 and 1.5 % of thyme essential oil were investigated. The fi lms with thyme essential oil had higher elongation at break, water vapour permeability and oxygen permeability, lower solubility and tensile strength than control fi lm (p<0.05). The incorporation of thyme essential oil aff ected transparency values of the fi lms, but only the addition of 1.5 % of thyme essential oil signifi cantly reduced the transparency (p<0.05). In the fi lm matrix, molecular organisation and intermolecular interaction were changed by thyme essential oil addition. The fi lms with thyme essential oil had a heterogeneous surface and a relatively smooth cross-section structure. Slightly higher phase transition and lower glass transition temperatures were observed in fi lms with thyme essential oil. The antioxidant capacity of the fi lms was improved by incorporating thyme essential oil depending on its volume fraction.