Antioxidant activities of mandarin (<i>Citrus unshiu</i>) peel pectin films containing sage (<i>Salvia officinalis</i>) leaf extract
Hee‐Seon Han, Kyung Bin Song
Abstract
Summary Biopolymer films were prepared using pectin extracted from mandarin peel, a by‐product of fruit processing. Varying amounts (0.6%, 1.0% and 1.4%) of sage leaf extract (SLE) were also added to mandarin peel pectin (MPP) films to enhance its antioxidant abilities. Compared with the MPP film alone, the total phenolic contents of the MPP films containing SLE were higher. The MPP film with 0.6% SLE possessed the most desirable physical properties with tensile strength of 23.31 MPa and an elongation at break of 18.82%. We used four different methods to identify the antioxidant property of the MPP films with SLE, and the results showed that the antioxidant activity increased with increase in the amount of SLE added. In contrast, the addition of SLE lowered the thermal stability and water resistance of the MPP film. These results indicate that the developed MPP films containing SLE can be potentially used for food‐based applications.