Antioxidative Activity of Crackers Made with a Guava(Psidium guajava Linn.) Leaf Extract Harvested in Korea

The objectives of this study were to investigate the antioxidative activity of crackers made with a guava(Psidium guajava Linn.) leaf extract harvested in Korea. Guava leaf extraction using boiling water showed significantly higher antioxidative activities than extracting using 70% ethanol based on the higher total phenolic contents, FRAP, and ABTS assays(p<0.05). The crackers containing 1% guava leaf extract, and 0.075% BHT were stored at $63^{\circ}C$ for 7 days for the Schaal oven test, and the oxidative stability(AV, POV), antioxidative activity(DPPH, FRAP, ABTS assay), and sensory evaluation were compared. The crackers containing 1% guava leaf extract were found to have a higher oxidative stability than the control due to a lower acid value and peroxide value after 7 days of storage. The antioxidative activities of the crackers containing 1% guava leaf extract was the highest after 7 days as determined in the DPPH and ABTS assay, and was lower than crackers containing 0.075% BHT after 4 days as assessed by the FRAP assay. In the sensory evaluation, the crackers containing the 1% guava leaf extract had the highest scores in terms of taste, texture, and overall palatability than others at increasing storage time. As a result, the addition of 1% guava leaf extract harvested in Korea increased the antioxidative effect as well as the sensory acceptability of crackers.

한국산 구아바 잎 추출물을 첨가한 크래커의 항산화활성