Affiliation: | 1. Department of Food Science and Biotechnology, Sungkyunkwan University, 2066 Seoburo, Jangangu, Suwon, 16419 Korea Queensbucket.co., Ltd, 64gil Taegaero, Seoul, Junggu, 04614 Korea Contribution: Funding acquisition (equal), Investigation (equal), Resources (lead);2. Department of Food Science and Biotechnology, Sungkyunkwan University, 2066 Seoburo, Jangangu, Suwon, 16419 Korea Contribution: Formal analysis (equal), Methodology (equal);3. Department of Food Science and Biotechnology, Sungkyunkwan University, 2066 Seoburo, Jangangu, Suwon, 16419 Korea Contribution: Formal analysis (equal);4. National Instrumentation Center for Environmental Management, Seoul National University, Seoul, 08826 Korea Contribution: Data curation (equal), Methodology (equal);5. Department of Food Science and Biotechnology, Sungkyunkwan University, 2066 Seoburo, Jangangu, Suwon, 16419 Korea |
Abstract: | Chemical profiles of aqueous or ethanolic extracts of 140, 170 and 200 °C-heated perilla meal were identified by GC-MS, and antioxidant properties of the extracts were observed via in vitro assays and in bulk oil or oil-in-water (O/W) emulsion. A total of 22 and 27 chemicals were found in aqueous and ethanolic extracts from non-heated samples, respectively. As the heating temperature increased to 200 °C, the carbohydrate and derivative contents decreased significantly (P < 0.05), whereas rosmarinic acid concentration decreased in both extracts. Ethanolic extracts possessed higher antioxidant activities than aqueous extracts based on the results of radical scavenging and ferric-reducing antioxidant power assays and the Rancimat assay, but there were no significant differences among samples (P > 0.05). In the case of O/W emulsions, aqueous extracts inhibited lipid oxidation more efficiently than ethanolic extracts at 50 °C. In particular, heat treatment decreased the antioxidant activities of ethanolic extracts and not aqueous extracts in the O/W emulsion system. Aqueous extracts are recommended in moisture-rich emulsion-based foods while ethanolic extracts are more suitable in a lipid-rich environment for enhancing oxidative stability. |