Effect of aqueous extract, hydrosol, and essential oil forms of some endemic Origanum L. (Lamiaceae) taxa on polyphenol oxidase activity in fresh‐cut mushroom samples

Abstract

Origanum L. is one of the high-value medicinal and aromatic plants generally used for various purposes in the field of food and health. This study evaluated the effect of aqueous extract, hydrosol and essential oil forms of seven Origanum taxa including three endemic species in fresh-cut mushroom samples in order to prevent polyphenol oxidase (PPO) activity. Food samples were treated with these natural preservatives (aqueous extract, hydrosol, and essantial oil) and stored at 4°C temperature for a maximum of 5 days. It was found that the extract form of Origanum vulgare L. subsp. hirtum (Link) Ietsw. provided maximum PPO inhibition with 64.50% of reduction on 3rd day. Similarly, 3-fold reduction in hydrosol application was observed with Origanum bilgeri P. H. Davis which is the endemic plant. These results were conducted with the extract forms containing water are more effective than essential oil form to inhibit PPO activity. Practical applications In this study, we have investigated alternative usage of some Origanum plants as natural anti-browning food additives in mushroom samples. The samples separately treated with aqueous extract, hydrosol, and essential oil forms of different Origanum plants were stored until 5 days. PPO activities of samples on 1st, 3rd, and 5th days were used to determinate the shelf life of mushrooms associating with their browness.