The Potential of Herbal Plant Extracts Native to South Minahasa as Traditional Coconut Oil Anti rancid Agents

Cooking oil is often quickly becoming rancid, changing its taste and smell. Rancidity in cooking oil occurs because of the oxidation process, fat oxidation in the diet can lead to negative impacts on human health. The aim of this research were to get the plant extracts, to identify its secondary metabolites composition and to examine the potential antirancid on coconut oil made traditionally by the Minahasan, a tribe in North Sulawesi, Indonesia. The research was carried out in three stages namely extraction of plants, analysis of secondary metabolite content, application extracts on coconut oil and coconut oil quality analysis. Parameters analysis of coconut oil quality were the number of the peroxide content, free fatty acids and antioxidant activity. The result showed that all plant extracts were composed by phytochemicals namely alkaloids, flavonoids, saponins, tannins, streroid and triterpenoid. The composition of steroid and triterpenoid was highly found in the seeds of Pangi (local name). Highly intensity alkaloids was found in Serei (local name) leaf extracts as well as in Pangi seeds while the the highest content of flavonoid was found in Pandan leaf extract. On the third day after the treatment, the average content of a lowest peroxide number on coconut oil provided by Pangi seed extract was 5 g in 40 ml of oil (b/v). While the highest number of peroxide content shown on the coconut oil given by Serei extract was 5 g in 40 ml of oil (b/v). Pangi seed extract possesed free fatty acids content lower than in extracts of Pandan leaf and Serei leaf by comparison. Pangi seed extract also showed a better antioxidant activity than Serei and Pandan leaf extracts. Keywords: serei leaf, pangi seed, pandan leaf, antioxidant, antiranci