Optimization of Gotu Kola Frying Temperature and Time based Secondary Metabolites and Antioxidant Activity using TOPSIS Analysis

¹ Department of Agricultural & Biosystems Engineering, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
² Research Center for Pharmaceutical Ingredients and Traditional Medicine, Research Organization for Health, National Research and Innovation Agency Republic of Indonesia, Jl. Raya Jakarta-Bogor KM 46, Cibinong, Bogor, West Java, Indonesia

^* Corresponding author: deviyunisusanti@ugm.ac.id

Abstract

Fried vegetables are appreciated for their savory flavor and crunchy texture. Gotu kola can also be consumed fried, but frying temperature and time impact its nutrients and antioxidant properties. This study aims to identify the optimal frying method to preserve the beneficial qualities of gotu kola. In this study, gotu kola frying process was conducted with three temperature variations (130°C, 145°C, 160°C) and six frying durations, namely (1, 3, 5, 7, 9 and 11 minutes). The samples were then tested for secondary metabolite content including total flavonoid content (TFC), total phenol content (TPC), and asiaticoside content (AC). The data were analyzed using DMRT to assess the impact of temperature and boiling duration on secondary metabolite content. Based on asiaticoside content, the three best methods were selected as alternatives for further study. These methods were then evaluated for antioxidant activity using DPPH and Nitric Oxide scavenging assays, followed by analysis with the TOPSIS method. The study found that frying gotu kola at 160 ºC for 1 minute preserves its secondary metabolites and antioxidant activity, suggesting that medium-temperature, short-duration frying helps retain its health benefits.