A Study on the Effectiveness of Various Concentrations of Clove Flower Extract (Syzygium aromaticum) in Reducing the Peroxide Value of Used Cooking Oil

The repeated use of cooking oil in the frying process can accelerate lipid oxidation and reduce the quality of the oil; therefore, an approach is needed to inhibit this oxidative process. Clove flowers (Syzygium aromaticum) contain bioactive compounds with antioxidant activity that have the potential to be used to reduce oil oxidation. This study aimed to analyse the effectiveness of various concentrations of clove flower extract in reducing the peroxide value of used cooking oil obtained from fried food vendors in the Baturraden area. The study employed apost-test-only control group experimental design with five treatment groups: a control group without extract and groups with clove flower extract added at various concentrations, with six replicates in each group. The clove flower extract was prepared using the maceration method with 70% ethanol, whilst the peroxide value was determined using the iodometric titration method. The data were analysed using the Shapiro–Wilk test, the homogeneity test, One-Way Analysis of Variance, and Tukey’s test. The results showed that the addition of clove flower extract resulted in a greater reduction in the peroxide value as the concentration increased. Comparisons between groups revealed that some concentrations produced a significant reduction compared with the control, whilst the lowest concentration did not yet show a significant difference. The treatment also affected the organoleptic characteristics of the oil. Clove flower extract has the potential to be used as a natural source of antioxidants to inhibit the oxidation of used cooking oil; however, further research is required regarding safety, stability, characterisation of bioactive compounds, and optimal conditions for use.