The effect of heat treatment of java plum seed extract on its polyphenolics content and antioxidant activities

Abstract

Butylated hydroxy anisole (BHA) is widely added in lipid and food lipid as a preservative and it is effective for inhibiting lipid peroxidation. However, BHA raised doubt would be the health impact for consumers. The methanolic extract of Java Plum seed (MEJS) contains a diverse group of phenolic compounds, it has potential as a natural antioxidant. The objective of the research was to determine the effect of heating treatment on total phenolics content and antioxidant activity of MEJS. Heating treatment applied on MEJS at 110, 120, 130, 140 and 150oC/10 minutes and heating time (10, 15, 20, 25 and 30 minutes/110oC). The results showed that heating of the extract at the temperature rose to 130oC should decrease the total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) slightly, coincided with a decrease of the reducing power, but it could increase the free radical scavenging activity. Heating treatment at 110oC for about first ten minutes had a positive impact on increasing of its phenolics content and antioxidant activities. However, heating further at a higher temperature (>130oC) gave a bad influence on the free radicals scavenging activity. The extract heated at the 130oC/10 minutes gave the best EC50 value as 140 ppm.