Thermal stability of natural antioxidants extracted from Annona muricata flowers, Zingiber officinale roots and Camellia sinensis leaves

The objective of this study was to evaluate the thermal stability of the natural antioxidants extracted from Annona muricata flowers, Zingiber officinale roots and Camellia sinensis leaves. The plant materials were extracted with methanol heated at 180C for 0, 20, 40, 60 and 80 min in an electric air-dried oven. The stability of their antioxidant was measured by testing their radical scavenging activity, ferric reducing antioxidant power and metal chelation ability. Results showed that the activity of the extracts significantly reduces with heating time, but still remain interesting. Practical Applications The natural antioxidants present in these extracts have good thermal stability and can then be used to preserve foods during processing at high temperature.