Natural extracts of soursop flowers, aged green tea leaves, and ginger rhizomes mitigate thermo‐oxidative degradation of palm olein during plantain chip deep‐frying

Abstract This work was designed to assess the effect of extracts from three plants: soursop flowers, old green tea leaves, and ginger rhizomes on the oxidative stability of palm olein during deep‐frying of plantain chips. For each extract, oil samples were prepared at concentrations of 1000, 1400, and 1800 ppm. Butylated hydroxytoluene (BHT) was used as a positive control while the oil without additive served as negative control. Samples were prepared in duplicate. The oil samples obtained were used for deep‐frying of plantain chips at 180°C for 18 h, with 3 h of frying per day (8 frying cycles). Samples were collected at 0, 6, 12, and 18 h for analysis. Results showed that at 18 h, oils supplemented with the BHT at 200 ppm and plant extracts at concentrations 1000, 1400, and 1800 ppm reduced TOTOX value by 15.48%, 6.18%–22.97%, 14.35%–19.98%, and 10.46%–19.52%, respectively, compared with the control. Linoleic acid retention in the control, that with BHT 200ppm , and those with extracts at concentrations 1000, 1400, and 1800 ppm were respectively 68.10%, 80%, 76.66%–77.23%, 76.65%–79.15%, and 76.75%–77.61%. These plant extracts could be recommended as good substitutes for chemical antioxidants pending further safety and standardization approval.