TITLE:
Kinetic of Forced Oxidation of Grape Seeds, Walnuts and Corn Germs Oils in the Presence of Antioxidants
AUTHORS:
Iurie Subotin, Raisa Druta, Violina Popovici, Ecaterina Covaci, Rodica Sturza
KEYWORDS:
Lipids, Accelerated Oxidation, Inhibition, Antioxidants, Oils
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.12 No.12,
December
27,
2021
ABSTRACT: The present study aimed to investigate the
effectiveness of the use of some antioxidants-α-tocopherol, n-octyl gallate, L-ascorbic acid 6-palmitate and
matcha extract (green tea) as inhibitors of grape seeds, walnuts and corn germ
oils oxidation. The oxidation was studied in a forced regime during 700 h, by
the addition of hydrogen peroxide and Cu2+ ions. The optimal
conditions of the accelerated oxidation process in the analysed systems were
established. The progress of lipid oxidation was evaluated by measuring the
peroxide value (PV) and conjugated dienes and trienes (CD, CT). A series of secondary
products of the lipid oxidation were identified: hexanal, octanal and
hydroxy-nonadienal. The intensity of the formation of these compounds during
oxidation was monitored. The results of this study showed that the oil samples
with the addition of antioxidants showed considerably lower oxidation values
compared to the control sample. More effective was the action of L-ascorbic
acid 6-palmitate and n-octyl gallate, the optimum concentration was 0.1%. An inhibitory effect of the oxidation
process was noted for α-tocopherol
and matcha extract, the optimal addition concentration was 1%.