Essential oil extracted from peach (Prunus persica) kernel and its physicochemical and antioxidant properties

Abstract

Peach kernel oil was extracted using Soxhlet extraction with different solvents (petroleum ether, ethyl ether, chloroform and hexane). The physicochemical properties (acid value, iodine value, peroxide value and saponification value), the fatty acid composition, phenolic constituents and contents, and antioxidant activities of peach kernel oil were examined. As per our results, oil extracted with hexane has better overall quality. Its acid, peroxide, iodine and saponification values were 0.895 mg KOH/g oil, 0.916 mg/g oil, 36.328 mg/100 g oil and 101.836 mg KOH/g oil, respectively. Large proportions of unsaturated fatty acid (91.27%) and high content of phenolic compounds (4.1593 mg GAE/g), which contribute to considerably strong antioxidant activity, were found in oil. The main fatty acids found in the peach kernel oil were oleic acid (61.87 g/100 g oil) and linoleic acid (29.07 g/100 g oil). The HPLC analysis of phenolic compounds showed that rutin, (-)-epicatechin gallate, hydrocinnamic acid, sinopinic acid, dithiothreitol and caffeic acid were major constituents. The results suggested that peach kernel oil is a good source of the unsaturated fatty acid, phenolic compounds with strong antioxidant activity, and has the potential to be used as nutrient rich food oil. The results also verified that peach kernel meals contained higher amounts of total phenolic and stronger antioxidant activities than oils, enabling their application as ingredients for functional or enriched foods.