The quality and volatile-profile changes of Longwangmo apricot (Prunus Armeniaca L.) kernel oil prepared by different oil-producing processes

Quality parameters and volatile profiles were determined for Longwangmo apricot (Prunus armeniaca L.) kernel oil prepared by cold pressing, heat pressing, and refining of sun-dried and baked apricot kernels. Quality parameters determined included peroxide value, acid value, fatty acids, and UV absorbance. The tested oils showed absorbance values at 232 and 268 nm of 0.70–0.85 and 0.20–0.38, respectively; peroxide values were 2.09–5.62 mmol O₂/kg and acid values were 0.36–1.40 mg KOH/g. The major fatty acid composition found in the oils was oleic acid (70.29–71.25%) followed by linoleic (22.31–23.00%), palmitic (4.57–4.87%), stearic acids (4.57–4.87%), palmitoleic acid (0.62–0.71%), and α-linolenic acid (0.15–0.18%). The numbers and concentrations of volatile compounds in the oils ranged from 19–52 to 6172–23871 μg/g, respectively. Nine compounds were present, in different amounts, in all apricot kernel oils studied: benzaldehyde, 2-methyl-propanal, 2-methyl-butyl aldehyde, furfural, nonanal, methylpyrazine, 2,5-dimethyl-pyrazine, methoxy pyrazine, and 3-ethyl-2,5-dimethyl-pyrazine. The results of our present investigation revealed that the oil-producing process had significant influence on the volatile profiles of apricot kernel oil. In particular, the baked–pretreatment process may enhance the aroma of apricot kernel oil by increasing the number and quantity of volatile compounds.