Ultrasound‐Assisted Extraction of Oil from Chia (Salvia hispânica L.) Seeds: Optimization Extraction and Fatty Acid Profile

Abstract

AbstractThe objective of the present study was to evaluate ultrasound‐assisted extraction (UAE) to obtain oil from chia seeds (Salvia hispânica L.). A Box–Behnken design was applied to investigate and optimize the process variables (temperature, solvent to seed ratio and time) for oil yield. The solvent to seed ratio and temperature had the greatest influence on oil yield, followed by the extraction time (P < 0.05). An extraction temperature of 50C, a solvent to seed ratio of 12 mL/g and 40 min of extraction were identified as the optimal conditions, with 27.24% oil yield. The application of ultrasound resulted in higher oil yield when compared with the process without ultrasound (P < 0.05). The fatty acid composition extracted by UAE was similar to that of oil extracted using other extraction methods. Linolenic acid (∼66%) and linoleic acid (∼20%) were the main fatty acid constituents of chia seed oil. The quantity of unsaturated fatty acids was higher than saturated fatty acids.Practical ApplicationThe chia seed oil is considered one of the greatest sources of linoleic and linolenic acid and the extraction demonstrated high efficiency by UAE. Chia oil obtained by UAE using ethyl acetate with solvent may be used as a food, accepted in the food industry, because the solvent is considered a food‐grade solvent. The effect of different parameters such as temperature, the solvent to seed ratio and extraction time in the UAE provided high yields in the extraction, and the chemical analyses indicated polyunsaturated fatty acids, are the major oil components (82% of the total oil composition).