Optimization of parameters for enhanced oil recovery from enzyme treated wild apricot kernels

Optimization and characterization of aqueous enzyme-assisted solvent extraction of apricot kernel oil

Abstract

Aqueous enzyme-assisted solvent extraction (AE-SE) of oil from apricot (Prunus armeniaca L.) kernel was investigated in this study and the operational parameters were optimized. After preliminary screening, a cocktail of enzymes (Celluclast 1.5 L and Alcalase Pure 2.4 L [60:40, v/v)] of 1% (v/w) was chosen. The extraction process parameters: temperature (40-60 °C), time (1-5 h), and pH (4-9) were optimized using Box-Behnken design to achieve the highest oil yield (%) and antioxidant activity (DPPH, %). Under optimized conditions, i.e., temperature 40 °C, time 2.5 h, and pH 8.28, the highest oil yield and DPPH were 47.93% and 67.31%, respectively. The gas chromatography analysis disclosed that apricot kernel oil extracted by solvent extraction and AE-SE have similar fatty acid compositions, and the oil is rich in unsaturated fatty acids. The physicochemical analysis showed AE-SE method produces high-quality oil and can be substituted as green technology for industrial oil extraction purposes.

Graphical abstract

Apricot kernel characterization, oil extraction, and its utilization: a review

Apricot (Prunus armeniaca L.) kernels, one of the economical stone fruit kernels, are utilized worldwide for edible, cosmetic, and medicinal purposes. Oil from the apricot kernel is valued by the richness of unsaturated fatty acids, the high proportion of oleic acids, phenols, and tocopherol content. Oil yield with quality from apricot kernel varies with region, variety, and adopted method of oil extraction. This review discusses apricot kernel characterization, different conventional and novel methods of oil extraction, their merits and demerits as reported in the literature. Novel technologies such as microwave-assisted oil extraction, ultrasound-assisted oil extraction, enzyme-assisted oil extraction, and supercritical fluid oil extraction have emerged as the most promising extraction methods that allow efficient oil recovery in very environment-friendly ways. Knowledge of the extraction technique aids in giving higher oil recovery with minimal nutritional losses while retaining the original organoleptic properties.

Graphical abstract