Technologies for extraction of oil from oilseeds and other plant sources in retrospect and prospects: A review

Abstract

AbstractThe vegetable oils are obtained from the oilseeds and also from other oil bearing parts of plants like fruits (mesocarp and/or stones), tubers, germs, sprouts, and so on. A host of methods are employed to obtain the oil from different matrices and each method has its own set of advantages and disadvantages. The traditional methods of oil extraction are exhaustive and have low efficacy, while conventional method of mechanical pressing is simple and involves low cost but considered as an inefficient method because of low oil recovery when compared with chemical extraction methods. Due to higher oil recovery and economic gains, chemical methods of oil extraction are preferred globally; however, the chemical solvents used exhibited detrimental effect on the environment, oil quality, and human health, which impelled the development of new technologies. New advanced eco‐friendly techniques namely, enzyme‐assisted extraction, microwave‐assisted extraction, ultrasound‐assisted extraction, and supercritical fluid extraction can easily overcome the shortcomings of the conventional methods and holds the potential to meet the ever‐increasing demand of edible oils.Practical applicationsLimited land availability and growing demands for vegetable oils call for the development of improved cultivars for harnessing higher yields as well as more efficient oil extraction technologies to augment oil recovery from different oilseed crops without compromising with the oil quality. Widely practiced traditional and conventional methods of extraction have various disadvantages namely, use of solvents, protractive protocols, and have adverse effects on environment, oil quality, and human health. Therefore, in order to overcome the demerits associated with the existing methods, green extraction technologies have been developed as an alternative, which offer various advantages like less extraction time, high extraction yields, and quality and minimized solvent consumption. The information compiled in this review on various extraction technologies will help oilseed processors and researchers in choosing the most appropriate method of oil extraction in order to achieve high yields without compromising the inherent quality of oil.