Pulsed electric energy-assisted biorefinery of oil crops and residues

Abstract

The different oil-bearing plant products are widely used for production of edible and essential oils. The modern processing technologies for recovery of oils are mainly based on application of pressing or solvent extraction or their combination. Besides the oils the utilization of wastes, press cakes, the remaining straw, stem, leave, root, and flower represents the interest for oil crop biorefinery. These by-products are rich in proteins, fatty acids, secondary metabolites, polyphenols, and value-added antioxidants which could be used in pharmacy, medicine, cosmetic, food industry, and for production of chemicals. The efficiency of extraction of oils and high-added substances can be noticeably enhanced by application of feedstocks pretreatment or combined treatment based on different thermal, chemical, enzymatic, ultrasonic, and microwave-assisted techniques. Recent efforts have shown promising examples on applications of pulsed electric energy (PEE) to enhance electroporation and to improve different operations with oil-bearing plant products, their residues, and wastes. Several groups have tested efficiency of electroporation for extraction of edible oils from linseed, maize, olive, soybean, rapeseed, and sesame and essential oil from oil-bearing roses, nepeta, seeds of coriander and lovage, patchouli leaves, lime peels, and peppermint. The tested products and modes of PEE-assisted operations are still limited. However, the results evidence the positive effects of PEE on extraction yield and the quality of oils during the storage. Moreover, PEE techniques have been also checked for extraction of polyphenols and proteins from flaxseed cake and hulls and rapeseed stems and leaves. This chapter analyzes the up-to-date information available on a PEE-assisted biorefinery oil crops and their residues.