ABSTRACT
Various techniques are applied to extract essential components from raw materials for food and biological products. Foods that are rich in biologically active compounds like dietary fiber, carotenoids, vitamins, omega-3 fatty acids, minerals, and antioxidant components such as phenolics, carotenoids, anthocyanins, tocopherols, flavonoids and essential oils, are used commercially in the pharmaceutical, chemical, and food industries. Suitable and standard processes to extract these compounds are required. Traditional techniques are solvent extraction, distillation, sublimation, and pressing. Modern or greener extraction methods include pressurized liquid extraction (PLE), supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), high voltage electric discharges assisted extraction (HVEDAE), pulsed electric field-assisted extraction (PEF), and high-pressure assisted extraction (HPAE). These techniques are highly selective processes that provide advantages such as reduced utilization of organic solvents and minimized extraction time. Enzyme-assisted extraction produces fewer undesired products and has a lower environmental impact. Natural materials can also be segregated using membrane filtration or gel filtration chromatography based on their molecular sizes. These innovative techniques not only improve process safety, reduce extraction time, decrease the risk from chemicals, and minimize solvent consumption; they also produce essential high-quality components and represent a viable alternative sample preparation method for analytical purposes.
