Supercritical Fluid Extraction: A Review

Abstract

INTRODUCTION: Across globe research is been conducted to assess the efficacy of many emerging non-thermal technologies in food processes to minimize the deleterious effects of thermal conventional process like, pulsed electric field 1 , Ohmic heating 2 , ultraviolet light 3 , pulsed-light technology 4,5 , ultrasound 6 , cold plasma 7 , high hydrostatic pressure 8 and ultra-high pressure homogenization 9. Consumers crave for food with better nutritional quality, coupled with food safety and use of green technology. 10 The number of potential applications for supercritical fluid extraction (SFE) continues to grow globally, which is verified through the increase in patents deposited in the last few years. It is observed that its application is already part of the present scenery, being mainly impelled by the growing demand of high quality products demand and economy's globalization. Besides that, it also stands out in its use in the commerce of pharmaceutical, food, chemical, and cosmetic materials. The increase in the application of this technology in the industrial area is mainly due to the selectivity, facility, and separation capacity that the technique allows in obtaining a great number of organic compounds, of which many are impossible or nonviable to extract through traditional processes, or those whose purification needs high resolution columns , not always available in the national market, thereby making the utilization very costly. The high utilization of organic solvents in the different industrial processes, such as fat and oil extraction, obtaining bioactive functional compounds, removal of heavy metals, polymer processing, fuel production, among others, represent a globally discussed issue, due to the harm caused to the environment. In light of this picture, in 1987, the Montreal Protocol was introduced, and in 1997 the Kyoto Protocol, which had as the main objective to restrict or eliminate the production and utilization of solvents that cause harm to the ozone layer. 11 The great interest of the scientific community and the industrial sector for SFE is directly related to the restrictions to the use of organic solvents, both in the preparative processes of samples used in the various industries, and in a higher ecological consciousness in the use of different analysis methods involving extraction. The extraction technique most widely known as supercritical fluid Extraction (SFE) Since its inception has been touted for its exceptional performance. 12 Presently, the utilization of SFE is extensively applied not only to the food and drug areas, but also in the areas of toxicology, chemistry, environment, textile, petrochemical, polymers, among others. 13 Significant

Recent Advances in Supercritical Fluid Extraction of Natural Bioactive Compounds from Natural Plant Materials

“…SC-CO 2 has numerous benefits. It is a cheap and readily available in large quantities with a high degree of purity [ 28 ], furthermore it is an environmentally friendly substitute for organic solvents and is designated as a safe solvent by different organizations such as the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) [ 35 , 36 ].…”

“…CO 2 is useful in supercritical fluid extraction processes because being close to the ambient environmental conditions it can readily penetrate through plant material and dissolve the targeted extracts. However, its extractability with substances depends on the occurrence of specific groups in the structure, as well as their polarity and molecular weight [ 13 , 35 , 37 ]. Additionally, the extract composition for volatiles or non-volatiles can be changed easily by modifying the pressure and temperature conditions.…”

Emerging Green Techniques for the Extraction of Antioxidants from Agri-Food By-Products as Promising Ingredients for the Food Industry

“…In general, SFE is able to increase the extraction yields; at the same time, the absence of organic or toxic solvent residues in the extraction products eliminates further purification steps, which makes it economically acceptable at an industrial scale. However high-pressure equipment and accurate temperature and pressure monitoring need high initial investment on an industrial scale [ 54 , 55 ].…”

Processos de extração e usos industriais de óleos de andiroba e açaí: uma revisão

“…Este processo consiste na utilização de fluído supercrítico, onde o dióxido de carbono (CO2) é o mais amplamente utilizado, por ser atóxico, não inflamável, não corrosivo e de fácil manipulação, permitindo operação supercrítica em baixas pressões e temperaturas próximas a ambiente (Ahmad et al, 2019). Esta técnica é muito utilizada nas indústrias farmacêuticas, alimentícias, químicas e de cosméticos devido ao grande interesse nesta tecnologia estar diretamente relacionado com as restrições ao uso de solventes orgânicos, além da redução no tempo de extração (Silva et al, 2016).…”