Green solvents, potential alternatives for petroleum based products in food processing industries

• Use of solvent extraction in food processing is discussed. • Petroleum based solvents are easily available but possess health hazard. • Green solvents have bio-based origin and are environmentally safe. • Green solvents have been reported to possess similar or higher extraction efficacy. • Toxicity and environmental implications of green solvents is discussed. Solvent extraction is used at the industrial scale for extraction of oil, flavouring and functional compounds from the source materials. Easy availability at lower price makes petroleum based solvents (e.g., hexane, petroleum ether, etc.) the preferred choice for solvent extraction. However, some amount of the solvent always escapes to the environment during the extraction process and the yield product also contains some amount of residual solvent. This causes hazard not only to the environment and people at large, but also affects the manpower involved in the solvent extraction industry in particular. This has led to the search of alternative solvents which have lower toxicity and are environmentally safe. Green solvents appear to be a potential candidate for this. Solvent extraction studies performed using green solvents have revealed their equal or higher extraction efficacy to that of petroleum based products. This review paper aims to provide comprehensive information about the studies pertaining to the application of green solvents as a safer and their potential for replacement of petroleum based solvents for extraction of fat soluble compounds. In addition, health and environmental aspects of greens solvents along with their associated advantages-disadvantages has also been discussed in this paper.