Insights on the use of alternative solvents and technologies to recover bio‐based food pigments

Abstract

This review will discuss, under the Circular Economy and Biorefinery concepts, the performance of the alternative solvents in the downstream process to recover natural pigments in a more sustainable way. Conventionally, pigments marketed on an industrial scale are produced through chemical synthesis by using petroleum derivatives as the main raw material. Also, the current production chain of the synthetic dyes is linear, with no solvent recycling and waste generation. Thus, the most promising processes of extraction and purification of natural pigments and strategies on the polishing of the solvents are here reviewed. In this review, the use of alternative solvents, namely, ionic liquids, eutectic solvents, aqueous solutions of surfactants, and edible oils, for recovering natural pigments was reviewed. Works discussing higher extraction yields and selectivity, while maintaining the stability of the target pigments, were reported. Also, a panorama between Sustainability and Circular Economy prospection was discussed for better comprehension of the main advances in the field. Behind the analysis of the works published so far on the theme, the most important lacunas to overcome in the next years on the field were pointed out and discussed. Also, the future trends and new perspectives to achieve the economic viability and sustainability of the processes using alternative solvents will be scrutinized.

Phytomanagement of a Trace Element-Contaminated Site to Produce a Natural Dye: First Screening of an Emerging Biomass Valorization Chain

“…The best dyeing results were achieved on the alum-pretreated silk fabrics, which had a bright yellow shade that could be due to the flavonoid content reported in M. sylvestris flowers [25,53]. Such shade could also be obtained from other plant species extracts, such as onions [53]. All of these observations emphasize the importance of pretreating the fabric with alum prior to the dyeing test.…”

“…The orange shade obtained on the iron-pretreated fabrics was mainly due to the pretreatment itself, with the addition of the flower extract only slightly intensifying the color (Figure 3, Supplementary Materials Figure S2). The best dyeing results were achieved on the alum-pretreated silk fabrics, which had a bright yellow shade that could be due to the flavonoid content reported in M. sylvestris flowers [25,53]. Such shade could also be obtained from other plant species extracts, such as onions [53].…”

Bioaccessibility and Cellular Uptake of Carotenoids Extracted from Bactris gasipaes Fruit: Differences between Conventional and Ionic Liquid-Mediated Extraction

“…Under the same perspective, some authors using all- E -βC from cassava suggested that the content of carotenoids in the samples could be a useful marker for assessing BCT without the need for in vitro digestion and animal studies [ 53 ]. Thus, this article also acts as an incentive to promote more experiments regarding the BCT and cellular uptake of compounds extracted using ILs, and other alternative solvents, such as eutectic solvents, aqueous solutions of surfactants, and more recently edible oils (used as promising solvents in the food sector) [ 15 ].…”

“…Additionally, from an environmental perspective, ILs have emerged as promising solvents to replace COS since they can be recycled in new processes [ 6 ], reducing the environmental impact caused by the disposal of underexploited raw materials [ 13 ]. Furthermore, the protocols used to produce most usual synthetic food colorants are unsafe, which promotes the confidence of new consumers [ 14 , 15 ]. Additionally, synthetic dyes are produced by photocatalytic reactions, without recycling of the raw materials (petroleum derivative chemicals), which goes against sustainable chemistry principles, as exposed by the European economic plan based on the circular economy for a cleaner and more competitive society [ 16 ].…”

Supplementation of carotenoids from peach palm waste (Bactris gasipaes) obtained with an ionic liquid mediated process displays kidney anti-inflammatory and antioxidant outcomes

“…Thus, without a precise safety examination, industrial products generated through VOS-based processes cannot be redirected to human consumption. As an alternative to the use of VOS, studies have currently been carried out with non-volatile alternative solvents, mostly the ionic liquids (ILs) and more recently deep eutectic solvents, which are already proved to be efficient alternative solvents replacing VOS-based extractions, in addition to representing a more sustainable option, since it can be recovered, reused and recycled in new (or even different) processes ( de Souza Mesquita, Martins, Pisani, Ventura & de Rosso, 2021 ). However, despite the novelty, the applications of ILs remain poorly explored regarding biological effects, with little evidence of its safe application in vivo models ( de Souza Mesquita, Casagrande et al, 2021d ).…”