Optimization of lycopene extraction from tomato peels industrial by-product using maceration in refined olive oil

By-Products from Winemaking and Olive Mill Value Chains for the Enrichment of Refined Olive Oil: Technological Challenges and Nutraceutical Features

“…In the operating conditions adopted, according to ANOVA the best results were obtained when olive leaves were used as a source of phenols, regardless of the chemical composition of the solvent utilized for the extraction. As regards the solvent, the results showed significantly ( p ≤ 0.001) different efficiency for the ROO fortification depending on the matrix used: for pomace, ethanol seems to be the best solvent according to the total phenols content; on the contrary, for grape marc and olive leaves the mix Ethanol/Hexane (1:1 kg/kg) was elected the best extracting solution, probably for a synergic effect between the two solvents [ 12 ]; always considering grape marc and olive leaves as sources for phenolic recovering, the mix ROO/Ethanol (1:1 kg/kg) also showed a good extracting power, representing a good compromise also considering its reduced toxicity.…”

“…In recent years refined olive oils are gaining importance in the food industry even thanks to the increasing importance of olive oil in the global market. As ROOs generally show reduced or absent minor components because of the refining process, some different strategies to produce functional ROOs with improved nutraceutical value were recently investigated [ 8 , 12 , 25 , 53 ]. When the content in antioxidant and anti-inflammatory compounds was significantly increased, the enriched ROOs generally showed an extended shelf life as well as an encouraging behavior in counteracting health degeneration in both in vivo and in vitro models.…”

“…Based on the recent literature [ 12 ] and on our previous experience in the recovery of antioxidant compounds from different food by-products [ 13 , 23 , 34 ], the preparation of the PE-ROO was carried out according to the scheme reported in Figure 1 and further discussed.…”

“…Fatty acid composition is similar in all the commercially available types of oils but minor components, mainly phenolic compounds that are assumed to be one of the healthiest fractions of olive oil, are depleted in ROO as they are lost during the extraction and refining procedures [ 1 ]. Due to the reduced or totally absent content of phenols [ 9 , 10 ], ROO is unstable and subjected to rapid oxidation during storage [ 8 , 11 , 12 , 13 ]. Furthermore, since organoleptic properties of ROO are very poor, it is usually commercialized and consumed as a component of mixed olive oil, which is ROO with a low percentage (10–15%) of VOO to improve palatability.…”

“…In the last few years, a growing body of literature has become available about the valorization of olive pomace, olive leaves, and grape marc as a source of valuable antioxidant compounds to be used to produce functional foods in a circular economy concept [ 25 , 26 , 27 , 28 , 29 , 30 ]. Besides, several studies have focused on the optimization of new methods for the production of OO and ROO enriched with natural antioxidants (namely phenols, tocopherols, carotenoids) extracted from different food wastes [ 12 , 13 , 26 , 31 ]. However, to the best of our knowledge, the main issues related to the industrial production of phenol-enriched refined olive oil (PE-ROO) are yet to be solved and no data is available in the literature on the feasibility of the use of grape marc, olive leaves, and pomace as a source of safe natural antioxidants to be used with this specific aim.…”