The pisco and wine industry produces hundreds of tons of grape pomace each year in Chile,generating environmental problems,and demanding urgent strategies for its management.The aim of this work was to study the pisco...The pisco and wine industry produces hundreds of tons of grape pomace each year in Chile,generating environmental problems,and demanding urgent strategies for its management.The aim of this work was to study the pisco grape pomace based on a physicochemical characterization,an iron/copper speciation analysis,and the optimization for polyphenols recovery,establishing the polyphenolic profile,antioxidant properties,and the Fe2+/Cu2+ chelating activity,to promote their revalorization as an ingredient with potential application in the food industry.The chemical characterization showed mainly high values for crude protein(15.36%dw)and potassium(9240.66 mg/kg).The Fe/Cu speciation depicted that iron and copper soluble forms in pisco pomace flour represented 70.57%and 52.18%,respectively,regarding total content.The optimized extract showed mainly pyrogallol,catechin and epicatechin,with concentrations of 1078.43±60.14μg/g,883.20±7.57μg/g and,751.76±23.04μg/g,respectively,with a relevant antioxidant capacity by Oxygen Radical Absorbance Capacity(ORAC)of 1402.15μmol TE/g dw GPE and,a better chelating ability to complex Fe2+ than Cu2+.The pisco pomace was for the first time chemically characterize,showing it as a potential source of minerals and antioxidant biocompounds,making it a good candidate for nutritional applications,as a rich source of organic matter or even could be potentially utilized to produce value-added commodities,toward a circular economy.展开更多
Background:The increasing incidence of degenerative diseases has attracted the interest in the obtaining of bioactive compounds.Since seeds and skins from grapes are important sources of polyphenols which have been as...Background:The increasing incidence of degenerative diseases has attracted the interest in the obtaining of bioactive compounds.Since seeds and skins from grapes are important sources of polyphenols which have been associated with cancer incidence decreasing,then,one of the pisco(alcoholic beverage made of grape)manufacturing byproduct such as lees,could be a potential source of polyphenols.Supercritical fluid extraction is an environmentally friendly technique that has been applied for obtaining polyphenols.Carbon dioxide is used as unique or main extraction solvent instead of organic solvents,most of them toxics and responsible for reducing the application fields of the extracts.For that reason,among others,supercritical fluid extraction is preferred over conventional techniques for obtaining bioactive compounds.The aim of this work was to study the supercritical fluid extraction of polyphenols from lees of pisco-making.Supercritical carbon dioxide with 10%of ethanol(w/w)was used as extraction solvent.Overall extraction curves were determined at 20 and 35 MPa;and the experimental data were used to estimate the kinetic parameters.Conventional techniques using ethanol as extraction solvent were performed for comparative purposes.The extracts were analyzed by thin-layer and high-performance liquid chromatography.Results:Lower global yield was obtained by supercritical fluid extraction than conventional techniques.From the kinetic parameters,the mass transfer rate and the amount of the extract dissolved in supercritical phase were higher at 20 than 35 MPa.Phenolic acids(gallic,protocatechuic,vanillic,syringic,ferulic derivatives and p-coumaric derivatives)and flavonoids(quercetin and its derivatives)were identified in the extracts obtained by all extraction techniques.Polyphenols were rapidly extracted with supercritical fluid and more concentrated extracts were obtained at 20 MPa.However,for longer extraction times,the highest values of extracted polyphenols were obtained by conventional techniques.Conclusions:Lees from pisco-making are a promising source for recovery polyphenols.Low global yields were obtained when elevated pressures were used.Although supercritical fluid extraction at 20 MPa was the most efficient technique on the extraction of polyphenols from lees of pisco-making due to highly concentrated polyphenols,extracts were rapidly obtained.展开更多
摘要The pisco and wine industry produces hundreds of tons of grape pomace each year in Chile,generating environmental problems,and demanding urgent strategies for its management.The aim of this work was to study the pisco grape pomace based on a physicochemical characterization,an iron/copper speciation analysis,and the optimization for polyphenols recovery,establishing the polyphenolic profile,antioxidant properties,and the Fe2+/Cu2+ chelating activity,to promote their revalorization as an ingredient with potential application in the food industry.The chemical characterization showed mainly high values for crude protein(15.36%dw)and potassium(9240.66 mg/kg).The Fe/Cu speciation depicted that iron and copper soluble forms in pisco pomace flour represented 70.57%and 52.18%,respectively,regarding total content.The optimized extract showed mainly pyrogallol,catechin and epicatechin,with concentrations of 1078.43±60.14μg/g,883.20±7.57μg/g and,751.76±23.04μg/g,respectively,with a relevant antioxidant capacity by Oxygen Radical Absorbance Capacity(ORAC)of 1402.15μmol TE/g dw GPE and,a better chelating ability to complex Fe2+ than Cu2+.The pisco pomace was for the first time chemically characterize,showing it as a potential source of minerals and antioxidant biocompounds,making it a good candidate for nutritional applications,as a rich source of organic matter or even could be potentially utilized to produce value-added commodities,toward a circular economy.
基金providing the raw material and CNPq(190667/2010-9)and FAPESP(2009/17234-9 and 2013/04304-4)for financial support。
摘要Background:The increasing incidence of degenerative diseases has attracted the interest in the obtaining of bioactive compounds.Since seeds and skins from grapes are important sources of polyphenols which have been associated with cancer incidence decreasing,then,one of the pisco(alcoholic beverage made of grape)manufacturing byproduct such as lees,could be a potential source of polyphenols.Supercritical fluid extraction is an environmentally friendly technique that has been applied for obtaining polyphenols.Carbon dioxide is used as unique or main extraction solvent instead of organic solvents,most of them toxics and responsible for reducing the application fields of the extracts.For that reason,among others,supercritical fluid extraction is preferred over conventional techniques for obtaining bioactive compounds.The aim of this work was to study the supercritical fluid extraction of polyphenols from lees of pisco-making.Supercritical carbon dioxide with 10%of ethanol(w/w)was used as extraction solvent.Overall extraction curves were determined at 20 and 35 MPa;and the experimental data were used to estimate the kinetic parameters.Conventional techniques using ethanol as extraction solvent were performed for comparative purposes.The extracts were analyzed by thin-layer and high-performance liquid chromatography.Results:Lower global yield was obtained by supercritical fluid extraction than conventional techniques.From the kinetic parameters,the mass transfer rate and the amount of the extract dissolved in supercritical phase were higher at 20 than 35 MPa.Phenolic acids(gallic,protocatechuic,vanillic,syringic,ferulic derivatives and p-coumaric derivatives)and flavonoids(quercetin and its derivatives)were identified in the extracts obtained by all extraction techniques.Polyphenols were rapidly extracted with supercritical fluid and more concentrated extracts were obtained at 20 MPa.However,for longer extraction times,the highest values of extracted polyphenols were obtained by conventional techniques.Conclusions:Lees from pisco-making are a promising source for recovery polyphenols.Low global yields were obtained when elevated pressures were used.Although supercritical fluid extraction at 20 MPa was the most efficient technique on the extraction of polyphenols from lees of pisco-making due to highly concentrated polyphenols,extracts were rapidly obtained.