Optimization of polyphenol extraction from red grape pomace using aqueous glycerol/tartaric acid mixtures and response surface methodology

Prep Biochem Biotechnol. 2016;46(2):176-82. doi: 10.1080/10826068.2015.1015562.

Abstract

Grape pomace is a food industry waste containing a high burden of antioxidant polyphenols and several methodologies have been developed for their efficient extraction. However, a sustainable and environmentally friendly process should involve recovery means composed of benign, non-toxic solvents, such as tartaric acid and glycerol, which are natural food constituents. In this line, this study examined the extraction of polyphenols using aqueous tartaric acid/glycerol solutions. The aim was to assess the role of acid and glycerol concentration in the extraction yield, employing a Box-Behnken experimental design and response surface methodology. The results showed that solutions containing only glycerol (20%, w/v) are more suitable for retrieving polyphenols, flavonoids, and pigments from grape pomace, while tartaric acid exerted a negative effect in this regard, when tested at concentrations up to 2% (w/v).

Keywords: Antioxidants; extraction; glycerol; polyphenols; red grape pomace; tartaric acid.

MeSH terms

  • Biochemistry / methods*
  • Food-Processing Industry
  • Glycerol / chemistry
  • Polyphenols / isolation & purification*
  • Solvents / chemistry
  • Tartrates / chemistry
  • Vitis / chemistry*
  • Waste Products

Substances

  • Polyphenols
  • Solvents
  • Tartrates
  • Waste Products
  • Glycerol
  • tartaric acid