Electrostatic adsorption and removal mechanism of ochratoxin A in wine via a positively charged nano-MgO microporous ceramic membrane

Food Chem. 2022 Mar 1:371:131157. doi: 10.1016/j.foodchem.2021.131157. Epub 2021 Sep 17.

Abstract

Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine. The isotherm adsorption between the positively charged membrane and OTA was in accordance with the Langmuir model, with a maximum adsorption capacity of 806 ng/g at 25 °C. All of the changes in adsorption enthalpy (ΔH), adsorption free energy (ΔG) and adsorption entropy (ΔS) were negative, which indicated that the combination of nano-MgO MCM and OTA was a spontaneous exothermic and nonspecific physical adsorption process. The concentrations of OTA in adsorption-treated wines were lower than 2 μg/kg, and the removal rates exceeded 92%. After OTA removal, the composition of wines was preserved to some extent.

Keywords: Electrostatic adsorption; Ochratoxin A; Positively charged nano-MgO microporous ceramic membrane; Removal; Wine.

MeSH terms

  • Adsorption
  • Ceramics
  • Ochratoxins* / analysis
  • Static Electricity
  • Wine* / analysis

Substances

  • Ochratoxins
  • ochratoxin A