Asymmetric Flow Field-Flow Fractionation for the monitoring of red wine colloids and macromolecules throughout the winemaking process

Daniel Eduardo Osorio Macías^1,2Raul Ferrer-Gallego³Jaeyeong Choi⁴Bjorn Bergenstahl^1*

• ¹Division of Food and Pharma, Department of Process and Life Science Engineering, Faculty of Engineering, Lund University, Lund, Sweden
• ²School of Chemistry, Faculty of Pure and Natural Sciences, Universidad Mayor de San Andrés, La Paz, La Paz, Bolivia
• ³Department of Ecology, Desertification Research Centre, University of Valencia, Valencia, Spain
• ⁴Department of Chemistry, Hannam University, Daejeon, Republic of Korea

Colloids and macromolecules are the major compounds in wine particulate matter, playing an important role in many wine properties that change during the winemaking process. However, a lack of methodologies allows us to characterize and quantify the changes these compounds experience throughout the winemaking process. This work uses asymmetric flow-field fractionation coupled to multiple detectors (AF4-MALS-dRI-UV) to separate, characterize, and quantify colloidal and macromolecular properties. In addition, useful information is provided on the evolution and dynamics of these colloidal and macromolecular fractions throughout five winemaking stages.The results showed that the technique (AF4-MALS-dRI-UV) allows us to monitor the changes in specific colloidal and macromolecular properties during the winemaking process. In this study, three populations were separated and classified according to their nature and main properties throughout the winemaking process. It was observed that concentration, c, and specific absorptivity (ε) tend to change more depending on the wine variety and the vinification stage. However, the maturation and aging stages tended to stabilize changes in the early stages. In contrast, properties such as hydrodynamic radius (rH), molar mass (MW) and usually the apparent density (𝜌 ̂) tend to remain more stable as the winemaking process is carried out.The results demonstrated the use of AF4-MALS-dRI-UV as a robust and feasible technique to separate the wine particle matter and to monitor fundamental colloidal and macromolecular properties in a wide variety of samples without the support of additional techniques throughout the winemaking process.