1. Characterization of red wine native colloids by asymmetrical flow field-flow fractionation with online multidetection
- Author
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Valentina Marassi, Pierluigi Reschiglian, Andrea Curioni, Andrea Zattoni, Barbara Roda, Andrea Versari, Simone Vincenzi, Matteo Marangon, Valentina Marassi, Matteo Marangon, Andrea Zattoni, Simone Vincenzi, Andrea Versari, Pierluigi Reschiglian, Barbara Roda, and Andrea Curioni
- Subjects
General Chemical Engineering ,Multiangle light scattering ,Fractionation ,Polysaccharide ,Macromolecule ,01 natural sciences ,Colloid ,Red wine, Colloids, Flow-field flow fractionation, Multi angle light scattering, Macromolecules, Phenolics ,0404 agricultural biotechnology ,0103 physical sciences ,Native state ,Colloids ,Multi angle light scattering ,Wine ,chemistry.chemical_classification ,Chromatography ,010304 chemical physics ,Chemistry ,Extraction (chemistry) ,digestive, oral, and skin physiology ,Red wine ,food and beverages ,04 agricultural and veterinary sciences ,General Chemistry ,040401 food science ,Flow-field flow fractionation ,Macromolecules ,Phenolics ,Food Science - Abstract
Colloids are an important component of wines, but their study is challenging due to their instability. Asymmetrical Flow-Field Flow Fractionation (AF4)-multidetection is here proposed as a suitable approach to isolate and characterize red wine colloids in native state. AF4 provided size-separation and enabled quantification of the colloidal content of two wines. The gyration radius of colloids was determined by multi-angle light scattering, and ranged between 25 and 50 nm. Analysis of the collected AF4-fractions showed that proteins, polysaccharides and phenolics were present in different proportions among fractions. The composition of AF4-fractions differed between wines. SDS-PAGE analysis of AF4-fractions indicated the presence of protein-phenolics sub-aggregates only in the fractions containing colloids with small radius. The results allowed proposing a model for red wine colloids structure, which comprises two coexisting entities, one made of covalently linked proteins-phenolics sub-aggregates interacting by non-covalent forces with polysaccharides, and a second in which only polysaccharides and phenolics are present. The proposed model is consistent with the reported relative stability of red wine proteins, a fact that can be due to the stabilizing activity of polysaccharides. Given that enological practices affect the extraction of proteins, polysaccharides and phenolics, AF4-technique represents a very promising tool to investigate the effects of these practices on wine colloidal aggregation and behavior.
- Published
- 2021