title: Astringency reduction in red wine by whey proteins.
abstract: Whey is a by-product of cheese manufacturing and therefore investigating new applications of whey proteins will contribute towards the valorisation of whey and hence waste reduction. This study shows for the first time a detailed comparison of the effectiveness of gelatin and β-lactoglobulin (β-LG) as fining agents. Gelatin was more reactive than whey proteins to tannic acid as shown by both the astringency method (with ovalbumin as a precipitant) and the tannins determination method (with methylcellulose as a precipitant). The two proteins showed similar selectivity for polyphenols but β-LG did not remove as much catechin. The fining agent was removed completely or to a trace level after centrifugation followed by filtration which minimises its potential allergenicity. In addition, improved understanding of protein-tannin interactions was obtained by fluorescence, size measurement and isothermal titration calorimetry (ITC). Overall this study demonstrates that whey proteins have the potential of reducing astringency in red wine and can find a place in enology.
authors.affiliation: Dept. of Food and Nutritional Sciences, The University of Reading, RG6 6AP Reading, UK. Electronic address: p.jauregi@reading.ac.uk.
authors.forename: Paula
authors.initials: P
authors.lastname: Jauregi
authors.affiliation: Dept. of Food and Nutritional Sciences, The University of Reading, RG6 6AP Reading, UK.
authors.forename: Jumoke B
authors.initials: JB
authors.lastname: Olatujoye
authors.affiliation: School of Biochemical and Pharmaceutical Sciences, National University of Rosario, Rosario, Argentina.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Cabezudo
authors.affiliation: Dept. of Food and Nutritional Sciences, The University of Reading, RG6 6AP Reading, UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Frazier
authors.affiliation: Dept. of Food and Nutritional Sciences, The University of Reading, RG6 6AP Reading, UK.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Gordon
mesh_terms: D000485:Allergens; D001252:Astringents; D002392:Catechin; D005511:Food Handling / Q000379:methods*; D005780:Gelatin; D007782:Lactoglobulins / Q000737:chemistry; D010047:Ovalbumin; D013634:Tannins / Q000737:chemistry; D013649:Taste; D000067796:Whey; D000067816:Whey Proteins; D014920:Wine / Q000032:analysis*
chemical_list: D000485:Allergens; D001252:Astringents; D007782:Lactoglobulins; D013634:Tannins; D000067816:Whey Proteins; D002392:Catechin; D005780:Gelatin; D010047:Ovalbumin
keywords: Astringency; Fluorescence; Gelatin; ITC; Tannins; Wine; β-Lactoglobulin