Proteins in wine explained

Proteins are present in wine. The most common proteins include thaumatin-like proteins and chitinases and have a role in the formation of turbidity (haze)^[1] especially visible in white wine.^[2] The quantity of haze forming is dependent on the quantity of phenolics in the wine.^[3]

Some of those proteins are considered nuisance. Some of them are grape pathogenesis-related proteins.^[4] Those proteins have been identified by mass spectrometry and originate from grape, yeast, bacteria and fungi.^[5]

These proteins are unstable when submitted to heat, and can be removed by treatment using bentonite,^[6] a process that contributes to the clarification and stabilization of wine.

Proteins residues from proteinaceous fining agents such as gelatin or egg white can possibly be found in wine. Wheat gluten has also been tested,^[7] but there are health issues regarding its use because of gluten intolerance in some people.

See also

• Wine chemistry
• Protein adsorption in the food industry

Notes and References

1. Pocock . K. F. . Hayasaka . Y. . McCarthy . M. G. . Waters . E. J. . Thaumatin-like Proteins and Chitinases, the Haze-Forming Proteins of Wine, Accumulate during Ripening of Grape (Vitisvinifera) Berries and Drought Stress Does Not Affect the Final Levels per Berry at Maturity . 10.1021/jf9905626 . Journal of Agricultural and Food Chemistry . 48 . 5 . 1637–1643 . 2000 . 10820071.
2. Marangon . M. . Van Sluyter . S. C. . Neilson . K. A. . Chan . C. . Haynes . P. A. . Waters . E. J. . Falconer . R. J. . 10.1021/jf1038234 . Roles of Grape Thaumatin-like Protein and Chitinase in White Wine Haze Formation . Journal of Agricultural and Food Chemistry . 59 . 2 . 733–740 . 2011 . 21189017.
3. Siebert . K. J. . Effects of Protein−Polyphenol Interactions on Beverage Haze, Stabilization, and Analysis . 10.1021/jf980703o . Journal of Agricultural and Food Chemistry . 47 . 2 . 353–362 . 1999 . 10563900.
4. Waters . E. J. . Shirley . N. J. . Williams . P. J. . Nuisance Proteins of Wine Are Grape Pathogenesis-Related Proteins . 10.1021/jf9505584 . Journal of Agricultural and Food Chemistry . 44 . 3–5 . 1996 .
5. Kwon . S. W. . Profiling of Soluble Proteins in Wine by Nano-High-Performance Liquid Chromatography/Tandem Mass Spectrometry . 10.1021/jf048940g . Journal of Agricultural and Food Chemistry . 52 . 24 . 7258–7263 . 2004 . 15563204.
6. Heat-Unstable Proteins in Wine. I. Characterization and Removal by Bentonite Fining and Heat Treatment. Juinn-Chin. Hsu . David A.. Heatherbell. American Journal of Enology and Viticulture. 1987. 38 . 1. 11–16. 10.5344/ajev.1987.38.1.11. 12943855. free.
7. Marchal . R. . Marchal-Delahaut . L. . Lallement . A. . Jeandet . P. . Wheat Gluten Used as a Clarifying Agent of Red Wines . 10.1021/jf0105539 . Journal of Agricultural and Food Chemistry . 50 . 1 . 177–184 . 2002 . 11754564.