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10 Common Wine Additives

        Lifestyle | Wine Facts


Check the label of just about any wine in the United States, and you will find the words, "Contains Sulfites." Sulfites kill bacteria and undesirable yeast (more on that in a moment!) and help to preserve wine by protecting it from oxidation. All wines contain at least some level of sulfites, which are a naturally occurring compound found in grapes and other foods. The warning on the label is added for the benefit of those with a sulfite allergy or sensitivity.

Sulfites are used to sanitize equipment and may be added at any of several different points in the winemaking process including the following:

  • Harvesting -- when grapes may be sprinkled with sulfites before they are brought to the winery.
  • Crushing -- where sulfites prevent the grapes from fermenting with naturally occurring yeasts.
  • Fermentation -- to stop the fermentation process at a desired point.
  • Bottling -- to extend the wine's shelf life by preventing it from interacting with oxygen.