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BOTTLING YOUR WINE
  • 10 MISTAKES
  • ABOUT SULFITES
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  • FINING AGENTS
  • GRAPE VARIETIES
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  • FLOOR CORKERS
  • GLOSSARY
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    EVERYTHING YOU NEED TO KNOW ABOUT SULFITES
    Preservatives are an important part of wine making. Don't worry that adding them to your home-made wine. Not only do they keep wine from developing infections, they also keep the wine from oxidizing. If you are concerned about the use of sulfites in wine read on!
    Preservatives are an important part of wine making. Don't worry that adding 'preservatives' to your home-made wine. The thing we most often recommend is sulfite, and it occurs naturally in small amounts during fermentation. Sulfites are your friend. Not only do they keep wine from developing infections like fiIm yeast, mould, and acetobacter (vinegar bacteria), they also keep the wine from oxidizing. Without the use of sulfites you have to be terrifically careful to keep all of your equipment very sanitary and you still have to drink your wine up as quickly as possible before it spoils.
    Many people worry that they may be allergic to sulfites. True sulfite allergies are very rare. It's more likely that they have been exposed to a high level of sulfites in the past. In the 1970's restaurants would douse their salad bars with 2000 PPM (part per million) sulfite solutions in order to keep the produce fresh. Mixing this with acidic foods, such as salad dressings or vinegar, would cause the salad to release clouds of sulfite gas, provoking unpleasant reactions. 
    What most people describe as a sulfite headache is a reaction to bio-amines. These are compounds formed in wines for various reasons, one of the commonest being malolactic fermentation in the presence of sugar. Some commercial wineries start malolactic inoculation before the end of alcohol fermentation, guaranteeing the formation of bio- amines. Since wine kits don't go through malolactic they do not form bio-amines, and consequently don't provoke allergic reactions. 
    People familiar with bread making, or who have knowledge of beer making will want to re-hydrate the yeast prior to pitching it. This contradicts our instructions, which direct you to sprinkle the yeast directly on top of the juice. Who are you going to believe? You can re-hydrate the yeast if you wish, but be aware that anything less than utterly strict adherence to proper re-hydration procedures will kill your yeast instead of helping it. There's a long scientific explanation for this, but it boils down to viability. Simply sprinkling the yeast on top of the must will give you a higher live cell count than re-hydrating in most cases, and will be far less trouble.
    Potassium Metabisulphite is a stable source of sulfite in winemaking. The use of sulfur compounds is not a recent innovation. The Dutch shipping companies popularized the use of sulfur in the 16th century by refusing to ship any wines not treated. They insisted on the use of sulfites because the treated wines were the only ones that survived a long sea voyage without spoiling.
    Sulfites work by releasing free sulfur dioxide, which inhibits yeast, mould and bacteria. It does this in two ways: one, it kills some of the organisms outright, and two, it blocks the surviving organisms ability to reproduce. If your winemaking equipment is physically clean and you've rinsed it with a sulfite solution, nothing will grow on it. 
    		 
    Sulfites are also added directly to wine after fermentation, to help prevent oxidation. Oxidation in wine follows the same pattern that you see in the cut edge of an apple-the wine turns brown and takes on a flat 'cardboard' taste. Sulfur binds with the oxygen in the wine and prevents this damage. 
    Some facts that might clear up any misunderstanding about sulfites: 
  • Sulfites are a recognized food additive. The federal government controls their use. .All commercially available wines contain sulfites, even those labeled 'Kosher' or 'Organic'. The legally allowable amount in British Columbia, where Brew King kits are made, is 70 PPM. 
  • Nearly all dried fruits and meats contain sulfites. Raisins, for instance, have up to 250 PPM. Frozen orange juice, bacon, dried noodles, all contain sulfite. 
  • The amount of sulfite provided in Brew King kits will result in a level of between 15 and 30 PPM in a finished wine. 
  • All grape-based wines produce sulfites naturally during fermentation, up to a level of about 1O PPM. Even with no addition of sulfites, wines will still contain them. 
  • This is not to say that sulfites are totally benign. People with asthma or emphysema should avoid inhaling sulfite powder or the gas that comes off the prepared solution. It can act as a bronchial constrictor, aggravating any breathing problems. Also , adding extra sulfites to wine is of no benefit, as it can spoi I the flavor, giving it a 'burnt match', smell. It's important to follow directions for sulfite additions. 
  • The upshot of sulfite use is this: without sulfites you'd have to be very careful to keep all of your equipment sanitary and you'd still have to drink your wine quickly, before it spoiled, probably within one or two months. 

    • A final, but very important consideration is that if your customer insists on leaving out the sulfite from their wine kit, they must also leave out the sorbate. Sulfite suppresses malolactic bacteria, but sorbate does not. Without any sulfite to prevent malolactic fermentation, the bacteria will convert the sorbate into hexadienol, producing a stupendously horrible aroma of composting geraniums and rotting trout.
    copyright 2004 J.R.Leverentz
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