Campden Powder: Potassium MetaBisulfite

Almost all food-grade disinfectants can be used as a sanitizer. However, our favorites are Campden for winemaking and hydrogen peroxide. Refer to the link for 6 golden rules to sanitization

Phenolic: Spicy (clove, pepper), smoky, plastic, plastic adhesive strip, and/or medicinal (chlorophenols) like smells and flavors. German wheat beers and some English styles need these notes but often too much of a good thing is also bad. Another problem is that it can come from a variety of reasons, so debugging takes longer.

• The culprit to the root cause is the chlorinated water, which gives medical and bleach-like aromas.
• Second could be the yeast strains, try switching to a strain with a crispier finish. English stout yeasts are often attributed to clove flavors.
• The third is the sanitizer residue especially iodine and chlorine. Try switching to a rinse-free sanitizer.
• Fourth, mashing technique: Over sparging, using too hot water, or even crushing the grain too much can introduce these notes.
• Fifth and the most obvious reason could be adding excessive spices. Spices lead to an increased warmth perception (higher perceived ABV) which is why some winemakers deliberately add excessive cloves and whole spices (garam masala) in their wine.
• Lastly, in wine, this is called ‘Brett’ wine because of the yeast Brettanomyces strains (contamination) that were introduced in the vat.

Fruits contain acetobacter (bacteria that oxidizes ethanol alcohol into vinegar acetic acid), mold forming fungus, and several strains on wild microbes on their skin. You need potassium metabisulfite, Campden tablets or some form of sulfite to weaken or kill these bacteria before introducing the wine yeast.

Another alternative is boiling the fruit before adding yeast. However, the application of heat often leads to loss of most aromatic natural flavors and colors. Hence most winemakers prefer 12-24 hours Campden rest of their fruits to sanitize them and make a sterile medium for the wine yeast to dominate.

Another alternative is Sodium metabisulfite. However, you would need to use 20% extra dosage. This is because commercial sodium metabisulfite has much lower strength. Also, don’t use Sodium salts in the wine instead of Campden tablets/powder. It tends to alter the taste. Also, there are regulatory FSSAI norms to limit the salt content in food.

Campden a.k.a. potassium metabisulfite is an antioxidant/ preservative, commonly called “sulfites”. Most commercial wine labels will have listed it as one of its ingredients. It inhibits the bacteria activity but does not impact the yeast so much.

Potassium sorbate on the other hand is a preservative designed specifically to inhibit yeast reproduction. It’s used in white wine, cider, and mead which we want to be sweetened. Sorbate will prevent the yeast from fermenting off these residual sugars and prevent the wine from becoming dry and too alcoholic.

We recommend you to add 0.05gm of Campden powder per liter to achieve 25ppm of SO2 in your wine. Campden is added in dry red wines to prevent oxidation (turning to vinegar) and color stability (red color turning orange). I typically bottle wine at a pH of 3.5 and add about 25ppm of SO2 (from Campden) at the time of bottling. For other pH values, you can refer to the table below to compute the recommended dosage.

Add about 0.1 gm of Campden powder to fresh grape or apple or fruit juice to inhibit the bacteria, mold, and wild microbial activity in it. Cover the juice and let it rest overnight for the Campden to dissipate before adding any yeast and nutrients to it. This way the wild fermentation is prevented, and acetobacter, which turns alcohol into vinegar, is inhibited.

Wild yeast in fruit and grapes are often killed using Campden. However, once you have finished wine a stronger wine stabilizer is used when bottling sweet wine.

 A pH of 3.0 to 3.4. is desirable for white wines, while Red Wines have a pH range of 3.3 to 3.6. Your dry wine should have a higher pH, while your sweet wine typically is at the lower end of the range. This is because sweetness can mask a lot of sour/tartness or acidity.

If the pH is too low, the wine will taste like vinegar. If the pH is too high, then you would need an excess amount of Campden and preservatives to stabilize it. Remember Alcohol and pH are the two natural protection for wine.

Some professionals also measure TA (Total Acidity). It is essentially a measure of how much Calcium Carbonate is needed to increase the pH. The simple morality based calculations don’t work with beer with organic acids. There are a lot of biochemicals that can emit H+ ions but they are so weak that the pH meter does not capture it.

Campden tablets/powder are used as sanitizers and preservatives. They are sulfur-based and slowly release SO2 gases. It will be reminiscent of Diwali crackers because of this sulfur gas. Please don’t smell it or try to taste them (undiluted) as sanitizers are toxic chemicals.

Side-effects include headache and temporary loss of olfactory senses.

Also Called K-Meta or K₂S₂O₅ or potassium pyrosulfite is used as a preservative and sanitizer in wine making industry. It is a white crystalline powder with a pungent smell of Sulphur. This smell is because of SO2 being released. When in tablet form it is called Campden.

You can use either name as long as the potassium metabisulfite is stored in cool dry condition it will release SO2 that can be used as a wine sanitizer or to kill bacteria and wild yeast in the fresh grape juice.