Hi Folks I have personally stuffed up approximately 90 litres of wine so far and I'm determined to get a better understanding of the process for the future. I am reading as much as I have time to but I keep reading info which is contradictory. I'm hoping the folks on here will share their hard won knowledge around Camden tablets.
At this point I think that the tablets are used for ensuring bacteria don't stuff up your juice before the yeast can do it's thing. I also think that the effect of the tablets will wear off, but how long that takes I don't know.
The tablets contain potassium metabisulifte, (K-meta, sulfite, KMS are common terms) and can also be purchased in powdered form (I find it easier as a powder) which has a couple of substantial uses in winemaking. Firstly, when mixed (3 TBS/Gallon) with water, it is a very effective sanitizer to be used in sanitizing anything that comes into contact with your wine. When mixed into wine at the rate of 1/4 tsp / gallon, it is also very effective at preventing any unwanted organisms from growing in your wine, as well as it's wonderful property of preventing oxidation of your wine.
Do I need to keep using them with each racking?
You do not need to apply sulfite every time you rack, only when the level of sulfite is too low to protect your wine. OK, I know, you don't know how to measure it. Have no fear, some use a "rule of thumb" which is 1/4 tsp per 6 gallons, every three months, which may be a tad of overkill, but is very safe. One day when you decide to own measuring equipment, you can be more precise, monitor your free sulfite, and adjust it based upon your wine pH, for now, use the rule of thumb, and don't rack every week. Once the gross lees are gone, racking every three months and updating your sulfite is sufficient.
Do they have another name? Will they effect flavor?
Yes, see above. In addition to potassium metabisulfite, there is also sodium metabisulfite, equally as effective at all of the things above, but is purported to alter the taste of your wine, so should only be used for sanitizing your tools. if you overdose with either of these products they will definitely affect flavor, so pay attention and stay focused, and keep records so you know when your last application was.
Do they kill yeast? Beneficial or otherwise?
Sulfites stun yeast more than they kill it, at least at normal dosage rates, particularly the yeasts that may come naturally on grapes or other fruit. The 1/4 tsp / 6 gallon dose that some folks use in their must, prior to fermentation, is meant to do just that, stun the native critters, then when cultured yeast is added 24 hours later (most cultured yeast is more tolerant of sulfites, by design) it easily takes over the job of fermentation.
