A few MLF, Fining and k-meta questions

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Apr 21, 2010
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I'm doing MLF for the first time on fresh juice Chilean Malbec, Syrah and Carmenere. All are in 5 gallon carboys.

1. I was wondering what people are using for MLF test kits and where to get them.

2. What is the amount per gallon of k-meta and is this the rate throughout the wine making process, or do so2 test kits determinr rate?

3. after adding fining agent, can I rack directly into bottles or should it be racked into another carboy for a period of time before bottling?

4. When should the last and final k-meta addition be added with fining agent in mind?

Thank you. To this point I made cab sauv, nebbiolo, and valpolicella last fall. I did not do MLF and started k-meta after first racking, but only at a rate of 1/4 tsp/5 gallon and then 1/8 tsp/5 gallon after last rack.
1. Paper chromatography kits are readily available from winemaking supply shops and are easy to use and quite reliable for determining MLF completion. Or if you cannot get a testing kit, you can just give the wine plenty of time to ensure MLF is complete and then hit it with a relatively high dose of SO2 and filter through 0.45 micron pads to remove as much of the bacteria as possible to prevent renewed MLF in bottle if there is residual malic acid left in the wine. This is pretty heavy-handed treatment, though, so I would recommend testing for MLF to avoid having to take this approach if not necessary.

2. SO2 should really be determined individually for each wine based on pH and then monitored and adjusted throughout aging and prior to bottling. However, plenty of home winemakers use a standardized addition of KMS to all of their wines and have had good success with this approach.

3. I would not add fining agents to red wine unless you run into a particular problem with haziness or harsh astringent tannins. The tannins in red wines will generally help clarify the wine well without the addition of fining agents and if you're making the wine from juice rather than grapes, the chance of having tannins that are too harsh is pretty slim.

4. Final adjustments to SO2 should be made just prior to bottling. I usually aim for about 15-20mg/l higher than my final desired SO2 level since some will be bound up during the bottling process.
didn't realize that i had to do mechanical filtration after mlf. is this a pressurize system or can the final racking be poured over these filter pads? thanks.
You do not want to pour wine over anything as that exposes it to way too much 02. You dont need to filter any wine but many do and I do sometimes also with a cheap gravity filter. Here is a picture of my cheap gravity filter and a link to where you can buy it. Wines must be clear before filtering a wine though or any filtration unit will clog during making this process a freakin nightmare where you will have to disassemble then unit during and maybe even a few times.

Wade E, what stage in wine making were you at when the photo was taken? Is thw wine gravity drop creating to much o2 mix? Thank you.
The pads Wade is using in that filter are nowhere near what is needed for a sterile filtering of .45 microns. That filter would just remove yeast cells not bacteria. To do that you need at least a .45 micron cartridge filter system and quite possibly a membrane filter would be better. Just get a test kit (chromatography) and be sure it is done. That way you don't need to filter if you aren't planning on sweetening.
To sterile filter will cost you quite a bit of money cause the unit to do so is pretty expensive and the filter and cartridge are al;so very expensive.

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