Helping along ML in cold weather

This has probably come up before, but I wanted to see what others here do (if anything) to encourage ML to complete in their barrels when the temperatures are as cold as they’ve been lately. The places I work with are quite small and don’t have access to warm rooms, etc. Thought about tarping over groups of barrels with space heaters below the tarps, which I’ve certainly seen done at a number of places, but there’s been some concern about that being a potential fire hazard. I’ve seen people run fish tank heaters into individual barrels too, but I’m not sure that’s the best idea either.

Any other good low-tech ideas for helping ML to move along?

Take a chill pill and wait for spring!

Tell that to Sasha!

Probably all you can do, is dose it hard with a prepared ML Culture, but my guess is it won’t help too much.

We use EnoFerm Alpha , and it helps us be complete with the secondary fermentation before it gets cold.

I once laid electric blankets over some barrels to get primary to finish. Now, I have learned some patience and just wait for warmer weather.

I’ve rented a reefer container and worked with the vendor to put some electric heaters in it. I’ve found it can keep the temp constant at pretty much whatever you want with some fine-tuning. Mine have been outside, even, during this frosty weather.

Whether or not that will actually get your MLs to go is another (and sometimes unrelated, it seems) question.

If you like, PM me and I can give you the contact info of the guy I’ve worked with. It’s actually been shocking to me how cheap it is.

Thanks for the suggestions. Most likely we’ll just wait until the weather warms up as Hank suggested. Other options seem like they may be more trouble than they’re worth in our case.

Nate, I’m working with a couple of small urban wineries that are already crowded into very limited spaces, so there’s no room for a heated container even if we wanted to use one - plus I have to wonder whether it would be cost-effective to do that for the relatively few barrels we’re still trying to get to go through ML.


The tradition among biodynamic winemakers is to spoon the barrel overnight and keep it warm with your love…

The custom, top of the line SCM method is to create a tent with tarps down to the floor and put some heaters underneath there. You can create some pretty good heat in a small amount of space and really push malics through… I like to break it down once a week to stir, clean and cross-inoculate. And it makes your winery look oh-so-professional. But it’ll work in a pinch.


I like Ian’s idea and do something similar if there is no warm room available at our facility.
If you just wait, I’d stay on top of the VA tests and topping.
Best, Jim

Yes, no question about topping frequently. I’ve mentioned the tenting option - it’s always seemed like it’s worth a try to me - but we haven’t done it for barrels for various reasons, extremely limited space being one of them. We did do it with limited success to heat up a couple of macrobin fermentations though. Might have to try hugging those barrels…

I only have two barrels in a 55 F cellar. But a 100W light bulb under each, with blankets covering the barrels kept the wine around 63F, and the MLF finished a couple of weeks ago.

one thing I’ve learned is that if you do put the bbls into a significantly warmer environment - don’t top them right beforehand. It’s a huge mess. Wait a few days for them to acclimate/expand.

I have no doubt about that. I try to check the weather report any time I’m topping up barrels but there have been one or two times I’ve been caught off-guard by a hot spell coming a few days afterwards and that’s been a mess.

I ran paper chromatography tests late last month and it looked like all but three barrels had gone through - surprised me with the cold weather we had in January. Will probably retest the barrels next week - hoping the warmer weather we’ve been having this week will have pushed everything through by now. Would be good to get a little SO2 in them.

Why? Do they need some?

Helps me sleep better [basic-smile.gif]

It’s the standard procedure for us to add some after ML is finished, and we don’t add a lot even then. But with a lot of these barrels being Pinot Noir, I’d be concerned about letting them go too long with no SO2. Of course with Syrah and some other varieties it’s not as big an issue, especially if the pH is low. While I know that you and some other producers don’t add any SO2 prior to getting wine ready for bottling, I’m not sure I know anyone who does that with Pinot - always been my experience that it’s more prone to oxidation than most other varieties.

BTW, I opened a bottle of your 2011 White as a “mystery wine” during lunch at a bottling session last week - everyone liked it quite a bit, though not surprisingly no one came very close to guessing what it was! [cheers.gif]