Stuck fermentation?

[dlvc1007]

I think my fermentation has stuck. Though I'm not sure if that's the case because the same thing has happened on two separate batches of wine started two weeks apart. They both stopped at around 6% potential alcohol with two different yeasts, lavlin d47 and ec1118. I've used the later in the past and it's unbelievably rapid. The only thing I can think of is I keep the house at about 60 to reduce heating costs, but that doesn't sound likely. Beyond that I'm stumped. Any ideas?

 

[Clann]

I think that is a little cool for wine yeast but I have never used those yeasts.

 

[dlvc1007]

I think that is a little cool for wine yeast but I have never used those yeasts.

If that's the case, do you think raising the temperature will start it back up? Or will I also need to restart them?

 

[Zwetschgen]

I would agree that temperature is low. I have used both yeasts, they have always worked perfectly fine for me. I don't think you would need to repitch once you get the temperature up. Some things you may want to try (other than messing with the thermostat), is a box with a light bulb or Christmas lights, or setting it in the sun with a towel or blanket wrapped around it. They make heating pads and such but those also cost a fair bit of money. The only other thing I can think of is if you started with an extremely high specific gravity and you have reached the allowable alcohol content for these yeasts (which means your starting potential alcohol had to be between 18-24% so that's highly unlikely).
If you give the wine a good heated spot and it doesn't do anything after a few days, do the unthinkable and dilute it with some water, some times it just needs a little diluting to get back to the proper sugar/alcohol/pH/etc. level...

 

[YoungBerry]

or Christmas lights

Be careful with Christmas lights. A lot of the newer Christmas lights are LED, and will do nothing for heat (they are very pretty though, and are safe to leave on all year long, I use them for track lighting in my apartment, but they add zero heat, so they won't help in this case), and you have to be careful with older Christmas lights and watch to make sure that there are no frayed cords and that that nothing overheats and catches fire.

 

[truckjohn]

60F is definitely around the slowing down point for those yeasts... Fermentation will crawl if you hit the mid 50's.....

I personally might watch out for christmas lights .... Check out the symptoms of "Light struck wine"......

A potential option is to move your carboy to a place that is a bit warmer in the house - say against a basement wall that is surrounded by earth..... Maybe a kitchen or bathroom that has a heating vent in it.... Possibly indoors in a south-facing room to take advantage of the warming from the sun....

Another option is to find a heating pad and sit your jug on a rimmed metal cookie sheet on top of the heating pad... Turn it on low for 10-15 minutes and then turn it back off... Stir it up good and see where you stand...

It doesn't take much - It will run just fine at 65F.

Thanks

 

[dlvc1007]

Thanks guys. I've got my carboys placed right next to the vent and it's picked up noticeably.