Getting Wines Ready for the Winter Season
Most of you have either completed or close to completing fermenting your wines from this past harvest and now need to think about winterizing them.
Most whites will need to be stabilized while full-bodied Chardonnays and most reds will probably first benefit from malolactic fermentation (MLF) to reduce acidity, to enhance aroma and flavor profiles, and to stabilize against lactic acid bacteria.
If your winemaking area is already cold and will remain cold throughout the winter, you will want to wait until the spring before inoculating with a malolactic culture. In the meantime, you should sulfite the wine according to pH; just don’t make any other additions until after MLF as you need to keep free and total SO2 below the bacterium’s inhibition threshold — check the manufacturer’s specs. Use the Sulfite Calculator at http://www.winemakermag.com/guide/sulfite to help you guide your sulfite additions. And you’ll also want to take advantage of the colder weather to cold stabilize the wine and avoid tartrate crystals in the bottle later on.
And if your winemaking area is relatively warm, say above 18 ºC (65 ºF), then you can proceed with the MLF assuming the wine’s chemistry is fine. That means that pH is above 3.2 and free and total SO2 are within the bacterium’s specs. As for cold stabilization, you’ll probably have to look at transferring your wine into carboys that fit into your refrigerator, otherwise, unless you have tanks equipped with cooling jackets and a chilling system — highly unlikely in amateur winemaking — then you may not have much option but to leave the wine as is. You can add metatartaric acid but this is only recommended for wines not meant for aging.
In all cases, when the MLF is over, be sure to rack the wine and adjust the free SO2 level according to pH.
Other than that, there isn’t much else to do over the winter months but to look at bottling a past vintage or simply relaxing drinking wine without worries until the spring. Just be sure to taste all the wines at least once, if not twice, until then to make sure all is well.