By Dan Mouer

When the Wine Wakes Up

By now there’s little doubt left that it is spring. Winemakers who have been at it for a while are aware of a couple of phenomena that occur in their bulk storage containers at this time of the year. The wine, seemingly having been in hibernation through the winter, appears to “wake up.” Some like to romantically think this is a reminder that wine is, indeed, a living product. Among the signs that the wine is awake are: a renewal of bubbling in the fermentation lock, perhaps increased cloudiness in a wine that had been nearly clear, and the rising of wine into the fermentation lock.

Each of these can represent nothing more mysterious than the warming of the wine as ambient temperatures increase slightly. Carbon dioxide that had remained in solution in the cool wine now bubbles out. The currents of convection within the wine stir up the lees that had fallen over the winter, and the warmth increases the wine’s volume, causing it to overflow into the lock.

None of this is particularly “mysterious,” and none of it necessarily deals with the “living” qualities of wine. These are strictly physical reactions to the arrival of warmer weather. However, it is possible that these signs might have to do with organic, rather than physical, processes. At this time of year I like to pull the locks off my carboys and take a good sniff of the wine. Is there any funkiness? Signs of oxidation or spoilage? I also use my wine thief or turkey baser to withdraw a glassful. This I swirl around in good light. If cloudy, has the wine started showing any signs of discoloration, such as graying or browning? These could be indications of microbial attack or oxidation. When I swirl the wine, are there fine, foamy bubbles along the rim and edges of the glass? This might well be a sign that malolactic fermentation (ML) is underway.

If you have kept your SO₂ levels up, and kept your carboys topped up and your fermentation locks filled with fresh sanitizing solution, then spoilage and oxidation are unlikely. However, unless your SO₂ levels are pretty high, your wine may well be undergoing malolactic fermentation. ML is a perfectly natural part of the winemaking process, but, in some cases, we’d rather prevent it while, in others, we’d rather encourage it. Taste your wine and check your tasting notes against those you made in the fall or winter. Is the wine now rounder? Smoother? Less acidic? You are probably in the throes of ML! If your wine was already low in total acidity or high in ph, it should be monitored carefully. When you are rather certain that ML has completed (1-3 months after it begins or renews in the Spring, raise your SO₂ levels to at least 50 parts per million. If there is early evidence of spoilage (off aromas, funkiness, high volatile acidity, “mousiness,” bring SO₂ up to about 75 ppm for reds, 50-75 ppm for whites.

Check your carboys and fermentation locks frequently in the spring and early summer. Make certain that the wine level remains within an inch or two of the lock, and that the lock is freshly filled with metabisulfite solution. If you notice wine in the lock, clean the lock thoroughly and add fresh meta solution.

Make sure that your wines are not in a place that will become too warm as summer comes on. Wine in bulk storage—as in bottle storage—should remain as stable as possible with regard to temperature swings. Cooler is generally better than warmer, especially for white wines. But once you have cleaned and refilled your locks, topped up the carboys, and determined, for information’s sake, if your wines are undergoing malolactic fermentation, then just relax. It has a ways to go before it will be ready for bottling, and, as a living substance, it has to follow its own rhythms and seasons.

I notice that my Riesling from this past Fall is already brightly clear, full of apricot fruit flavors and aromas, and it is stable.. Time to bottle it! It may be time to rack many of the Fall’s wines and to bottle others. When racking and bottling chores are done with, grab a bottle of last year’s wine and enjoy it with your sweetheart or some friends. Don’t mess too much with the wine.

New Publication

Techniques in Home Winemaking: A Practical Guide to Making Chateau-Style Wines

Revised and Expanded Edition

By Daniel Pambianchi

Véhicule Press, 2002

Pambianchi is Technical Editor of Wine Maker Magazine. I have not seen the earlier edition of his book, but I have heard that many Canadian home winemakers cherish it. This new edition is one of the best books available with a focus on the scale of production found in typical home-based hobby wineries. There is lots of good information on using kits, concentrates, and sterilized musts as well as fresh fruit. The book is a compendium of techniques and technical information presented at a level and in a manner completely suitable for hobbyists. If you have made a few batches and consider yourself “hooked” into the hobby, by all means get hold of this book. It is way more useful than the old-fashioned books based on country-wine lore and more appropriate than the treatises aimed at small commercial wineries. I just finished reading it through the first time, and I know it will become a constant companion and reference for me.