Aging, Sweetening, and Testing
It’s not too difficult to add a few more steps or a few more processes to turn your kit wine making into something wonderful.
Bulk age —We all know that wine improves with age,and one of the easiest changes to make to a 6–8 week wine kit is to allow it to age a little longer before bottling. Bulk aging means aging it while it’s still in carboys rather than in bottles. I now find that I bottle my kit whites in 3–6 months and my reds are more like 6–9 months.
There are things you should keep in mind if you’re going this route. As noted, potassium metabisulfite (SO2) is a stabilizing preservative used to protect the wine from the oxidation that happens naturally in aging and due to oxygen exposure. If you’re planning on aging for longer than recommended, the kit’s SO2 packet won’t be sufficient. Oxygen exposure and aging will dissipate the active SO2 protecting your wine, so you always have to watch this to ensure it doesn’t get depleted.
Tips to keep manage your SO2
- Headspace. One way to safeguard your wine is to have less than an inch of headspace between your wine and the bottom of your bung in the carboy. Less air = less oxidation and less need for SO2 addition.
- Test it. If you’re measuring SO2 already, then you’ll want to test your wine 6 weeks after adding the first packet. Use a sulfite calculator to understand the levels to add for your wine volume and pH level. If you or someone you’re sharing your wine with is sensitive to SO2, you’ll want to learn to measure SO2 and adjust it. EnoFile comes with an SO2 calculator built in, so if you know the current SO2 levels, it’ll tell you how much potassium metabisulfite to add to protect your finished wine.
- Adopt a formula. If you’re not measuring SO2, you can guesstimate the need for it with an additive regimen like the one I’ve used:
- 14-20 days after fermentation start — Add SO2 packet at recommended timing on the 6 gallon kit.
- 3 weeks after 1st addition — Stir 1/4 teaspoon of SO2 into 50 ml of cool water and mix into 6 gallons of wine. The original SO2 is likely close to depletion by now as you’re nearing the normal kit bottling date. This dose will bring the SO2 above the necessary level, but will allow you time to ignore your bulk wine in the cellar for a while.
- 4 months after start — Stir another 1/4 teaspoon of SO2 into 50 ml of water and add to 6 gallons of wine to bring the level back up.
- 8–9 months after start — At this point, I’m usually preparing to bottle. Prior to bottling, I add another 1/4 teaspoon, since I’ll be bulk aging in the bottle for likely another 6 months to 3 years.
Why does this formula work? For the first addition, oxygen levels are the highest and SO2 is depleted faster, so we add another addition after only 3 weeks. After that, it assumes SO2 is depleted at a rate of about 15 ppm per month for 6 gallons of wine stored at 65-75 degrees Fahrenheit. Each ¼ teaspoon addition should bring 6 gallons of white wine up by about 40 ppm. Testing will definitely be more accurate, but if all else fails, err on the side of adding more, rather than less as long as you don’t over add. Warning: Total SO2 can be detectable at 100 ppm and high levels will burn your nose!
If you’re back sweetening — that is, sweetening a dry wine — you’ll want to perform a bench trial and not just add the recommended amount of sugar. This is a well earned lesson from a limited edition Winexpert kit called Pacific Quartet that I made exactly to the instructions, including adding the entire packet of sweetener. Unfortunately, this made a wine too sweet for my palate! (Did I drink it? Yes. Reluctantly, mixing it into spritzers and giving it away to those who enjoy sweeter wines!)
With an identical kit, we decided to test different amounts of the flavor packet before adding. The math isn’t too complicated, but it does require thinking through totals and creating ratios that are similar.
On a 6 gallon kit, you’ll break down the trials into 6 glasses that contain 50 ml of the wine with different totals between 0–100% of the sweetener. You need a milliliter syringe for this experiment, that allows you to measure small, graduated amounts of sweetener.
For my trials, I set up 6 glasses to try and my husband and I privately write our favorites. When we don’t agree, I choose the difference between the two.
This is what trials on a 6 gallon batch with 1000 ml of sweetener looks like. The first column is the percentage of sweetener; the second shows how much wine should be in the glass; the third is how much of the sweetener solution you’ll put into the glass. Finally the last column shows how much of the sweetener to add to the 6 gallons of wine.
“Lees stirring ”— Some of the best Chardonnays are made better when they are aged “on the lees” (or French sur lie) and this can also be true for your kit wines. If the French terms scare you, take a deep breath and go with me because it’s worth it. White wines aged on the lees are creamier, richer, fuller-bodied or with a greater depth and complexity of flavor.
This is a no-waste operation. Instead of discarding the leftover yeast waste particles found in your primary fermentation, you keep them. These are the “lees.” You periodically stir them around in your wine using a baton – um, spoon – a process the French call “batonnage.” Winemakers use a process the French call batonnage in conjunction with bulk aging (normally in barrels). All they do is leave the fine lees (those left after you transfer the wine out of primary) in the wine and stir them into the wine over a period of 12 months.
But when you stir, you introduce oxygen which is generally undesirable when making wine. My recommendation is to stir it every day prior to stabilizing your wine. After the stabilizers, 2 times a week will work until the second SO2 addition. After you finish your batonnage routine, you can let the wine settle and proceed with racking normally in conjunction with bulk aging. Your own sur lies aging should impart some of the yeast characters that enhance flavor and aromas, but not affect the oxidation level of the wine.
Blend two finished wines — The reason to blend wines is get a better product.
We first tried a blend when a White Burgundy style was no longer available to us pre-blended in kit form. Instead, we made two batches of wine separately, a Sauvignon blanc and a Semillon/Chardonnay.
We set up a bench trial where we used different proportions of each. Starting with the middle with 100% of each, we mixed 50 ml of each together. Then we created a generalized 25% gradation of each, so the final blend looked like this:
Start testing! You’re likely already testing your brix or specific gravity because the kit instructions tell you to. But if you want to step it up, you’ll want to know where you’re starting and where you’re aiming. Not only do professionals understand the sugar content in their grapes, but they’re testing a whole volley of other things. If you’re just interested in testing more than brix/SG, then I would suggest buying a few things to get you started testing the pH, the Total acidity and the SO2.
|Equipment needed||What it tests|
|pH Meter||pH is a measure of the strength of the acid in your must or wine.|
|Acid test kit||Total acidity is a measure of the acid level of a wine. It’s usually balanced by the perceived sweetness in a wine (even when a wine is dry). Normally, must starts out higher in acidity, but acid may be converted during fermentation.|
|Sulfur Dioxide (SO2) testing kit||Sulfur Dioxide acts as an antioxidant and an inhibitor of microbial growth. It is measured in parts per million (ppm) and additions needed vary based on pH levels of wine.|
With our original kits, we didn’t test anything except temperature and specific gravity. But when we wanted to begin with our own fruit recipes, we realized we needed readings for pH and acid at the beginning of fermentation to make for a successful fermentation. In addition, after opening some year old white wines much darker than they were bottled, I realized that I needed to know exactly how much SO2 was in the bottle protecting our wine.
Being gadget people, we started out by purchasing the least expensive digital equipment we could afford, but these devices were not inexpensive. We first bought a Vinmetrica SC-100 to test SO2, a pH meter and a simple Titratable acidity test kit from our local brew store. This testing equipment cost about $150, but it’s been well worth it. pH testing is the easiest, as the meter is placed in a vial of wine and the device gives you the reading. SO2 and TA testing requires mixing multiple solutions and then measuring the amount of reactant you use to change the solution color. Each kit comes with good instructions, but require multiple steps and some math at the end. I suggest finding a how-to video on youtube to help walk through the process of whatever equipment you buy. However, in the end, you’ll feel like a chemist. All you have to do is buy a lab coat!
For those interested in stretching what they can do with wine kits even further, take a look at the suggestions also available in Stretching the Wine Making Kit: Advanced Techniques.