Category Archives: enology

Introducing the Wine Recipe Wizard

Introducing Washington Winemaker’s new Wine Recipe Wizard! This is a more robust version of a spreadsheet I’ve been using to create wine recipes. Use it to go from juice to must by adding sugar, water, and acid. The Wizard is designed to tell you exactly how much of each – all you need to do is tell it about your juice (specific gravity, titratable acidity, and volume) and what you want the must to be like (specific gravity and titratable acidity).

This is how I make rhubarb wine, apple wine, raspberry wine, cherry wine, and others. Juice, measure, adjust, then ferment. The Wizard helps with the “adjust” step.

Give it a try – Give me some feedback

I’m not sure there’s a first version of anything that’s perfect, and I don’t expect this to be an exception. There are ways to make it better, and I don’t know all of them. So if you think of one, let me know. I wanted to get it out quickly – for Rachel, Paul, and everyone else who’s been waiting for me to do this – and that meant leaving some unfinished business:

Known Issues

  • You have to enter the volume in liters, and this probably isn’t ideal for US users. I plan to add a radio button that allows you to select US or metric units, but in the meantime remember that 1 gallon = 3.785 liters.
  • You can only use sugar syrup with a specific gravity of 1.310. Another radio button will be coming soon that will allow honey or custom values.
  • The Wizard doesn’t handle juices that are sweeter and more acidic than the must. So if your juice SG is higher than the must SG and your juice TA is higher than your must TA, you will get an error message.
  • There are some limits on what values you can enter, but it will still allow you to specify a must that is impossible to create with a standard sugar syrup. In cases like that the Wizard will tell you to add negative volumes of stuff – you won’t run into this for real world juices and ordinary musts, but it’s a bug that is in there and I do plan to fix it.

I’m excited about this, I’ll keep working on it, and I hope it helps.

Acidity In Mead: Being rigorous with incomplete data

I talked about five of my meads yesterday, and how I might decide if they were ready to bottle. I looked at clarity and specific gravity (SG) because I didn’t want the mead throwing off sediment or fermenting in the bottle. I tasted, probably the most important test of any wine or mead, and I checked the acidity.

Mead’s peculiar chemistry makes it difficult to measure the titratable acidity (TA). I explain this in more detail here, but the short version is that the common tests, like titration, overstate the TA. That made me think that such tests had no value, but I’ve since changed my mind. Measured TA’s don’t give you a precise value, but they do give you some information. That’s why I reported TA values for all five meads yesterday.

Using titratable acidity values in making mead

What do those values tell us? I began to get an idea about that when I was thinking about my cherry mead. As I said back then, you can use the TA values as upper limits. If you want to make a mead with the acid profile of a white wine, for example, you look up the range of acid values common in white wine then aim for the high end of the range. A good book on winemaking basics will give you that information. I like Daniel Pambianchi’s Techniques in Home Winemaking, he covers the basics really well and has special sections on ice wine, port, and sparkling wine. He says that the TA in white wines will normally range from 5 – 7.5 g/L. Adjusting a mead to 7.5 g/L puts the actual TA somewhere below that. Tasting the adjusted mead, after about a month or so to allow any acid additions to integrate with the mead, will reveal if the acidity is too low. If it is, then a series of add (no more than 0.5 g/L) – wait – taste cycles will nudge it right into the sweet spot.

Trying to improve a good approach

This is a good approach, but I’d like to get better information on the lower limit of a mead’s TA. Since the measurement error stems from the gluconolactone that exists in equilibrium with gluconic acid and that equilibrium depends on temperature and pH, maybe careful measurement of TA, pH, and temperature would yield some information on how much gluconolactone got caught up in the measurement. We might be able to use that to get a lower limit on, or even pin down, the actual TA. I don’t know how to do that yet, but I’ll see if I can find out. Another way to tackle this problem is to find out how much gluconolactone typically exists in honey. Putting limits on gluconolactone concentration will allow us to put limits on the actual TA. Those are my ideas anyway, if anyone can shed some light on them, or has another idea, please leave a comment and let us all know.

Five Meads: Are we there yet?

I looked in on five meads yesterday to see if they were ready to bottle. I was looking for clarity, I tasted them to see if they were pleasant to drink, and I measured the specific gravity (SG), pH, and titratable acidity (TA).

Name SG pH TA (g/L)
2004 Plain Mead 1.001 3.05 5
2005 Apple Mead 0.995 3.39 5.2
2006 Experiment (boiled) 1.000 3.27 6
2006 Experiment (no heat) 1.000 3.29 5.3
2006 Grape Mead 1.000 3.51 5+

Ready or not, this four year old mead is going in a bottle

I tasted sweetness on the 2004 plain mead, despite the low SG. It had that distinctive, pleasant aroma that I’ve come to associate with mead, and the lady of the house thought it was, “a little young, but it’s going to be good.” I’m not sure I’m as patient as she is, so I’m going to bottle it.

This apple mead is the only one not ready to bottle

The 2005 apple mead tasted and smelled of apple, but only a hint. I thought it was a little tart. It was the only one of the lot that I thought wasn’t clear enough to bottle.

Trying to settle a long running debate

The 2006 experiment is a test of the idea that boiling a mead’s honey-water mixture before pitching the yeast impairs the aroma by driving off volatile compounds. I split a batch, boiled one and made the other without heating. That was two years ago, and I think these meads are ready to bottle. I normally age mead for three years though, so I may let them age in the bottle then have a tasting party next February.

Update 10/28/2008 – The results are in!
It was a long running experiment with a little surprise at the end. Follow this link to see the results of my mead boiling test.

The trouble with titration

The 2006 grape mead is made from the pomace of my smallest batch of wine ever. I added honey, water, nutrient, and cream of tartar. I had some trouble checking the TA on this one because I ran short of sodium hydroxide, the base I use to titrate acid in a wine sample. I added 5 ml to the sample, and that brought the pH to 7.4. That’s very close to the end point. If I really had reached the end point, it would have indicated a TA of 5 g/L. It’s a bit more, maybe 5.25 g/L, but since I can’t be sure I just noted “5+”

Hmm, that acid measuring contraption I wrote about the other day just looks better and better.

Titratable Acidity: A Better Way?

A man, his contraption, and a different way

I learned of a different way to test for titratable acidity, the other day. At the last meeting of the Puget Sound Amatuer Wine and Beer Makers club, Don Proctor demonstrated this method using an odd looking device. He used ordinary baking soda (sodium bicarbonate) to neutralize the acid in a test sample. The important thing about this chemical reaction is that it gives off carbon dioxide (CO2) in direct proportion to the amount of acid neutralized. Now his device didn’t look so odd. The stoppers, tubing, glass cylinders, and green liquid were used to measure the amount of CO2, and if you know how much wine was in your sample and how much CO2 was produced, you can find the acidity of your sample.

The difference is in what you measure

This method, and conventional titration, both aim to measure the amount of acid by neutralizing it with a base. In a titration, you add a carefully measured amount of base until all the acid is neutralized. It’s important that you add just enough base to neutralize all the acid – no more and no less – because you determine the amount of acid in the sample from the amount of base that you add. Because you have to measure the base so precisely, it’s best to add it in liquid form. That means you need to have a solution of base at a precise concentration. Now, this is easy to find, but it’s expensive and it has a short shelf life.

Why the new way is better

You need to neutralize all the acid in Mr Proctor’s method too, but you don’t need to know how much base it took to do that. That means you don’t need to determine the end point (no pH meter) and you can use cheap, shelf stable baking soda instead of expensive perishable sodium hydroxide. That’s a big plus, as I found out the last time I ran out of chemicals. I’m going to have to get one of these contraptions!

Update 9/8/2008: A picture is worth a thousand words

If you’re having trouble visualizing it, take a look at this photo.

Tomato Wine: Fermentation Complete

It looked like fermentation was winding down, so I drew a sample for testing. The sample had some dissolved CO2 in it, and that can skew my tests in two ways. It can give rise to carbonic acid, which will push the titratable acidity (TA) higher. It can also make it look like there is more sugar in the sample than there really is. As the CO2 comes out of solution, in the form of bubbles, it physically pushes upward on the hydrometer which leads to a higher specific gravity (SG) reading.

SG: 1.000, pH 3.03, TA: 10 g/L

The TA went from 6.5 to 10 g/L in six days, which is a much bigger jump than I was expecting. Did the carbonic acid push it up that much? Or did I just botch the test? Either way, the thing to do is rack and set it aside for a while. When I come back to retest, the CO2 will have bled off and I’ll have better results.

Mead From Cherries: So far, so good

Making mead from cherries

I’ve often thought about making “second wine” using honey instead of sugar. Also called “false wine,” it’s made from the pomace of newly fermented wine by adding water, sugar and acid. I like honey, water, and acid (mead) all by itself, so using honey instead of sugar should be an improvement. That’s the idea behind my cherry mead, which I made in 2006 and 2007 from the pomace of that year’s cherry wine.

A little adjustment and a little more time

I got a chance to look in on the 2007 cherry mead when I racked it the other day, and I think it’s coming along nicely. If I had to sum up the flavor in one word, it would be “mild.” It’s a little fruity, and the aroma is pleasant, but I think it needs more time. Here are the numbers:

Date: 11/21/07, Specific Gravity: 0.996, pH: 3.39, TA: 5 g/L

The TA is a little low, so I added about 1.25 g/L of tartaric acid. With that little adjustment, I’ll leave it alone to age for a while.

Red Wine From Cherries: Revisiting the acid problem

Making red wine from cherries

I made cherry wine, in June 2006 and 2007, like a red wine from grapes. I crushed the fruit, adjusted the sugar and acid, and pitched the yeast. The sugar and acid profile of cherries is very different from that of grapes, so “adjusting the sugar and acid” is a much bigger step in making cherry wine than it is in making red wine from grapes.

Acid: Fixing one problem will make another worse

I just racked the 2006 cherry wine, and that “bigger step” is proving to be a real headache. The pH is too high, which puts the wine at risk of spoiling, and the titratable acidity (TA) is too high, which leaves the wine tasting tart. I first noticed this problem a few months ago in my 2007 cherry wine, and decided to wait a while before acting. Ok it’s been a while, and I think I’ve just proven the old adage that ignoring a problem doesn’t make it go away! Here is an analysis of both wines:

Name Date SG pH TA (g/L)
2006 Cherry Wine 11/21/2007 1.010 3.83 9
2007 Cherry Wine 7/30/2007 1.007 3.76 11
2007 Cherry Wine 11/21/2007 1.006 3.90 7

Both wines finished off dry, and both suffer from high pH and high TA. I don’t have earlier data for the 2006, because I didn’t have a pH meter or an acid test kit when I made it, but the measured pH rose and the TA fell in the 2007 cherry wine. I’ll tackle the 2006 vintage first. The way I see it, I’ve got two options in dealing with these problems.

The simple option: Add acid and balance with sugar

Adding more acid will lower the pH. That will solve the first part of the problem and improve the wine’s stability. Neutralizing some of the existing acid will lower the TA, which will solve the second part of the problem and improve the wine’s flavor. Speaking of flavor, it isn’t very good. I don’t think I can describe it in any useful way, Marsha said it was “icky,” but it didn’t taste tart. I think that gives me some leeway to lower the pH by adding tartaric acid, even though the TA is already high.

The complicated option: Replace one kind of acid with another

The acid in my cherry wine is mostly malic. That’s different from grape wine, where the acid will be mostly tartaric. What if I could replace some of that malic acid with tartaric? That would make it more like a conventional grape wine, and might solve my twin acid problems. This would mean neutralizing some malic acid first, then adding tartaric acid. It turns out that neutralizing malic acid is tricky and it makes this option a lot more complicated than just adding tartaric acid and relying on residual sugar to balance it. My 2007 cherry wine has the same acid problem, so whichever option I choose, I’ve got a lot riding on the outcome.

Apple Wine Recipe: Surprising increase in acidity

I racked my apple wine on 11/15/07. It analyzed out as:

Specific Gravity (SG): 0.996, pH: 3.56, Titratable Acidity (TA): 7 g/L

So it had fermented out in less than ten days, but the thing that surprised me was the TA. It rose from 5.5 to 7 g/L when I was expecting it to drop. The wine has only just finished fermenting though, so its probably got quite a bit of carbon dioxide (CO2) dissolved in it. That CO2 will give rise to some carbonic acid and a higher TA. I honestly don’t know if that’s enough to explain the high acidity, but I’ll let it be for a while. As it ages, the CO2 will bleed off and I’ll test (and taste!) it again.

Calibrating A pH Meter: Maybe The New Buffer Solution Will Do

I racked and measured four batches the other day, and it gave me the opportunity to size up my new buffer solution. I recorded TA values for three of those batches while I was still using my old buffer solution to calibrate my pH meter, and they shouldn’t have changed much. Here are the data:

Name Old Buffer New Buffer
Rhubarb Wine 4/22/07: 6 g/L 11/10/07: 7 g/L
Oregano Wine 8/12/07: 6 g/L 11/10/07: 5.5 g/L
Grocery Store Chablis 8/23/07: 7 g/L 11/10/07: 6 g/L

The old and new measurements are all within 1 g/L. Since I’m measuring my liquid volumes with the plastic syringe that came with my cheap acid test kit, not pipettes or burettes, I don’t think I can claim accuracy better than 1 g/L. So I’m not going to say the new buffer is great, but any error its causing is pretty small.

A Simple Mead Recipe: Acid and oak

How much acid?

I looked in on my mead the other day. It was clearing and had thrown some sediment. It was dry, with a specific gravity of 0.996. The pH, at 3.39, was low enough to protect the mead, but the titratable acidity was only 3.5 g/L. Titration will overstate the amount of acid in mead, so that 3.5 g/L figure is really an upper limit. Still, it’s better to have incomplete data than no data. If I were aiming for 7 g/L, that would mean adding 3.5 g/L. I don’t think I want to (more than) double the acid all at once, so I decided to at about 1.3 g/L, which should raise the TA to 4.8 g/L. How did I come up with 1.3 g/L? It just so happens to be 1 tsp/Gallon, which I have found, by tasting, to improve lifeless meads. I’ll test, and taste, again later to see if it needs more.

How much oak?

I decided to oak this batch of mead, and for me that means adding oak chips. I’ve been curious about barrels, but I don’t think they’re worth the trouble and expense. I’ve found that 1 g/L of oak chips adds enough character to white wines without overpowering them. For this batch of mead, I’ll actually use about 1.3 g/L. There’s that magic number again.

Oak on the scale

It turns out that the smallest increment that my kitchen scale will measure is 25 grams, and 25 grams in 5 gallons (19 liters) is about 1.3 g/L.

Toasting the oak

Whether it’s in the form of barrels or chips, oak is usually toasted before it’s used in winemaking. Barrels may be toasted by an open flame, but I’ll put my oak chips in the oven and broil at 400F (204C) for 45 minutes.

Toasted oak chips

Here’s how they look when they’re done. The oak chips in the casserole, on the right, were toasted. The ones on the left were not.

Now we wait some more

I added the 25g of toasted oak chips to a new sanitized carboy. Then I dissolved 25g of tartaric acid, and added that to the carboy. After I siphoned the mead off it’s sediment and into the new carboy, it looked like this.

Oak in the mead

You can see the oak chips floating on top in the neck of the carboy. In time, they’ll sink to the bottom. Oak chips are normally left in wine or mead for a few weeks, but I prefer to use a smaller amount and leave them in for a long time – six months to a year. This way, I’m more fully extracting the flavor and tannin from the oak. After that, I’ll test and taste to see if it needs more acid, then rack off the oak.