Saturday, April 28, 2018

This one's for CL

Q. We have some white oak lumber that has been air drying for about a year as we do not need it. I noticed that it seems to smell more like vanilla than the acid oak smell. Is this possible?
A. You have discovered one of the secrets about drying white oak for wine barrels. The oak aroma does indeed become more a vanilla smell. The wood imparts this aroma to any liquids stored inside the barrel, especially wine, adding bouquet to the wine. I was amazed when I tasted wine from a fresh oak barrel versus wine from a barrel made with aged wood. This concept has been well known in Europe. This new aroma seems to be encouraged by exposure to rain.
Gene Wengert, “The Wood Doctor” has been training people in efficient use of wood for 35 years. He is extension specialist emeritus at the University of Wisconsin-Madison.
That's not much of an article, but it is about white oak and it is related to Wisconsin.

24 comments:

chickelit said...

I’m still a bit confused by the fact that some barrels are charred on the inside and some apparently are not. I have a small 1 liter charred (on the inside) white oak cask which I filled with 120 proof grain alcohol 3 months ago. I intend to bottle 750 mL of it next week as “barrel strength” whiskey and take it on a camping trip to Death Valley and share. The cask is supposed to be useful for several rounds before it wears out. This mimics the commercial production of whiskies except for the fact that most all are further diluted to about 80 proof.

As for white oak and wine, I’m not sure whether the barrels are charred on the inside before filling. You might recall that I mentioned getting some white oak from the lumberyard, making some shavings, and putting them in contact with alcohol - in this case 80 proof vodka. Sure enough, after a short period of time, I had a small batch of Sixty’s favorite perfume, Eau du Oak. The ethanol extracts volatiles and other organics from the wood. I intend to dilute the sample down to wine strength proof — around 12 proof and use it as a teaching tool for “what is an oaky chard.”

The Romans discovered that burning sulfur inside their amphora coated it with SO2 which - when combined with water, made sulfite - or a chemical equivalent. Sulfite acts as an O2 scavenger and prevents wine from going all the way to vinegar. Not sure how that plays into taste. Sulfite salts are tasteless but SO2 certainly is not.

chickelit said...

Chip might object to whether the Roman actually discovered the sulfite process - they probably stole it from the Egyptians. The Egyptians invented the earliest chemical processes and were of course masters at preservation.

chickelit said...

How long does it take to dry white oak? In the experiment I described above, I used new white oak from the lumberyard. Not sure how aged it is. It might be interesting to test whether another batch of Eau du Oak made with aged oak has more vanilla notes.

deborah said...

Serious chemist at work :)

chickelit said...

By the way, I like the name “Eau du Oak” better than the full-on French “Eau du chêne“ because that latter sounds like Eau du Dog or Eu du Chaney.”

Pardon my French

chickelit said...

I wish Palladian were still here to add his $0.02

Sixty Grit said...

I like the fact that your experiment with oak chips paid off. Did the Swiss have anything to do with charring?

So when is the meet-up in Death Valley? That is one of my favorite places in the west.

chickelit said...

Sixty, there’s an institution attached to the UW-Madison called “Forest Products Laboratory”. I betcha that prof was affiliated.

chickelit said...

I’ve never been to Death Valey, but we’re going with experienced visitors with a 4-wheeler Jeep. Should be fun.

chickelit said...

The charring was probably discovered by accident - it would have been an early method for sterilizing the wood and acts like an anti-fungal. High strength alcohol is its own anti-septic, but lower strength brews which were also also stored in oak probably needed a good cleansing once and a while. BTW, the tasty charred oak derivatives are OK to ingest but should never be inhaled — they are essentially creosotes.

ricpic said...

That White Oak pictured is thinking, "Oy, one more leaf and I'll plotz."

Chick - was Palladian a wine expert? I remember he had an appreciation for the finer things. There's a word for that that I can't think of. I miss him too.

chickelit said...

Riicpic, Palladian was an artist and an amateur chemist. I say amateur because I don’t think he had a degree in chemistry but he had an extensive working knowledge of what was what in flavor chemistry — way beyond what I know. He also collected samples of pigments and perfume ingredients.

Sixty Grit said...

There is an old rule of thumb about air drying wood - that is it takes one year per inch of thickness to dry wood from green to usable. As with most things in the wood working world, there is some truth to that, but there are way too many variables for that to always be true - species of wood, relative humidity, air flow over the wood stack, and many other things.

Testing the moisture content of wood involves drying a sample with a known volume in an oven and periodically weighing it. When it stops losing weight it is dry, and it is also too dry to be used in a product. So you refer to your notes and figure out when it was at about 6-7% MC. That is a good level for something that will be used indoors.

I have a two pin moisture meter that measures the electrical resistance of a piece of wood - it is close enough for my purposes. Once a piece is below 10% MC I can finish it and know that it won't fail.

I am going to guess that the piece of white oak you purchased was kiln dried and probably somewhere below 10% MC when you bought it. Being in SoCal it will stay dry with few opportunities to regain moisture from the atmosphere.

I air dry my lumber and given how hot it gets here in the summer that works well for me. The benefits are that the wood retains its natural colors and aroma - and as the Frenchies know, every tree is different. Some white oak is just outstanding. And for the record, most red oak smells rotten due to bacterial infections.

Sixty Grit said...

I mountain biked all over Death Valley in the winter. It was only 85 degrees during the day. If I could get my scanner to work I would post some pictures - it is a beautiful place. Just don't go during the summer. I learned that the hard way.

And being mostly anosmic I am thankful that I miss the Eau de Chien that permeates my dwelling.

I used to read the Sawing and Drying forum at Woodweb, that's where I read a lot of Doc Wengert's writing. He knows his stuff, having been around the world of wood for decades.

Sixty Grit said...

LOL at ricpic - I can imagine that tree thinking that.

chickelit said...

Sixty, going next weekend to DV, I just checked the temp and it’s currently 63 F. Borrego Springs is 82 right now (noon PST)

Sixty Grit said...

Excellent timing. Have a great time, take plenty of pictures. As I have mentioned here before, since there is not a lot of greenery around the geology is right there on the surface for all to see. It is an amazing place.

chickelit said...

Is there such a thing as a black oak? Is it confined to Arkansas?

Sixty Grit said...

You set them up, I knock them down.

The real answer. A search for "black" returns five hits, including some species in your general area.

The Jim Dandy answer.

MamaM said...

Looks like there might be a Jim Dandy of a burl on that tree, waiting for some wood doctor to later excise.

Sixty Grit said...

You noticed that too, eh? Heh heh...

chickelit said...

Are burls "tree tumors"?

Sixty Grit said...

Here is a brief overview of burls.

ken in tx said...

You can eat the acorns of white oak trees. You have to boil them to get the tannin out, its very bitter. They are not very tasty but make good survival food if you ever need it.