Le Boise

[Bitter_Brew]

Hi all,

New here, just posted my intro in the welcome section.

While I was doing some reading recently about whisky, I came in a round about way to discovering "le boise".

Boise, if you are not familiar with it, is an additive to cognac and brandy to "correct" the tannins and maintain consistent flavour profiles (where "correct" probably means to reduce the production cost by allowing the use of less new French oak barrels). Strangely, there is only one post that I have found on this forum from back in 2005 where the guy who seemed most familiar with it wouldn't say much due to an NDA.

From this reference (https://morganthorpe.com/wp-content/upl ... addins.pdf), I have discovered that it is created by heating French oak chips in water at around 95 deg C (but less than 100) for about 7 hours. The chips are generally pre-baked in an oven ("Depending on the heating gradient generally ranging from 160°C to more than 200°C, the spectrum aromatic changes. At 160°C spicy notes predominate, at 180°C we obtain
warm notes of chocolate, vanilla, caramel, from 200°C the notes of coffee, roasting become significant."). It appears that you then mix this in equal parts with spirit at around 50%, leave it for at least a month, then dose at something around 2-4%.

I have also read that it can be achieved by soaking wood chips or shavings in a lower alcohol spirit and sugar mix for an extended period, but I haven't found any specific details.

I have found a few other posts about "wood tea" etc but nothing of real significance.

Anyone experimented with this?

Bitter

[contrahead]

Anyone experimented with this?

Well it looks as if no one is going to respond to your thread. Not too many of us parlez français either. A quick answer would be no; not exactly. But yes in a roundabout way.

People here do roast sticks of wood to different stages of “char” - which is similar. Others have taken chips and shavings of used whiskey barrels (bags these are sold with the intention of making barbecue smoke) and placed them in jars with white spirit, which is all then microwaved. This trick works as an experiment and does flavor the spirit; but the process is inefficient and releases ketones, oils and other crap that was entrapped in the wood during the first bourbon run.

[Demy]

I tried experimental to heat my wooden sticks (toasted in the oven myself) with water or alcohol (wood tea in short) ... I have obtained flavor but also many tannins that give astringent flavor to the distillate.

[Bitter_Brew]

Well it looks as if no one is going to respond to your thread. Not too many of us parlez français either. A quick answer would be no; not exactly. But yes in a roundabout way.

People here do roast sticks of wood to different stages of “char” - which is similar. Others have taken chips and shavings of used whiskey barrels (bags these are sold with the intention of making barbecue smoke) and placed them in jars with white spirit, which is all then microwaved. This trick works as an experiment and does flavor the spirit; but the process is inefficient and releases ketones, oils and other crap that was entrapped in the wood during the first bourbon run.

Maybe I should have put it in research; I wasn't sure where it would get more interest. Thanks for being the first respondent (and I find Google translate works wonders these days for most things, with a bit of care. I still get a laugh from the time long ago that Google translate told me that the amaro recipe I was translating needed a bunch of wild homosexuals).

Certainly there's plenty of information around on toasting wood at different temperatures but most of the experiments (microwaves, dildos etc) seem to have focused on using spirit to extract flavours, or boiling, and it's the extraction part that I was more interested in.

I think the problem with using spirits to extract them would be that you get a different profile to the use of water, and microwaving is almost certainly going to boil the mixture - which seems to be a no-no (although the reasons why are not so clear). With the profusion of reasonably priced sous vide machines these days I was hoping that someone would've tried an extended stew below boiling point.

I tried experimental to heat my wooden sticks (toasted in the oven myself) with water or alcohol (wood tea in short) ... I have obtained flavor but also many tannins that give astringent flavor to the distillate.

I'm assuming you extracted it by boiling them in water? In wine, tannin decreases over time and from my brief reading it appears that this is primarily due to reactions with polysaccharides and proteins in the wine. I have no idea whatsoever on what the difference in concentration of these molecules are from wine to, for example, brandy. I'm assuming that these don't get carried over in significant amounts. On the other hand, it seems that tannins may react with other congeners (aldehydes, fusel alcohol) that are carried over in significant quantities. So maybe two years of aging would sort it all out and give a better result than just two years on wood.

[NZChris]

I've had the technology to do this for years, but I'd never heard of it. I'll add it to my list.

Thanks for the 'heads up'.

[HDNB]

i've been using oak teas for years. it started off accidentally, where i had been aging on some sticks and forgot the last number of liters in the bottom of a SS barrel. there was actually more wood than booze.... about a year later it was like syrup. it was far too woody to enjoy in cup, so i thought i'll put a little bit in each aging batch to create a more uniform flavour profile and jump start the whole aging process.

either i've gotten better at making booze, or it does work very well. I've taken to keeping a quantity of both malt barley and malt rye in about a 1:1 (that is, rye:wood and the barley: wood in another vessel. not mixing rye/barley) mix with toasted, charred, cubed up ex-barrel staves. mixing about 1 oz to 1 gallon new make at the start of aging.

i would highly recommend, my experiences with jump-starting and making a more unified consistent whiskey have all been positive.

[Archee72]

Maybe I should have put it in research; I wasn't sure where it would get more interest. Thanks for being the first respondent (and I find Google translate works wonders these days for most things, with a bit of care. I still get a laugh from the time long ago that Google translate told me that the amaro recipe I was translating needed a bunch of wild homosexuals).

Certainly there's plenty of information around on toasting wood at different temperatures but most of the experiments (microwaves, dildos etc) seem to have focused on using spirit to extract flavours, or boiling, and it's the extraction part that I was more interested in.

I think the google translate has let you down again!

[Bitter_Brew]

i've been using oak teas for years. it started off accidentally, where i had been aging on some sticks and forgot the last number of liters in the bottom of a SS barrel. there was actually more wood than booze.... about a year later it was like syrup. it was far too woody to enjoy in cup, so i thought i'll put a little bit in each aging batch to create a more uniform flavour profile and jump start the whole aging process.

either i've gotten better at making booze, or it does work very well. I've taken to keeping a quantity of both malt barley and malt rye in about a 1:1 (that is, rye:wood and the barley: wood in another vessel. not mixing rye/barley) mix with toasted, charred, cubed up ex-barrel staves. mixing about 1 oz to 1 gallon new make at the start of aging.

i would highly recommend, my experiences with jump-starting and making a more unified consistent whiskey have all been positive.

Thanks for the info. What ABV are you using? Do you leave them in for a set period of time before removing the wood or indefinitely in a sort of solera mix?

I've had the technology to do this for years, but I'd never heard of it. I'll add it to my list.

Thanks for the 'heads up'.

Let me know how you go.

I think the google translate has let you down again!

I don't think so...

[HDNB]

well, i'm certainly no expert on the subject, as mentioned i just kind of stumbled into it.

The booze in the oak tea barrels is cask strength, maybe pushing 70%. and yes, i just add more booze and more wood. not much left in the cubes after years soaking, but ive only started over again once from scratch and that was only because there was just too many in there.

i did switch to used wood barrels because the Stainless on is needed elsewhere, and them bastards are over 1000 bux now.

[Archee72]

I think the google translate has let you down again!

I don't think so...

He he

[NormandieStill]

I speak French and can help with translating anything you need, but be warned that stuff like this is often passed on orally, not written down on the interwebs. I'm still planning on taking a tour at one of the Calvados distilleries. If I remember to ask (and the guide seems worth asking) I'll see if they use boisé at all.

I seem to recall some references to boisé (note the accent! ) in this thread.

In turn this referenced a thread on the straightbourbon site which discussed slow proofing and in which Nancy touched upon boisé (her description doesn't match yours though and is more in line with what I would expect from French distilleries). Even if it's not exactly what you're looking for I strongly recommend reading the entire thread through, specifically Nancy's posts. There's so much to learn in there that you won't get all of it in one go.

[Bitter_Brew]

I speak French and can help with translating anything you need, but be warned that stuff like this is often passed on orally, not written down on the interwebs. I'm still planning on taking a tour at one of the Calvados distilleries. If I remember to ask (and the guide seems worth asking) I'll see if they use boisé at all.

I seem to recall some references to boisé (note the accent! ) in this thread.

In turn this referenced a thread on the straightbourbon site which discussed slow proofing and in which Nancy touched upon boisé (her description doesn't match yours though and is more in line with what I would expect from French distilleries). Even if it's not exactly what you're looking for I strongly recommend reading the entire thread through, specifically Nancy's posts. There's so much to learn in there that you won't get all of it in one go.

Sorry for the slow reply; forum seemed to be down whenever I had a chance to log on.

Thanks for the links, and apologies for my lack of accent on "boisé". I was too lazy to look up the alt-key for it but now I can copy-paste it...

I expect a lot of this stuff is basically "trade secrets", but it seems like putting sweet water in a barrel with wood chips is the most well-known method. I am really curious on some of the other methods though, so I'll probably try the "boil to syrup" method and maybe throw some in the pressure cooker. Unfortunately I don't have a sous vide (yet). I've got a brandy to run in a week or two so I'll probably try to get some tails/sweet water from that for the "standard" method. French oak is ludicrously expensive around here in the brew shops, and I haven't found anywhere that sells it as timber (and they don't grow here), so I might have to do the experimentation with American oak (which apparently is quite chemically different).

I did a deep-dive on the chemistry of wood, and I've read a lot of papers. Lots on toasting levels (5-methyl furfural, vanillin etc), quite a lot on different oak types, surprisingly little on the variability of extraction of tannins, lignin, polysaccharides and oligosaccharides (from toasted hemicellulose). Most of it paywalled. Looks like I need to go to the library and use one of their subscriptions for further research.

Looking forward to seeing what you get out of the guide at the Calvados distillery. It seems a bit of a thing where some people are madly anti-boisé, and some are proud of it.

[OtisT]

I just read an article on Boise that was very light on details but one thing new I picked up was that the additive was a tar like substance. This makes me thing that after boiling the wood, the water is evaporated off, reducing the tea further until only a tar like substance is left. That process is just speculation on my part. I really like the smell of that sticky stuff that oozes out of a barrel when aging spirits a long time. I wonder if Boise is similar that that?

I guess this is something I will have to try in the future. It sounds like an interesting way to jump start aging. On occasion I do soak new make in a jar with a fair amount of new toasted oak before pouring that spirit into a Badmo barrel for long term aging. It definitely give a darker/richer spirit that over the barrel alone.

[NormandieStill]

I have a bottle of oak tea now. In an attempt to strip some of the flavour from some oak for use in ageing apple brandy I've been soaking it in neutral and then changing out the neutral every couple of months. The resulting blend tastes amazing... right up until the final aftertaste which is pure, unadulterated tannin!