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duffrecords
01-09-2013, 02:55 AM
I decided to make a bochet the other night so I boiled 11 lbs. of honey for 2.5 hours until it turned dark, dark brown (virtually black) then dissolved it in enough spring water to total 3 gallons. Specific gravity was 1.112 and pH was 3.4 so I assumed those were good starting figures. I added 3 crushed Campden tablets and let it sit for a day.

I then hydrated some Lalvin EC-1118 as the packet instructed, which was different than my usual method (in fact, this is my first time using Lalvin yeasts). Ordinarily, when I prepare a starter I follow the instructions from Jon Iverson's winemaking book, which calls for a larger amount of water, followed by some diluted must. In any case, the yeast woke up and started foaming so I added it to the primary.

It is now 24 hours later and there is absolutely zero activity in the airlock. There are no visible signs of life in the must, either. Could the fact that this is burnt honey be hindering fermentation, sort of like the way smoked meat prevents microbial activity?

I recall the only other mead I made (a hibiscus mead) was a sluggish one too. That began with some Red Star Pasteur Champagne that seemed to slow to a stop so I threw in some extra Premier Cuve that I had on hand. It picked up for a day or two, then disappeared. Half a year later it tastes great and definitely has a decent amount of alcohol, though I haven't measured the gravity yet.

Medsen Fey
01-09-2013, 07:08 AM
Can you please provide more details?
What other ingredients went into the must?
What is the must temperature?
What is the expiration date on the yeast?
Did you aerate the must well?
Exactly how did you rehydrate the yeast?

A bochet will normally ferment without problems. I suspect you just have a long lag phase and that it will start. I find that adding Campden tablets to a must sometimes causes this even after 24 hours which is one reason I don't use them routinely at the beginning (the other being that they are not needed with honey musts, especially those that have been boiled).

I'd aerate the must again and check the gravity.

What nutrients do plan to add?

duffrecords
01-09-2013, 04:04 PM
No other ingredients--just boiled honey, water, and the sulfites. I suppose the Campden tablets weren't necessary because the honey was boiled but the spring water was not. I'm just overly cautious because last year I had a wine must that surprised me with spontaneous fermentation so I learned to always sulfite my musts and let it bind with the sugars for 24 hours.

The temperature probably fluctuates between 60-70 F depending on the time of day (the house has poor insulation).

I don't know the expiration date but I just purchased it at my LHBS and I would hope they rotate their stock. I'll check the trash but that may have already gone out, as yesterday was trash day.

I didn't really aerate the must other than pouring it into the primary and stirring the water in. How would you recommend doing that?

I rehydrated the yeast by putting it in 50 ml of water at about 105 F (with that container sitting in a warm water bath to retain the heat). I had planned to pitch it after 15 minutes as the directions indicated but then I ended up talking to someone and it didn't go in until an hour later. The yeast in the starter was creating foam on the surface so it appeared to be active but when I pitched it, it floated on the surface and looked flocculated like those little grains when it comes out of the packet dry. That was weird because it was thoroughly dissolved when it was in the starter solution. The next day everything had sunk to the bottom.

I think I'll try adding nutrients. I usually add some Fermax and Yeastex, which tends to get things going, but I guess I forgot because it was late at night.

Chevette Girl
01-09-2013, 05:52 PM
I'm not sure from your post if you're fermenting in a bucket or a carboy, if it's a bucket, sanitize a whisk or large spoon and go to town till your wrists demand that you stop, you need to incorporate some oxygen into your must (and the agitation and aeration should also help get rid of any residual sulphites that may still be suppressing things).

If it's in a carboy, the easiest way is to siphon some out into a sanitized blender and whiz the crap out of it, pour it back in, stir, repeat a few times.

Most of us aerate at least once a day for the first 1/3 of fermentation.

It's also possible to get a dud pack of yeast, I've had one EC-1118 that was once (of several hundred batches, it's not common but it IS possible).

If after 48 hours there's still no signs of life, grab another packet, rehydrate according to the packet, then add an equal amount of must to the rehydration water after the elapsed time, by ten or fifteen minutes after that you should be able to see visible signs of fermentation and you can either keep repeating that and doubling the volume to get a nice big starter going, or pitch it in now that you at least know the yeast is alive.

Medsen Fey
01-09-2013, 08:22 PM
You probably lost a lot of yeast by leaving them unfed for an hour. That reduced your pitch count and between that and the sulfites you're seeing a long lag phase. It is possible to get a packet of yeast that are old or were otherwise damaged by poor storage, but that is less likely.

Aerate it well and check the gravity in a day or two.

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duffrecords
01-10-2013, 04:18 PM
Last night, I added some Fermax and Yeastex (1 tsp per gallon, as the package says) and then whipped the must into a froth with a big industrial whisk. This morning I saw a bubble pass through the airlock but gave up waiting for another. It's very slow. If I don't see more activity when I come home tonight I may pitch another starter of EC-1118.

duffrecords
01-11-2013, 05:36 PM
I came home last night and there was no activity. I aerated the must again, then created another starter (and, yes, the sell-by date is 2015). After hydrating it for 15 minutes at about 105 F, it was quite active, so I added a few spoonfuls of must to the starter. At first, it fell still but I submerged it in a bowl of 100 water and a couple of minutes later, the yeast started bubbling and rising to the surface again. I added some more spring water and must to add volume and let it keep roiling on its own for about 10 minutes.

I gently poured it into the must, which by then had a thick, foamy head from being aerated. I sealed the lid and several minutes later, the airlock began to emit bubbles very slowly.

This morning I checked on it and the airlock is still. ??? Maybe I need to put a heating pad around it or position the primary next to the wall heater.

Chevette Girl
01-11-2013, 08:00 PM
Give it another 24 hours to get started, and if you can put it closer to the heater that might not be a bad plan. And even if you're not aerating it, keep swirling it around to keep the yeasties in suspension.

duffrecords
01-12-2013, 10:23 PM
I moved it next to the wall heater, where the must is now a nice, cozy 81 F. It started bubbling (albeit very slowly) within minutes. I've aerated it with a whisk twice today and immediately afterward, the airlock bubbles steadily for a few minutes but then slows down to a crawl. The hydrometer says it's about 1% alcohol so far. Feels like this is going to be one difficult batch.

Medsen Fey
01-12-2013, 11:28 PM
When you checked the pH was that with a calibrated meter, or strips?

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duffrecords
01-13-2013, 02:56 AM
It was with both, although it's hard to get exact numbers from those pH strips. The color looks totally different depending on the light. I recalibrated my digital pH meter just now (it was only off by 0.03) and tested the must again. Now it's reading 3.33, which does seem a bit on the low side. Think I should add some calcium carbonate?

fatbloke
01-13-2013, 06:03 AM
It was with both, although it's hard to get exact numbers from those pH strips. The color looks totally different depending on the light. I recalibrated my digital pH meter just now (it was only off by 0.03) and tested the must again. Now it's reading 3.33, which does seem a bit on the low side. Think I should add some calcium carbonate?
No, I'd leave it "as is" for the moment, just keep aerating once a day minimum (I only tend to aerate once a day, some like to aerate twice or more).

It's dropped a few points so it's more likely just "lag phase" at the moment - the longest I've had with EC-1118 lagging, was over 3 weeks, but that's because I pitched dry into a must that I'd sulphited to kill off some wild yeast contaminants that had formed. Once it started it was fine.

New mead makers often are a little impatient. After all, with all that sugar content it should go mad right ? Wrong. A perfect balance of sugars, acidity, nutrient and correct temperature will often ferment very quickly, yet it only needs one of the elements to be out and it can take a while to start "properly"...... (that's presuming I've read your other posts correctly and haven't overlooked something).......

Medsen Fey
01-13-2013, 03:53 PM
The pH is fine at 3.3.
What is the gravity now?

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duffrecords
01-14-2013, 01:37 AM
Gravity is unchanged.

Medsen Fey
01-14-2013, 08:07 AM
This is a tough one, but I still think you are looking at a prolonged lag due to yeast handling. I think it will eventually pick up. I reread your posts and I see that you kept the yeast in a warm water bath which may have impaired them, and if you pitch 100 F yeast into 60-70 F must, the temperature shear will destroy a large percentage of the yeast.

Let me suggest you try the following:
A) Take 2 packets of the yeast (EC-1118) and add to 100 cc of water at 100 F. If you have Go-Ferm to add to the rehydration it does help.

B) Don't keep it in a water bath. Just have it on the counter. It is OK for it to cool down after the yeast have been stirred in.

C) After 15-20 minutes add 100cc of your must and let it sit until it starts bubbling actively. This could take anywhere from a few minutes to 2-3 hours.

D) When it is bubbling, add another 200 cc of your must. Again, wait for bubbling to be visible then stir it up and pitch into your must.

With the temperature shear less than 15 and acclimated yeast, it should go. If not, consider ordering a couple of packets of Uvaferm 43 yeast (the hardiest strain I know) and try pitching it.


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duffrecords
01-16-2013, 01:33 AM
I made a starter last night over the course of three hours, starting at 100 and letting it cool to room temperature on its own. I only had one packet of EC-1118 left and seeing as there seems to be something about the must that shocks the yeast, I added that in small increments--10 cc at a time, then 20 cc at a time, until I reached 200 cc. I also added a pinch of Fermax at the beginning to give them some fuel. The yeast was active the entire time (although with each addition of must it temporarily fell still). By the time I reached 200 cc it was still moving. At that point it was a 4:1 ratio of must to water, so that can't be radically different from what's in the primary. I aerated the primary and poured the starter in. The airlock kept bubbling and I went to sleep but this morning it had stopped. There were little, sparse clusters of bubbles on the surface, which I hadn't seen before, but tonight they had disappeared. I might try the Uvaferm 43, although I'll have to wait for it by mail because my LHBS doesn't stock it. They recommended Red Star Champagne, which I do have on hand. I've seen varying results with that strain. I made a mead last year that went very slowly and on the other hand I made a banana wine in the kitchenette at work that fermented to dryness in only 6 days. I don't want to wait too long for the Uvaferm in case bacteria sets in, although I did sulfite it on day one.

Anyway, here are some videos of the starter I took over the course of the night:

http://youtu.be/5HE2tMsk3pM
http://youtu.be/d11IGhUePCo
http://youtu.be/0BTyXoC9uIk
http://youtu.be/fzrDgkhlGzs

duffrecords
01-22-2013, 03:48 PM
I expedited a Uvaferm 43 kit and prepared it according to the directions (hydrate in a sugar water solution for 4-5 hours, then suspend the bag in the primary). While in the starter, the alginate beads were bubbling like mad. After I put it in the primary, nothing happened. I checked the gravity a few days later and there was no change. No bubbles were coming out of the bag either.

I read several bochet threads that warned about caramelizing all the sugars, so I entertained the possibility that there was a negligible amount of fermentable sugars left. After all, the honey had been boiling on the stove for two and a half hours. So I went to the store and bought enough honey for a fresh 5 gallon batch (15 lbs.). I dissolved the honey in a half gallon of water, mixed it into the must, and then topped the primary up with enough spring water to total 5.5 gallons (the extra half gallon to compensate for lost volume at the first racking). I also dissolved 2 tsp of Fermax and 2.5 tsp of Yeastex. So the total recipe now is about 11 lbs. burnt honey, 18 lbs. regular honey, and water to make 5.5 gallons. Well, that made the gravity super high--about 1.176--but at least I know much of that represents sugar that is not caramelized. The pH was slightly higher but I forgot to write it down. I prepared a starter of EC-1118 according to the packet's directions, then added a half cup of must. The yeast continued to churn (albeit more slowly). After a while, I added another half cup of must and waited. There was still motion in the starter at this point and it had created an inch-thick cap. I pitched it into the primary and at first there was gas slowly coming out of the airlock, but by the next morning it had fallen still. The next day, still no activity.

Last night, I prepared more Uvaferm 43 and after 5 hours, added about a quarter cup of must to the starter. It still continued to bubble healthily. In the meantime, I worked the must into a thick foam using a sanitized egg beater. I then lowered the bag into the primary, discarding the starter liquid, per the instructions. After the foam had subsided, I observed the bag, which was suspended only a few inches into the must. I could see bubbles rising to the surface as they did in the starter. I sealed the primary and saw gas being forced out of the airlock slowly but more vigorously than in my previous attempts. I strapped a heating pad to the primary and set it to low because the house has been getting cold at night. This morning, I checked the airlock and it was still. It wasn't even as though there was a bubble partially on its way out--the pressure on both sides appeared to be in equilibrium. I opened it up and swished the bag back and forth to disperse any by-products that may have accumulated around the beads. After closing the lid, I saw some outward pressure in the airlock but not enough to release a bubble. 15 minutes later, it was in equilibrium again.

This sucks. I've got a lot of money sunk into honey at this point and I'm tempted to throw some turbo yeast in there to get the job done, although I've heard it leaves disagreeable flavors. On the chance that there is insufficient oxygen in the must, I ordered an oxygenation kit with a diffusion stone which should be here by the end of the week. I can pick up a small oxygen tank at the hardware store. I still have some more Uvaferm 43 but if oxygenating the must doesn't help, I'm out of ideas.

Medsen Fey
01-22-2013, 09:29 PM
Let me save you some effort- if Uvaferm 43 won't ferment it, the turbo yeast aren't going to get it done. I'd consider splitting it into 2 batches and diluting it down by half. Then let the Uvaferm take it as far down as it will go, and after that you can step feed it to bring the ABV up if you like.

As a last option you can start a new batch (about a gallon in a 5-gal fermenter) and when it is going strong, I'd add the old must a little at a time keeping it fermenting until I got it full.

Medsen Fey
01-22-2013, 09:32 PM
Can you check the free SO2?

I'm just trying to consider all the possibilities.

duffrecords
01-22-2013, 09:55 PM
I should still have some Accuvin SO2 test kits left in my supply box. My email indicates that I ordered a pack of 10 back in 2011 so I couldn't possibly have used them all by now. I'll run a SO2 test tonight as well as take a new pH measurement. Hopefully they have not expired.

duffrecords
02-01-2013, 03:28 AM
Well, it turns out those kits expired in 2011. I tried them anyway, though. Unfortunately, the bochet is so dark that you can't see any difference. I did more tests on a 10% solution but the high/low SO2 readings weren't consistent with each other. I don't know how accurate these things are, over a year past the expiration date.

I bought an oxygenation kit, thinking I could dispel some SO2. By the time the kit arrived, I opened the primary to find a thin layer of bubbles on the surface (the Uvaferm's been in there all this time). Perhaps it was a really long lag phase. I pumped in the O2 for 30 seconds, prepared a fresh EC-1118 starter, and poured it in. The next morning, the airlock was bubbling and still is two days later. The progress is still slow, though. The gravity has only changed about 0.006 since adding the un-caramelized honey but at least that's progress.

Oxygenation:
http://youtu.be/6t6C4vkVrSo

duffrecords
02-15-2013, 06:30 PM
It's been a couple of weeks since my last post and the bochet is still fermenting. I've been stirring up the contents from the bottom almost every day to prevent stratification. It's currently about 7% ABV but the rate has slowed down considerably. During the first week it was yielding almost a full percentage point per day but now it takes several days for that to happen. One time the cup inside the airlock sank to the bottom until the next time I stirred it, at which point it started bubbling again. I've got that oxygenation kit--should I use that again? The kit's instructions warn against using it after the yeast have begun fermenting because it can impart off-flavors in wine, but this is mead and seems to play by its own set of rules.

In any case, it tastes good so far. It's complex and cloyingly sweet, obviously, because of the enormous amount of honey I started with.

Medsen Fey
02-15-2013, 06:47 PM
What's the current gravity?

duffrecords
02-15-2013, 06:50 PM
1.124

Original was about 1.178 (an approximation, since my hydrometer doesn't have graduations above 1.170).

Medsen Fey
02-15-2013, 09:11 PM
I didn't realize your starting gravity was off the scale. That's why this batch was slow in starting. Unless you dilute it, it will likely stall early leaving it very sweet.

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duffrecords
02-16-2013, 12:16 AM
Well, initially it was 1.112 but it wouldn't get started for the longest time, not even with Uvaferm 43. I thought maybe I had caramelized all the sugars into something the yeast couldn't use so I tried adding additional (non-boiled) honey, which is what brought the gravity up so high. But that didn't work either. It wasn't until I aerated it with a diffusion stone that it started to go.

By how much would you recommend I dilute it? It's currently about 5.75 gallons. I should point out that I have absolutely no problem with it having a high final gravity, as long as the ABV is appropriately high, like a port. But if it's going to run out of steam at only 7 or 8% then I'd definitely want to split it into two batches and dilute it.

WVMJack
02-16-2013, 12:54 AM
I just made a Bochet with all carmalized honey and it had no problems getting started and finishing. Any chance you might have added sorbate instead of sulfite? WVMJ

Medsen Fey
02-16-2013, 07:07 AM
Well you can try giving it more oxygen, and adding some yeast hulls and a bit more nutrient and see where it goes. If it stops early, you can dilute it and try to get it to finish, or you can consider fortifying it like a port.

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duffrecords
02-18-2013, 05:18 PM
@WVMJack: definitely not sorbate. I've only used a stabilizer once (sodium benzoate) and only because I had a gallon jug of banana wine fermenting in my office at work and everybody was clamoring to get it bottled ASAP. Ordinarily, I prefer to let time and gravity finish the job.

I'll try aerating again and adding some nutrients. The bochet seems to be hovering around 1.120 right now (just under 8%).

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WVMJack
02-18-2013, 07:34 PM
You must have a COOL office if you can have a fermentor in there!! Silly question, but what kind of pot did you burn your honey in? WVMJ


@WVMJack: definitely not sorbate. I've only used a stabilizer once (sodium benzoate) and only because I had a gallon jug of banana wine fermenting in my office at work and everybody was clamoring to get it bottled ASAP. Ordinarily, I prefer to let time and gravity finish the job.

I'll try aerating again and adding some nutrients. The bochet seems to be hovering around 1.120 right now (just under 8%).

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duffrecords
02-18-2013, 08:21 PM
It was aluminum. The local supermarket had these enormous stock pots for sale at a fraction of the cost of stainless steel so I picked one up--probably not the best choice, as the bottom became warped and discolored after boiling the honey for 2 hours.

Yes, my office is pretty cool. It's one of those internet start-ups where they try to foster a "fun" work environment. Making booze is fun for me and I'd say the end result had a positive effect on company morale, too.

WVMJack
02-18-2013, 09:55 PM
Can you taste the metal in your must yet? WVMJ

duffrecords
02-18-2013, 10:56 PM
I don't taste that. Why do you use the word "yet?" Will it rear its ugly head later?

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WVMJack
02-18-2013, 11:54 PM
A couple of years ago some folks who had been winemakers for a couple of years gave me a bottle of the best wine that they ever made. I popped it open and took a taste and it was all metallic taste over everything else, spit it out and dumped the rest. They had always used an aluminum funnel to pour their wine into the bottles since they started making wine and thought that part of the taste was normal. They thought I was crazy telling them not to use a metal funnel bottling their wine. I dont waste my time trading bottles with them anymore, I guess mine tasted funny to them without that metal taste.

Its possible, especially as you described how cheapo your pot is that it already warped on you, that you might have boilied an acidic fluid (mead) in a reactive aluminum pot and released enough aluminum to inhibit your yeast, I dont know if that is correct or not, but you seemed to have done everything else pretty good. Hit your mead with a huge dose of nutrient, rehydrate a fresh packet of EC1118 yeast, keep it warm, if that doesnt work your probably have something in there they yeast dont like.

WVMJ


I don't taste that. Why do you use the word "yet?" Will it rear its ugly head later?

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WVMJack
02-19-2013, 12:02 AM
. The hydrometer says it's about 1% alcohol so far. Feels like this is going to be one difficult batch.

Duff, what do you mean its 1%? What is the actual real hydrometer reading now? WVMJ

duffrecords
02-19-2013, 03:03 AM
That's an old post you're quoting. The original gravity was 1.112. Nothing happened for over a week so I feared the sugars were all caramelized. I added more un-boiled honey, bringing the gravity to 1.178. Still nothing happened. But then I aerated it with a diffusion stone and that woke it up. As of this afternoon, the gravity was 1.020 but airlock activity was minimal. I added 5 tsp of yeast hulls and aerated it again but the airlock was inactive after that. We'll see how it is tomorrow.

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WVMJack
02-19-2013, 06:21 AM
Got news for you, your mead was done fermenting a long time ago, its very hard to go from 1.178 to 1.00. Next time you need to post your actual gravity readings so folks can get a better idea what is going on. Put this puppy to rest for a couple of months in a nice cool place and let it clear. WVMJ


That's an old post you're quoting. The original gravity was 1.112. Nothing happened for over a week so I feared the sugars were all caramelized. I added more un-boiled honey, bringing the gravity to 1.178. Still nothing happened. But then I aerated it with a diffusion stone and that woke it up. As of this afternoon, the gravity was 1.020 but airlock activity was minimal. I added 5 tsp of yeast hulls and aerated it again but the airlock was inactive after that. We'll see how it is tomorrow.

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Medsen Fey
02-19-2013, 06:27 AM
As of this afternoon, the gravity was 1.020

Is that 1.020 or 1.120?

duffrecords
02-19-2013, 11:49 AM
@Medsen Fey: My mistake--I meant to say 1.120. It's interesting that it appears to be coming to a stop only 0.008 away from the original gravity of the boiled honey. Must be something wrong with that stuff, whether it was caramelization or a reaction with the aluminum.

@WVMJack: The gravity readings were mentioned in the first post and in several other places.

WVMJack
02-19-2013, 12:49 PM
Dude, I think you are screwed, get another pot and try again, everything the same but start at a lower gravity and use a nice pot. Its been a long time since this was started, it could be the pot, other people have scortched their honey a lot more until they had black smoke coming out of it and it still fermented so I dont think you cooked it to long to kill the sugar. Sorry but I thought you didnt post any gravity readings that showed the drop to 1.02 but which was really 1.12, your bad at typing and I cant remember everything :) Unless there is some parameter all the people on this thread have missed it might be time for the big dump, dont put it where any bees will drink it, the burnt honey is not good for them. WVMJ


@Medsen Fey: My mistake--I meant to say 1.120. It's interesting that it appears to be coming to a stop only 0.008 away from the original gravity of the boiled honey. Must be something wrong with that stuff, whether it was caramelization or a reaction with the aluminum.

@WVMJack: The gravity readings were mentioned in the first post and in several other places.

duffrecords
02-21-2013, 01:21 AM
That was a lot of money spent on honey, so I'm going to see if I can get some kind of return on investment. At 7.75% ABV that's like a strong beer but too sweet for anyone to want to drink an entire pint. I still had about a pound of honey left over so I mixed it with some hot water (to lower the viscosity) and then mixed that into the bochet. A thick foam appeared at the surface immediately. Once it settled down I checked the gravity but the change was negligible. I sealed the lid and the airlock has been bubbling steadily for about 24 hours now. Perhaps I can step feed it until the ABV gets sufficiently high. I'm going to leave it alone to do its thing until the activity slows and then I'll measure the gravity again. It seems like opening the lid and stirring it can sometimes slow or stop CO2 production.

WVMJack
02-21-2013, 09:29 AM
A couple things then, TAKE THE LID OFF, if taking the lid off stimulates it to activity it might not have enouh oxygen, take off the lid, stir the snot out of it and then stir it some more, I think you need to add some water to lower your gravity, if you had it at 1.178 it was way to high and you keep adding honey to it, more like you should aim to drop the gravity down to a more reasonable level like 1.095 so you yeast has a chance to finish fermenting. Good luck, WVMJ





That was a lot of money spent on honey, so I'm going to see if I can get some kind of return on investment. At 7.75% ABV that's like a strong beer but too sweet for anyone to want to drink an entire pint. I still had about a pound of honey left over so I mixed it with some hot water (to lower the viscosity) and then mixed that into the bochet. A thick foam appeared at the surface immediately. Once it settled down I checked the gravity but the change was negligible. I sealed the lid and the airlock has been bubbling steadily for about 24 hours now. Perhaps I can step feed it until the ABV gets sufficiently high. I'm going to leave it alone to do its thing until the activity slows and then I'll measure the gravity again. It seems like opening the lid and stirring it can sometimes slow or stop CO2 production.

Medsen Fey
02-21-2013, 09:56 AM
Duff,
There is a concept that you may not be familiar with - sugar is toxic to yeast and high sugar content inhibits yeast. This is one major reason why honey is stable. This concept can be expressed in the form of Delle units (DU). The formula for DU is:

DU = %sugar (w/v) + (4.5 * ABV)

In your mead, with gravity of 1.120 you have sugar of more than 31% (if you take out the impact of alcohol it would be higher). With an ABV of about 8%, this formula means you have in excess of 67 DU. This is enough to inhibit yeast in a harsh environment (low pH, sulfites, CO2 pressure, etc.). Above about 90 you won't have fermentation at all.

So when you have a struggling fermentation, adding more and more honey usually does not get you the desired result.

This batch may very well have some unidentified yeast inhibitor, and often the best way to handle that is to dilute it, and/or gradually add it into another healthy fermentation that will allow the yeast to get the job done.

duffrecords
03-03-2013, 01:03 AM
Well, it's gone from 1.178 to 1.110 (so 9% ABV) and the airlock is bubbling steadily. Does that Delle unit formula use the Balling or Brix scale or does that matter? I read that they "differ in their conversion from weight percentage to specific gravity in the fifth and sixth decimal places of the specific gravity scale." If so, the Delle units in my last post (according to my hydrometer, which uses Balling) would be 64.75 and today's measurement would be 67.

My girlfriend doesn't taste any aluminum in the bochet and her palette is highly acute, so I think we're safe from that.

mezmiro
03-03-2013, 08:25 PM
I'm going to be starting a bochet in the next few months, and this thread is a fascinating read. Lots of information packed in here. :)

I hope your batch turns out well! Glad to hear it's starting to ferment a bit better for you.

Side question, is there such a thing as burning a bochet too much? I've seen different recipes where they barely caremalize the sugar at all, and others where you boil it until black smoke appears. Does this damage the honey at all?

Marshmallow Blue
03-03-2013, 09:37 PM
I think once you heat the honey. It is technically damaging it since your cooking some serious aromas, is it a bad thing for a bochet? Maybe not. My fear of the dark bochet has the color of spent motor oil but it tastes really nice, smooth, and complex. It's all in what you're going for.

duffrecords
04-06-2013, 07:14 PM
Well, the fermentation seems to have come to a stop at 1.106, which makes it about 9.5% ABV. I'm going to dilute it and restart fermentation but I'm not sure how to calculate the ABV after that. Let's suppose I were to split it into two batches and add a gallon of water to each, lowering the specific gravity. How would I determine the ABV after it's been diluted?

Alternatively, I could transfer the entire 5 gallon batch to my 6.5 gallon primary and dilute it only marginally. Do you think that would be sufficient to bring the ABV above 12% or would I be better off splitting it in two where I'd have space to dilute it more aggressively?

Medsen Fey
04-07-2013, 02:38 PM
Well, the fermentation seems to have come to a stop at 1.106, which makes it about 9.5% ABV. I'm going to dilute it and restart fermentation but I'm not sure how to calculate the ABV after that. Let's suppose I were to split it into two batches and add a gallon of water to each, lowering the specific gravity. How would I determine the ABV after it's been diluted?

It looks like you're at 70+ Delle units, so your yeast have done pretty well.

You can calculate the dilution using the following formula that works for blending:
(ABV*V) + (ABV*V) = (ABV*V)
ABV is the ABV of the first batch.
ABV is the ABV of the second batch. (which is zero if you are adding water)
V is the total volume (equal to V+V)

So if you have a 5-gallon batch that you split in two, you have a V of 2.5, and the the ABV is 9.5%. If you add a gallon of water, the V is 1 and the ABV is zero so that term goes away. The V will be 3.5. So your ABV will be:

(9.5%*2.5) + (0*1) = (ABV*3.5) so,
(9.5%*2.5)/3.5 = ABV
6.8% = ABV

If you use different dilution volumes you can plug them in and know where you'll be. This same methodology works for calculating the ABV effect of back sweetening, or topping up.

duffrecords
04-07-2013, 05:33 PM
So if I wanted to calculate the resulting percent sugar after diluting, would that also work like this?

(sugar*V) + (sugar*V) = (sugar*V)

Medsen Fey
04-07-2013, 05:53 PM
Yep, and if you get your volumes measured right, you'll be able to confirm with your hydrometer.

WVMJack
04-07-2013, 07:31 PM
There has got to be an app for that somewhere! WVMJ

duffrecords
04-08-2013, 02:52 AM
I made a spreadsheet that calculates the change in %sugar, ABV, and Delle units, and then their corresponding values if fermentation could (theoretically) complete to dryness. At first, that theoretical number goes above the current Delle units (67.82) but then after adding 0.9 gallons of water, it opens the door for further fermentation. I'd like this thing to be at least 12% ABV so it looks like I should add 2.5 gallons to allow that. Above that, it seems to roll off logarithmically, so I guess I can't expect much more than that.
http://duffrecords.com/images/theoretical-abv.png

duffrecords
05-23-2013, 12:41 PM
I finally got some free time to split the batch into two 2.5 gallon batches, diluted by a gallon of water each. The hydrometer now reads 1.080 SG and 19.5% sugar (Balling). By the blending formula mentioned by Medsen Fey, the ABV should now be 6.8%, which brings the Delle units somewhere around 50.1. I prepared two starters of Red Star Premier Cuvee (since it yielded 18% in the hibiscus mead I just bottled). After 15 minutes of hydration, I added about 1.5 tablespoons of the partially-fermented bochet to each starter and agitated them. After about an hour, they both were producing a thick, foamy cap so I poured them into the primaries. The airlocks bubbled for a few minutes but this morning (about 12 hours later) they were still. The yeast might be in the lag phase. I unsealed the lids, hoping they will benefit from less pressure. Man, this has been my most difficult batch yet.

duffrecords
06-01-2013, 01:05 AM
Fermentation seemed slow so on 5/26 I made two new Premier Cuve starters and built them up incrementally over the course of a day, as Jack Keller's web site advises. At first, it created a big, foamy cap but the more must I added, the less visible the activity was. I pitched it on 5/27 and waited. SG on 5/23 was 1.080; now it is 1.070, so the yeast is doing something, even if the liquid is still. This was the same experience I had the last time I used Premier Cuve on a mead. Hopefully, it will stealthily make its way up to 18% like that batch did.

Medsen Fey
06-01-2013, 12:14 PM
When restarting a really challenging batch, it is common to see little activity and just a slow drop in gravity. I would suggest that you aerate it well, give it some yeast hulls, and try to keep the temp up to at least 70F, then be very patient.

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duffrecords
06-07-2013, 01:55 AM
I mixed 3.5 tsp of Yeastex into each primary and aerated them with an O2 tank and diffusion stone for about 30 seconds each. The foam gradually dissipated but by the next morning, a fine film of bubbles had appeared on the surface. Tonight I measured the SG delta of each buckets and added that to the initial 6.8% ABV (after dilution). They've reached 10% and 10.3%, respectively. Getting closer!