Stuck Mead

[moovet]

I put down a wife pleaser mead 5 weeks ago according to BrewerPetes recipe including the nutrient additions and aeration -did have one boilover during the last aeration though.
As I had to use the brewfridge for a Dunkelweisen and Doppelbock, I took the mead out after two weeks for about 3 weeks total. The first two weeks were relatively warm but the last week the fermenter temp went down to about 15 degrees. The SG was then 1.054 after an OG of 1.140.

I put it back in the brewfridge at 21 degrees and after a week of that it is clearing slightly and has gone from 1.054 to 1.052 so I think I may have a stuck fermentation.

If I give a gentle stir of the sediment without aerating the mead, will that crank it back up at that temp or will I need to make up another 71B starter or use EC-1118?

Any advice as always appreciated to get this back on track.

Cheers,


M

 

[davewaldo]

If you're not in a rush for it to clear, swirling it around and mixing in the lees is a good idea. No more aeration as you correctly state.

Without putting those numbers into a calculator I'm guessing its around 10% now, which might be the alc tolerance of your yeast so it might be all you're going to get.

What does it taste like? I made a dessert mead once which was around 1.045, it was sweet but nice.

Cheers,

Dave.

 

[moovet]

If you're not in a rush for it to clear, swirling it around and mixing in the lees is a good idea. No more aeration as you correctly state.

Without putting those numbers into a calculator I'm guessing its around 10% now, which might be the alc tolerance of your yeast so it might be all you're going to get.

What does it taste like? I made a dessert mead once which was around 1.045, it was sweet but nice.

Cheers,

Dave.

Hi Dave,

Yes it is around 10% which is a bit below the tolerance range of this yeast - Should be up to 14%.

It tastes alright but definitely a bit sweet.

Cheers,


M

 

[unrealeous]

Hang on am I reading this right. The OG was 1.054 and now it is 1.052 after 5 weeks? Doesn't sound stuck - sounds like the yeast are dead.

 

[moovet]

OG was 1.140 and after 4 weeks was 1.054 and after 5 weeks 1.052

 

[pdilley]

Not to fear Moovet. Your Mead is doing well. 71B is up to 14%. One thing that can drastically slow or stop a ferment is pH. If it's below 3.5 it can have an effect on your yeast. Your water source and even honeys can be more acidic than others. You may want to test for pH if you have the kit. A tiny bit of calcium carbonate will bring it up for you close to 3.8 for you. You may also have a stratification in your still ferment and stirring up the must will help. Also this is why racking helps as it destrasifies, outgases a bit of the built up CO2 in solution and mixes up a bit of yeast. You can also add a tiny bit of nutrient during racking or stirring to help things along.

If you are in a rush then ec1118 will pull you down but lower than you want so you just need to add honey slowly after it is done to get the gravity dialed in right for your taste. A bit longer to age though due to higher alcohol levels.

Cheers,
Brewer Pete

 

[moovet]

Not to fear Moovet. Your Mead is doing well. 71B is up to 14%. One thing that can drastically slow or stop a ferment is pH. If it's below 3.5 it can have an effect on your yeast. Your water source and even honeys can be more acidic than others. You may want to test for pH if you have the kit. A tiny bit of calcium carbonate will bring it up for you close to 3.8 for you. You may also have a stratification in your still ferment and stirring up the must will help. Also this is why racking helps as it destrasifies, outgases a bit of the built up CO2 in solution and mixes up a bit of yeast. You can also add a tiny bit of nutrient during racking or stirring to help things along.

If you are in a rush then ec1118 will pull you down but lower than you want so you just need to add honey slowly after it is done to get the gravity dialed in right for your taste. A bit longer to age though due to higher alcohol levels.

Cheers,
Brewer Pete

Thanks Pete. Will give it a stir tonight with a bit of nutrient and measure the pH tomorrow at LHBS. Not in a hurry so like to avoid ec1118 if possible. It is supposed to be a wife pleaser after all.

Cheers,


M

 

[Airgead]

The 71B datasheet gives the temp range as 15-30c and specifically mentions avoiding cold shocking the yeast. My guess is the drop to 15c caused it to stop and floc out. A rack or a stir (without oxygenation) and some nutrient should kick it back to life.

If you leave it alone it will probably finish fermenting but will take ages. Ferments like that can take months to complete.

Cheers
Dave

 

[pdilley]

Thanks Pete. Will give it a stir tonight with a bit of nutrient and measure the pH tomorrow at LHBS. Not in a hurry so like to avoid ec1118 if possible. It is supposed to be a wife pleaser after all.

Cheers,


M

Sounds like a plan. Or if you want you can take care of racking it and then drawing off some liquid to test in the one go as you'll always have left over must and trub after a racking. So for others reading along with test strips don't dunk into the fermenter but instead draw odd a sample

Yeast acidifies the must as it metabolises and we deal with yeast over a longer haul than beer brewers so for the next batch start doing starting pH readings and dial in your starting pH if needed with calc

ium carbonate a 1/2 tsp at a time stirred in then retested etc.

I'd be looking for a pull of at least 100 points to be happy with the way the ferment is progressing. You are close but still under and with 71B I'd say something is suss whether it's a simple stratification (1st racking always good at this time) or pH went out of range.

Edit: Unlike beers, mead fermentation is like a relaxed game of chess, there is plenty of time to sit around and think out your next move to progress the game along so there's a lot less pressure

Cheers,
Brewer Pete

 

[moovet]

I'd be looking for a pull of at least 100 points to be happy with the way the ferment is progressing. You are close but still under and with 71B I'd say something is suss whether it's a simple stratification (1st racking always good at this time) or pH went out of range.

Cheers,
Brewer Pete

Hi Pete,

You are onto it. Got a sample tested today at LHBS and it was 3.38 so most likely the problem.

Do you have any recommendations for digital pH meters? I am colourblind and no doubt the pH strips will be a waste of time and money for me.


Cheers,

M

 

[Wolfy]

Do you have any recommendations for digital pH meters? I am colourblind and no doubt the pH strips will be a waste of time and money for me.

Ebay ones are servicable, and usually the same as you find at the local shops but 1/4 the price.
Just pick an ebay seller that offers a warranty and you'll be fine.

 

[moovet]

Ebay ones are servicable, and usually the same as you find at the local shops but 1/4 the price.
Just pick an ebay seller that offers a warranty and you'll be fine.

Cheers Wolfy. Always dubious of the ebay gadgets that come direct from Hong Kong or China.

Any idea on how the ebay refractometers perform?

Cheers,


M

 

[Wolfy]

Cheers Wolfy. Always dubious of the ebay gadgets that come direct from Hong Kong or China.

Any idea on how the ebay refractometers perform?

I've often found that the ebay-items look identical to the ones found in local shops for 3x the price, sure looks are not everything, but most stuff like that is 'made in china' anyway even if you buy it from a shop. Local support/warranty is always nice, but my pH meter broke so the Chineese ebay people are replacing it under their 1 year warranty, so the only difference to a shop is that I have to pay postage.

There is a big thread about ebay refractometers somewhere here, where you'll find that a fair few people use them without problem (I use mine almost exclusively now - and love it).

 

[pdilley]

Some pH meters will have replaceable probes for a bit more money than non-replaceable meters.

However after looking into the costs for new probes (most don't mention the price) its almost as much as a new meter anyway

So I don't know if I would spend more money for a probe replaceable meter or just toss and buy another one. I don't use digital meters yet for pH so I am not able to help give first hand experience yet. I plan on moving to them when the paper runs out.

EDIT: My eBay refractometer performs like a champ!

Cheers,
Brewer Pete

 

[moovet]

Well it has been about a week. I have ordered a pH meter and refractometer from the ebay guys BP recommends. In the meantime I have been taking a
sample to my LHBS for pH readings daily after adding 1/2 tsp Calcium Carbonate to the must.

After 5 additions it is currently at 3.65 from starting pH of 3.35 so I stirred in another 1/2 tsp Calcium Carbonate and 1/2 teaspoon of yeast nutrient today. In the time it has taken to get to this stage however there has still been no change in SG.

I will do another pH reading on Monday at the LHBS (is a 25min drive so can't be blowed going again today). I was hoping there may have been some
movement in the SG as the must was becoming less acidic. Just wondering whether I should be innoculating more yeast as the next step if it doesn't
restart. Would still like to avoif EC-1118 if possible.

The lady at the LHBS thinks I have killed the yeast with too high alcohol but I am sure it is only about 10% at the moment. Rechecked my hydrometer at 20 degrees C and no problem there.

Is there any harm in making up a starter with more Lalvin 71B? Or should I just wait till the pH is stabilised at 3.8 for a week and retest the SG then?


Cheers,


M

 

[pdilley]

You are on the correct track moovet. Once your pH is adjusted you can try and fire off some more 71B (doing a starter would be nice with the initial 10% alcohol to give them a fighting chance) to see if it will pull your sugars down for another 3-4% abv. You do not need to hit the full 3.8 as you have most of the fermentation taken care of so you are in a good range to try for the last bit of sugars with the same yeast. If no joy, then consider either volumetric dilution for sweetness adjustment or going with the EC1118 and do a volumetric honey addition to bring the final gravity back up.

You can also use your numer of additions to volume of must between pH tests to determine the effectiveness of the additions and find out what amount will adjust what level of points and mark it down for later brewing.

You can draw off a sample to taste as is as well as then do a volumetric dilution with water to see if you like it dilute or want to keep doing a full ferment with yeast(s).


Cheers,
Brewer Pete

 

[moovet]

Well it has been a week since I added a new 71B starter to the must and the specific gravity hasn't moved an inch using the hydrometer. I may have not let the starter adjust enough to the added must as it seemed to be doing well and when i added the remainder of the must it lost its foam and didn't develop it again that night. I pitched it anyway as I could see small bubbles forming at the bottom and going to the surface.

I used the remainder of the 25g 71B sachet I used originally which seemed to hydrate well and foamed with addition of some of the wort after 30min. This sachet was from my LHBS but I have some 71B from Wolfys bulk buy so will try a starter with that and if no movement in a week decide whether to EC-1118 and backsweeten or dilute the
current wort out.

Cheers,

M

 

[pdilley]

You've done all the right things so far. Other causes of stuck are lack of nutrients, high sulphite levels, temperature too low and you have all those checked off. Or quite simply fermentation might be done. If its done, you may need to cross-calibrate your hydrometer at the high amounts of sugar ranges - so do a test sample measured at 1.140 on your hydrometer against a Refractometer reading. Take notes of your process and ingredients (brand names) for knowledge in formulating the next few batches as each honey is made of more than a hundred ingredients in different levels that you can sometimes get a specific varietal grown in a specific area with an effect on fermentation.

I can also give you honey weights so you compare weight of honey diluted to set amount of water and compare hydrometer readings to see if your scale is off and you may have mixed higher than 1.140 starting gravity.

But all is not for naught. After a week, the options now include finding a 16% ABV yeast in case your starting sugars were higher and all you need is 2% more alcohol from consumed sugars. Or using an 18% ABV yeast if worried about the nutrient/osmotic/abv state of your must and want to give it a fair go in case of petering out and then back sweeten with more honey if you over shot the mark.

If worried about the must, then aclimate your starter to the must itself by starting with a 1/2 cup of vigorous starter and adding 1/2 a cup of the must to the starter with 1/4 tsp DAP Yeast Nutrient. Wait until the yeast recovers and ferments again and then add another hit of must and nutrients. Then wait until yeast recovers yet once more and add another hit. When the yeast has toughened up pitch the starter with good vigorous stir into your main mead ferment.

Cheers,
Brewer Pete


EDIT: For volumetric dilution, keep in mind small amounts are better. For example to get half the Final Gravity of residual sugars you need to dilute with the exact same amount as your starting volume. Giving a 50% dilution in flavours, aromas, sugars, etc. At a gravity of 1.050 to drop to say a gravity of 1.040 that is a 1/5th or 20% dilution. Less than the 50% but still may not be right to your taste buds. You can run this in reverse with starting with a set sample size, adding a set amount of water to dilute and taste testing as you keep adding a set sample size. You may find to your taste you like it with only a 0.005 gravity drop instead of a full 0.010 gravity drop etc.

 

[moovet]

If its done, you may need to cross-calibrate your hydrometer at the high amounts of sugar ranges - so do a test sample measured at 1.140 on your hydrometer against a Refractometer reading.

I have put 97g of honey with 160mls water at 19 degrees and got a hydrometer reading of 1.141. The refractometer reading was 31.4 which seems too low (should be 32.4 according to chart). Both the hydrometer and refractometer measure 0 with tap water (17 degrees C). Doesn't sound like the hydrometer is the problem. Maybe the refractometer is not that accurate but doesn't look like the must was a higher SG than measured.

I can also give you honey weights so you compare weight of honey diluted to set amount of water and compare hydrometer readings to see if your scale is off and you may have mixed higher than 1.140 starting gravity.

I would appreciate that thank you.

I think I will do the EC-1118 or DV10 as it may not be quite as high an alcohol tolerance (16-18). If it gets too dry I will try back sweetening. I don't want to dilute out the flavour as it is very nice, just a bit sweet.

Cheers,


Geoff

 

[moovet]

Also tried the refractometer on a sugar solution.

93g sucrose made up to 250mls was 39.3 Brix

93g sucrose and 250mls water was 26 Brix

I used the Got Mead calculator to calculate the amounts. If I used it right, 93g of sugar in a Target volume of 250mls should have been 32.2 Brix so don't know where I have screwed up there!!!! My brain is fried so might have to work it out tomorrow (or repeat it!!)