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View Full Version : Stuck Cyser - Time to build a starter?



icedmetal
02-15-2010, 11:16 PM
Hello! I've been lurking for months, about time I contribute a little something meaningful to this excellent resource. We (my wife and I) have been making hard cider for a few years now, and started building meads in 2008.

Sometime shortly after pitching yeast on these batches, I found this site, and began studying. I've since picked up a few books (inc. the Compleat Meadmaker) and read them quite thoroughly. I say this by way of explanation; the procedure and recipe below is something I was taught by a friend, and does not reflect my current understanding of mead at all. I plan on starting a different thread in Recipe discussions where we can go into detail about all the things wrong with the process we used.

Background: We started the batches (there are two, same recipe and same behavior) on 10/05/09, 24 hours after hand-pressing the cider. I don't know what kind of apples they were; will try and find out.

Ingredients list:
18lbs clover honey
1t Irish Moss (yeah, I know...)
1T Gypsum
2T Yeast Nutrient (Brewcraft brand)
4632 Wyeast - Dry Mead Yeast
Fresh Cider to the 5 gallon mark

Procedure:
At pressing time, we added crushed campden tablets to the tune of 1 per gallon. We boiled the honey and nutrients and pitched on the following day, just over 24 hours later. All sanitation accomplished using common household bleach.
0. Break open the Wyeast smack pack and let it sit at room temp (70F) for a couple hours.
1. Combine all ingredients except cider and boil for 5 minutes, stirring constantly. Temperature reading after 5 minutes boiling was around 220 degrees fahrenheit.
2. Remove from heat and cool to pitching temp. Pitching temp was 67.7 degrees fahrenheit.
3. The OG was 1.145, and from that I came up with a 19.5% potential alcohol. I haven't double-checked that figure on the mead calculator yet but plan to do so.
4. We pitched the yeast, stirred like crazy, and let it sit for a week.
5. On 10/12/09, we racked it from the primary fermenter (8 gallon brewcraft bucket with a tight-sealing lid and airlock) to the secondary, a 5-gallon carboy. Sorry, we didnít take a hydrometer reading.
6. We ignored it! No idea how long it went for before the fermentation ceased; if I had to put a line in the sand Iíd guess it went for a month or more before the airlock ceased bubbling.

At some point we noticed that was no further airlock activity, and so took a gravity reading. 1.061 SG, and quite tasty, if a bit too sweet. A little math, and we concluded that there was far too much residual sugar for the yeast we used to have finished to completion.

Fast forward to the past week. Our PH meter came in the mail, and we got a temperature-corrected reading of 3.5. This seems on the low end, but not terribly low. We also re-checked the gravity, and confirmed found it to be the same as before, 1.061 and apparently holding steady.

The plan:
1. Adjust the PH to 3.8 by adding Potassium (bi)carbonate 1/2tsp at a time. Since the samples get thrown out after each addition and test, this could get expensive in terms of wasted product.
2. Rehydrate Lalvin EC-1118 using Go Ferm (also just came in the mail!) and build a starter out of the rehydrated yeast.
3. Pitch the starter.
Ö.
4. Wait for action and adventure!

Questions:
0. Are we looking in the right direction at all here?

1. Honestly Iím not sure about the best way to build this starter. Iíve read about some folks adding some of the must to the starter to help acclimate the yeast; is this something we should do?

2. I was leaning toward not using must in the starter since while in the starter, the yeast should be in its growth phase, and all youíd end up doing is stressing the yeast. Is that correct?

3. Post-starter pitch, what other work have we earned with these batches? It seems that in addition to the typical aging required of any mead, these will also require a couple weeks' cold crash to knock the potassium (bi)carbonate out of suspension. Anything else?

4. Which should we use, potassium carbonate or potassium bicarbonate? We've managed to find both, and now are having trouble finding comparison data that would point us toward one over the other.


Thanks for taking the time to read all this... hopefully we'll all learn something new together!

Displaced Hick
02-15-2010, 11:43 PM
I have read that the Wyeast mead yeasts can be a little finicky. Not sure what to tell you about that but if you want to pitch another yeast to try and restart fermentation go to Hightest's Honey Haven (http://home.comcast.net/~mzapx1/). I have found his information VERY useful.

By one of the ABV calculators I use, it looks like this is just a hair under 11% right now.

wayneb
02-16-2010, 12:01 AM
Regarding the restart protocol, I also like Hightest's approach, which is very similar to one that our own Oskaar came up with a few years ago - if you use the search tool with restart as the key word and Oskaar as the author, you should find it.

It doesn't seem that pH is your problem; 3.5 is right in the "sweet spot" for most yeast strains. They don't begin to be stressed until the pH drops below 3.4 or so. Although that's only 0.1 change, it is a significant increase in net acidity (pH is a logarithmic scale), so I don't believe you are in a bad spot with your current pH.

I suspect that the yeast strain you chose just doesn't like to start in ultra high gravity musts. Any time the initial gravity is over about 1.135, you're asking a lot of any yeast to go to dryness. Often, even yeasts with high ethanol tolerance can be stunted by the osmotic shock of an ultra high gravity must. Much care is needed in such fermentations, including adequate aeration early on, staggered nutrient additions (carefully monitoring the net amount of YAN to ensure that you add enough, but not too much), and the like. A must with an initial gravity of 1.145 isn't a "set it and forget it" kind of thing, unless you don't mind if it finishes on the sweet side.

Medsen Fey
02-16-2010, 11:05 AM
Questions:
0. Are we looking in the right direction at all here?

1. Honestly I’m not sure about the best way to build this starter. I’ve read about some folks adding some of the must to the starter to help acclimate the yeast; is this something we should do?

2. I was leaning toward not using must in the starter since while in the starter, the yeast should be in its growth phase, and all you’d end up doing is stressing the yeast. Is that correct?

3. Post-starter pitch, what other work have we earned with these batches? It seems that in addition to the typical aging required of any mead, these will also require a couple weeks' cold crash to knock the potassium (bi)carbonate out of suspension. Anything else?

4. Which should we use, potassium carbonate or potassium bicarbonate? We've managed to find both, and now are having trouble finding comparison data that would point us toward one over the other.


Building the starter is only half the battle - getting them ready for your must is another important piece. While it is possible to pitch ADY without making a starter, and without acclimating the yeast, in my experience, acclimating improves the chances of success. If you throw yeast into an acid medium with an alcohol content of 11.5% ABV, that is a HUGE shock to their system. If you take a equal parts must and starter mixed together the yeast are only being hit with 5.75% ABV at the start - still a big number, but a lot less stressful. Once they've adjusted to that environment, adding another portion brings you to about 8.5% ABV, and when the yeast can function there, the odds are better that they'll be able to function in the must. In studies of restarts the the two biggest factors influencing the success seem to be the alcohol level and the SO2 level - higher levels of these two substances really hamper the yeast.

Another big factor is sugar. High sugar levels inhibit yeast function and you still have greater than a 15.8% sugar solution. If your must was nearly dry at 11.5% ABV, getting it finished would not be so challenging. At this level of sugar, with that level of alcohol, the yeast are going to have a very tough time. Even if they do ferment further, expect it to be a slow process without too much visible activity, just a slow drop in gravity over several weeks.

One thing that may be helpful is to treat your must with yeast hulls to bind any yeast inhibitors - 1 gram per gallon would be plenty. I'd also aerate it very well.

At the current level, the pH sounds just fine and I don't think you need any adjustment. You can use either the carbonate or bicarbonate they will work equally well. Neither of these will precipitate out when the mead is cold. The term "cold crash" is used for stopping fermentation of the yeast by refrigeration. "Cold stabilization" is a term used in winemaking for storing a wine in cold conditions to precipitate potassium bitartrate - but most mead has little or no tartrate. There isn't a common term (that I know of) for chilling mead to help speed clearing - we could coin one. :)

I hope you are able to get your batch going again.

Endeavor to persevere!
Medsen

wayneb
02-16-2010, 11:41 AM
Hightest's, as well as Oskaar's protocol for restarting fermentations are both derived from Lallemand's recommendations to restart stuck wine ferments, and both approaches recommend several doses of existing must to the starter, to properly acclimate the yeast. Kudos to Medsen for explicitly pointing out the need for that acclimation, since without it your odds of success are dramatically reduced, especially in a must that already has a significant amount of ethanol in it.

icedmetal
02-16-2010, 11:10 PM
Thank you all for the replies, tons of great information here. We'll put a starter together in the next week or so and tackle the first batch. And of course, I'll keep this thread up to date with any developments. Now, off to the recipe forum to tear apart this debacle of a mead...

icedmetal
03-16-2010, 03:04 AM
Ok, so it took us way longer than a week to finally get around to building the starter. We used this procedure (http://home.comcast.net/~mzapx1/FAQ/StuckFerm.pdf) to build our starter, and went with EC1118. About 3 hours after pitching the starter, we've seen some small amount of activity in the airlock. Yay!

We'll take a gravity reading tomorrow and see where it's at. Our expectation is that it'll have dropped significantly, mostly due to the starter's gravity being much lower than the rest of the must.

Right now the starter seems to have stratified in the top half of the carboy. The bottom half isn't nearly as clear as it was before, but the top half is noticably heavier in yeasties. Is this OK, or should we give it a stir?

Medsen Fey
03-16-2010, 08:52 AM
I'd stir it a bit. A little aeration can only help.

icedmetal
03-16-2010, 11:56 AM
A little, or a lot? I've got the drill-mounted stirrer, or the handle end of my longhandled plastic spoon...

This morning the bubbling has sped up to around a bubble every 10-15 seconds. Woohoo!

Medsen Fey
03-16-2010, 12:20 PM
A little. I'd try to get it mixed in well while aerating it once and then I'd wait and see.

icedmetal
03-17-2010, 03:30 PM
Stirred last night with the back of the spoon. SG was 1.052. We're now bubbling ~1.5 seconds apart and visually there's a lot of CO2 rising through the must.

We took a PH test, which seemed to be at 3.9, however it looked as if the probe on our meter may have partially dried out. We'll re-calibrate it tonight and see what happens...

icedmetal
03-30-2010, 05:11 PM
Calibrated the PH meter and found it to be in good functional shape. So yes, 3.9. It's still bubbling away, and we're getting antsy to restart the other batch. Will take more readings and a taste test soon...

-SIRES

icedmetal
02-07-2011, 03:26 AM
Long overdue update. Although it seemed there was some fermentation action, overall there was only a 13 point drop, from 1.054 to 1.042. That can probably be accounted for by the change in gravity from adding the EC1118 starter. The other batch we attempted to restart with Uvaferm 43, the results were quite similar.

So, we made this years' cysers go dry intentionally, and have now blended them with these stuck batches. That ought to knock about 25 points off the final gravity. Yay!

icedmetal
11-19-2011, 01:07 PM
Successfully blended these sweet cysers with the dry cysers I made the following year. Over the past two weekends, bottled all 20 gallons ;D Cyser, cyser, everywhere!

YogiBearMead726
11-19-2011, 01:23 PM
Successfully blended these sweet cysers with the dry cysers I made the following year. Over the past two weekends, bottled all 20 gallons ;D Cyser, cyser, everywhere!

Awesome! It sounds like you managed to overcome the stuck batch issue with a wonderful solution. :) I've always wanted to try blending, but have yet to try it out.

TheAlchemist
11-19-2011, 01:49 PM
Cyser, cyser, everywhere!

And Plenty of drops to drink!
Good on ya, Mate.