Help needed - problem with a batch

[Jim H]

Hi all: I think I may have caught this early, so hopefully with a little advice, you'll steer me in the right direction.

I have a batch (here) that was scheduled to move to secondary today. When testing its gravity, I had found that it had not moved in 8 days, and in fact may have gone up a wee bit.
Important points: calculated OG: 1.121, today's reading: 1.068. Using K1V, 11 lbs honey for 3 gals, 42 days. I racked it to secondary today on schedule, adding 1/2 tsp DAP and 1/2 tsp Fermaid-K. Divided up into two carboys to allow room for must.

What should I watch for -- is this a stalled batch?

 

[Jim H]

After some more research, I found Hightest's FAQ on stuck fermentations. According to the calcs, I am right at the 50% fermentation mark. So, the his note on it was to stir vigorously for a few days -- get out the CO2 and get some oxygen to the yeast.
http://home.comcast.net/~mzapx1/FAQ/StuckFerm.pdf

And, that's what I started to do tonight.

Does his advice match your experiences?

 

[rmccask]

At the halfway point, I am not sure the DAP or Fermaid K will do any good. If you have some yeast hulls you could add some of that, if not, boil some (bread) yeast and add that. You could also cut some raisins in half and add those. If you do some searches for "yeast hulls" and "boiled yeast" here you can probably get more details by more experienced people.

 

[Jim H]

Yeah, kind of a bummer being a newbie and getting stuck. I did the thing that I thought would help... and what do you know? I might have hurt it, adding that Fermaid-K and DAP.

Anyway, I have plenty of bread yeast I can boil if I need to. For the next couple of days, I will try Hightest's method of stirring vigorously and get some air in there. I am right at the halfway point, so I think it might be safe enough to do. If, on Wednesday, gravity still isn't moving downwards, I will make a starter with my spare K1V packet.

 

[fatbloke]

The problem may indeed be nutrient related, but equally, it might be acidity/pH related too.

You'd need to test the pH because if its dropped below 3.0pH it can stick or slow down.......

If it did work out to be the problem, then potassium carbonate is your friend.....

 

[rmccask]

I doubt the nutrients you added will be a big problem but I doubt they will help either so I wouldn't dwell on that.

If you haven't, I would check the pH before you do anything else since if it is too low, that could be your problem and you can add something to raise it a little. If the pH is ok, then I would do the boiled yeast before repitching personally since the existing yeast, if they are alive, are already acclimated to the alcohol and creating a yeast starter will take more time.

 

[Jim H]

Ok, I just tested the pH. The color is definitely strongly acid, 3 or lower.

I do not have potassium carbonate. I will have to order some, there's no way I can go and get any in person this week.

How long can this must stay at this pH before permanent damage is done? Will it keep for 3-4 days, and be able to start up again after I get the chems?

 

[rmccask]

Degassing it may help to lower the pH a little while you are waiting to get some potassium carbonate or potassium bicarbonate. If the pH gets too low then I have heard it can kill the yeast but for most cases I have read about, the yeast will come back to life when you get the pH under control. I now add 1.3 g of potassium bicarbonate per gallon to most of my batches before I even pitch the yeast.

If it doesn't start back up within a few days of raising the pH, then you can think about creating a starter but hopefully you won't need to.

 

[Jim H]

Ok. I will also get an extra packet or two of K1V, just in case.

How about cream of tartar? I see on some other brew boards that cream of tartar is sometimes used to raise pH... which confuses me, because it's an acid.

 

[rmccask]

I don't recommend the cream of tartar. Here is link to a posting that talks about adding cream of tartar by wayneb, someone with more knowledge about this than me.

http://www.gotmead.com/forum/showpost.php?p=160786&postcount=2

 

[Jim H]

Point taken. Thank you for the help. Potassium bicarbonate should be here by end of week, and I will try out the dosage you recommend. Until then, I will degas it every day to help keep it from getting too out of hand.

BTW: is the dosage determined given the current pH, by the concentration of honey, or by the total volume/rule of thumb? In essence, for my next batch, how do I judge how much to put in to *prevent* this from happening?

 

[kchaystack]

I would not add it unless you need it. You should test the pH every so often, and adjust as needed.

 

[rmccask]

I think the amount needed, if any, depends on the ph/buffering in your ingredients (mostly the honey and water). I had been using cheap bottled spring water and honey from Costco for my first 3 batches and I needed something to keep the must from turning acidic on me like yours did. If you look at this thread, http://forum.northernbrewer.com/viewtopic.php?f=8&t=40912&sid=9173dceeecd2e11c47ae6a7e23b36edd, there is a discussion including wayneb and Hightest about using it as a pH buffer and they even throw around the dosage I use which probably influenced my decision at the time.

When I buy a good pH meter, I may stop automatically adding the potassium bicarbonate but for now it works for me.

 

[Jim H]

Got the potassium bicarb today. My scale cannot accurately measure the amounts needed. The label said that 1 tsp = 6g, so I measured out a slightly short 1/8 tsp per gallon, roughly 0.6 or so g/gal.

It didn't dissolve completely despite lots of stirring. Note to self- pre-dissolve first in some water next time.

Will check later today to see if the pH rose at all.... though the pH paper is very hard to read at lower pHs. The damp paper seemed darker orange than the dry paper, which is kind of hard to interpret. Note to self - get a frigging pH meter!

More details here.

 

[kchaystack]

You always read ph paper wet. Give it a few seconds after you apply the test liquid and read then. It is normal for it to change color as it dries.

 

[Jim H]

Yeah, well, this is the type that I have, and frankly it is very hard to read for the range I need. My saliva will read yellow-ish when the paper is wet. Water from my tap is darker orange, the color of the paper itself just about, which reads like pH 4. (NYC tap water is 6.8 or thereabouts, and not that low.) The must reads slightly darker than the paper, so somewhere around 3 or below... sort of like my tap water.

I have just ordered wine-range papers.

Hey! I can still edit this. To clarify, here is a pic of three tests. The first is the must, the second is NYC tap water, the third is my saliva. All are moist strips with excess liquid shaken off.

 

[Jim H]

Pic - Healthy looking (re-)starter

Just a few afters preparation, the starter looks like it's kicking in nicely. After this pic, gave it a shake to degas and mix in more oxygen.

 

[Jim H]

Another

The starter is frothing up.

 

[Jim H]

Potassium bicarbonate is weird sh*t. I was expecting it to be somewhat soluble in water. In practice, it isn't.

As an experiment, I tried mixing it into water, room temp, in a plastic measuring cup. I ended up with a little bit in solution (the water turned cloudier) but most of it stubbornly ended up as pellets on the bottom, and floating on the top as a powdery skim. It also increases surface tension by a bit... the powdery skim was crawling up the sides of the measuring cup by a lot.

How the heck do I get this stuff to dissolve into my mead and do its job? Arrrgh!

 

[UKTony]

I'm not the most scientific person I'm afraid, I needed to raise the pH on my current batch and just measured it and sprinkled it right in, I didn't pre-mix or anything... it may (or may not) be frowned upon, but it did exactly what I needed it to after a jolly good thrashing with the lees stirrer.

Tony