Fermentation Won't Start

[joshjacobsen]

Hi all,

I'm in the midst of attempting to ferment a Pinot Noir drum of my first frozen must but am now worried as I haven't been able to get fermentation to start. I know similar instances have been written about in these forums before but everything I've found seems to pertain to stuck fermentations that were already underway.

Relavent information is below, appreciate any help you can provide, thanks!

TIMELINE:
1) Picked up frozen drum at noon on December 29th, allowed to thaw until the late morning on January 1st (so not quite 3 days of cold soak)

2) Upon opening the drum (January 1st) to transfer to my fermentation vessel (a stainless steel 290L Speidel tank), I found that the contents were about 90% thawed, w/ the last 10% (kind of a firm slushy) being somewhat easy to separate for mixture into the thawed portion

3) My next step (still January 1st) was to add a 50ppm S02 dosage (powder form) assuming 50 gallons of must

4) After above S02 dosage, I then waited ~16 hours to inoculate. This is perhaps where I made a mistake as I'd been under the impression that 12 hours was enough time but I read later that 24 hours was recommended.

5) For inoculation (now January 2nd), I followed MoreWinemaking's directions on preparing a yeast starter. It consisted of Spring water (no chlorine but still containing minerals), GoFerm (1.25 grams to 1 gram of yeast), and RC212 yeast (8 packets of 5 grams, which at 40 total grams is less than I'd wanted for my 50 gallons of must but I'd make a miscalculation during my purchase process and didn't have as much as I'd wanted). Temperature at pitch was likely a bit colder than I'd have liked (low-mid 60's) but I'm not entirely sure as I'd broken my floating thermometer during sanitization and inexplicably didn't have any backup options (note that I was in the middle of ordering multiple means of measuring temperature as I didn't want to reply on any one tool). Regardless, I began raising the temperature of the room (via space heater) to a 68-70 degree (F) range.

6) Since inoculating on January 2nd, I've seen little to no signs of fermentation (it's now January 6th). Concerned that perhaps my original S02 dosage was still prevalent when I pitched my yeast/starter, I'd read that rigorous/frequent stirring could help dissipate it in route to kickstarting the fermentation. I've been doing that since January 4th but have had no luck. There's been more bubbles/foaming around the rim of the tank but I'm not sure if that's oxygen that I'd stirred in or C02 from fermentation (see attached picture, which is the way it's looked from January 4th to today, January 6th).

Per everything above, do I simply need to re-inoculate? If so, do I assume an entirely new/full dosage (this time at 50 grams)? If so, do I also do another yeast starter or is that too much GoFerm in the must? Note that once fermentation is underway, I plan to use Fermaid-O at recommended intervals.

Thanks all!

 

[sour_grapes]

It certainly looks to me like fermentation has started. "Houston, we have liftoff!"

 

[joshjacobsen]

Hi @sour_grapes, appreciate the response.

However, the image depicts what I've seen every day for the last 3-4 days (meaning nothing seems to be changing in terms of more bubbles/foaming or development of a cap). Would you continue to wait for changes and if so, at what point would you take different action (ie re-inoculating)?

Thanks!

 

[mainshipfred]

I think it's going also, have you taken a gravity reading lately? RC212 is a low foaming yeast.

 

[stickman]

I agree with @sour_grapes It looks like fermentation has started. The must temperature may have been a bit low based on your timeline. RC212 likes a slightly warm must starting temperature around 64F; you can get it going at cooler temps, but it requires delicate handling by making sure the yeast starter is no more than 10F different than the must. The perimeter is fermenting, because it is warmer there than in the middle.

 

[joshjacobsen]

I think it's going also, have you taken a gravity reading lately? RC212 is a low foaming yeast.

Hi @mainshipfred - haven't taken a gravity reading but that's a good idea, also wasn't aware that RC212 was a low foaming yeast so appreciate that insight.

 

[joshjacobsen]

I agree with @sour_grapes It looks like fermentation has started. The must temperature may have been a bit low based on your timeline. RC212 likes a slightly warm must starting temperature around 64F; you can get it going at cooler temps, but it requires delicate handling by making sure the yeast starter is no more than 10F different than the must. The perimeter is fermenting, because it is warmer there than in the middle.

Hi @stickman - Good points, you're probably right regarding the low starting temperature and there may have been more than a 10F difference between the yeast starter and the must.

 

[joshjacobsen]

All - is it safe to assume I should discontinue stirring to dissipate S02 based on my original theory of it being prevalent?

Also, given that the rate of bubble/foam formation has been slow to increase and I haven't seen any cap formation in 4 days, how long should I wait before some other action (ie re-inoculation) is taken?

Huge thanks for all your help/reassurance!

 

[mainshipfred]

I've never done a drum or anything close but after rereading your original post I have to pose a few questions others may be better to answer.
1. Is the drum crushed grapes or juice with some skins left in?
2. It is my understanding when making additions to the must you use the amount of wine expected rather then the initial volume of the must.
3. The must could have had S02 added initially so if your calc for added S02 didn't take into consideration any potential initial S02 you could be way over 50 ppm.
4. If you used the volume of must to calc the S02 addition rather then the wine you could be even higher.

Again, all this coming from a beginner so take it with a grain of NaCl.

 

[stickman]

@mainshipfred When it comes to so2 additions to the must, you typically use the total must volume, so I think he is ok there. You do bring up a good point regarding so2 addition by the supplier, that should be reviewed. With frozen must, the main issue is temperature, the cap should form when the must temperature gets up to around 65F or so.

 

[dralarms]

It certainly looks to me like fermentation has started. "Houston, we have liftoff!"

Correct

I think it's going also, have you taken a gravity reading lately? RC212 is a low foaming yeast.

Again correct, rc-212 is a low foam yeast, I use it sometimes but I use 71b-1122 the most. Or a hard to start one I'll hit it with ec-1118

 

[ceeaton]

Hey @joshjacobsen, I haven't seen a reading for your temperature, what's it at? Do you have any way, if it's in the low 60's to raise it up to around 70*F with that fancy fermenter you are using?

Edit: Nevermind, I just saw it embedded in your longer post. Just ignore me (like my wife) and I'll eventually go away!

 

[joshjacobsen]

I've never done a drum or anything close but after rereading your original post I have to pose a few questions others may be better to answer.
1. Is the drum crushed grapes or juice with some skins left in?
2. It is my understanding when making additions to the must you use the amount of wine expected rather then the initial volume of the must.
3. The must could have had S02 added initially so if your calc for added S02 didn't take into consideration any potential initial S02 you could be way over 50 ppm.
4. If you used the volume of must to calc the S02 addition rather then the wine you could be even higher.

Again, all this coming from a beginner so take it with a grain of NaCl.

@mainshipfred - answers to your question are as follows:

1. Frozen musts are comprised of crushed grapes and their respective juice, the drum is just the largest size (ie 50-55 gallons)
2. I was under the impression that S02 additions are made w/ the entire must volume in mind (given binding) and that other additions (ie Tartaric Acid) are made w/ the expected final wine volume.
3. I can confirm that there was no S02 added to the original must
4. See #2

Thanks!

 

[joshjacobsen]

@mainshipfred When it comes to so2 additions to the must, you typically use the total must volume, so I think he is ok there. You do bring up a good point regarding so2 addition by the supplier, that should be reviewed. With frozen must, the main issue is temperature, the cap should form when the must temperature gets up to around 65F or so.

@stickman - Thanks for confirming S02 dosage against total must volume vs. expected final wine volume. Reiterating that there was no S02 addition by the supplier.

Also, the room and tank temperature is between 65-70F, hence my concern regarding lack of cap forming.

 

[joshjacobsen]

Correct



Again correct, rc-212 is a low foam yeast, I use it sometimes but I use 71b-1122 the most. Or a hard to start one I'll hit it with ec-1118

Thanks @dralarms - this is my first time using rc-212 so I'm definitely taking these things into consideration in the future.

 

[joshjacobsen]

Hey @joshjacobsen, I haven't seen a reading for your temperature, what's it at? Do you have any way, if it's in the low 60's to raise it up to around 70*F with that fancy fermenter you are using?

Edit: Nevermind, I just saw it embedded in your longer post. Just ignore me (like my wife) and I'll eventually go away!

@ceeaton - Haha, i've got some non-fancy fermenters as well . Thanks for the input regarding temperature, I know you edited after you saw mention in my post but it's good to know I'm in the right range.

 

[joshjacobsen]

Reiterating my appreciation for everyone's input. I do want to make sure my last question doesn't get lost in the dialogue so repasting below:

"...is it safe to assume I should discontinue stirring to dissipate S02 based on my original theory of it being prevalent?

Also, given that the rate of bubble/foam formation has been slow to increase and I haven't seen any cap formation in 4 days, how long should I wait before some other action (ie re-inoculation) is taken?..."

 

[Scooter68]

Haven't seen anything about an updated SG reading? That is the only measurement that matters when trying to find out if fermentation is occurring. Some wines and yeast don't really foam much at all some combinations act like a washing machine with too much soap.
Until you take an SG reading and compare that with the original reading it's all just speculation.

 

[sdelli]

Haven't seen anything about an updated SG reading? That is the only measurement that matters when trying to find out if fermentation is occurring. Some wines and yeast don't really foam much at all some combinations act like a washing machine with too much soap.
Until you take an SG reading and compare that with the original reading it's all just speculation.

Totally agree!

 

[mainshipfred]

@mainshipfred - answers to your question are as follows:

1. Frozen musts are comprised of crushed grapes and their respective juice, the drum is just the largest size (ie 50-55 gallons)
2. I was under the impression that S02 additions are made w/ the entire must volume in mind (given binding) and that other additions (ie Tartaric Acid) are made w/ the expected final wine volume.
3. I can confirm that there was no S02 added to the original must
4. See #2

Thanks!

Thanks for clearing that up for me. A drum is more then I would like to make of a single wine but the the thread has intrigued me. If you don't mind, who did you get it from?