Some Rum mash troubleshooting...

[Guerilla Distillah]

Hey Rummy's,

So I have been having difficulty my last couple of stripping runs on Molasses washes. I have not been able to take starting gravities as I do not own a brix refractometer... a deficiency I will correct on Monday when I order one. But I have been fermenting things for a very long time and it's not difficult to know when for mentation is complete. So when I thought my mash was complete I went ahead with my normal stripping run procedures and instead of a 3 to 4 hour run it ended up being a 90 minute run both times in a row and I got a relatively low yield. It went from initial ABV percentage down to 20% ABV far more quickly than ever before. My current batch stop showing signs of fermentation after three days and my pH dropped to around 3.9. I have about 30 gallons of wash and I want to make certain I am going to get my expected healed from at this time. Any suggestions on what I should do next to ensure I have fermented out all of the sugars I added initially? It was about 30 gallons of water to 5gal Molasses( fancy food grade, not blackstrap feed grade)plus 18lbs cane sugar. At this point, my plan is to hold off my stripping run until after I get my refractometer. But of course, that will only give me a final gravity and not any indication of my starting gravity with us ABV of finished wash. Thoughts?


Thx
GD

[Stargazer14]

You dont have a hydrometer to take your final gravity? I make a lot of rum but honestly never really worried about my OG, one,
you cant measure it with the hydrometer as the molassas is so thick with other stuff,
and two, I just roughly figure it out based on the sugars and amount of molasses I used.
I was never too concerened about my OG, as long as I wasnt going over on the sugars and giving my yeast a hard time.
It doesnt sound like you over worked your yeast on sugar, tho you might want to throw a few oyster shells in there.

And tho I am lax on checking OG, I certainly do not run anything until I check the final gravity after my fermentation is (hopefully) complete.
If its not, I check my pH, fix if needed and maybe put in another pinch of yeast. I have had a few rums stall and some took weeks to finish, but all have turned out wonderful.

I guess I'm just surprised that if you can afford and order a refractometer that you would not have the $6 hydro to see if the fermentation is finished.

(sorry if that sounds like I am being a smart ass, I am not, it just sounds that way!)

So my suggestion would be cancel the brix order and buy a half dozen hydrometers!

[Guerilla Distillah]

Ok, I have SEVERAL hydrometers... but what good is taking a reading with a device that doesn't read accurately if there are unfermented solids left? The final gravity reading only has context if you have an original gravity reading. Because we all know there's no chance of fermenting back to 1.000... so while, yes, it did come off a LITTLE smart assed, i'm more concerned about solving my problem then preserving my feelings. Tried adjusting my pH with pickling lime, and saw no change in readings. And before you ask, yes I trust my calibrateable Ph Pen.


Thx

[Stargazer14]

(again, sorry if I sounded 'smart assed')

Having the hydrometer reading will let you know if it is done - even with unfermentables (which tend to settle). If you get a reading down near 0 you will of course know its finished.
(you can also go by taste)

I never had a final high reading on the hydro even with the unfermentibles, so I would just go by the hydrometer. And I use LOTS of molasses.

[HDNB]

at first i thought you have 5 lbs of molasses, but i re-read 5 gallons, which would put you in 14-15% potential territory.
ph and nutrient should not be the problem. stressed yeast maybe if you got a shit batch...did you proof the yeast? did you heat this mixture and pitch yeast too hot?
temperature maybe an issue.
i never had problems with sugar ferments so other than these things, it beats the shit outta me. i also never heated sugar washes at all. learned my lesson pitching too hot on AG's.

hydrometers are valid on molasses, and more times you do it the more the information gathered will help. What i mean is if you have an OG at 15% and it finishes at 3 you have a net gain of 12% ... and then the next one you start at 12 and finish at 3 for a net gain of 9....you will know what to expect on future washes of similar proportions.

oh yeah, i'd OG in at 10-12% on molasses but you prolly already knew that.

[Guerilla Distillah]

I TOTALLY get what yer sayin on the knowledge through repetition and observation. Much appreciated input.

DG

at first i thought you have 5 lbs of molasses, but i re-read 5 gallons, which would put you in 14-15% potential territory.
ph and nutrient should not be the problem. stressed yeast maybe if you got a shit batch...did you proof the yeast? did you heat this mixture and pitch yeast too hot?
temperature maybe an issue.
i never had problems with sugar ferments so other than these things, it beats the shit outta me. i also never heated sugar washes at all. learned my lesson pitching too hot on AG's.

hydrometers are valid on molasses, and more times you do it the more the information gathered will help. What i mean is if you have an OG at 15% and it finishes at 3 you have a net gain of 12% ... and then the next one you start at 12 and finish at 3 for a net gain of 9....you will know what to expect on future washes of similar proportions.

oh yeah, i'd OG in at 10-12% on molasses but you prolly already knew that.

[Stargazer14]

You wrote -'So when I thought my mash was complete' - what was it that made you think it had completed?

I ask because I read many people talking about how their rum finished in 3 or 5 days, this amazes me as my ferments go for weeks,
not that I mind, I'm a very patient person, the long ferments have been good to me, and they do sit rather cool (75º) as opposed to the tropical 90º ferments.

So I can imaging people thinking 'if all my other washes finished in a week, this one must be done too', when in fact it needs another 2 weeks.

[rgreen2002]

...Might not be a wash problem....

If you are "losing" alcohol (i.e. getting less than you expect) consider a leak during distillation as a worst case scenario. Much more important problem than a short ferment! Be sure to run your system and check.

[Guerilla Distillah]

Gonna go with Occam's razor on this one. Only leak I've had has been a crack in my steam jacket. Convinced it's fermentation related. Went got some powdered oyster shells and sprinkled in about a Cup. Within 30 seconds there was an ominous "krausen" building and I realized a serious possibility of overflow!! Quickly siphoned into clean pail until the reaction slowed. Going to treat myself to an afternoon snack tomorrow of fresh oyster shooters and clean the shells really well and suspend them in my wash. Pitched fresh yeast about half hour ago. Fingers crossed for signs of life. Gravity reading on my hydrometer was 1.070...

...Might not be a wash problem....

If you are "losing" alcohol (i.e. getting less than you expect) consider a leak during distillation as a worst case scenario. Much more important problem than a short ferment! Be sure to run your system and check.

[shadylane]

Went got some powdered oyster shells and sprinkled in about a Cup. Within 30 seconds there was an ominous "krausen" building and I realized a serious possibility of overflow.......
...........Fingers crossed for signs of life.

If adding oyster shell caused it to foam up.
It was still actively fermenting
I think the proper big word for that is nucleation
https://en.wikipedia.org/wiki/Nucleation" onclick="window.open(this.href);return false;" rel="nofollow

[Guerilla Distillah]

Thanks Shady, me likem big words. Just checked my Ph...4.3 my only issue with the "active fermentation" theory is I get NO activity in my airlock. None, not even a sign of positive pressure.

GD

[shadylane]

Sounds like a CO2 leak

[Guerilla Distillah]

Hadn't really thought of that. Just re-seated the airlock stopper... I'll check in an hour.

GD

[NZChris]

I've had a refractometer for twenty years, but never bothered to use it on rum except to check the brix at the start to compare it to previous ferments. Beyond that it would be useless.

The only way I manage, is by calculating the total amount of fermentable sugars in the wash and the expected drop in SG, then taking the OG. That gives me a ballpark FG to expect. When the SG hasn't dropped for 24 hours it's dead and no amount of flogging will revive it.

Don't be greedy. At an 8% abv target, it should ferment out with no trouble unless you have been adding a lot of dunder that is high in non-fermentables.

Check the abv of your dunder and allow for it in your calculations if you are using a lot, as it adds to the OG and to the osmotic pressure on the yeast.

[shadylane]

Hadn't really thought of that. Just re-seated the airlock stopper... I'll check in an hour.

GD

What cha fermenting in

[Guerilla Distillah]

35gal food grade poly drums. Rubber sealed screw tops. I cut hole for bung with hole saw. 3/4 dump valve about 2" off bottom to leave lees behind. Same vessel for Dunder Pit but valve is 18" off bottom for drawing clean Dunder

GD

Hadn't really thought of that. Just re-seated the airlock stopper... I'll check in an hour.

GD

What cha fermenting in

[shadylane]

35gal food grade poly drums. Rubber sealed screw tops.

Sound like leaks are unlikely on the drum and 2 screw tops.
What Ya using to stick the bubble trap into drum bunghole
Maybe a cork pushed into a threaded plastic hole

[Guerilla Distillah]

HEY HEY!!!! I've got bubbles!!!! I think the Ph buffer may be my huckleberry... thanks for everyone's input

GD

[shadylane]

Glad the oyster shells helped
Maybe try using boiled yeast, oyster shells and other nutrients on the next ferment for comparison.

[Yummyrum]

LOL , I'd say you just got a good seal when you screwed the lid on this time . I think those screw top fermenters with the foam rubber seal suck big time .For me they are a PITA to tighten enough to seal.Prefer the clip on lid jobbies ...never had an issue with them .
What ever the reason , glad to hear its bubbling again .

My tuppence on Reflectometers is that they are no better for Rum than Hydrometers despite some folk thinking they have the magical ability to measure fermentable sugar only and ignore the unfermentable crap . This is Bollocks . Hydrometers use buoyancy where as Reflectometers use refractive index .....both are directly related to the density of the sample they are in regardless what makes up the consistency of the sample.
Having said that a fruit wash may consist of a mix of juice and pulp . In this case a drop of juice in a Reflectometer will give a truer reading as its targeting the sugary liquid . In a Rum wash with Molasses , we can't physically extract such a specific sample as its all dissolved together .

Also best way to tell if a Rum wash is done is to taste it . Still sweet , not done . Tastes as bitter as twisted Nun , its done

[Saltbush Bill]

I'd say you just got a good seal when you screwed the lid on this time . I think those screw top fermenters with the foam rubber seal suck big time .For me they are a PITA to tighten enough to seal.

+1

In a Rum wash with Molasses , we can't physically extract such a specific sample as its all dissolved together .

+1

best way to tell if a Rum wash is done is to taste it . Still sweet , not done . Tastes as bitter as twisted Nun , its done

Why does every one need to complicate things so much Yummy .....Rum is one of the easiest things to make if you use the KISS principal.
Taste buds were made for tasting washes ,,,god gave us fingers to dip into wash so we could taste it. I haven't used a hydrometer in years.

[johnnyv]

You wrote -'So when I thought my mash was complete' - what was it that made you think it had completed?

I ask because I read many people talking about how their rum finished in 3 or 5 days, this amazes me as my ferments go for weeks,
not that I mind, I'm a very patient person, the long ferments have been good to me, and they do sit rather cool (75º) as opposed to the tropical 90º ferments.

So I can imaging people thinking 'if all my other washes finished in a week, this one must be done too', when in fact it needs another 2 weeks.

Using an aquarium heater set at 30C I get 98-99% of the total SG drop within 48 hours.
Providing I have sufficient live yeast and pH buffering calcium carbonate and I don't go much above 1.095 SG initial where the yeast start getting a bit retarded.
This talk of airlocks seems funny to me as I can't imagine being able to use one the ferment is so violently fast.

[The Baker]

johnnyv said, "Using an aquarium heater.... "
Hi, Johnny,
I use them, too.
But some say they do not warm the bottom of the fermenter very well.
So...
I will hang them in some ordinary downpipe, 90 cm I think. (I already have some).
The pipe will sit on the bottom of the fermenter. But there will be sediment, so I will use my drill and a big spade bit to cut holes a bit further up.
The pipe will finish somewhat below the top of the liquid...this is a bit high-tech and I have not decided yet.
Then to move the convection current (well, gentle movement) away from the immediate vicinity of the downpipe, above the holes I plan to insert the downpipe through the (surplus) lid of a ten or twenty litre bucket.
Please feel free to use my plan, I don't intend to patent it ( !!!! ) but I really do think it will work well.

Geoff

[Pikey]

You wrote -'So when I thought my mash was complete' - what was it that made you think it had completed?

I ask because I read many people talking about how their rum finished in 3 or 5 days, this amazes me as my ferments go for weeks,
not that I mind, I'm a very patient person, the long ferments have been good to me, and they do sit rather cool (75º) as opposed to the tropical 90º ferments.

So I can imaging people thinking 'if all my other washes finished in a week, this one must be done too', when in fact it needs another 2 weeks.

Using an aquarium heater set at 30C I get 98-99% of the total SG drop within 48 hours.
Providing I have sufficient live yeast and pH buffering calcium carbonate and I don't go much above 1.095 SG initial where the yeast start getting a bit retarded.
This talk of airlocks seems funny to me as I can't imagine being able to use one the ferment is so violently fast.

You're knocking up 14 % abv in 48 hours ???? - Please educate me

[Yummyrum]

You wrote -'So when I thought my mash was complete' - what was it that made you think it had completed?

I ask because I read many people talking about how their rum finished in 3 or 5 days, this amazes me as my ferments go for weeks,
not that I mind, I'm a very patient person, the long ferments have been good to me, and they do sit rather cool (75º) as opposed to the tropical 90º ferments.

So I can imaging people thinking 'if all my other washes finished in a week, this one must be done too', when in fact it needs another 2 weeks.

Using an aquarium heater set at 30C I get 98-99% of the total SG drop within 48 hours.
Providing I have sufficient live yeast and pH buffering calcium carbonate and I don't go much above 1.095 SG initial where the yeast start getting a bit retarded.
This talk of airlocks seems funny to me as I can't imagine being able to use one the ferment is so violently fast.

You're knocking up 14 % abv in 48 hours ???? - Please educate me

Pikey , I'm guessing johnnyv is talking Rum here and not sugar washes . Not sure where you get 14% from ?
Plugging in 1.095 and ending at 1.000 gets me under 12.5% ABV and assuming it is Rum , it probably is a Sugar /Molasses wash and with Dunder it is likely to finish at around 1.020 which is under 10% ABV .

At 30 degC ,its quite doable I think. Even My all molasses washes which have a start gravity over 1.120 and end around 1.060 ish will be mostly ( and I agree here with Johnny 98-99% total drop ) all over in 2 days .......again the high fermentation temperature is the key here

[johnnyv]

Pikey , I'm guessing johnnyv is talking Rum here and not sugar washes . Not sure where you get 14% from ?
Plugging in 1.095 and ending at 1.000 gets me under 12.5% ABV and assuming it is Rum , it probably is a Sugar /Molasses wash and with Dunder it is likely to finish at around 1.020 which is under 10% ABV .

At 30 degC ,its quite doable I think. Even My all molasses washes which have a start gravity over 1.120 and end around 1.060 ish will be mostly ( and I agree here with Johnny 98-99% total drop ) all over in 2 days .......again the high fermentation temperature is the key here

This is correct, final SG for a molasses + partial sugar wash is 1.016 for me which is about 10.37% ABV.
All bran sugar wash starting 1.093 and getting to 1.004 at about 72 hours is about 11.68% ABV.
I get close to 8% potential in 24 hours.

[Guerilla Distillah]

OK, it's me again. Well I was hoping it would rectify itself over time but my washer is still upwards of 1.090...WTF?? I finally got frustrated, and picked up 10 sachets of champagne yeast which, when I added to my peach and apricot washes Took off like a ROCKET...I awoke this morning to check in there is nary a bubble in the airlock. I am SUPER frustrated as this is over $100 worth of materials in the wash and I can't figure out why it won't ferment out. My pH is 4.4. ANY help? I simply don't want to throw it out and start over.


Thx
GD

[still_stirrin]

GD,

Try diluting, aerating a bit and repitching more (fresh) yeast. Also, make sure your temps are correct for the yeast strain you're using.

Seems to me like a lesson in following a Tried & True recipe would be less risky (and costly). But then again, "hindsight is 20/20".
ss

[Guerilla Distillah]

GD,

Try diluting, aerating a bit and repitching more (fresh) yeast. Also, make sure your temps are correct for the yeast strain you're using.

Seems to me like a lesson in following a Tried & True recipe would be less risky (and costly). But then again, "hindsight is 20/20".
ss

I did follow a tried and true recipe. That's why I am so flummoxed

[Shine0n]

Which one?
The pH is a tad low but not too bad, what temp are you fermenting at?
+1 SS With diluting and pitching fresh yeast.
I'd also take a drill and mixer and whip the shit out of it for aeration then pitch at with the temp appropriate for the yeast used.

If using bread yeast and your still around 75f I'd put an aquarium heater in it to keep temps higher around 90f

Shine0n