Where does banana flavor in Rum come from?

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Where does banana flavor in Rum come from?

Post by der wo » Fri Apr 06, 2018 9:49 am

I recently got a bottle of Forsyths White Rum (Worthy Park distillery) with a very high ester count. It differs from the other two high ester Rums (from Hampden distillery) I own, because of its incredible strong banana flavor. It's cleaner than Hampden, has less pineapple, but it has this strong obvious banana in the front of the flavor.

The perhaps most important difference in the production of those Rums is, that Hampden gets its esters by using infected dunder, but Worthy park doesn't use dunder at all, but let the ferment open for three months at tropical temps. I don't have a picture from their long ferments, but here is one of the Clarendon distillery fermenting open for one month for their Monkymusk Rum:
https://i0.wp.com/cocktailwonk.com/wp-c ... f-1156.jpg" onclick="window.open(this.href);return false;" rel="nofollow
Looks similar like heavily infected dunder.

The most obvious difference between an infected wash and an infected dunder is the ethanol concentration. Dunder has 0% and wash has 6-10%. The result is, that in opposite to the dunder the fermented wash feeds vinegar bacterias (they process ethanol to vinegar). A three months old open ferment will have a very high vinegar concentration, an old dunder almost zero. And when vinegar forms the ester with ethanol (ethylacetate), the distillate will have a glue smell.

Yes, the Forsyths has glue smell too, but the banana flavor is stronger.

Which chemical compounds are responsible for the banana? According different sources banana-esters are mostly from vinegar and higher alcohols (several amyl alcohols). They have lower odor thresholds than the glue-ester, so it needs only small amounts to notice them. But of course the more banana-esters the more banana flavor.
So what a banana smelling Rum needs is a vinegar infection (or added vinegar, many Rum producers simply add cane vinegar somewhere in the process) and much of those higher alcohols. For the added vinegar here a "proof picture" of the "acid tank" of Long Pond distillery: https://i2.wp.com/cocktailwonk.com/wp-c ... f-1156.jpg" onclick="window.open(this.href);return false;" rel="nofollow And you can read in the Arroyo papers something about.
There are a few circumstances, which promote the development of higher alcohols:
- hot fermentation
- high OG
An all molasses ferment in the tropics offers both. BTW, Worthy Park controls the fermentation temp to 30°C.
There are other circumstances, which also perhaps promote higher alcohols. But the sources are contradicting. For example adding yeast nutrients.

And then? In case the low odor threshold of the banana-esters is not enough competing against the glue smell? How get rid of too much of the glue smell but keep the banana flavor? Probably simply with the heads cut. The glue-ester has a much lower boiling point than the banana-esters. Worthy Park cuts 1-2% of the wash volume as fores/heads (200-400l fores/heads, 18000l wash). They have two thumpers filled with high abv feints and it looks like two plates over the second thumper. So it's a relative high distillation, what also means, that the glue smell is well concentrated, and then cutting 1-2% perhaps is enough to get a stronger banana than glue odor. Why not cutting more? I don't know. Speaking for my Forsyths bottle, I think it's good like it is. Generally I think: no glue smell -> no banana flavor.

Here the source of many of the numbers: http://cocktailwonk.com/2016/04/worthy- ... ntury.html" onclick="window.open(this.href);return false;" rel="nofollow

Here...
viewtopic.php?f=39&t=69155
...I wrote "the highest chance to get fusel-esters in a dominating amount is in the dunder pit. Because only here it's possible to have more fusel alcohols than ethanol (because fresh dunder contains almost zero ethanol, but probably many fusel alcohols). But the (fusel-) alcohol strength in dunder is very low for a good esterification rate. So when we use the dunder, it will contain much more acids than esters. And the acids will come in contact to the massive amount of ethanol sooner or later and will build ethanol-esters. Or how much could sulphuric acid help here? Perhaps adding sulphuric acid to dunder before adding the dunder to the low wines or wash gives the fusel-alcohols a head start? I don't know how effective the catalyst works under such bad circumstances (low (fusel-) alcohol strength)."
But looking at my bottle Fosyths, it seems to be very possible without dunder. But dunder still looks more promising for me (perhaps with added cane vinegar?). Unfortunately I cannot judge, how many esters from higher alcohols in my infected dunder esterified Hampden Rums are. I am only able to do this with the Forsyths Rum, because the vinegar-ethanol-ester (glue) smells much different from the vinegar-higher alcohol-esters (banana). The Hampden is more in direction butyric acid esters. And the different butyric esters all smell some kind of fruity. Between for example peach and pineapple (butyric esters) is less difference than between glue and banana.

And I wrote "But are the fusel-esters really needed? How many of you have ever tasted a high ester rum? This stuff is expensive. I only one (but often, I have a whole bottle, Habitation Verlier Hampden LROK). For me it smells possible, that almost only ethanol-esters come from the wash and the dunder, mainly ethyl acetate and ethyl butyrate."
Here my opinion has changed with the Forsyths Rum.

The goal of this post is to inspire the members, who run or plan an infection currently, to think a bit more about vinegar than butyric or lactic infections.

I am currently planing an all molly Rum, hot and long fermentation, playing with cane vinegar, dunder pits, triple Potstill distilled.

I don't know, which cane vinegar the Rum producers use. Probably the cheapest one. But is the cheapest one something industrial large batch tasteless distilled or something raw unfiltered? I have buyed a bottle of cane vinegar in an Asia shop. Tastes not very interesting. All cane vinegar I can get here is distilled. If it has a color, it's E150c. Pretty tasteless, wouldn't buy it again, no advantage over any other vinegar. Perhaps I will make molasses vinegar by myself.
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Re: Where does banana flavor in Rum come from?

Post by Single Malt Yinzer » Fri Apr 06, 2018 10:18 am

Der Wo wrote:A three months old open ferment will have a very high vinegar concentration, an old dunder almost zero.
I'm surprised there's any alcohol left after 3 months.

Der Wo already knows this, but for others, the Banana ester is Isomyl acetate (ester):
https://en.wikipedia.org/wiki/Isoamyl_acetate" onclick="window.open(this.href);return false;" rel="nofollow
Isoamyl acetate, also known as isopentyl acetate, is an organic compound that is the ester formed from isoamyl alcohol and acetic acid.
Isoamyl is a secondary alcohol that expresses in the tails (Fusel Alcohol):
https://en.wikipedia.org/wiki/Isoamyl_alcohol" onclick="window.open(this.href);return false;" rel="nofollow
https://en.wikipedia.org/wiki/Fusel_alcohol" onclick="window.open(this.href);return false;" rel="nofollow
Der Wo wrote:The goal of this post is to inspire the members, who run or plan an infection currently, to think a bit more about vinegar than butyric or lactic infections.
:thumbup: I wonder has anyone directly spiked their rum ferment with a vinegar as a test? If so what kind of vinegar, how much, and what were the results?

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Re: Where does banana flavor in Rum come from?

Post by der wo » Fri Apr 06, 2018 12:14 pm

Yes, I also wonder if or why alcohol is left after 3 months. Perhaps the pellicle hinders oxygen to enter the wash? No oxygen, no further vinegar development. Or perhaps, if we have a vinegar infection, we only think it's complete transformed to vinegar, because the smell is of vinegar is much stronger than of alcohol?

Yes, isoamyl acetate (= isopentyl acetate) is probably the most important one. But AFAIK also isomeres of it have similar flavors. This is why I didn't write it.

I haven't read that a homedistiller has poured vinegar in a wash. I will do it. But in Germany it's too cold in april for a hot Rum ferment. I will wait two months. Queue jumping allowed.
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Re: Where does banana flavor in Rum come from?

Post by Saltbush Bill » Fri Apr 06, 2018 1:40 pm

der wo wrote: let the ferment open for three months at tropical temps.
I also picked up on this straight away, in a tropical climate an open fermenter would loose a lot of alcohol in 3 months, Id be surprised if there was anything left to distill.
Maybe I'm wrong , Ive never left a large ferment open that long to find out.
der wo wrote:I am currently planing an all molly Rum, hot and long fermentation,
What yeast do you propose to use that will let you achieve both? Hot and long don't fit well together when it comes to yeast and fermentation.
30c is not hot for a rum ferment from what I have read and from my own experience.

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Re: Where does banana flavor in Rum come from?

Post by raketemensch » Fri Apr 06, 2018 1:55 pm

I’ve got a very vinegary-tasting rum wash right now. It was made with feed molasses and jaggery (raw Indian sugar), and it just never took off. My thought is that there were just too many sugars for the yeast, and it was overcome.

It’s 30 gallons, so I’m going to experiment with it once it warms up a little as we get into Spring. I’m going to dilute it, and leave it open and see what happens. Worst-case I get some run infections to play with, but best-case I’ll get some of that banana flavor. My plan was to distill it with 15-20 bananas in the keg anyway.

I used some wit yeast that has been bred to produce banana esters a few times, but I’ve never tried it with rum.

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Re: Where does banana flavor in Rum come from?

Post by Yummyrum » Fri Apr 06, 2018 3:41 pm

I don't know where it comes from derwo but I know I used to get a lot of banana flavour in my pot stilled rum . I usually have my rum wash sittng around for weeks often over a month before I get around to distilling it so maybe that has something go do with it . Can't say I ever picked up any vinegar notes n the wash either .
To me the Banana seemed promenant in early heads .

Off topic but
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Re: Where does banana flavor in Rum come from?

Post by thecroweater » Fri Apr 06, 2018 6:54 pm

Same and particularly if the wash stalled or struggled so I put it down to esters from highly distressed yeast. I found the same thing tasting one of the expressions of Penderyn welsh whisky and thought it was bloody awful, looking into their still and process I think it might be a case of alcotec (turbo) yeast ran hot and fast, so again highly distressed yeast. Rum is not bad with some of those tropical fruit type flavours and running hot and fast is not necessarily a bad thing to get a little complexity into wash with such an overpowering main ingredient as it molasses. It is one of a number of reasons I don't run 100% molasses washes as they give a good strong molasses flavour with about
Zero complexity to them. Some guys prefer that style and some like a hint of this or that including slight fruit flavours which tend to mellow out over time.
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Re: Where does banana flavor in Rum come from?

Post by SaltyStaves » Fri Apr 06, 2018 9:23 pm

For my current rum project, I decided to try adding banana bread to a second gen feed grade molasses rum wash. I used a recipe that didn't have baking soda and it came out very underbaked and contained too much butter.
I then made the mistake of adding the banana bread to the Lees with a little bit of water while I stripped my gen 1 wash for some dunder. Three days into fermentation with half the sugar converted, the vinegar infection took hold. Bananas are an excellent source for Acetobactera and I had (unwittingly) let it take over.

I put the infected wash aside and covered it with some muslin cloth. Half of it went into an empty, open (muck) pit. It was far too acidic for anything to further infect it. It developed acetone aroma and then started to smell more like molasses again. I then drew some of it off and added hydrated lime to the rest (for putrefactive bacterial development). I have enough of it put aside that I can acidify the pit and keep it dormant over the winter.

When adding a few drops of H2SO4 to a sample of my low wines, muck and the acetic wash, I get a strawberry aroma. Its not unpleasant, but I'd certainly prefer to get some banana coming back.

Too rums I get strong banana aroma from are Mount Gay Black Barrel and Appleton 8 Year old. Neither of which are made with muck.

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Re: Where does banana flavor in Rum come from?

Post by thecroweater » Fri Apr 06, 2018 10:13 pm

Anything you added the acetic infection to is fubar, you can't use it for anything but to make vinegar. You can't "out ferment" it as it will work symbiotic with the yeast. Scrub and sanitize everything or this will be an on going situation.
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Re: Where does banana flavor in Rum come from?

Post by SaltyStaves » Sat Apr 07, 2018 12:04 am

thecroweater wrote:Anything you added the acetic infection to is fubar, you can't use it for anything but to make vinegar. You can't "out ferment" it as it will work symbiotic with the yeast. Scrub and sanitize everything or this will be an on going situation.
Its for dunder/muck. The infection is long gone. The acetic acid remains.

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Re: Where does banana flavor in Rum come from?

Post by der wo » Sat Apr 07, 2018 12:25 am

Saltbush Bill wrote:
der wo wrote: let the ferment open for three months at tropical temps.
I also picked up on this straight away, in a tropical climate an open fermenter would loose a lot of alcohol in 3 months, Id be surprised if there was anything left to distill.
Maybe I'm wrong , Ive never left a large ferment open that long to find out.
der wo wrote:I am currently planing an all molly Rum, hot and long fermentation,
What yeast do you propose to use that will let you achieve both? Hot and long don't fit well together when it comes to yeast and fermentation.
30c is not hot for a rum ferment from what I have read and from my own experience.
Yes. You know where to put your fingers that it pains... :lol:
I don't know. Perhaps it's all a bit more complicated:

Worthy Park (Forsyths): http://cocktailwonk.com/2016/04/worthy- ... ntury.html" onclick="window.open(this.href);return false;" rel="nofollow
Worthy Park makes two primary rum styles, light and high ester. The lighter style ferments in all four fermenters for thirty hours, and is temperature controlled by heat exchanger units that keep the mash at around 30 degrees C (86 degrees F). At the end of fermentation, the mash has an ABV of approximately 8.5 percent.
In contrast, the high-ester mash uses only two fermenters, takes about two to three weeks to complete, and isn’t temperature controlled. The resulting rum has an ester level of around 900 PPM, more than funky enough. The ABV of the high-ester mash is considerably lower than the 8.5 percent of the light rum. That is, what you gain in flavor, you give up in total ethanol. We heard the same explanation of esters vs. alcohol content at several other distilleries as well.


But when you search for Forsyths, all say it's fermented 3 months, not "about two to three weeks"...


Clarendon (Monkymusk): http://cocktailwonk.com/2016/03/inside- ... ptain.html" onclick="window.open(this.href);return false;" rel="nofollow
The molasses for the lighter rum is fermented for a relatively short time in twenty-four open-air metal fermentation tubs.
Molasses destined for heavier rum spends significantly more time fermenting, starting with a several week stay in excessively “rustic,” open-air wooden fermentation tanks covered with a picturesque layer of what seems to be fungus and mold. A thick layer of bio-mass floats on top of the mash. The heavy-rum mash then spends additional time in the aforementioned metal tanks, fermenting for about a month in total.


So why does the yeast produce higher alcohols at high temps? Does the yeast have to be stressed? So better using a yeast for 15-20°C and stress it with 30°C? Or is heat tolerant bakers yeast, which wouldn't have much stress with 30°C, all fine?

Hot and long fit well I think. But of course only the first 48h are an active alcohol fermentation.
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Re: Where does banana flavor in Rum come from?

Post by der wo » Sat Apr 07, 2018 12:29 am

raketemensch wrote:I’ve got a very vinegary-tasting rum wash right now. It was made with feed molasses and jaggery (raw Indian sugar), and it just never took off. My thought is that there were just too many sugars for the yeast, and it was overcome.

It’s 30 gallons, so I’m going to experiment with it once it warms up a little as we get into Spring. I’m going to dilute it, and leave it open and see what happens. Worst-case I get some run infections to play with, but best-case I’ll get some of that banana flavor. My plan was to distill it with 15-20 bananas in the keg anyway.
Dangerous. An unhealthy fermentation plus an infection.
I would try to calculate, if it's really too much sugar.
Starting an healthy ferment and then introducing the infection seems logical and is according to Arroyo also the traditional way.
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Re: Where does banana flavor in Rum come from?

Post by der wo » Sat Apr 07, 2018 12:49 am

Yummyrum wrote:I don't know where it comes from derwo but I know I used to get a lot of banana flavour in my pot stilled rum .
Compared to what?
SaltyStaves wrote:Too rums I get strong banana aroma from are Mount Gay Black Barrel and Appleton 8 Year old. Neither of which are made with muck.
If the Forsyths WPE has 10 banana, the Hampden LROK has 5, and Mount Gay XO or Appleton 12 perhaps have 2 banana. IMO

For me this thread is not like "How to get enough banana into my Rum" or "This is why your idiots shitty Rum lacks of banana flavor" :lol:
It's more about trying to go extreme in this direction and learn something perhaps and then deciding to go back perhaps, because Rum isn't only banana flavor.
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Re: Where does banana flavor in Rum come from?

Post by der wo » Sat Apr 07, 2018 1:05 am

thecroweater wrote:It is one of a number of reasons I don't run 100% molasses washes as they give a good strong molasses flavour with about Zero complexity to them.
So adding sugar to the ferment rises the complexity? :problem:
We can discuss it again and again (perhaps next time in the "Croweater rum wash"-thread? :lol: ). I think adding sugar is diluting the flavor. And if the flavor of an 100% molasses wash is too strong, I would distill it higher. It's better to concentrate the good flavors and strip out the bad ones with high distillation than to dilute both the good and bad flavors by adding sugar.
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Re: Where does banana flavor in Rum come from?

Post by SaltyStaves » Sat Apr 07, 2018 1:37 am

der wo wrote: If the Forsyths WPE has 10 banana, the Hampden LROK has 5, and Mount Gay XO or Appleton 12 perhaps have 2 banana. IMO
I'd love to try them then. Shame I can't get them locally, but I'll be in the UK later in the year, so it may be a good chance to sample them.

I can't speak for the Mount Gay XO, but I can tell you that Appleton 12 is nothing like the 8. The 8 has a lot of Banana and I much prefer it over the 12.

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Re: Where does banana flavor in Rum come from?

Post by thecroweater » Sat Apr 07, 2018 4:46 am

@ der wo
that might be the first thought that may jump to mind and if using refined sugar maybe so but by adding raw sugar you are more or less recreating something like the initial cane juice. I have made a cachaca type product using only muscovardo sugar and diluted is not a term I would use to describe that. My main point was if one flavour overpowers all others then you will very surely loose complexity, that's just plain logic. My point was by toning down the blackstrap flavour you will allow more subtle flavours to become detectable and that argument is also simple logic. Stripping out more favour of a molasses heavy flavoured rum will not bring out more subtle flavours but in fact will only serve to further decrease them until molasses is not just the strongest flavour but the only flavour. Now if it's a bannna flavour you want to remove leaving a stronger (than banana) flavour higher abv stripping will be your measure. Molasses is a very robust flavour, more so than most and does not very easily strip out so more often than not it's the last flavour standing. Now it's
true I add raw (turbinado) sugar but this is a very different product than brown sugar, there is a lot more going on there than molasses and sugar like for starters most of the compounds and flavours pre-stripped out of molasses and that is what is lost on so many ppl. All some hear is added sugar "aaah a whitch burn him" rather than think about the fact that by using raw sugar you are really adding back those compounds removed from the molasses. You can buy molasses stripped solely from raw sugar and it has a different brix and flavour than stock feed/blackstrap molasses because it has compounds removed from blackstrap but it is certainly not diluted.
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Re: Where does banana flavor in Rum come from?

Post by thecroweater » Sat Apr 07, 2018 4:52 am

SaltyStaves wrote:
thecroweater wrote:Anything you added the acetic infection to is fubar, you can't use it for anything but to make vinegar. You can't "out ferment" it as it will work symbiotic with the yeast. Scrub and sanitize everything or this will be an on going situation.
Its for dunder/muck. The infection is long gone. The acetic acid remains.
It won't be gone anywhere it would have just ran out of alcohol to convert, stuff is bloody resilient and will lay in wait as long as it takes, mother of vinegar is an evil bitch.
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Where does banana flavor in Rum come from?

Post by raketemensch » Sat Apr 07, 2018 6:44 am

der wo wrote: Dangerous. An unhealthy fermentation plus an infection.
I would try to calculate, if it's really too much sugar.
Starting an healthy ferment and then introducing the infection seems logical and is according to Arroyo also the traditional way.
I just have a really hard time calculating the sugar amounts with molasses. I went with what had worked earlier with this same brand of molasses, but the jaggery introduced even more unknowns.

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Re: Where does banana flavor in Rum come from?

Post by der wo » Sat Apr 07, 2018 8:04 am

I don't know, how tough the bacterias are. And if vinegar bacterias are more or less tough than for example lactic or butyric bacterias. All I can say is, that up to now I had no problems using the same fermenters for infected and uninfected batches. I clean with boiling water and a bit sodium hydroxide. Pouring it to the walls into the fermenter and brush it a bit. Either this cleaning procedure is safe enough or there is simply not enough time for the bacterias to take over my normal batches with normal fermentation durations.
Edit: I think, on any fruit I ferment are way more vinegar bacterias than in my fermenters after cleaning.

And as I wrote before, I doubt that a vinegar infection eats all the ethanol without pumping in air within 1 or 3 months, as long the wash has a pellicle.

Sugar or not sugar is off-topic. I don't want to debate it further. At least not in this thread.
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Re: Where does banana flavor in Rum come from?

Post by OtisT » Sat Apr 07, 2018 11:29 am

Great timing on this thread. I am in the process of chasing the banana too, and can try a test using Vinegar and/or sulfuric acid. Right now, my home smells of ripe banana having just stripped some rum. :-)

My last two batches of rum have an incredibly strong banana smell after the first pot distillation. Unfortunately, the banana smell was gone after the spirit run. I saved a few jars of the single run rum and most, but not all, of that banana smell simply disappeared after 4 or more days of airing. This rum used infected dunder in the ferment (boiled first in the first batch, live infection in the second.) Both were a brett lacto infection, so I am told.
Dunder only made up about 6% of the total ferment volume. Details on these are in the thread "High Ester Rum".

Note about my specific infection. I have the same infection in my Bourbon backset and I have never gotten Banana smell from stripping it. Based on this, I am guessing that the infection has nothing to do with my banana smell. Yes, it could be infection byproducts in combination with different alcohols (due to different ferment types) and my next tests should help prove this out one way or the other.

I have enough molasses/sugar for another 30 gallon ferment, and that gives me three or four boilers full to play with. I am planning to do my next rum ferment using the same recipe only with no dunder, so I have some "normal" rum to compare my High Ester rum to. Here is my test plan for this next non-dunder ferment:

I will have fresh dunder and feints from my previous rum to use.

Test 1) One normal strip (no additives). I want to see if I get Banana after a strip from the same ferment (minus the dunder.) I am guessing not, but I may be surprised. (Save low wines for later.)
Test 2) Do a single run rum using fresh dunder/feints in my thumper. Because I lost banana after a second distillation, and assuming dunder is necessary for banana, I want to try with dunder/feints in my thumper so hopefully I will get the banana because I would be making that ester in the thumper (only one distillation of that ester.)
Test 3) Assuming tests 1 and 2 confirm that Dunder is a necessary ingredient to get banana, I will repeat test 2 again but using vinegar/feints as opposed to dunder/feints in the thumper.
Test 4) Same as three, but use Sulfuric acid rather than vinegar.

Does this seem like the way to test this? Please let me know if/where I should make changes to this test plan.

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Re: Where does banana flavor in Rum come from?

Post by SaltyStaves » Sat Apr 07, 2018 1:34 pm

thecroweater wrote: It won't be gone anywhere it would have just ran out of alcohol to convert, stuff is bloody resilient and will lay in wait as long as it takes, mother of vinegar is an evil bitch.
Acetic acid is the primary acid in Jamaican rum traditionally made with muck. Other common acids (butyric etc) make up very small fractions comparatively. A distillery doing high ester rum needed to have vast quantities of it and it was usually made by fermenting a simple cane juice wash and throwing it over cane trash in an open pit.

It is certainly risky to use it in a fresh wash (which is true of any infection), but its a matter of weighing risk vs reward.
I didn't set out to make banana vinegar, but when I ended up with a very large quantity of it, I decided to put it to use. The muck will be used with low wines, but I may do a small fresh wash with some added after the yeast get a head start (just for comparison sake).

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Re: Where does banana flavor in Rum come from?

Post by butterpants » Sat Apr 07, 2018 4:57 pm

der wo wrote:I don't know, how tough the bacterias are. And if vinegar bacterias are more or less tough than for example lactic or butyric bacterias. All I can say is, that up to now I had no problems using the same fermenters for infected and uninfected batches. I clean with boiling water and a bit sodium hydroxide. Pouring it to the walls into the fermenter and brush it a bit. Either this cleaning procedure is safe enough or there is simply not enough time for the bacterias to take over my normal batches with normal fermentation durations.
Edit: I think, on any fruit I ferment are way more vinegar bacterias than in my fermenters after cleaning.

And as I wrote before, I doubt that a vinegar infection eats all the ethanol without pumping in air within 1 or 3 months, as long the wash has a pellicle.

Sugar or not sugar is off-topic. I don't want to debate it further. At least not in this thread.
Acetobater are generally gram negative and motile while Lactobacillus and Pediococcus are gram positive and non motile. Enteric stuff is all over the place (gram +/-, anaerobic/aerobic). This are just the common brewing contaminants.

I don't think that one is necessarily more difficult to kill than another, long as you follow best practices but their intrinsic differences can be vast.

Just gotta know how to clean and use a proper sanatizer. Boiling water works pretty darn good.

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Re: Where does banana flavor in Rum come from?

Post by der wo » Sun Apr 08, 2018 12:27 am

OtisT wrote:Test 1) One normal strip (no additives). I want to see if I get Banana after a strip from the same ferment (minus the dunder.) I am guessing not, but I may be surprised. (Save low wines for later.)
Test 2) Do a single run rum using fresh dunder/feints in my thumper. Because I lost banana after a second distillation, and assuming dunder is necessary for banana, I want to try with dunder/feints in my thumper so hopefully I will get the banana because I would be making that ester in the thumper (only one distillation of that ester.)
Test 3) Assuming tests 1 and 2 confirm that Dunder is a necessary ingredient to get banana, I will repeat test 2 again but using vinegar/feints as opposed to dunder/feints in the thumper.
Test 4) Same as three, but use Sulfuric acid rather than vinegar.
Test 2) on the one hand it's good that you have the feints (much higher alcohols) and the dunder (acids) mixed together, on the other hand the dunder is very near to the final product. I mean IMO the dunder needs more time/cleaning than the short way through the thumper. One distillation more or reflux. You want a single run with only one thumper and dunder in the thumper, two details less clean than a traditional Rum single run with two thumpers and high proof feints without dunder in the thumpers. Forsyths doesn't use dunder, but it's by far the highest banana level I ever tasted. Seems dunder is not needed for banana. Probably your dunder contains no vinegar. So I think you won't produce many banana esters with it. But perhaps with Test 3 and 4.
Test 3) This is a great experiment I think. Not easy to decide for a vinegar amount I fear. And like Test 2 I think it will be not clean enough.
Test 4) So you want to see, what esters you could get from the acids and alcohols of the feints alone? Ok, also a nice experiment. But why sulphuric acid here and not in the other experiments? Sulphuric acid doesn't work by acidification, but as a catalyst. It's not replacable by organic acids (vinegar or dunder). I would use it everywhere you want to promote esterification, doesn't matter what pH it has, or nowhere.

I will do 5 simple potstill stripping runs from 1 wash in summer. Soemthing like this:
1) normal stripping short after an infection has started.
2) same, but with sulphuric acid.
3-5) stripping runs after long fermentation with infection. Sulphuric acid depends on results from 1 and 2. Vinegar addition perhaps 4 and 5. Perhaps I add dunder from 1 and 2 to 3-5 partially.

Then 2 potstill middle runs with infected dunder and probably vinegar.

Then 1 spirit run, probably potstill too. Probably way higher abv in the boiler than recommended here.
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Re: Where does banana flavor in Rum come from?

Post by SaltyStaves » Sun Apr 08, 2018 12:51 am

der wo wrote:Not easy to decide for a vinegar amount I fear.
Yes, this has been a difficult question. I have been trying to assess it like this.
vinegar test.jpg
I bring the temperature up slowly, then pierce the foil and sample the aroma. If I detect vinegar, then I assume that a wash of similar proportions will also be a fail.
I'm sure there are much better ways, but I have to work with what I have.

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Re: Where does banana flavor in Rum come from?

Post by Saltbush Bill » Sun Apr 08, 2018 1:00 am

der wo wrote:Where does banana flavor in Rum come from?
I'm not sure if Ive ever tasted a rum that smells / tastes of bananas ?
If I have I sure haven't noticed it, maybe my sense of smell and taste is shot.
I"m not one of those folk who can describe the booze they drink as anything other than well made, badly made , To much heads, to much tails , good and bad are descriptions that spring to mind.
Terms such as fruit, oaky vanilla,caramel and full bodied are things I can understand maybe even buttery fits in to that lot of words.
But when we start wandering into areas of Bananas, plum, quinine, juniper, resin, apricot, mango,nuts, oak, biscuits, honey, nougat,chocolate and walnuts, Round mellow flavors of lush fresh fruit with hints of green apple and salty, honeyed nose that includes aromas of nutmeg, coriander, and cinnamon, well franky Im just a little bit &#@*# lost :wtf:
Yes folks I found all of those words describing Rums in about 2 minutes on google.
My point is that I pity the newbie who reads threads like this , they must wonder why the Rum they make does not taste of any of the above, or if it does only mildly.
Me ill just stick to my own method , my own recipe ..and make rum that tastes like Rum....not F#@* Banannas...and even then it wont taste much good until its been on the right oak for at least 6 months

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Re: Where does banana flavor in Rum come from?

Post by der wo » Sun Apr 08, 2018 1:09 am

What's in there, Salty?
Dunder, feints, wash, vinegar, sulphuric acid?

Yes. I will do also something like this. Before pouring vinegar into a wash, I would try it with a small sample, add a bit sulphuric acid and wait a day. And I will control the vinegar amount of a long duration ferment this way. For OtisT it's more difficult to decide, because he wants to use the vinegar in the thumper and the vapor from the main boiler will dilute the effect of it.
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Re: Where does banana flavor in Rum come from?

Post by SaltyStaves » Sun Apr 08, 2018 1:44 am

der wo wrote:What's in there, Salty?
Dunder, feints, wash, vinegar, sulphuric acid?
Low wines with developed muck (about 20% ratio with a pH of 6.2) with acetic infected wash that has a pH around 3.6. The mixture was around pH 4 all together and I could smell the vinegar in it when I first mixed them. Was barely detectable when vapourised.

Biggest flaw with that particular test was I only waited an hour to mix, then vapourise it. Next time, I'll give it 24-48 hours and maybe also aerate.

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Re: Where does banana flavor in Rum come from?

Post by Saltbush Bill » Sun Apr 08, 2018 1:58 am

der wo wrote:Dunder, feints, wash, vinegar, sulphuric acid?
Some of them even use hydrochloric acid, many use other things , I try to make my Rum using as few weird additives as possible.
Maybe I am just a caveman distiller
I still use the suck your finger method to find if my rum wash has finished. I do not and will not check PH...that is not an issue with any ferment I have ever had. I still run my still by eye , smell and taste.
I can and will use any still and not need a thermometer to do so.
Yummy is a good person to ask about acids and what effects they have on the flavors of rum, hes played the acid game a lot more than most have .

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Re: Where does banana flavor in Rum come from?

Post by der wo » Sun Apr 08, 2018 2:37 am

Hydrochloric acid? Because it's volatile, it's not a good idea I think.


Some behaviour here is childish. Some members feel attacked without a reason. Now either they say they have enough banana flavor, or they say they don't have and don't want to have it, or they say if you need to promote banana flavor something is wrong with your basic recipe.
It's like answering the HBB thread like "no, my Bourbon doesn't need speciality grains."
Again, this is not a "why all your Rum tastes boring" -thread. It's an experiment. Noone is writing condescending about your recipes without infections/acids here.
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Re: Where does banana flavor in Rum come from?

Post by butterpants » Sun Apr 08, 2018 11:25 am

Well said.

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