Yeild of Alcohol

[coop]

Oh, and Coop, if you don't mind some unasked for advice, I'd clean each fermenter and anything that touches your mash with caustic first, then acid. Disassemble anything that can be disassembled. Recycle all of your gaskets and replace them with new ones. I'd also take apart your pump and visually inspect for dead spots. Same goes for your air lines and filters if you aerate your mash. Use the best light source you can to inspect every nook and cranny. If you have a cold liquor tank or hot liquor tank, clean those tanks out, too. Check your water treatment system and filters. Visually inspect, and smell and taste everything. Make sure there is no evidence of soil on the stainless surfaces, since you can't sanitize if there's soil on those surfaces. Soil hides bacteria.

Then, I'd heat water in your still to just under boiling, and pump it to all the fermenters in your shop. Be careful to avoid vacuum and pressure in your tanks and pipes as the hot water moves in and eventually out. This is the most thorough way to sanitize your tanks outside of live steam, which may be less practical to accomplish. Make sure that you can read the temp of the water and you're looking good if the water is north of 180 F, but higher is better. Confirm with a thermometer that the water is hot enough at every point in the process, otherwise, it's pointless.

Double check your hose bands and fittings to ensure that they are secure as water that hot can pull hose barbs off in a hurry.

Drain the hot water, rinse thoroughly, and sanitize with the iodphor I spoke of.

Then check anything and everything that comes into contact with your grain. Grist case, scales, pails, mills. Disassemble where you can. Smell and taste everything in your plant. Again, use good lighting.

And last but not least, take a real close look at your yeast handling procedures. The easiest way for a lacto infection to take hold is for your culture yeast to be in a weakened state. Do everything you can to ensure your yeast is healthy, clean, and viable.

And on second thought, you might want to check with some of your area's vineyards, as they may have portable steam generators on hand that could steam sterilize everything for you in no time.

Hope this helps. Cheers

Good morning to you all. Todd, I used my mash kettle to heat water then flushed thorough all hoses,fermentation tanks everything. I do not have CIP systems on anything but the still. Open fermenters which clean easily. I purchased from 5 star the solution you recommended and cleaned everything, hose gaskets hoses, pumps both inside and out along with all fittings. Also used it on the floors of the fermentation room along with the walls and ceiling. The way we are handling the yeast is once we open the box all contents are put into baggies, sealed and stored in a refrigerator until needed. Started up again last Thursday and things seam to be ok for now. Thanks, Coop

[Denver Distiller]

The way we are handling the yeast is once we open the box all contents are put into baggies, sealed and stored in a refrigerator until needed. Started up again last Thursday and things seam to be ok for now. Thanks, Coop

Sounds great, coop. If you don't mind a wee bit more advice, I'd recycle all those gaskets.

Also, I think that perhaps we hit upon the major problem, if I'm reading your yeast handling procedures correctly. If you're breaking up a box of dry yeast, the instant O2 gets at the dried yeast, the viability and fermentative power of the yeast will begin to degrade. That's, imho, a very likely place where most of your troubles lie.... you're likely not pitching enough healthy yeast, and this is what gives your lactobacillus a chance to overwhelm the fermentation.

Perhaps you could pick up a seal-a-meal type machine that can vacuum seal those yeast bags. While not perfect, it's better than simply putting yeast in baggies that are filled with O2.

Or, alternatively, find a yeast that's packaged in smaller quantities that you open once, hydrate, and pitch. Or, alternatively, up your pitching rate when the bags have sat around for longer. You can do simple tests like calculating how many hours it takes for your yeast to get it to 5 plato. If fermentations start to take more time to get to 5 (even a 5% lengthening in fermentation time), you know you have a problem.

For your surfaces like floors, etc. I'd recommend looking into a different sanitizer, perhaps a foaming sanitizer that's more effective in that environment. Five Star can help you with that.

Recall it's hard to diagnose a problem sitting here at a computer, but I'm really trying my best to help.

Happy Distilling

[Chris Martin]

Todd -- man, this is good info. Thanks for your insights -- and thanks to everyone else... this is valuable education!!

[nick jones]

I just got through reading this very interesting topic, and I thought I'd throw in some questions and comments as well.

First, the questions, Coop:

1 - Do you in fact have refractometer AND hydrometer data from when you were having a brix drop from 15 to 5 brix but not having ETOH yield problems? If so, what are they?

2 - Do you in fact have refractometer AND hydrometer data from when your ETOH yield dropped? If so, what are they?

3 - Were there any changes in your mashing technique?

4 - Do your enzymes come from the grain naturally or do you add enzymes?

As might be clear from my questions, I'm wondering if you are getting inadequate starch conversion. I'd agree that a leaky still is also a possible culprit, as has been mentioned previously. I don't think that LAB could possibly be the sole cause the drop in yield that you are talking about (I've distilled spontaneously fermented beer riddled with brett, lacto, pedio, and god knows what else before, and the reduction in ETOH yield was nowhere near 50%), but it never hurts to give your stuff a thorough cleaning anyway. If any microbe is going to be chewing through massive quantities of ETOH, acetobacter would be my first guess. Try to keep your fermentations as anaerobic as possible to mitigate any acetobacter problems, but 50% is still a little high even there, if you ask me. You'd be making malt vineger.

Keep in mind that refractometers and hydrometers are reading VERY different things: refractometers read refraction and hydrometers read density (speaking generally). Neither instrument reads sugar content, though they are quite convenient for reading sugar content if used correctly.

Both hydrometers and refractometers are very accurate at reading a mixture of sugar and water. When the solution becomes a solution of sugar, water, and alcohol, things change drastically.

In the case of the hydrometer, you will be getting a brix reading that assumes a mixture of sugar and water. Adding the alcohol to the mix will cause you to have an erroneous reading that is too LOW, since alcohol is less dense than water, and the hydrometer is reading the density of solution.

In the case of the refractometer, you will also be getting a brix reading that assumes a mixture of sugar and water. Adding the alcohol to the mix will cause you to have an erroneous reading that is too HIGH, since alcohol increases the refractive index of the solution, and refraction is what the refractometer is reading. (check out http://moundtop.com/fermentation/RBRIX-ATC-Fermentation-Tables.pdf for a quick explanation)

So, from a refractometer's stand point, you could read a 15-5 "brix drop" and in one case have the 5 "brix" remaining be due to a high alcohol content, while in another case the 5 "brix" remaining could be due to a low alcohol content and high sugar content. If you also happened to take hydrometer readings at the same time as these refractometer readings, in the case of high alcohol content you would have your refractometer reading 5 and your hydrometer reading something like 1 or 0 (or even negative), while in the case of low alcohol and high sugar content, you would have your refractometer reading 5 and your hydrometer also reading 5 or slightly less.

Possible causes of high residual sugar would be mash temperatures that are too high, mash pH that is too high, insufficient gelatenization of starches, duff yeast, and others. Commercial distiller's enzymes take care of most of these issues for you if used correctly, so I'm wondering if you're adding enzymes or not? If you are adding enzymes, I'd suspect yeast problems if you're still getting under-attenuation. An iodine-based starch test should tell you if you have starch remaining in your mash or not, but remember that starch isn't the only unfermantable sugar.

As far as attenuation goes, accurate hydrometer readings will give you a better picture than refractometer readings, though both together would be quite telling. As was mentioned earlier, the only sure way to get the true picture of the alcohol content of a solution of three or more different things is to reduce it to a mixture of two (i.e. a solution of ETOH and H2O through distillation), then measure it with a hydrometer or refractometer (or a DMA 500 if you're one of those lucky bastards that can afford one).

More food for thought...

Nick

[PeteB]

Excellent information about refractometers in your post Nick.

Anyone using a refractometer should thoroughly read the link in your post.

I was making the same point in my post #37 but you have gone on to explain it much better.

I often see posts and speak with people who are concerned that Brix does not go to zero, they usually assume that fermentation is not complete.

[Rich Morgan]

LAB bet my cat on it.

[Denver Distiller]

You work in a large plant, Mr. Morgan. Have you ever lost yield to lactobacillus?

[JohnD]

I think it's also important to note that a refractometer measures glucose, maltose, maltotriose, and other maltodextrins (glucose is a single sugar molecule, maltose is two glucose linked together, maltotriose = 3). I've tested these devices with maltodextrin powder in water and gotten readings with only maltopentaose (5 linked) present meaning they're pretty indiscriminate.

Most distillers yeast can metabolize all of these effectively but if you've got a serious contamination, the bacteria will go like gunbusters on the maltodextrins while the yeast metabolizes pure glucose at the beginning of the fermentation. In the course of a normal ferment the yeast will switch over to maltodextrins once the glucose is depleted. If there is a significant contamination, there will be a huge microbial presence (having thrived on maltodextrins during the beginning of the ferment) and the yeast will be outcompeted while it's trying to activate the metabolic sequences it needs to metabolize these other sugars.

Starch conversion has been mentioned but if refractometry is your primary measure of conversion during mashing you may not be getting good saccharification, while still reading negative for the iodine starch test. I'm not sure how this works with hydrometers and whether they discriminate better between dextrins, but I doubt it.

So yet another potential culprit to add to the ever growing list here is inadequate saccharification (conversion of starch and dextrins to glucose). This is the one circumstance where I could see an LAB actually causing a drop as high as 50% in yield: serious contamination combined with inadequate saccharification.

[Rich Morgan]

You work in a large plant, Mr. Morgan. Have you ever lost yield to lactobacillus?

Have worked in several large facilities, but my current operation is relativity modest. When I was working in Malaysia (primarily due to the ambient temperature) we used to get LAB infections, better hygiene and larger inoculations kept it all in place.

rich..

[Rich Morgan]

You work in a large plant, Mr. Morgan. Have you ever lost yield to lactobacillus?

Have worked in several large facilities, but my current operation is relativity modest. When I was working in Malaysia (primarily due to the ambient temperature) we used to get LAB infections, better hygiene and larger inoculations kept it all in place.

rich..

[PeteB]

Hi Coop, how did you determine that you had a Lactobacillus infection?

I am asking because I am concerned I may have a similar problem.

[Brian]

here is an old article on control of infections.

Reese H. Vaughn, Don Truax, Don Little, and E. M. Mrak

The Use of Sanitation to Control Yeast,Bacteria and Molds a Seminar

Am. J. Enol. Vitic., Jul 1950; 1: 129 - 137.

Other cursory research leads to the notice that LAB will consume nutrients, i.e. tartaric acid, directly as well as set into place conditions enabling stuck fermentations.

The wine world has been in a tizzy about using malolactic fermentation to control the negative aspects of malic acid in wines for quite some time....literally hundreds of papers have been written....so direct losses from LAB consuming ethanol directly may be more limited than what COOP experienced but he may have set in motion a wide range of parameters that contributed to his loses.

We had a runaway infection last week that we presume was from contaminated rye and the dust associated from grinding this rye....a couple blasts of "sani-date" in the armpits seems to have helped.

[Denver Distiller]

Have worked in several large facilities, but my current operation is relativity modest. When I was working in Malaysia (primarily due to the ambient temperature) we used to get LAB infections, better hygiene and larger inoculations kept it all in place.

rich..

You're being modest, Mr. Morgan. Hunter is quite a large operation.

I still believe that the lacto. is a symptom rather than the underlying issue. 1/2 a drop in yield is an awful lot to ask of bacteria, and bacteria alone, when such a large portion of a mash is boiled, and we're talking about a fermentation that takes place in well under a week. I'm sure coop will share more as time allows.

[coop]

Hi Coop, how did you determine that you had a Lactobacillus infection?

I am asking because I am concerned I may have a similar problem.

I will be getting back to you all, I've just been real busy. Coop

[Jake Norris]

I will be getting back to you all, I've just been real busy. Coop

Having read everyone's contribution, I have to agree that infection alone should not account for such considerable loss of alcohol. I would look for errors in process as well. I am a big fan of the old "idiot check". Does the drain valve on your still leak? If you can, borrow a FLUER look at your still and see if you have unexplained thermal venting that would indicate a leak? Is your condensed product cool enough that it is not volatilizing and evaporating in to the air? Are your helpers somehow losing product? Retrain and reconfirm SOPs. I call it an idiot check, but sometimes we cant see the forest for the trees. I was noticing a loss in production and found the culprit to be a leaky butterfly valve at the bottom of my spirit still. Because of a worn out $20 gasket, I was literally letting my hard work and profits leak down the drain. Another time, I watched an assistant let the alcohol between gaskets fall on the floor when disconnecting hoses. I had to explain to him that those 'pennies' will make or break a small distillery and he is to use a drip pan. Try to look at your process with someone-elses eyes and look for the things that you are too familiar to see with your own eyes. Maybe ask a local friend in the industry to come and look?

I dealt with a nasty infection a while ago and to finally beat it we had to go nuclear. I pumped live steam through every single vessel and piece of equipment that has contact with any part the process. I replaced each and every gasket, took apart my heat exchange and sterilized all parts replaced any serviceable parts. It was expensive- and a pain, but we finally beat the infection, and in the end that is cheaper than compromising your product. I am also a fan of regular sanitation as part of your process, all of our fermentation and holding equipment undergoes brewery style caustic, acid, and sani CIP on a regular basis.

You are on the right track, just apply the scientific process and eliminate one factor at a time. I think in the end you will find that it was a number of small culprits conspiring to create one big problem. Do a few plates to see what you are dealing with, that should speed things up.

Good luck!

[flip2spin23]

After reading thru this thread a few times.Would the bacterial infection not also cause a oil to from? There is a ton of great info here. I am kinda curious to know more about the different sterilizing methods and products that some of you guys are using.

[lightcahill]

you are probably seeing corn oil is it red? This is not from lab. Just good whiskey making procedure.

[Rich Morgan]

Would "Fermaid-K from White Labs be what you are talking about?

Best source of nitrogen for fermentation is Food Grade Di-Ammonium Phosphate or DAP. Cheap and readily available. Anything up to 3g/L is typical.

[Jason Parker]

Hi Coop,

I've been checking back on this thread every month to see if you ever determined, conclusively, the cause of your alcohol yeild drop. I'm still doubting LAB, and holding onto my contention that a drop like you experienced could only be caused by a vapor leak.

So, what was it? (To quote the National Enquirer) "Inquiring minds want to know!"

Thanks,

Jason

[nick jones]

This thread started out so well...

I second Jason's appeal to you coop, but I would even be content to hear that you have found nothing conclusive yet.

What's the status?

Nick

[coop]

My whole hardly apologies for the delay in not responding much sooner. I finely contacted the local Farm Administration to check out the quality of the last batch of corn I got in. Per bushel weight was moderately low which in turn made available starches LOW. We brought in a different strain of corn and thing got back to normal. But I now have much better sterilization program which I know also helped. Again, sorry for not being a good member of the forum. Coop

[Denver Distiller]

Thank you for sharing this with us.

[Jason Parker]

I never gave up on you, Coop! Thanks for posting.

Jason