Ongoing Diacetyl ? off flavour

[Black Devil Dog]

Professional standards are if the seal is broken then discard.
Storing the mixed product:
Fresh is always best. The basic thing with storing starsan type sanitizer is your judgment. I will co2 purge a keg that is filled with phos sanitizer (like star san) push that sanitizer through very well cleaned kegs and then keep that ~18lt sanitizer on tap in a sanitary vessel. The basic is if its crystal clear and the pH is below 3.5 than its good. Mine actually reads at pH 2.5 - 3.0. If its got bits in it then when its fresh its ok, but if can see tiny contaminants in it, or its discolored or isnt crystal clear anymore than its shot. I have also let a bucket sit after that stage and it gets pretty funky. If its used too much it will definately spoil. Cross contaminations include chemicals as well like dont mix chems at all! Dont think that brewing cleaners can mix together. If it gets any beer in it its spoiled as it will get cloudy and slimey and get slimey strings growing through it. Other more scientific people here and elsewhere could talk on that but basic is cross contamination will spoil anything including sanitizer itself.

Re- Basic Rule. When in doubt, chuck it out. Phosphoric Acid Sanitizer is awesome. When used correctly! but Its not bulletproof.
San regular is a mix to make it frothy and sudsy.
I use the 96% pure Phos, less bubbles and it goes further.

Starsan doesn't have to be crystal clear to be effective.

If it's within the pH range it's fine.

 

[MHB]

Not so much the foam but the wetting agent properties of detergent, it helps the sanitising part work better by getting it into and under any soil.
Personally not my favorite sanitiser and I'm very suspicious of "no rinse" - well ones that leave any residue.
Mark

 

[mashmaniac]

Don't forget to bomb the ferment fridge. Having stripped so many over the years (yes mostly for the sake of this hobby) it is scary where mold and nasties can hide.

 

[Bandit24]

1) No, it should be fine. Bacteria can't get through plastic.

2) I would nuke all of the O2 gear (again, acidified bleach with multiple clean water rinses afterwards). If any of the parts for it are cheap and easy to replace, then you may as well just do that with those parts.

3) All cold side stuff will either need to be nuked (can just boil the ***** out of thick silicone hoses) or replaced, unless it is stainless, in which case it just needs a good clean with some caustic

Thanks

When you say "cold side stuff" is that referring to fermentation equipment only, or does that also include bottles and bottle tree?

 

[Bandit24]

No one else has asked/mentioned:

1. Are you spraying sanitiser into the tap and waiting 20 secs or so before opening?
2. Have you tried with an airlock in the lid instead of cling film?

Yes, usually the nasties fall down. But...

• After you fiddle, are you replacing the cling film? Nasties could be falling down on to it whilst you are inside your fermenter.
  
• Could your dog get to the tap? 100% sure that wort tastes quite good to a dog, any any nasties that live on your dog.
  
• If there is any wort/beer dripping from the tap, nasties could land onto that, and track into the tap.

Thanks for your post.

1. No, and thank you for bringing this up, because it definitely sounds like something that could be a problem. This will now be one of the first things I try.
2. Yes, but not recently. May be worth another try. All the advice I read on here was always "ditch the lid and go glad wrap". My main concern is air lock drawback during cold crash, what is your best way around this?

- I never open the glad wrap for any reason except dry hops, but no I don't replace the glad wrap after doing this.
- Dog definitely can't get to the tap
- I usually clean up any drips from the tap and then quick spray with starsan. However your point above about not spraying the tap itself could be a problem!

 

[Bandit24]

Bandit, a couple of thoughts. Did you oxygenate all the off brews? Could be the diffuser stone that is harbouring bugs...boil it in the kettle for 15 minutes and then only handle it with sterilised instruments.

The other thing I thought...just an off chance...you say it is butterscotch flavour? Popcorn flavour? You are using FWK's as I understand? Do you add any extra water to them? Could this be band-aid flavour if it is too unpleasant to drink? Get a bottle of Pilsner Urquell to taste what classic popcorn diacetyl tastes like and compare. If you are adding some water to your FWK's, it could be chlorine in the water that is reacting with your yeast and producing the off flavours...if so you need to de-chlorinate your water. I only ask this question cos you were not entirely sure what the off flavour was, and you seem to be paying a lot of attention to sanitation

The oxygen kit is only brand new and only used on the latest batch, so it's not the problem.

It's a sweet flavour and although I'm not 100% sure, it most closely matches the description for Diacetyl, and I have had a good look through the complete off flavours PDF that is floating around. I wouldn't say band-aid. There's nothing else in the PDF that I can match the flavour with.

Interesting about Pilsner Urquell, I didn't know they had a perceivable Diacetyl level, I will definitely try one again and make sure the flavour is the same.

I am interested in finding out the best way to use water when brewing with FWK's. I have tried multiple ways over the past, and particularly on these latest batches that all share the same Diacetyl flavour, I have used both supermarket packaged spring water, and boiled tap water on different batches and had the same problem, so I'm ruling out water related issues.

 

[Bandit24]

What does your fermentation temps and times look like?
I don't think you have an infection, I think it is just that your fermentations aren't quite as good as they could be. It sounds like you're pretty switched on with cleaning and sanitizing so I'd just about rule that out.

I've brewed in a garage for 6 or 7 years, dog coming in and out etc and have had no infections.

Your pitch rates sound okay, but for your next batch I'd
- make a starter to help kickstart the yeast
- once krausen shows first signs of dropping, slowly increase temps a few degrees over a day or 2. This will help clean up VDK's
- stop checking in and tasting samples. More chance for things to go wrong. Patience really is the way to go.
- let it sit in fermenter for min. 2 weeks and then *slowly* lower temp over 3-4 days down to 0-2c and hold there for a day or two. Total around 3 weeks.
- again, stop taking samples all the time

I've been through very simliar situation, I'd almost guarantee it is a fermentation issue. Not long enough, temps not right, somehow shocking the yeast.

Thanks for those notes, will use on my my next batch for sure, definitely more in depth that what I do now, which is basically pitch and ferment at optimum temp, raise maybe 1-2 degrees towards the end of fermentation, then cold crash as quickly as possible.

But in regards to solving my problem, I'd love this to be a fermentation/yeast issue, I really would, but I just feel like I've had far too little success in brewing over the past 12 months for it to be completely blamed on yeast health (16 batches, only 3-4 ok/but still average tasting batches, the rest have had something wrong). Although who knows, with more info like the above and everything that has been provided in this thread, I'll do some new batches and see what works.

In regards to yeast shock, I know on one of my recent 20L batches, I accidentally turned off my temp controller/fridge at the power point for about 2 hours, and lost about 2 degrees on the fermentation temp, down to about 16c, which then recovered to 18c in about 30 mins. This was at about day 4 in fermentation from memory. Does this sound like something that would produce Diacetyl? I know this isn't my answer for everything, but just wondering either way.

 

[Bandit24]

The one thing that stood out to me was the use of clingwrap on the top of the fermenter. I've done this and it's OK while you've got krausen but when the pressure drops and the clingwrap goes into a concave position it could lead to the introduction of some nasties. However, reading what you've done it doesn't seem like this is the issue. A website that I really like has this to say about diacetyl.

Thanks, what is your recommended method for the lid then? I know once pressure drops and during cold crashing, things can get sucked in, but still at odds to find the best method to seal up the fermenter during this time. Airlock can suck backwards, and perhaps glad wrap isn't a good enough seal. I've been looking for silicone bungs to place in the airlock hole, and cannot find them anywhere!

 

[Bandit24]

OK, about 45 years ago when I started brewing we had no closed fermenters available.
My first attempts amounting to maybe a dozen brews were all of poor quality with off flavours that I was then unable to ID.
My Dad laughed often, & helpfully suggested Black Label Scotch would be lower cost. Most of the really awful ones went down the sink.
I then married & we occupied a small flat with an outdoor potting shed.
Suddenly my brews were free of whatever the problem was, fermented in "Gladwrap" covered washing machine bowl situated in the potting shed (no dog).
Up to this time I had always used undiluted bleach to sterilise my gear, and plenty of it!
Water was from the same municipal supply, gear was unchanged, method unchanged.
So what was going on?
I never discovered the true nature of the problem.
Looking back as I often have done:
Use a filter for any tap-water used. I now use an under-bench carbon block filter 0.5 microns & draw water at about 3 litres per min MAX.
Consider brewing somewhere else, maybe at a friends place, even if just to prove a point.
At the very least don't use the dog shed!! It may not be part, or the whole, of the problem but you have to isolate the most obvious first.
Use lots of undiluted bleach & sterilise everything, include bench tops, all utensils, thermometers, hydrometer etc. Wash & scrub your hands & lower arms. Lay your gear down on dead dry freshly laundered tea towels (as a surgeon would his instruments).
CAUTION: undiluted bleach is dangerous, use eye protection always & dress in old clean clothes.
The bleach needs an exposure time of around 2 mins, it must be run through your fermenter tap & it must be allowed to cover the fermenter top & saturate the airlock.
Of course you will finally need to thoroughly rinse, (twice) all treated equipment; use only boiled water, water from the filter recommended or hot water from your domestic kitchen supply. Note that some hot water supplies operate at below the pasturisation temp of 70 deg C. You need to be sure any used hot water is sterile, so it must be capable of storing & delivering at this temp. Adjust your thermostat if necessary.
BTW things are clean when they smell dead clean - after sanitising & rinsing you can do the nose test.
Keep things covered where you can or where unavoidable exposure to air is likely.
Remember whatever organism is infecting your brews it's from: the water, the air, from you or your gear.
Keep trialing with K&K brews, and keep everything simple, don't follow red herring trails & you will find a solution even if not the exact source.
For the record: in the last 35 years I have had no infections in bottles, kegs, or in the fermenter.
Are my brews (from modified kits) great? Well they are OK but not fantastic.
That's the best I can offer, hope you sort this out soon.

Thanks for your help

- I am renting and cant add a water filter, what is your best method besides filtering - boiled and cooled tap water?

- Good to hear that someone has been through a similar environmental problem and after reading a few things in this thread, I definitely need to try a new environment.

- I'm not so keen on using heavy chemicals, would you say that a chemical like bleach can be replaced with something like StarSan? Or is the really no substitute for bleach?

- I'm not sure of my hot water temp, but I don't generally use hot water in the cleaning process. I would use warm water with Sodium Perc for cleaning, washed off with cold water, then StarSan. Do I need to introduce some hot water into this process?

Thanks for the insights, great to hear you've had no infections in 35 years, it gives me confidence that once I work out this issue it should be mostly smooth sailing!

 

[Bandit24]

1. Try a brew without dry hopping.

Thanks, I tried this, avoided dry hopping for two batches straight and still got the problem

 

[Bandit24]

Professional standards are if the seal is broken then discard.
Storing the mixed product:
Fresh is always best. The basic thing with storing starsan type sanitizer is your judgment. I will co2 purge a keg that is filled with phos sanitizer (like star san) push that sanitizer through very well cleaned kegs and then keep that ~18lt sanitizer on tap in a sanitary vessel. The basic is if its crystal clear and the pH is below 3.5 than its good. Mine actually reads at pH 2.5 - 3.0. If its got bits in it then when its fresh its ok, but if can see tiny contaminants in it, or its discolored or isnt crystal clear anymore than its shot. I have also let a bucket sit after that stage and it gets pretty funky. If its used too much it will definately spoil. Cross contaminations include chemicals as well like dont mix chems at all! Dont think that brewing cleaners can mix together. If it gets any beer in it its spoiled as it will get cloudy and slimey and get slimey strings growing through it. Other more scientific people here and elsewhere could talk on that but basic is cross contamination will spoil anything including sanitizer itself.

Re- Basic Rule. When in doubt, chuck it out. Phosphoric Acid Sanitizer is awesome. When used correctly! but Its not bulletproof.
San regular is a mix to make it frothy and sudsy.
I use the 96% pure Phos, less bubbles and it goes further.

Thanks, good info

 

[Bandit24]

Don't forget to bomb the ferment fridge. Having stripped so many over the years (yes mostly for the sake of this hobby) it is scary where mold and nasties can hide.

Thanks, this might have been an issue for me early on, but a few months ago I pulled apart the fridge as best I could, removed all glass shelves that I use, stripped off their plastic edges and cleaned, and also removed the door seal and cleaned. Also of course, just a full nuke of the inside of the fridge. And I've been giving the shelves/inside of the fridge a clean with sodium perc and starsan between each batch for the last 5 batches.

One thing I've always wondered, is can a fridge harbour contaminants in say the fan, or somewhere in the drip tray type area? My fridge has a small outlet hole at the bottom for condensation to drip out. I've checked out the rear of the fridge and can't see anywhere thats pooling water or anything like that, but still, I have wondered if there would be a particular type of fridge design that would be the best for fermenting.

 

[Bandit24]

OK, about 45 years ago when I started brewing we had no closed fermenters available.
My first attempts amounting to maybe a dozen brews were all of poor quality with off flavours that I was then unable to ID.
My Dad laughed often, & helpfully suggested Black Label Scotch would be lower cost. Most of the really awful ones went down the sink.
I then married & we occupied a small flat with an outdoor potting shed.
Suddenly my brews were free of whatever the problem was, fermented in "Gladwrap" covered washing machine bowl situated in the potting shed (no dog).
Up to this time I had always used undiluted bleach to sterilise my gear, and plenty of it!
Water was from the same municipal supply, gear was unchanged, method unchanged.
So what was going on?
I never discovered the true nature of the problem.
Looking back as I often have done:
Use a filter for any tap-water used. I now use an under-bench carbon block filter 0.5 microns & draw water at about 3 litres per min MAX.
Consider brewing somewhere else, maybe at a friends place, even if just to prove a point.
At the very least don't use the dog shed!! It may not be part, or the whole, of the problem but you have to isolate the most obvious first.
Use lots of undiluted bleach & sterilise everything, include bench tops, all utensils, thermometers, hydrometer etc. Wash & scrub your hands & lower arms. Lay your gear down on dead dry freshly laundered tea towels (as a surgeon would his instruments).
CAUTION: undiluted bleach is dangerous, use eye protection always & dress in old clean clothes.
The bleach needs an exposure time of around 2 mins, it must be run through your fermenter tap & it must be allowed to cover the fermenter top & saturate the airlock.
Of course you will finally need to thoroughly rinse, (twice) all treated equipment; use only boiled water, water from the filter recommended or hot water from your domestic kitchen supply. Note that some hot water supplies operate at below the pasturisation temp of 70 deg C. You need to be sure any used hot water is sterile, so it must be capable of storing & delivering at this temp. Adjust your thermostat if necessary.
BTW things are clean when they smell dead clean - after sanitising & rinsing you can do the nose test.
Keep things covered where you can or where unavoidable exposure to air is likely.
Remember whatever organism is infecting your brews it's from: the water, the air, from you or your gear.
Keep trialing with K&K brews, and keep everything simple, don't follow red herring trails & you will find a solution even if not the exact source.
For the record: in the last 35 years I have had no infections in bottles, kegs, or in the fermenter.
Are my brews (from modified kits) great? Well they are OK but not fantastic.
That's the best I can offer, hope you sort this out soon.

Is paper towel an acceptable substitute for freshly laundered tea towels for laying down gear after being sterilised? I have tried paper towel, but usually just sanitise my kitchen bench with a spray of StarSan. I don't launder tea towels that often to be honest. What does everyone else do for laying down their instruments?

 

[Bandit24]

Thanks to everyone for your comments.

Reading back through everything in the thread, it seems that basically any single part of my process/equipment could be the cause of the issue, so essentially it's looking like the best option is to completely start again, with new equipment, in a new environment, with new chemicals and new processes, if I want to be completely sure. Otherwise I face a possibly lengthy and costly exercise trying to figure out which part of the exisiting setup/process is causing the issue by going through it bit by bit.

Whatever I decide to do, I'll eventually report back with my findings. Cheers

 

[Bandit24]

Thanks. Can you run the fans 24/7 with no electrical fire danger?

Anyone got a tip with this one? Can I really run a ****** little fan inside the fridge safely for 24 hours a day?

I once had a battery operated camping fan burn out on me whilst sleeping in a car, nothing happened, but I'm nervous.

 

[MHB]

I wouldn't want a fan dying in my fridge either, bad for the beer!
I mostly use computer fans, buy a decent one and they tend to last for years, if you go on a mission to find the worst cheapest piece of crap money can buy and it croaks... well I guess you got what you payed for.
Air in fridges tends to be cool and dry, probably the perfect conditions for a fans life expectancy.
Mark

 

[Bandit24]

Thanks Mark, how does a computer fan get power? I have no idea how to do any wiring type stuff. I've been looking for a regular 240v plug in fan.
I'm happy to spend for something good, but everything that is small looks like this: https://www.target.com.au/p/velocity-desk-fan-tarvdf18/61496194

 

[MHB]

Last one I brought was from Jaycar and they sell a plug on lead, just a little thin figure 8 wire so it will go under the door seal. Also got a couple of wire guards and put one on each side, cant recall the exact price but it wasn't too bad.
The one you linked to looks like it would work, might be a bit on the big side, depending on your fridge.
Found it Jaycar Fan Power Lead $3.95 online, needs a plug fitted
Mark

Fark Jaycars product search sux - M

 

[Black Devil Dog]

Anyone got a tip with this one? Can I really run a ****** little fan inside the fridge safely for 24 hours a day?

I once had a battery operated camping fan burn out on me whilst sleeping in a car, nothing happened, but I'm nervous.

Jaycar have a few options.

I've got 3 of these Katabat fans, ($16.95 each) been running 2 of them in my fermenting fridges for about 3 years now. The other one I use in my Kegerator. I disconnected the **** fan that came with it and put one in its place.

The only other thing you'll need is a longer USB cable, as the one that comes with it is only about 500mm long. I bought a 1.5m.

 

[garage_life]

Thanks for your help

- I am renting and cant add a water filter, what is your best method besides filtering - boiled and cooled tap water?

- Good to hear that someone has been through a similar environmental problem and after reading a few things in this thread, I definitely need to try a new environment.

- I'm not so keen on using heavy chemicals, would you say that a chemical like bleach can be replaced with something like StarSan? Or is the really no substitute for bleach?

- I'm not sure of my hot water temp, but I don't generally use hot water in the cleaning process. I would use warm water with Sodium Perc for cleaning, washed off with cold water, then StarSan. Do I need to introduce some hot water into this process?

Thanks for the insights, great to hear you've had no infections in 35 years, it gives me confidence that once I work out this issue it should be mostly smooth sailing!

Check out caravan water filters on eBay, not the best but 2 are sub $20 and have the standard ouch to connect garden house coupling male side nipples inclided.
Get some food grade hose and new fittings at the big green shed and run them both inline and use a low flow rate, renters delight.
I drain them spray with sanitiser and keep them in a bag in the fridge when not in use. Don't have any water data but the taste is greatly improved over straight from the tap (which is still drinkable).
Best budget and ghetto option I've found dollars for doughnuts.