Ongoing Diacetyl ? off flavour
- Thread starter Bandit24
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Bandit24
Well-Known Member
If you’re talking about fermenter taps, every brew, fully pulled apart, soaked in Sodium Perc to clean and soaked in StarSan before use. Also used brand new taps on this latest split batch
Bandit24
Well-Known Member
I'm only using FWK's at this time / no AG.
That article is great thanks for linking. Very similar to what I'm going through, hopefully I can work out what the hell the problem is!!!
Hardly an issue when one is brewing FWC's
On the fridge fan, whatever works best for you, I have an old scientific fridge with a built in fan, have in the past used a 240V computer fan (if you go to Jaycar they have a plug and lead for theirs) know people who use a small desk fan... what ever works for you.
KE VO there are other reasons for using a fan other than just getting a stable temperature, try it and see.
Mark
labels
Well-Known Member
Yes, use a STEP DRILL to get clean, burr-free holes on plastic. Cheap and available from Bunnings.
goatchop41
Well-Known Member
If you want to really give the fridge a real nuke option, go for acidified bleach - it's way more potent than normal bleach.
You prepare the bleach as per instructions for dilution, but add an equal amount of an acid** (white vinegar was used in the journal article that I read). It kills much faster than normal bleach and I think it also kills a few more things too.
**DO NOT MIX THE ACID AND BLEACH DIRECTLY. That is how you make chlorine gas and possibly kill yourself. Do it in a well ventilated area, add the bleach to the water, mix well, then add the vinegar.
You prepare the bleach as per instructions for dilution, but add an equal amount of an acid** (white vinegar was used in the journal article that I read). It kills much faster than normal bleach and I think it also kills a few more things too.
**DO NOT MIX THE ACID AND BLEACH DIRECTLY. That is how you make chlorine gas and possibly kill yourself. Do it in a well ventilated area, add the bleach to the water, mix well, then add the vinegar.
Bandit24
Well-Known Member
Thanks
Bandit24
Well-Known Member
Bandit24
Well-Known Member
Sounds intense.
I’m looking to downsize my fridge anyway, might be time to look for something smaller
Bandit24
Well-Known Member
What does everyone think about the below that I posted earlier re: getting rid of equipment that may have been in contact with infected brews?
Couple of other questions regarding my potentially sullied equipment, how far do I need to go?
- I've got an unused FWK that's been sitting in the same shed for a couple of weeks, since the FWK cube is plastic like a fermenter, if the infection I'm getting that creates Diacetyl can get into plastic easily, is there a chance it could have somehow already infected the unopened FWK?
- I just bought an o2 kit, and the parts were stored once again in the same shed, in the same plastic tub that holds all of my other brewing equipment (a lot of which has been in contact with infected brews, which I will now be chucking), how thoroughly am I going to need to nuke the hose and wand? what about the regulator and stone?
- What about post-fermentation stuff like PET bottles, bottle tree?
Couple of other questions regarding my potentially sullied equipment, how far do I need to go?
- I've got an unused FWK that's been sitting in the same shed for a couple of weeks, since the FWK cube is plastic like a fermenter, if the infection I'm getting that creates Diacetyl can get into plastic easily, is there a chance it could have somehow already infected the unopened FWK?
- I just bought an o2 kit, and the parts were stored once again in the same shed, in the same plastic tub that holds all of my other brewing equipment (a lot of which has been in contact with infected brews, which I will now be chucking), how thoroughly am I going to need to nuke the hose and wand? what about the regulator and stone?
- What about post-fermentation stuff like PET bottles, bottle tree?
goatchop41
Well-Known Member
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
No one else has asked/mentioned:
- Are you spraying sanitiser into the tap and waiting 20 secs or so before opening?
- Have you tried with an airlock in the lid instead of cling film?
- 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.
GregTheBrewer
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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
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.
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.
Oh, and the taste of the beer after day 3 or 4 or 6 is no indication at all of what it will turn out like.
The beer changes dramatically over the first few weeks, and continues changing for a while after that as it conditions and ages.
The beer changes dramatically over the first few weeks, and continues changing for a while after that as it conditions and ages.
I've just got back into brewing, am trying out FWKs and have just kegged my second one today. The first one I did had a banana smell for the whole of the fermentation process and when I sampled it just before kegging, it had a slight banana taste. After two weeks in the fridge at 4 degrees there is no banana taste left and it's very nice so snails07 may have a very good point.
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.
MY BEER SMELLS OF BUTTER
Off Flavour: Diacetyl
Chemical Name: 2,3-butanedione
How to Identify: This one smells like butter, butter popcorn or butterscotch and can present with a slickness or creaminess on the tongue and in the mouth.
What it is: Referred to as brewing’s ‘original sin’, Diacetyl is present in most beers at some concentration and is a natural part of the brewing process. It can be a desirable flavour in small amounts in stouts and ales but is generally regarded as a flaw in most lagers.
How it is caused: Diacetyl is naturally produced by all yeast during fermentation and is then ‘reabsorbed’ by yeast cells. Any Diacetyl that is not reabsorbed may be a result of either high flocculating yeast, weak or mutated yeast, issues with oxygenating, low fermentation temperatures or short boils.
This brings me to a great piece of advice I was given (by a member of this community) as far as pitching your yeast goes when using FWKs. He suggested that you pour the first five litres into your fermenter and then add the yeast. If it's powdered then you need to give it time to spread across the surface of the wort to avoid clumping. If it's been rehydrated then it's not necessary. You then shake the crap out of it for at least 30 seconds before adding the rest of the wort and oxygenate in the usual way. This will speed up the fermentation process. It might be worth a try.
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.
MY BEER SMELLS OF BUTTER
Off Flavour: Diacetyl
Chemical Name: 2,3-butanedione
How to Identify: This one smells like butter, butter popcorn or butterscotch and can present with a slickness or creaminess on the tongue and in the mouth.
What it is: Referred to as brewing’s ‘original sin’, Diacetyl is present in most beers at some concentration and is a natural part of the brewing process. It can be a desirable flavour in small amounts in stouts and ales but is generally regarded as a flaw in most lagers.
How it is caused: Diacetyl is naturally produced by all yeast during fermentation and is then ‘reabsorbed’ by yeast cells. Any Diacetyl that is not reabsorbed may be a result of either high flocculating yeast, weak or mutated yeast, issues with oxygenating, low fermentation temperatures or short boils.
This brings me to a great piece of advice I was given (by a member of this community) as far as pitching your yeast goes when using FWKs. He suggested that you pour the first five litres into your fermenter and then add the yeast. If it's powdered then you need to give it time to spread across the surface of the wort to avoid clumping. If it's been rehydrated then it's not necessary. You then shake the crap out of it for at least 30 seconds before adding the rest of the wort and oxygenate in the usual way. This will speed up the fermentation process. It might be worth a try.
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.
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.
Danscraftbeer
Well-Known Member
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.
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