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devo666

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Hi This is my first post!!
I used to be a winemaker for 25 years, so know a bit about yeast.
Yeast need nitrogen to grow and reproduce.
We used to add DAP (Diammonium phosphate) as a nitrogen source for the yeast which is a good clean source of nitrogen.
I also if that is not available the yeast break down amino acids to obtain nitrogen many of which contain sulfur.
The sulfur then combines with Hydrogen to produce rotten egg gas (H2S).
If that is not removed it will get converted to various mercaptans which are much more stable and hard to remove and much more pungent.
Hi ferment temps will see the H2S convert to mercaptans very rapidly.
The Mercaptans are typically burnt rubber, cooked cabbage, garlic odors etc.
They can be removed by fining with copper-sulfate, but that needs to be done after running fining trials to determine exactly how much to use and prevention is better than cure
The best thing is to add DAP and ferment at cooler temps because when yeast races it uses up a lot of nitrogen very quickly then starts chewing on amino acids and bingo your ferment stinks.
Hope this helps.
Dave
 

GregTheBrewer

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My neighbour uses tank water as well and never bothers with minerals unless I give him some 😉
His beers turn out good too.
We are both all grain, but I can't see why that would make a huge difference compared to the kits you are using.
Cheers
Westy, the one big difference between all grain and extract (well, there are lots actually!) is that you boil the wort. This makes sure that any rogue bacteria or yeasts are killed. With extract brewing, unless you also boil the water or your filtration system is spotlessly clean, you are open to contamination. If Livo is using tanked rainwater, then it is not chlorophenols...that really only leaves yeast autolysis or contamination as the possible causes.
 

MHB

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Wine making and brewing have a few differences, the yeasts we use likewise.

One important part of mashing if to produce FAN (Free Amino Nitrogen) by the action of proteases (there are many) on protein, amino acids and peptides. A well designed mash will produce plenty of FAN and a timely boil will get rid of most of the higher molecular weight proteins that can cause other problems.
Ale yeasts and Lager yeast manage Sulphur quite differently, Lagers can throw H2S, its rare in Ales, in part from the higher kilning temperatures ale malt is subjected to which reduces SMM to DMS that is volatilised off in the kiln...
In brewing we generally use a complex Yeast Food, which contains some DAP and a lot of lased yeast with vitamins and minerals. If you feel the need to supplement a wort, this is a better option than DAP in brewing.
Mark
 

livo

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I remember making kit Apple Cider that used to be supplied with a packet of yeast nutrient as well as the yeast. I hadn't considered that my rainwater may lack nitrogen. I'll investigate this but I don't believe it is an issue. I have been able to make plenty of good beer from rainwater before today. It would contain NOM (natural organic matter) from decaying leaves in gutters. A yeast nutrient might not hurt.

I have bottled my first temperature controlled brew on day 8 and it tasted OK from the hydrometer tube. I've immediately put another batch in so we'll soon see how I'm going.
 
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Probably can’t give you a single "Right" answer, that isn’t how yeast works.
With the right amount of yeast you will get primary fermentation over in 5 days in most beers, maybe a couple of days longer for a cold brewed Lager or a very strong beer. At work we can knock a 10% Ale over in 7 days, 10 days to kegging, and routinely make 6-7% beers in 7 days from pitching yeast to kegging.
Greg above mentioned using a pitch rate calculator to work out how much yeast to use, that or learning the calculations is a very good idea.
The two main factors that affect yeast autolysis are Temperature and Time. Underpitching means the yeast is working harder and doing more reproducing, both will encourage autolysis.
If you are culturing yeast there are factors that will affect the chances of autolysis (doesn’t sound like that going to be an issue for you yet).
If you want to avoid autolysis, pitch the right amount of healthy yeast at the right temperature.
Never leave the beer on the yeast cake for more than 14 Days (EVER!)
Brew at the right temperature.
If you are making Lager, plan on racking the beer to another fermenter so you aren’t on the yeast too long.
As a kit brewer you aren’t making your wort so you don’t have to worry so much about nutrients, if you start mashing that can be another thing to look at later.

Mark

And then there's yeast from bottle carbonation sitting at the bottom of bottles. The amount is small but not negligible. To me it's one reason to keep the beer cold after carbonation.

I once bought Coopers pale ale in a US Midwest liquor store. The yeast was there at the botton. The manager said it had sat on a shelf (at @ 22 C) for the better part of a year. How long it had been in ships, trucks and warehouses, who knows? On opening it had carbonation. Two tasters tried it. No burnt rubber or other really bad offtaste. Not a lot of flavour of any kind other that what I'd call bitter, cold vegetable broth. Strange.
 

MHB

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Just a FYI, Coopers bottles have a "Best After" date on them, that is two weeks after packaging, they hold the beer in the warehouse for that long before its released (memories of brewery tours past...)
Autalysis can present in many ways, from fault guide posted above: -

1641199440187.png

Interesting that you chose the term Broth, probably a sign that the beer was well past its best.
Mark
 
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Just a FYI, Coopers bottles have a "Best After" date on them, that is two weeks after packaging, they hold the beer in the warehouse for that long before its released (memories of brewery tours past...)
Autalysis can present in many ways, from fault guide posted above: -

Interesting that you chose the term Broth, probably a sign that the beer was well past its best.
Mark

I'm at a loss how Coopers ended up there,. It happened in the early noughties. Although it would have come from an Illinois distributor, I never saw Coopers anywhere else in the States. By that time the 24 oz. gold cans of KB, once beloved for frat parties, were a memory, and Americans were hearing from Paul Hogan that "Fosters is Australian for beer."
 

livo

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Update.
Despite both "hot" brews sitting next to each other on the bench for the same duration of fermentation, on day 12 in the bottle the Lager has developed the same burned rubber autolysis flavour as the previous dumped brews while the Canadian Blonde has not. This off flavour was not present last week when sampled green. Both kits use the same yeast and sanitation and preparation were identical. Now I'm scratching my head a little.

Lager in PET, Canadian Blonde in glass. Hmm. Maybe, but why?

The Canadian Blonde is actually really nice on day 13 in the bottle whereas the Lager is looking like another drain cleaner.

PS: Just been out and bought a few cans including 2 Brigalow. These are supplied with 5 g yeast packs and the instructions say the yeast is suitable for 16 - 35'C "to suite Australian conditions". Best pitched at 30'C and fermented at 27'C.
 
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livo

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As in Jesus and Mary, knew each other? The only Canadians I know lived in -30 and never saw each other naked until they were married, and then not too frequently after that. Completely understandable but it would be a shock for many of them. They came out here for 12 months and he was surprised she was so skinny. Hard to tell with all that clothing on.
 

GregTheBrewer

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Livo, just a little wary of you using the term "burned rubber autolysis flavour" when describing the lager. We still don't know that it is yeast autolysis causing it. Given that the two brews were done in virtually identical conditions I would be now suspicious of an infection. Replace your soft items (rubber seals etc) and then sanitise the hard items within an inch of their lives. I usually sanitise my fermenter the night before with Starsan and let it sit all night. Try boiling your source water and letting it cool before use. I know you said it's filtered, but....one of the problems with infections is that they can be inconsistent. If you happen to get a batch of yeast that quickly becomes dominant and crowds out any other micro-organisms, you are OK, but the opposite can happen too. I once had a troublesome infection problem that I tracked down to a bit of crap in the fermenter tap!
 

Westheimer

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Westy, the one big difference between all grain and extract (well, there are lots actually!) is that you boil the wort. This makes sure that any rogue bacteria or yeasts are killed. With extract brewing, unless you also boil the water or your filtration system is spotlessly clean, you are open to contamination. If Livo is using tanked rainwater, then it is not chlorophenols...that really only leaves yeast autolysis or contamination as the possible causes.

Thanks Greg
You are right of course.
I was assuming that kit wort is getting boiled as well.
Any reason why you wouldn't boil it?
Would certainly make a lot of sense to me. Would kill any bugs and one would only have to worry about the thereafter 😉
 

livo

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Thanks Greg. I agree and I've amended the description. The fermenters were fitted with brand new taps and airlock grommets right before the first 2 warm batches. I wasn't happy with the seals provided by the old airlock grommets (10 years old) and one of the taps leaked. The old original stuff produced 3 good batches in cooler temperatures directly before these replacements and the 2 tipped brews. The old taps looked grubby internally and one leaked but three batches of beer were good. Brand new taps and seals were sanitized and I've got the problem.

I am still betting on autolysis, heat / temperature and/ or possibly time in FV, but I've been wrong with many things before today. The FVs are press fit lid bucket style. No O-rings and everything was sanitized and exposed to the sun for a few hours.

Water is a possibility but I'm doubtful and the batch(es) I've done in temperature controlled environment (another in now) should shed some light on that. Of course I will go and boil a couple of big pots of water and cube it to test that avenue just in case.

The helpful advice is very much appreciated.

Westheimer, I would argue that the whole point of extract concentrate kit beer is to avoid the hassle of boiling. It isn't a process required in the instructions and so I would imagine that the majority of kits brewed around the globe are not boiled. This may be different for enhanced kit brewing, but wouldn't additional boiling of just the concentrate change the hop profiles, etc of the extract already boiled and concentrated. That part of the brew process is already done (or replicated anyway). I doubt any kit supplier would be in business long selling contaminated concentrates.

I find it really surprising that the Lager appears to be more affected than the other beers. In the first instance, of the 2 dumped warm batches, the lager was worse and now in the second instance, with the really hot ones, the lager has gone off in the bottle while the CB is still good to drink. All new cans, in date and consistent processes involved.

I am going to go out and buy a bottle of brewing sanitiser, Starsan or whatever brand I can get from my local HBS. Over the years I have only ever used SMBS and diluted bleach water with adjusted pH, (white vinegar). I need to eliminate all possibilities obviously. I still have pink powder but I've done all my recent sanitizing in bleach, not to a concentration that would cause it's own problems. Actually, I'll probably need to order it online. As of yesterday I am a Close Family Contact so I'm not allowed to go to the shops for 7 days at least. More if I develop symptoms and test +ve. Doh!!!!!
 

GregTheBrewer

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Thanks Greg
You are right of course.
I was assuming that kit wort is getting boiled as well.
Any reason why you wouldn't boil it?
Would certainly make a lot of sense to me. Would kill any bugs and one would only have to worry about the thereafter 😉
No, I was only referring to boiling the water that you add to the kit to make it up to volume. The concentrated wort in the tin has already been boiled and therefore is sterile, and does not need any more boiling.
 

GregTheBrewer

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Thanks Greg. I agree and I've amended the description. The fermenters were fitted with brand new taps and airlock grommets right before the first 2 warm batches. I wasn't happy with the seals provided by the old airlock grommets (10 years old) and one of the taps leaked. The old original stuff produced 3 good batches in cooler temperatures directly before these replacements and the 2 tipped brews. The old taps looked grubby internally and one leaked but three batches of beer were good. Brand new taps and seals were sanitized and I've got the problem.

I am still betting on autolysis, heat / temperature and/ or possibly time in FV, but I've been wrong with many things before today. The FVs are press fit lid bucket style. No O-rings and everything was sanitized and exposed to the sun for a few hours.

Water is a possibility but I'm doubtful and the batch(es) I've done in temperature controlled environment (another in now) should shed some light on that. Of course I will go and boil a couple of big pots of water and cube it to test that avenue just in case.

The helpful advice is very much appreciated.

Westheimer, I would argue that the whole point of extract concentrate kit beer is to avoid the hassle of boiling. It isn't a process required in the instructions and so I would imagine that the majority of kits brewed around the globe are not boiled. This may be different for enhanced kit brewing, but wouldn't additional boiling of just the concentrate change the hop profiles, etc of the extract already boiled and concentrated. That part of the brew process is already done (or replicated anyway). I doubt any kit supplier would be in business long selling contaminated concentrates.

I find it really surprising that the Lager appears to be more affected than the other beers. In the first instance, of the 2 dumped warm batches, the lager was worse and now in the second instance, with the really hot ones, the lager has gone off in the bottle while the CB is still good to drink. All new cans, in date and consistent processes involved.

I am going to go out and buy a bottle of brewing sanitiser, Starsan or whatever brand I can get from my local HBS. Over the years I have only ever used SMBS and diluted bleach water with adjusted pH, (white vinegar). I need to eliminate all possibilities obviously. I still have pink powder but I've done all my recent sanitizing in bleach, not to a concentration that would cause it's own problems. Actually, I'll probably need to order it online. As of yesterday I am a Close Family Contact so I'm not allowed to go to the shops for 7 days at least. More if I develop symptoms and test +ve. Doh!!!!!
Hi Livo. There's a lot to tackle here! Let's start with the easy bit first. I already replied to Westheimer, and you are absolutely correct: you do NOT need to boil extract when you are doing an extract brew: the manufacturer has already done that for you. I was, as you correctly assumed, referring to boiling the water you ADD to the extract beforehand to know it's sterile.

You have done well replacing the taps and grommets: good for you. That's one possibility minimised. The FV's should be fine as long as they are well sanitised. Now, with your bleach sanitising routine, do you make sure that you have thoroughly rinsed out everything that will come into contact with the beer after you have done it? Even dilute bleach can leave enough residual chlorine (especially in plastic FV's) to react with the brew unless it is scrupulously rinsed out. The resultant chlorophenols can give a seriously off flavour, and it's one of those things than can vary if the residual amount varies.
Starsan (or equivalent from the LHBS) is phenomenal stuff, because it works very well and it is no rinse: you don't even have to worry about getting rid of the foam that's left in your FV after you use it (helps feed the yeasties!). I would be willing to make a bet that once you have started using Starsan and stopped using bleach, and combined that with temperature control, your problems will stop. Look forward to hearing how you get on.

Why is the lager more affected? Because lager yeast is far less tolerant of higher temps than ale yeast, and is much more likely to produce off flavours when stressed.

Oh, and I feel your pain about isolating: I tested positive to the bloody thing on Tuesday, and am waiting for confirmation via PCR. Bloody shit virus!
 

livo

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Greg, yes I have rinsed after sanitizing with boiled, but not hot, water. You obviously don't believe the theory of bleach, in low concentration with pH adjusted, being a good no-rinse sanitizer. I'm sceptical but I don't see the point in sanitizing and then rinsing in unsanitary water, hence the pre-boiled water for rinsing and the sun treatment.

(provided it's acidified slightly. 0.1% bleach and 0.1% white vinegar is an effective no rinse sanitizer.) and this,
Bleach: cheapest most effective no rinse sanitiser homebrew

However, no-rinse doesn't mean flavour free and you have to get the bleach out, as you correctly say.

After my sanitizing, and rinsing, I always put my gear out in the sun for a few hours with FVs upside down and bottles on the drainer tree. My dad always told me, and still does, that UV from the sun is the best sanitizer. I've had issues with bleach before so I'm pretty careful, but I will be getting into Starsan / Stellarsan or whatever it is I can get my hands on. It was becoming a thing when I last brewed but I never got around to getting any and haven't yet. It's coming before my next batch. I've never liked using pink powder either.

What is the product that people get from Aldi that they claim to be the same thing as Starsan?

About the lager being more affected, it isn't lager. It says Lager on the can but it is supplied with Coopers Ale Yeast. This is the same yeast as the other Coopers beers I've made except Mexican Cerveza. That's what confuses me.
 

livo

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Just the bog standard cans of Coopers Lager from their original range.
Coopers Lager Concentrate Extract Kit.
Available everywhere and according to the information I've seen, it is supplied with their bog standard Coopers Ale yeast. A bit stupid really when they supply Mexican Cerveza with the blended yeast of Ale and Lager.

I've ordered some 34/70, Diamond and US-05 so I'm hoping that with temperature controlled fermentation I might get a better result. I'm in the process of building an insulated "brewery" in my shed. I may need to wait till cooler months to actually get some appropriate temperatures for conditioning / lagering.
 

GregTheBrewer

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Yes, you're right. The original series kits all use the proprietary Cooper's Ale yeast. I just wondered if you had done one of the others that did have an actual Lager yeast. I agree with your comments about what they supply!

What neck of the woods are you in? Trust me, temperature control makes a WORLD of difference. Even here in Melbourne with its crazy weather I can happily do lagers in summer (if I want to...though I usually do them in the cooler months). What strategy are you using to chill your wort down before pitching the yeast? Also, do you rehydrate the yeast? Opinions on this deal greatly...some don't bother, others do. I started doing it about 50 brews ago (when I'm not using liquid yeast) and I have consistently got excellent results, so I'm a believer. In fact, I suggested rehydrating dry yeast to my wife for baking, and SHE has found a big difference in the bread as well! Crazy, huh!
 

livo

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Greg, I've ordered 2 different Lager Yeasts and US-05. I now have temperature controlled fermentation. I'm Central Coast NSW. Up to now I have not bothered with doing anything with the supplied kit yeast other than dumping it in, within the recommended temperature range. This is after all how these kits are marketed and the instructions imply that this is all that is required. Of course we know that it can be improved upon but hey, it's home brew after all. A mug's game at getting cheap beer at the moment. I intend to do some more once I get going, and lagering will certainly be easier in the winter months. I've tried to do a lot really quickly in a few weeks after a 10 year break. I used to do whole grain and I've done other whole grain mashing (with enzymes).

I'm a baker as well and I'm well educated about yeast, proving, proofing, hydrating etc etc. Biga, poolish, sourdough. I've captured wild yeast for bread and done natural vinegaration. If the instant yeast is in date, I just use it as it's intended and I've not had any issues. Bread, pizza and naan. I have my own Tandoor and I cook restaurant style curry. If the yeast is suspect you get zippo.

I have just found some of my old Coopers yeast packets that are 9 - 10 years out of date. I won't attempt to use them but I will drop them in some liquid with sugars just to see if they are alive. 10 years out of the fridge and exposed to some serious heat in the shed. Should be interesting.
 

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