All grain brews sour/yuck

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Michaelmacd

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Hi all. First post.

I've been brewing for years on and off. Kits and extract mostly and recently done about 5 all grain I would say using brew in a bag.

I couldn't guess how many kits I've done. Kits with hops added, and extract brews. The vast majority have came out very drinkable across pale ales, faux lagers and stouts.

Since starting all grain I've never had one that wasn't sour. Nothing's changed in regards to sanitation, fermentation, yeasts, hops, bottling, water and storage so I can't see why every one has a distinct sour flavour.

I've recently changed all fermentation buckets, bottles, tubing, bottling wand, airlocks. Anything I could think off and still that sour taste :(

I have even tried an all extract brew in the middle of it all which turned out brilliant!

Basicly with the all grain brews were brew in a bag and have been either marris otter pale malt, or UK lager malt. Mashing at 66'c for 1 hour and Never sparged it. Did a full volume boil for 60 mins. Fermented for 2 weeks and then batch primed in a separate bottling bucket and bottled in glass.

Everything I use has always been cleaned thoroughly and then used star san to sanitize.

I'm wondering if all starch has maybe not been broken down during my mash and giving the sour flavour. Next step is to invest in some iodine and if that doesn't work then all grain is getting binned. Not sure if this could give a sour taste but it's the only thing that I think can be different from my extract brews?

Sorry for such a long waffling post. Thought I better ask for help as I've just dumped roughly 80 bottles of beer down the sink because I can't stomach the sour yucky taste

Michael
 
Is it the same batch of grain if so it seems to me too that that could be the cause of infection as you seem to have eradicated all other contaminants i.e old FV's that still carry the posssible infection and equipment. I would bin the rest of the grain and replace it now. Just one other thought if you use equipment that comes into contact with grain that has not been mashed and use it in the wort/beer at a later stage this can also transfer the infection from raw grain too so do not use jugs spoons etc for raw grain and use later in the brewing process to eradicate this too
 
Thanks for your speedy reply. I've used 2 different types of grain although the only 1 I have used on it's own is the marris otter. Even when using the lager malt I used a bit of marris otter so thay could be the issue! I will scrap it and see how I get on
 
This is very mysterious. Everything you describe in your method is just as it should be. And if your kit beers using exactly the same equipment are ok then it must be the grain. Even if there were residual starch from an incomplete conversion, it wouldn't make your beer taste sour, it would just be cloudy,
A couple of questions before you jettison your grain, and I agree with the Baron, above, that that's the most likely source of your problem:
  • When do you notice the sour taste? Does it taste sour as soon as you've boiled the wort or does the sourness develop? This can be difficult to discern as the sugar in the wort will tend to mask any sourness.
  • Try tasting your malts. Do any of them taste noticeably sour before you even start mashing?
  • Are you adding Acid Malt to your mash to correct the pH?
  • Do you mash and boil in the same vessel as you make your kits or do you make up your kits directly in the fermenter? Is your mash and boil vessel made of stainless steel?
It would be a shame to give up on all grain. This sourness thing is really unusual.
 
Hi Ankou there is a contamination of raw grain to the wort/beer I have read about it and it says not to use the same equipment for the raw side to the brewed side I can not remember what it is called and have searched the internet to no avail but I know I have not dreamed it. I am sure somebody with a scientific approach will come forward with the answer
 
Welcome to the forum !
I hope you can sort out the problem, could it be related to your water. We have soft water here in Manchester so never had a problem with PH, but it may be worthwhile getting a report from your water Co. And do use a Camden tablet to remove the chlorine from your strike water.
Cheers
 
Hi Ankou there is a contamination of raw grain to the wort/beer I have read about it and it says not to use the same equipment for the raw side to the brewed side I can not remember what it is called and have searched the internet to no avail but I know I have not dreamed it. I am sure somebody with a scientific approach will come forward with the answer
Grain naturally contains lactobacillus, so it's not advisable to use your fv to measure grain into.

@Michaelmacd Is the beer sour, as in vinegar or unsweetened Yoghurt? I'm wondering if thats definitely the sensation or whether it's an astringent sensation, like sucking on a teabag.
 
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Yeah Sadfield finally found it, just couldn't remember which it was and it does seem to cause a sour taste as in Belgian Lambics. It is the Lactobillus that is used to sour milk into yoghurt etc so could be the answer of raw grain contamination to the beer?
 
Hi thanks again for replies.

To answer the questions.

I'm not sure where it appears to be honest I've never noticed it when tasting the wort pre fermentation but post fermentation yes.

I havnt tasted the grains pre mash nobut I will do. Is there anything I should notice?

I think I will need to look up acid malt as I havnt been paying any attention to the ph of the mash. I'm guessing that could be a major downfall for me! I've been using the marris otter or lager malt straight into the strike water without any additional malts.

I have been mashing an boiling in the same pot. It's just a 21 litre stainless steel pan.

As far as I know my water is good although I've never had a report on it. I'm in the highlands of Scotland and it's very drinkable and soft around here. I guess this could effect ph of the mash even more not knowing what I started with
 
I think boiling will kill the bacteria it is contamination after boiling that is why most brewers do not use FV's to store grain as it can contaminate the FV which never gets boiled to kill it off. Ph levels are important and certain bacteri/infections breed at different Ph's so just scrutinise your method and I am sure you will overcome. I am lucky and have never had a infection but did have a astringency in a few beers caused by Ph levels which I got sorted . I too was at a loss but eventually with reading and help from the forums bottomed it
 
Hi thanks again for replies.

To answer the questions.

I'm not sure where it appears to be honest I've never noticed it when tasting the wort pre fermentation but post fermentation yes.

I havnt tasted the grains pre mash nobut I will do. Is there anything I should notice?

I think I will need to look up acid malt as I havnt been paying any attention to the ph of the mash. I'm guessing that could be a major downfall for me! I've been using the marris otter or lager malt straight into the strike water without any additional malts.

I have been mashing an boiling in the same pot. It's just a 21 litre stainless steel pan.

As far as I know my water is good although I've never had a report on it. I'm in the highlands of Scotland and it's very drinkable and soft around here. I guess this could effect ph of the mash even more not knowing what I started with
Don't want to confuse the issue, if you're not using acid malt then don't worry about it. If you did chew on a few grains you'd know because it would be sour.
 
The sourness is sort of like sour yogurt I guess. It's kind of hard to describe. It's definitely not sharp like vineger.

I will need to investigate ph for sure!
 
We have a consensus, Sadfield and The Baron. I suspect lactobacillus, too. I asked MichaelMacd to taste his malts for just that reason. The Bavarians encourage lactic acid in one particular kind of malt so that they can acidify the wort and correct pH without falling foul of "purity laws" by using chemical additives. Hence my question about Acid Malt.
All we need now is for MichaelMacd to come back to us and say that all his malts taste sweet and lovely and we're back to square 1.
The Baron, I feared you were going to mention St Anthony's Fire. An infection in wheat and barley dating back to mediaeval times causing hallucinations and even death.
 
I'm wondering if it's something to do with the cooling process as this will be the big difference from extract brewing (presuming with extract you just topped up with cold water rather than having to do the full-volume cooling process)? Maybe its getting infected at this stage? Or you didn't cool enough and pitched the yeast too hot?

I had a few issues like this when I moved from extract to AG and came close to giving up AG. My suggestion would be to stick with it, try a really simple recipe and maybe smaller volume, to get your process right. Maybe a simple SMASH.

I was pretty under-whelmed when I moved from extract to AG, coincided with a few issues and infected brews that I'd never had before.
 
The sourness is sort of like sour yogurt I guess. It's kind of hard to describe. It's definitely not sharp like vineger.

I will need to investigate ph for sure!
And the sourness in sour yoghurt comes from lactic acid!!
Do as The Baron says. Jettison the malt, buy some fresh. Start over again.
 
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