all grain brewing problem

[Dr. Dextrin]

Maybe I've misunderstood, but I gathered that the beer in your barrels was progressively getting sourer, whereas the stuff in bottles wasn't. I'm not sure now how that squares with the beer keeping well in your barrel for 6 months.

It's probably true that you only get that cardboardy taste if you grossly oxidise the beer by letting air glug in. The yeast will devour a certain amount of oxygen, as will other reactions. But the taste will still change even if the oxidation is at too low a level to taste cardboardy. A general dullness of taste and progressive sourness is characteristic of this, although stronger ales tend to stand up better.

The rate of oxidation is the key issue and larger barrels, even if made of wood, could be fine simply because of the large volume of beer relative to the surface area. With a 5-gallon batch it's a little more challenging, although keeping the vessel full helps. Possibly, if the oxidation rate is low enough the beer may actually benefit (like maturing a wine) but I've never experienced this, maybe because my barrels never stay completely full for very long.

Or maybe you've got really good barrels that keep oxygen at bay for at least 6 months. If so, I'd like to hear more...

[gnorwebthgimi]

It's interesting that we don't have the same experiences and I'm eager to learn anything you know that I don't.

There are probably a few things that I haven't disclosed that may have lead to the misunderstanding and one thing that may interest you:

With my initial AG beers I didn't have a cooler and I just let my beers cool overnight in the fermenter before pitching the yeast, which leads to massive alpha acid conversion and very bitter beers.
Bitter beers (like original recipe IPA's) are designed to stand up long storage times and are good at keeping a long time, so this may be why some of my earlier beers kept longer.
But the kit ales also kept and these lacked bitterness if anything.

The beers are also over carbonated which may make it harder for oxygen to diffuse into the beer.

The "sour" taste presents after a week of barreling and get progressively worse until two weeks when it stays pretty much the same (no significant variation that can't be put down to age). I guess it could be oxidation, but I have tried in the past to rule this out.

I will bottle a batch of the new beer and see if the bottled variety keeps better and report back!

[Dr. Dextrin]

So you seem to be saying that since you started force cooling your beer it hasn't been keeping as well. FWIW I always cool my beer slowly in the FV, so whether that's good or bad, it doesn't explain the differences we see as mine generally doen't keep for anywhere near 6 months. I don't recall my kit brews lasting any better, either, although it's been a while since I did one of those.

Also, the level of carbonation, contrary to what you might expect, doesn't affect the rate at which oxygen can diffuse in. That's determined by the difference between the oxygen pressure outside and inside. The latter is always near zero because beer absorbs oxygen like a sponge.

If the sourness you're experiencing starts after a week and stops after 2 weeks, then it sounds to me like it's just the effect of some of the residual sweetness in the beer fermenting out. Sweetness can mask a variety of ills, so it may just be that the increasing dryness is exposing some harshness that was always present. I find that even bottled beers go through a low point at this stage, when they become dry enough to expose any harshness that will later fade as the beer matures more.

But I assume your gravity reading of 1005 wasn't after just 2 weeks was it (that would be surprising)? I've recorded similar gravity drops in my barrels, but only after many weeks when the beer was essentially undrinkable due to slow oxidation (and fortunately not much left). I don't know what the mechanism is, but the staling of the beer often seems to be accompanied by a gravity drop IME.

[gnorwebthgimi]

The beer did ferment down to below 1.005 within two weeks of barrelling, which I was surprised at, it seemed stable at 1.010 before I barrelled it.

Hopefully the sample I bottle will expose any problem with the barrel, but I still suspect gravity is part of the problem.

In the meantime I might take a sample and deliberately let it oxidise and record the results.

I will let you know how well both samples keep (barrel and bottle).

Thanks for the input!

[gnorwebthgimi]

The new brew has been fermenting five days now and fermentation appears to be subsiding, the gravity is 1.019. (so far an attenuation of 62%)
The last beer fermented from 1.038 to 1.010 in the same time period (74% attenuation) the mash temperature was 2'c different.
So it looks as if my higher mash temperature has created a less fermentable wort as it should have!

Given the last beer dropped more gravity in the barrel and I can't pin this on highly fermentable wort I'm now suspecting a stubborn wild yeast infection or lactobacillus.
I have been anal about sanitisation thus far and I am currently doing an initial sanitisation of the barrel and siphon. I will sanitise them both again before I transfer to barrel and take a sample for bottling.

This will rule out infection and oxidation.

If this fails then it must be water treatment or angry gods.

Thanks for the help everyone, I will keep you all posted.

[Jim]

Here's my 2 penn'orth (admittedly I've only scanned the thread quickly):

1. forget about hot side aeration (it is a myth)

2. Forget about the blaming the plastic barrel (plenty of people including me have kept beer in them for 6 months without problems)

Concentrate on the gravity drop in the wort after kegging. I've had a similar thing happen to some of my AG brews; the maltiness that balances the hop bitterness reduces, and the beer gets more bitter (bitterness and sourness are both associated with acidity). This is likely to be down to the mash conditions; prime suspects would be temperature and pH (the pH being down to your water and any water treatment and the composition of your grist).

I don't see any reason why you should be getting wild yeasts in your AG brews and not kit brews - if anything AG should be better as all the liquor is boiled.

[gnorwebthgimi]

Hi Jim

Don't blame you for skim reading this rather long thread.

Agreed about HSA, I came to this conclusion with the last batch of beer.

I think I'll still take a sample in a bottle, it will be interesting to see how or if it varies.

With regards the current brew I think the mash went better and I'm much happier with the FG being at about 1.019, from what you're saying this will mellow to a nice level in the barrel that will balance the hop bitterness (in theory, it should be too sweet at present). If it drops to say 1.014 (five points like the last beer) then it should be fine.

I might do a calibration test on my hydrometers (I have about 8 because of a variety of donations, but I only use the same one), if this turns up anything I will let you know.

Hoping for the best with this brew as there is still plenty of time to brew before Crimbo. 5 gallons of homebrew makes a good gift to right recipient

Thanks again

[gnorwebthgimi]

The new beer is in the barrel.

I had a look over my notes, it's not the highest FG I have had but, the highest FG I had was the best beer I made according to my notes.

I took another sample of the last beer from the barrel and bottled it with some dark sugar. Tasted nice after a few days (not brilliant but good) from which I can only deduce that low gravity is my issue.

Hope this beer stays reasonably high gravity.

[jat147]

...wind ... piss*ng

[gnorwebthgimi]

P1ssing in the wind I might be. But if you don't try you will never succeed.

So far the new beer tastes young (which it should). Normally they don't taste young, they taste at their best straight out of the fermenter, so I'm taking this as a good sign.

[Jim]

I also find higher gravity beers easier to get right. The alcohol provides some of the balancing sweetness.

[Northern Brewer]

Just thought I'd add my two-penneth worth...

Personally I suspect that you identified the culprit in your opening post, namely S04.

There is no doubt that some people are more sensitised to the sourness that this produces, and I count myself amongst them. I was content to use it for years, and always blamed the mouth puckering hint of sourness on the hops. This always became more obvious as the beer matured and the other flavours became cleaner. Is was also less obvious in bottled samples, presumably due to the additional carbonation masking it.

Once I'd become aware of the sourness it eventually became impossible to ignore, so I made a brew with Nottingham by way of comparison. Loh and behold, the sourness was gone, but the blandness of Nottingham was immediately apparent. I was immediately persuaded to move on to liquid yeasts with great success.

Loads of people get on famously with S04, but I'm afraid that I shall never return to it.

[Fallen]

Have you checked your mash pH?

The reason I ask is that I've gone back through my notes and now suspect that acidity is my main problem. My last couple of mashes have been in the 4.6-4.9 range (way lower than I wanted....obviously). Slowly, the penny has been dropping that this may be my primary problem of late.

I found this post on Homebrewtalk.com which has absolutely NAILED the characteristics of my recent brews:
The average beer pH is in the low 4.Xs. The pH of the solution, from liquor to beer reduces throughout the process. You'll see it stated on here that the pH of the brewing liquor doesn't matter, that it's only mash pH that matters. This is an overstatement at best. The pH of the liquor does matter, especially if it is in an extreme range. For example, if your water pH was already 5.5, and you brewed with dark grains, the pH would likely go lower than than the optimum range, resulting in increased enzyme activity that breaks down insoluble protein and decreased enzyme activity that would have broken down starches, resulting in a hazy beer with lowered foam stability and increased sourness due to the lower final beer pH.

Head retention, haze and sourness have been my main problems of late!! Having gone through my notes, I realised that the change in quality of my beers is correlated exactly with my change in water treatment regimen. Previously, I added the appropriate amount of CRS and a teaspoon of gypsum directly to the HLT. The change happened when I started adding the teaspoon of gypsum directly to the grist/mash, thereby significantly increasing the Calcium ion concentration in the mash, which I understand can significantly lower the pH (although I won't pretend to fully understand why; presumably some effect on buffering capacity).

Just thought this might be relevant to your tribulations.

[coatesg]

It'll make a bit of difference as you'll have more calcium ions to react with phosphates from the malt (which is where the pH drop comes from via: 3 Ca (2+) + 2HPO4 (2-) -> 2H+ + Ca3(PO4)2 - the H+ ion increase will result in pH decrease by definition). But, I'd be surprised if an extra half teaspoon in the mash will actually make enough difference to drive the pH down to 4.6 - I don't think it is that easy to affect the pH in such a big way with a few grams of CaSO4.

My guess would be that in fact you're either overdosing on CRS in the first place, or maybe your water has changed to how it used to be. What rate are you adding CRS? (My water is almost the same as yours and I know what my additions are, and I don't tend to get sourness or any of the other issues).

[Fallen]

I did a brew last weekend so I'll give you an outline of my method.

The recommendation from Brewlabs was to get the alkalinity to 30-50 ppm for a Burton pale ale. I measured alkalinity and got ~165 ppm using the salifert kit and calculated the amount of CRS to target 40 ppm as 17.3ml CRS for 25L of strike water. As a belt and braces approach, I then measured alkalinity of my treated water after CRS treatment; 40 ppm spot-on.

Brewlabs recommended mineral additions of 12g gypsum, 10g dihydrate and 8g epsom to be added to the grist. I did this and measured mash pH (albeit a bit later than I probably should......40 minutes in) and pH was in the 4.6-4.9 range using pH papers.