off-flavour

[crow_flies]

I've brewed many all-grain recipes (bitter styles), I get good conversion, clear wort, good boil, both breaks are good and good clean fermentation. Beer tastes fantastic when it goes into 2ndory, but then it often gets an aftertaste which is not pleasant, it did disappear after a few weeks cold conditioning - are these normal heavy alcohols that get broken down after time? or am I doing something wrong. I've read references on off flavours, all I can say is it isnt in the inital taste, it comes on after its swallowed - chemicalish/pear/apple I guess.

interestingly I recently tried to copy the delicious palmers dorset gold with just pale malt - that was perfect - used challenger hops - not too much in the boil, generous in the 2ndory.

/crowflies

[crow_flies]

thanks daab,

i do boil the water for 15 mins prior to the brew and use CRS and DLS according to my water levels in south london (very high alkalinity). the flavour isnt there in primary - sips i've taken at that point taste great - the flavours seems to develop over a couple of weeks, I did wonder about temp. I think I've been brewing too warm, so I'll try that and also a cold spell in 2ndry to see if that helps....

/crowflies

[crow_flies]

I'll definitely try that - good point. I just poured one i bottled 6 months back - it was a bit rough early on, but it definitely does not have any off flavours now.......

[Andy]

CF - would you mind taking us through your brewing process - the kit you use and how you transfer wort around from stage to stage ?

[crow_flies]

Ok its pretty heath robinson......

I normally boil 25ltrs water for 15 mins and adjust the alkalinity at that stage. I mix 1/2 dls into my grain and then pour boiling water into a large converted picnic box (colemans) which I brough back from the far east. Its massive and can easily mash 6-8 kg. I built my own tube filter which is large bore copper pipe in an oblong shape with cerrated cuts about 1/4 inch spaced all around.

I wait for the water to hit about 72c then gently mix in the grain. this normally drops it to about 66-68c - i target 67 cos I like some residual sweetness. I shut the lid at this point - its normally saturday afternoon about 1ish - lean over and crack open a bottle from the fridge......

I leave this for 1.5 hrs and menwhile boil another 20litres water and treat in same way.

I test the mash with iodine to check conversion has completed and then pour into a sanitised bucket (pouring the first few back trhough). I used to sparge, but now I've taken to doing a second mash and using this to add to the first to get 20litres for the boil.

I boil for 15 mins until i see the froth subside and then add hops per recipe. 15 mins from the end i add finings and put the copper coil heat exchanger in (having wshed it off first). time for a 2nd or 3rd bottle.....

I take a sample of the wort about 15 mins from the end and cool this to pitch the rehyddrated yeast into.

once the wort is cooled to low 20s I pout into fermenting bucket (i agitate the first pourings vigourously to aerate) and then I pitch yeast. I clip on lid and attach bubbler with sanitised water in it.

I've tried a variety of ways of fermenting periods. 4 days then to secondary, 1-2 weeks and then to barrel etc. at this stage I always transfer via a length of sanitised tube to ensure i dont splash it too much.

One thing I dont have in secondary is a scretop fermenter, so i wondered if the clip on lid bucket and bubbler for secondary was perhaps part of the problem (too much head space??)

After 2 or 3 weeks if I have used a secondary stage I then transfer the liquid from secondary to sanitised barrels or bottles.

I normally try and leave it 3 weeks or so before sampling.

I do brew in a shed, so i expect the high temps have had some part in producing too many fusel alcohols which can contribute to off flavours plus the lack of enclosed secondary perhaps?

my latest i moved to barrel after 4 days as an experiment and the off flavours are less prevelant after 3 weeks but could also be the lower temps we have now???

think that cover all?? any hints welcomed.....

/crowflies

[crow_flies]

sorry boiler is a normal plastic bucket with single kettle element, 30litre bcukets with close fitting lids and airlocks, numerous 'oldish' barrels - the old red and brown ones that boots used to sell

mash tun is adapted cooler box - i'll pos pics when i can work out how.....

[mysterio]

Sounds like your fermentation temperatures are too high, try moving your fermenter to a cooler part of the house?

[crow_flies]

you could be right there - now things are cooling off shed should be ok, also got a lean to beside it that is a few degrees cooler. I read in HOW TO BREW about using a tub of water to put the fermenting bucket in, theory being that the cold water jacket around it stabilises the temps when the weather is warm - may be a good tip for next summer!!

/crowflies

[NzDan1]

I have had off flavours from cheap and nasty fermentors with big rubber seals in the lids, the rubber seal has an undeniable strong rubbery chemical odour which I can smell through a plastic bag, it had badly tainted a few brews before realised what was causing it, the smell even permeated into the plastic of the fermentor.
I dont use fermentors with smelly rubber seals anymore!

[crow_flies]

It was the chloromine..... I followed Daabs advice the centennial brew that is just drinking now definitely does not show any signs of developing the off flavour. I serched google and as far as I can work out they do use chloramine.....

I'm pleased as punch to have cracked it....

/crowflies

[crow_flies]

1/2 crushed campden tab that is....