partial mash flavor problem

[malcontent40]

It seems whenever I do a partial mash(2 gallon cooler 4lbs. of grain) about a month after I bottle my beer develops a bitterness to it. It almost seems like it is going stale but it only gets a little bitterness and it doesnt get worse. You cant smell it either. And of course it is more pronounced in the lighter beers I have brewed this way(a cream ale and a pale mild ale). Is it maybe the wort is splashing too much when I run off oor do I need to increase my boil time from 60 to 90 minutes?
Thanks for any help

 

[HopHound914]

Depending on how your sparging these grains or at what temp you could be extracting harsh tanins that will give a very bitter taste in some instances. Just a thought.

 

[malcontent40]

I thought that as well. I just do a slow run off in to a measuring cup recirculate a few times and drain the cooler. I refill the cooler with my sparge water and let it sit for 5 minutes. I even lowered the temp of my sparge water to 160 F . The Beer tasted awesome for about 2-3weeks after priming then this bitterness occured. The bottles seem sealed well.I store them in the basement in the dark at 65 F then throw them in the fridge when Im ready to drink.

 

[RM-MN]

What is your mash pH and what does it get to during the sparge? If it gets too alkaline, you will extract tannins.

 

[captainL]

My thought is that your water has a lot of bicarbonates maybe. I'm new but I have kid of experienced this too. When my beer is green it tastes fine but as it ages there is a little of a harsh bitterness coming out. It could be from the tanin's too but I haven't exceeded any limitations with the ph and temps so I think I have it narrowed down to the water for myself. i also just cooked up my first all grain. Maybe it is also just an extract twang?? I guess I'll know soon. Those are my thoughts, but I am only on brew number 6 so.....

 

[malcontent40]

Maybe it is my mash ph. I never tested it . I always use bottled water which I thought was kind of neutral. What kind of numbers do I have to stay under?
The only other thing I can think it may be is when I chill the wort . I use an imersion chiller that I put in the last 5 minutes of the boil to sanitize. But when I am chilling the wort I do stir it kind of vigorously. Maybe I am getting some DMS from oxygen in the hot wort?

 

[WheaYat]

are u moving the carboys any after fermentation? i remember readin in palmers book that even handling the wort improperly can cause oxidation to the final product. maybe oxidation can be ur problem? just a thought.......

 

[reim0027]

From what I know, your target pH is somewhere around 5.2 I don't know the answer to your main question however.

 

[malcontent40]

Thanks for the help. Its a tough one I know. Since I didnt have this problem when I did extract with grains Im thinking of looking into my mash ph.