Bitter aftertaste in beers that were great earlier

I have brewed 5 extracts and 1 cider so far. My first was great, still down the the last few bottles. My second was a Caribou Slobber, third was a cider that I haven’t gotten to try yet, fourth was the Milk Chocolate Stout and the fifth was a Bavarian Hefeweizen.

Trying to give enough information:

Caribou Slobber
Bottled May 29
4.06% ABV

Milk Chocolate Stout
Bottled June 24
3.84% ABV

Bavarian Hefeweizen
Bottled July 1
5.68% ABV

As time goes on they all have become bitter in the back of the mouth right before I swallow. At the beginning they are fine. I first noticed the bitterness when I was having a Hefe and that is was different from the last few I had, it still isn’t bad, just more bitter. The Caribou now I had to dump, I couldn’t take the flavor any more, but it was fine with a hint of bitterness about 2 weeks ago. I am drinking the Milk Chocolate Stout now and it isn’t as sweet as it was, but more bitterness then before. It is still good, but not as good as before I think.

Everything has been stored in the same location about 68 degrees. When I go to drink it, it is in the fridge for at least a few days.

Any advice would be appreciated.

Maybe the temp went high on steeping specialty grains. I think you can get a bitter back of the throat taste from stuff that comes from the husks if temp goes too high. I made a hefe that was that way - taste was good, but bitter in the throat after swallowing.

I wonder if you do not have some kind of infection that is causing off flavors over time. The reason I suggest it is:
1.) You say the beer is good at first, but gets worse over time.
2.) The beers you brewed are not “hoppy” beers, so it is not like there are lots of hops that are causing the problem or getting harsh over time.

What are your sanitation practices?

Other thought - water maybe? Do you know what is in the water you are using? Sometimes if you have really hard water and brew with extract you get a double dose of minerals (extract already has minerals in it from the process used to make it.) Often suggested just to use RO or Distilled water with extract.

Thanks for the feedback.

The steeping may have contributed to the Caribou Slobber since I did steep to hot, then I read more on it and learned. Sanitation I am pretty anal about, especially at the beginning. I was filling the carboy filled with Iodophor at the start until I learned a little goes a long way.

I am considering that I had an old charcoal filter.

viewtopic.php?f=1&t=110341

The reason I am considering this is that I used tap water my first batch and bottles still taste fine. I know that the filter was old (it just got changed.)

My question is for those that have experienced the water filter issue or know about it. Does your beer taste fine at first? Why would certain beers taste bitter faster then others?

That change over time makes me think it’s an infection too. I had that happen with a mild before. It was a batch where I had just gotten some flip-top bottles I wanted to use and went quicker through the cleaning process than usual. Especially if your beer went from good to undrinkable, that’s a slow moving infection rather than the water. Normally any issue with the actual brewing of the beer will either stay the same or mellow over time (that I can think of right now, the only exception would be if hops mellow allowing you to taste an off-flavor that you didn’t notice before).

When you dumped the Slobber, did it seem more carbonated than before? If bacteria is eating away at it, it would probably increase the carbonation as well as that bitterness you were describing.

No increase in the carbonation, but I will be more mindful to pay attention to that. I am having a Caribou Slobber now from the same batch and it is faintly bitter, but drinkable. It seems isolated. I have bottles stored in two different locations. Could temperature fluctuations cause this? If it is an infection and one location is warm, I assume the infection would spread faster?

I would assume so about the temp but not sure. It might have to do with how clean the bottles were as the infection source if there’s some affected but not all.