Diagnosing the wrong bitterness

[northernlad]

I have about 10 AG batches completed so far. In my last 3 or 4 batches I have noticed a bitternesss that is very much like an oversteeped tea bag.

My process:
I use an unmodified 5 gal round cooler with a strainer bag and batch sparge. As a result my grain bill is at the most 12lbs. I fill the mash tun to 3 gal, add the grain then top off. Mash for 60 minutes at 152-154 then sparge. For the offending batches I did not pay particular attention to sparge amounts or temperatures.
Since I discovered the problem I have paid more attention to sparge temperature and quantity. I am mashing with 4 gallons and sparging with 4-4.5 gallons (170*) to collect 6.5 gallons.

I have yet to bottle since I changed my procedures and was curious if I am on the right track to correcting the problem.

 

[Funkenjaeger]

I don't have any specific recommendations based on your process, but just to give you a search term to work with, "astringency" is the term for what you describe.

 

[suprchunk]

Sparging too hot, would be the easiest guess from what you lay out in your steps. Since you don't pay attention to the temps. Leeching too many tannins. Or you are running off too much during sparge, again leeching too many tannins. Or at least that is my impression.

 

[pjj2ba]

If your water has high carbonates (temporary hardness), this can cause an astringent bitterness in well hopped beers. Treating your water (or changing sources) should take care of the problem

 

[northernlad]

Thanks for the input,
I am aware of astringency, I have just seen it used alot and the OP is always asked to qualify it so I thought I would describe the flavor instead.
I am sure my failure to pay attention is the cause and I hope to see an improvement in the two batches I have fermenting.

I have yet to get real water numbers, but i am pretty confident hardness is not a problem. We drink God's water here.

 

[dantodd]

Another possiblity when using a strainer bag is that you are squeezing the liquid out of the bag rather than just letting it run out under gravity alone. I have heard this can extract tannins too.

 

[northernlad]

I am very careful not to squeeze the bag but I let the runnings flow as fast as they will come if that is important.