milling grain too fine?

Troutchaser · Apr 5, 2015

Happy Easter all! So I'm a newer biab brewer and I have heard that crushing your grain very fine helps a lot with efficiency. So I have been having my LHBS mill my grain twice to get it finer. The problem is I have been getting some off flavor and it's getting extremely frustrating. I apologize for not being good at decribing the flavor I'm still very new but it kinda taste like it's still really green even though I leave them in the bottle for over a month. My question is can this be because my fine crush? I clean and sanitize with star San like a crazy person so I don't think it's getting infected! Anyone else have an issue like this? It's happen three times now and it's very frustating at the end of the whole thing the beer turns out not so good! Thank for any help you can give me.

Spectre216 · Apr 5, 2015

The only off flavor i'd think you might get from too fine a crush is tannins, but even that I think is more a factor of PH and temp then it is of crush. I'd guess it might be else in the process. What other information can you give us? How long in the fermenter? Mash temp? Recipes?

Troutchaser · Apr 6, 2015

Dang I was hoping it would be easy! The mash temps depend on the recipe but it's happend on pale ales and ipa's and I hit my numbers right on the dot! I ferment for three weeks then bottle for 3-4 before drinking. I just got fermentation chamber with temp control set up so maybe this will help. Before I just put the carbon in the closet and kept the house at 70 .

Magnus314 · Apr 6, 2015

Make your next batch with a single pass grind and see if it has that taste.

Fermenting IPA's at 70 will give weird flavors from the yeast. Don't know if that's causing your "green" flavor, but it definitely could be.

brewkinger · Apr 6, 2015

Agreed that we need to know more about your process.
At first glance, fermenting at 70 degrees means that the beer could be as much as 7-10 degrees hotter.
This creates fusel alcohols that taste "hot".
What kind of water do you use? You mention hitting your temps spot on which always reminds me of my thermometer being off by 4 degrees and my "spot on" was a spot off.

Tannin extraction tastes like you have a teabag in your mouth and it is a result of pH more than anything else.

The fine grind most likely is not the problem, but single grind your next batch and see if there is a difference. You can bump up the grains to offset the efficiency loss.

Walk us through your process from start to finish and spare no details?

The_Bishop · Apr 6, 2015

BIAB makes your source water even more important, because it's a larger volume you're mashing in and therefore has more buffering capacity. If it's alkaline, your mash PH will be too high and that could be causing tannin extraction. Also, if you heat your mash at all, you need to stir, or it'll overheat on the bottom, which can cause scorching or tannin extraction due to PH and temperature.

Troutchaser · Apr 6, 2015

I buy spring water from the store I have never tested it but assume it would be fine. It could be that the beer was getting to warm in my closet. I now have temp control and have a Pliny the elder in it now so will see soon. Thanks for the help I do appreciate it. I will have to post my whole process when I'm not on my phone.