Correcting Astringency

[Virginia_Ranger]

I have a finished Porter that doesn’t really appear to have an infection but I think the speciality dark grains are causing a little astringency. It’s not bad or makes it undrinkable but it’s there if your looking. I am thinking about adding some Lactose to it sweeten / cut the slight pucker. Does that sound reasonable?

 

[SoCal-Doug]

I'll assume that you are doing all grain, and when you say "astringent" you do not mean tart/sour and do mean something like sucking on a tea bag, chewing an aspirin, or drinking a really crappy cheap merlot. here's a few topics that can lead to astringency...

* letting the grains get hotter than 170 at any point in the brewing (mash, mashout, sparging)
* mash pH too high
* oversparging (grain pH creeps up)
* choice of dark/roasted grains (some are mild, some are like God awful burnt sugar)
* pushing the edge of anything above in combination with over-milling where husks get pulverized
* water chemistry
* Stirring too much or too hard during mash
* low quality hops

If it is polyphenol related, you might be ok after some aging as they might partially sink out. If you had a good hot break, cold break, and other processes were suitable for them to bind and precipitate. Two things I might try would be (1) cold crash it then use gelatin or (2) biofine liquid. No guarantee but it may help. I would not back-sweeten it.

 

[Virginia_Ranger]

Thanks for the reply! I did a partial / mini mash BIAB and in reply to your topics above:

1. I mashed out right around 170, I could have gone up to 171, 172 which could be the issue

2. not sure on PH

3. No Sparge just let it hang and drain

4. Please see grain profile below!

5. To be honest I think my LHBS when I have them mill it over mill it a bit

6. Water Chemistry should have been good same profile as multiple none astringent batches

7. No stirred during mini mash

8. Hops should have been good as they were pretty new

Grain / DME Bill:

FERMENTABLES:
3 lb - Dry Malt Extract - Light (36.4%)
2 lb - Dry Malt Extract - Amber (24.2%)

STEEPING GRAINS (mini mashed at 148 - 150 F for 35 min):
1 lb - United Kingdom - Pale Chocolate (12.1%)
1 lb - German - Carapils (12.1%)
1 lb - American - Caramel / Crystal 60L (12.1%)
0.25 lb - American - Chocolate (3%)

HOPS:
2.5 oz - Fuggles, Type: Pellet, AA: 4.5, Use: Boil for 20 min, IBU: 24.14

 

[SoCal-Doug]

I see nothing obvious for a cause of astringency. Possibly the darker grains with an unknown water chemistry profile. Not quite raising my eyebrow about that though. If you squeezed or twisted up the steeping bag or tried to compress the grains to get extra wort, you could have released some tannins. But you said you just hung it and let it drip.

If it has not been kegged or bottled yet, keep it sealed put it in a fridge for a couple days and get it down below 40F (or as cold as possible). Then mix a teaspoon of plain unflavored gelatin with 150F water and stir until dissolved. Let that cool to room temp, then add it to the beer and stir well. Leave it alone for a week. Then bottle or keg. If its kegged, you can put the gelatin into the keg and do the same thing. If the proteins bound well with the polyphenols, the gelatin might get some of it to sink out.

If its already bottled, chill it as cold as possible (not below 32F of course). when you pour it, pour carefully without bubbling so the schmutz at the bottom doesnt go into the glass.

My hunch is that it simply needs a little aging.

Just out of curiosity, what yeast did you use?

 

[RM-MN]

Random thoughts that might help for this batch and future.
1. Time is a wonderful thing for beer. I usually don't even sample my porters for a couple months and find that they are still improving. Your porter probably mostly needs more time for the harsh flavor particles to settle out.
2. A mini mash requires a base malt that has diastatic power (words to look up for definition). You had steeping grains, not a mini mash.
3. With BIAB a mash out isn't needed. Skip that next time.
4. When you make a batch where there is a base malt, sparging will help collect more fermentable sugars. It won't do much when there are no base malts though. With BIAB sparging can be done by simply pouring fresh water over the hanging bag. No heating is required as cool water works about the same as hot.

 

[hottpeper13]

TIME (what RM-MN said) I have found the mash pH plays a big roll in when can I drink my dark beers. If I mash at 5.2-5.3 my porters,stouts and dark to black lagers take about 12 weeks to come into their own. When I mash at 5.4-5.6 they fall into line with most of my 4-5% beers which is ~6 weeks GtoG. About a year and a half ago I built a conditioning chamber with CO2 and have it set to 33*. I put all my beers in there for at least 2 weeks. It is so cool to take an empty keg out of the kegerator,and replace it with one that's 100% ready to go! Just do that relaxing thing for awhile,the colder the better.

 

[Virginia_Ranger]

Thanks for all the input, all very helpful! For what RM-MN said about the mini-mash needing a base malt, I usually add about 1/4 to 1/3 of my DME before adding in the grains in the bag, would that count as a base?

 

[Virginia_Ranger]

I see nothing obvious for a cause of astringency. Possibly the darker grains with an unknown water chemistry profile. Not quite raising my eyebrow about that though. If you squeezed or twisted up the steeping bag or tried to compress the grains to get extra wort, you could have released some tannins. But you said you just hung it and let it drip.

If it has not been kegged or bottled yet, keep it sealed put it in a fridge for a couple days and get it down below 40F (or as cold as possible). Then mix a teaspoon of plain unflavored gelatin with 150F water and stir until dissolved. Let that cool to room temp, then add it to the beer and stir well. Leave it alone for a week. Then bottle or keg. If its kegged, you can put the gelatin into the keg and do the same thing. If the proteins bound well with the polyphenols, the gelatin might get some of it to sink out.

If its already bottled, chill it as cold as possible (not below 32F of course). when you pour it, pour carefully without bubbling so the schmutz at the bottom doesnt go into the glass.

My hunch is that it simply needs a little aging.

Just out of curiosity, what yeast did you use?

Plain ole Us-05 dry yeast

 

[RM-MN]

Thanks for all the input, all very helpful! For what RM-MN said about the mini-mash needing a base malt, I usually add about 1/4 to 1/3 of my DME before adding in the grains in the bag, would that count as a base?

No. What is needed is a malt where the enzymes are intact and ready to convert the starch to sugar. That's why I suggested you look up the definition of diastatic power. Base malts would have names like 2-row or pale malt. The DME has been heated to boil and that destroys the enzymes.

 

[Virginia_Ranger]

Thanks! I read up a little bit, what quantity or percentage on average would you need of the base to get the diastatic power? Could that just be in incorporated in the bag with the other grains?

 

[RM-MN]

Most modern pale malt has sufficient diastatic power (enzymes) to convert itself plus about twice its weight of unmalted grain. The conversion enzymes need the temperature of the mash to be in the range of about 148 to 158 F. Too cold and different enzymes will be at work breaking down proteins or creating acid, too hot and the enzymes are destroyed. For a typical mash all the grains are mixed together. One untypical is to steep the dark or roasted grains separate in cooler water to avoid the harshness they can give.

 

[SoCal-Doug]

This has nothing to do with the O/P question about astringency, but...

Carapils, crystal 60 and chocolate have zero diastatic potential. The kilning process has destroyed the enzymes. The pale chocolate has a lower DP than regular pale malts.

Depending on the brand of the DME, it may or may not have any diastatic potential. A few brands add enzymes back in, most dont. The process of making DME and LME destroys the enzymes.

If your recipe needs more DP than it provides you can (1) change the recipe to use higher DP grains or (2) add enzymes during the mash.