Astringency killer?

[Fore]

Hi guys. Although it's often said it's difficult for home brewers to suffer this, I'm definitely suffering.

I'm wondering what will be the single most important thing to kill this off once and for all?

Info:
Grainfather fly sparge. I acidify all my pH7.2 liquor, which means my sparge water is somewhere about pH6.7. I know that's higher than the recommended pH6.0, but I ensure it's less than 78C (@75C). I thought you needed both high temp AND high pH to risk tannins, but it seems not. I measured my final runnings and a drip came in at 1.007, but when gathered in a bucket it read 1.013.

I don't want to reduce efficiency by reducing sparge water temp if I can help it. For my last brew I acidified my sparge water to see if things improve. Still in fermentation; I'll let you know how that change worked out. Actually I overshot the acidification to about pH5.0; will that have adverse affect on final beer, or nothing to worry about?

If I acidify sparge water to <pH6.0, should I still stop sparging at 1.010, i.e. is there still a risk with low final runnings gravity even if water is <78C and pH is <6.0? I'm just wondering how many things I need to change to crack this.

Thanks for comments.

 

[peebee]

You seem to be doing all you can with sparge water. pH6 is just a figure derived at as producing negligible leaching of tannins - initially over-alkaline sparge water is "buffered" to something more acidic by all the elements in the mash, hence SG1.010 is waved about as the lowest gravity to collect. SG1.010, pH6? I think you can view these "guideline" figures as one-or-the-other. High temperatures and high pH might leach tannins - hence there is no problem with the "decoction" mashing technique which actually boils part of the mash.

So other sources? Hops is one: Quantity, quality, left in contact for? Yeast can be responsible. Other sources … ? But don't mix up bitterness with astringency (common error).

I've had the problem once - finings (like isinglass) will help neutralise astringency (caused by tannin and the like).

 

[The Baron]

Are you using tap water for the boil and sparge and what volumes for mash and sparge?

 

[Fore]

You seem to be doing all you can with sparge water. pH6 is just a figure derived at as producing negligible leaching of tannins - initially over-alkaline sparge water is "buffered" to something more acidic by all the elements in the mash, hence SG1.010 is waved about as the lowest gravity to collect. SG1.010, pH6? I think you can view these "guideline" figures as one-or-the-other. High temperatures and high pH might leach tannins - hence there is no problem with the "decoction" mashing technique which actually boils part of the mash.

So other sources? Hops is one: Quantity, quality, left in contact for? Yeast can be responsible. Other sources … ? But don't mix up bitterness with astringency (common error).

I've had the problem once - finings (like isinglass) will help neutralise astringency (caused by tannin and the like).

Yes, I'm a bit stumped. I guess by trying all available parameters I'll eventually get there. The fewer beers ruined in the meantime, the better. I never went over 75C with my sparge so wondered how I ever got tannins. Anyway, the latest brew at pH5.0 sparge water will certainly give a pointer. I do use irish moss. I did (d0) wonder about confusing astringency with hops, but I woke up this morning with a grating feeling on my tongue; I'm pretty sure it's astringency. The beer is not "moreish".

 

[The Baron]

I had problems with grainyness astringency and cured it by using part RO water with tap water initially. I now mash with 14ltres of tap water(1/2 a campden tablet overnight) and 3 x 2 ltr bottles of Aldi water at 17p a bottle and it cured mine. I sparge with just tap water to my boil volume

 

[Fore]

Are you using tap water for the boil and sparge and what volumes for mash and sparge?

Hi. Treated tap water. Treatment is brew specific, normally gypsum, calcium chloride & acid to reach acceptable calcium level and achieve a pH of about 5.3 in the mash. I had a Murphy's water test so know my ions, and use Brun Water to give me a heads up on needed treatment quantities. I treat all the water, so normally the remaining sparge water is a bit too alkaline for the sparge, but last time (yet to be seen how it turns out), I tried adding acid to the sparge water to reach <pH6 sparge water. Water volumes used are as given (necessary) by Grainfather. Last brew was a 25l brew length, 5.33kg grain bill with 17.9l mash in and 16.4l sparge.

 

[The Baron]

I would try RO water for one brew and maybe try and make the sparge smaller and slightly increase the mash accordingly. Worth a try if you are at a loss. I got my RO from a local aquatic shop £2.50 for 25ltr

 

[Fore]

I've avoided RO water so far because my ion concentrations are in acceptable levels; I'd only be building back up to those same levels with added salts. Unless I'm missing something? But I did wonder about playing about with mash vs sparge volumes. Until recently I was a batch sparger, and there was a water to grist ratio of 2.5-2.8ish, and as I understood, this ratio was needed to ensure there were sufficient enzymes in contact with the grain. But how does this transfer over to the grainfather and continuous circulation? I'm thinking maybe you just end up with more wort at the side of the inner tube; you are not actually changing the water to grist ratio, or am I wrong? I think the calculator for the grainfather uses 2.7 in the calculation, which I took as the ratio. Anyway, worth a try moving a bit of the sparge water over to the mash.

 

[The Baron]

I use a similar system the Ace and mash with approx 4.5kg and 20ltr of water then jug sparge with 12 to 14 ltres of tap water at around the mash temp or slightly higher to my pre-boil volume of 28.5 approx and do not have any problems. I believe that over sparging can bring out extra tannins especially at the higher temps as you are aware maybe drop the sparge temp a little its going to be hard to nail exactly what it is

 

[peebee]

... I do use irish moss. I did (d0) wonder about confusing astringency with hops, but I woke up this morning with a grating feeling on my tongue; I'm pretty sure it's astringency. The beer is not "moreish".

Irish Moss is a totally different thing. Gelatine might have a similar effect, but I don't know for sure.

At this time of year if you have access to hedgerows, find a sloe and chew on that (careful of the stone in the middle but sloes ain't poisonous). I can't think of a better illustration of "astringency". Otherwise strong, stewed tea.

 

[The Baron]

Yeah astringency can be confused its like drinking a strong tea with no milk it will make the insides of your cheeks pucker and draw in also it can have a strong grainy texture and taste as well

 

[chthon]

It's fall and winter comes. Put them somewhere cool for a couple of months, the astringency will disappear naturally.

 

[peebee]

Yeah astringency can be confused its like drinking a strong tea with no milk …

… which I think is how the isinglass works in this case: the tannins (or other astringent polyphenols) bind to the proteins in the isinglass finings and sink to the bottom (like tannin in tea sticks to milk proteins - but I'm not sure I'd recommend adding milk to the beer).

A somewhat more "robust" description (than "your cheeks pucker") of the effect of astringency that I've come across (or was it just how my father described it?) is "it draws your ar** up to meet your mouth".

 

[Grizzly299]

Just a thought, but is the thermometer that you're using for your sparge water correct?

Try testing it using an Ice Bath to see if it reads 0 degrees C.

If you're changing a lot through your recipes and it's not making any difference I would be inclined to check your hardware.

Bittering with aroma hops could also potentially cause astringency too. As you're adding larger amounts of low alpha hops early in the boil to achieve your bittering you are naturally getting a lot more polyphenol extraction into you're wort.

Grain crushed too fine can give some astringency.Also some darker grains can leave an astringent mouthfeel particularly the dark Cara Malts and other roasted grains.

 

[Fore]

I just did a whole lot more learning on water treatment. I seem to revisit the subject every few months. This time it was actually a move to Brewer's Friend from Brun Water that helped my understanding along a lot. Although I started out with Brun Water, it seems Brewer's Friend is more intuitive; I like that you can lock in a target mash pH for example. Anyway, what I took from it is that I'm right on the limit with Chloride, and as I recently bought CRS acid (not a good move in hindsight, having previously used phosphoric), I'm limited with the amount of CRS I can add, as it pushes up chloride & sulphate levels. So I must stick to mash-only CRS and salt addition for now. So until I buy phosphoric acid to acidify my sparge water, my only course of action to prevent astringency is to reduce my sparge water temperature (I do also plan to move a bit of water over from sparge to mash).

I'll be buying phosphoric acid in 3 brews time or so. So my medium term plan is to use up my CRS in the mash, with a close eye on the ions thanks to Brewer's Friend, and acidify my sparge water with phosphoric acid. With a long term plan to again switch to phosphoric acid only.

So I now realise that the excessive sparge water acidification I did on my recent brew, with CRS, actually knocked my chloride & sulphate levels well above acceptable norms. So I probably shifted from one problem to another. Anyway, I'm hoping astringency is a lot more off putting in a beer than high chloride, so maybe "out of the fire into the frying pan"? I guess I'll find out soon enough.

 

[Grizzly299]

How much chloride are we talking PPM wise?

 

[Fore]

How much chloride are we talking PPM wise?

My tap water is 38ppm. Once I am through calcium addition to raise my calcium from 32ppm to 50ppm, I'm then at 50ppm chloride. Then after the CRS addition, mash only, I'm then at 86ppm. This is where I stand without any sparge water acidification. If I were then to acidify my sparge water, following the Brewer's Friend process, I'd then be at 125ppm chloride. Normally you are not supposed to be over 100 (sulphate at 194). What do you think; still OK to acidify?

In my recent brew I was using Brun Water which has no CRS option on the free version, so I was running blind. I actually added ONLY calcium chloride to ALL the water, no gypsum, then I decided to acidify my sparge water and overshot by a long way. So although I haven't bothered retrospectively punching in the numbers, I know it was well beyond the 125ppm of my next now well understood brew.

 

[rank_frank]

Hi Fore,

I wouldn't worry about having too much chloride from using CRS. Looking at my Murphy report it has desired chloride levels 150-250ppm for Bitter, 250-350ppm for Stouts and 0-200 for Lager.

You have almost the same chloride levels as I do (37 ppm) in your tap water. I have high alkalinity (250ppm) and I remove this with CRS in both mash and sparge water. I also use campden tablets to remove chlorine and don't add anything else. I also use a Grainfather like you and I don't get astringent beers.

Incidently, you can sparge with cold water if you're worried about the temperature extracting astringency. The mash conversion is over by the time you sparge and the only reason that you sparge at 75C normally is to end the mash conversion by denaturing the enzymes. With the Grainfather you don't need to worry about this as you've probably done a mash out holding the wort at 75C for 10 minutes as part of the mash. I'm not convinced that this step is necessary anyway as the wort is immediately being heated to boiling but since the Grainfather makes it very easy to do it then I do.

I treat and heat my sparge water to 82C in the Grainfather at the start of the brew day. I then put it in an uninsulated bucket sitting on the patio where I brew for over an hour whilst I heat the mash water and do the mash. By the time it's being used for sparging it's cooled quite a lot. I don't bother measuring it but it feels cooler than the mash temperature.

 

[Fore]

OK thanks. Good to know. I also have a Murphys report and saw those same "targets" which completely contradicted what Brun Water says and what I read others prefer to target. I didn't know which to trust. Ultimately, it was Murphys preference for DWB, with its predetermined and thus inflexible mix of salts, and reports of others, that finally had me believe Brun Water. But for me, your feedback on real life use means most.

I also have very high alkalinity (244 ppm), so we are in exactly the same boat. I feel a lot more confident to acidify my sparge water now then. Great. I guess my current fermenting beer, sparge water acidified to about pH5.0 will be the proof in the pudding.

I do mash out at 75C, but I was sparging at 75C mainly to keep efficiency high (I know there is a debate about whether that makes any difference). That said, my current efficiency is ridiculously high, with final runnings beyond 1.010, so little to lose by dropping the water temp a bit.

So I'll do both, acidify & lower temp, and see what it gives. I really understand a lot more about what is going on now than I did at my last brew, which was a wing it and see.

P.S. I also use a campden tablet. Why did you mention that; does it also influence ions?

 

[Grizzly299]

I really wouldn't worry about chloride being a problem until you exceed 300ppm and even then it will depend on how it's balanced out gypsum and the recipe in general. It can give a mouth coating cloying sort of feeling not all the disinilar from astringency.

For example if I was making a traditional golden bitter with a low ish FG I might have 200ppm chloride and 130 PPM sulphate to boost up the mouthfeel a little.

But for an ESB I might drop the chloride by 75-100ppm to offset the fact that I'm going to have a higher FG and a generally sweeter/fuller beer already.