Moving to BIAB and have pH Questions

[Bassman2003]

Hello,

I am moving to BIAB after batch sparging for about 10 years. I will be doing a full mash volume without sparging and am cautious about the Bru'n Water pH adjustments I am getting.

With my old setup I typically use about 5.25 gallons in the mash and 5.25 for the sparge. Grain bill is usally around 10-11 pounds. With the boil off and my efficiency this would yield about 5.5 gallons of 1.050 - 1.055 wort.

For lighter beers I would add 4 - 8 ounces of Acid malt to the mash along with 1/2 tspn of CaCl. I would also add .35 ml of lactic acid to my sparge water. 2 gallons of RO water are used to dilute my mash water as well.

When I adjust this recipe for BIAB I wind up with a 1 pound addition of Acid malt to reach a pH of 5.4 This makes sense as I am losing the .35 ml of lactic acid and the water ratio is different but it just seems like a lot of acid malt.

Does this sound right? Thanks for your input.

 

[PlinyTheMiddleAged]

Bassman2003,

That is a LOT of acid malt. If I recall correctly, the general advice is to keep the acid malt additions to a few percent (3 ish?) to keep the lactic acid under the taste threshold.

Are you working with tap water with high alkalinity? If so, you might want to see what diluting your source water with RO or distilled will get you. You'll need a lot less acid to knock down the alkalinity if that is your issue.

Cheers!

 

[Bassman2003]

Thanks for your reply. Yes, it seems like a lot of Acid malt!

I have attached my city water report as well as two screens from Bru'n Water.

Thanks for your help!

 

[BigRob]

I end up using about 6ml Lactic for a 32L BIAB full volume mash (23L fermenter). A full pound of acid malt seems pretty high, especially if you're already diluting with RO. Also those volumes seem off. Even without squeezing I only get losses of about 1L per KG of grain (1pt per lb).

 

[Bassman2003]

Thanks for your reply. About the water volumes... I have been brewing for 10 years and these are the water volumes and grain amounts I have to use for my system. I seem to get a large amount of boil off with my kettle. I boil with a 4500w element. Maybe I had below average efficiency but these are the numbers. 5 gallons in the mash and 5 gallons of sparge water.

Since this is my 1st BIAB, I am going to go with 10 gallons in the mash and see how the gravity works out then adjust.

 

[Bassman2003]

o.k. I have paid more attention to my water report numbers and added 2 more 1/4 teaspoons of CaCl to the mash. I can now get a mash pH of 5.4 with using 12 ounces of acid malt (6.7 %) in my 10.5 gallons of water.

If I use lactic acid this is equal to a 7ml addition. Sound like it is more on target?

 

[PlinyTheMiddleAged]

Bassman,

Have you looked at how your numbers change if you either 1) dilute with more RO, or 2) mash with less than full volume?

I still think that Bru'nWater is calling for a lot of acid and that the amount of acid will lead to flavor issues with the brewed beer, but perhaps I'm wrong about that.

Frankly, your water does not seem that bad. I just think that with a light grain bill and a lot of water, you are asking for a lot of additional acid to move your pH.

If you increased you mash thickness, the grain can work better against the relatively smaller amount of alkalinity. But then you have a sparge step to deal with. Some folks decry sparging with BIAB as blasphemy. Whatever. As long as you're making beer and your chosen process works for you.

The other option is to go full volume as you have planned but to dilute further with RO. I'd increase the dilution percentage until the level of acidulated malt is closer to 3% of the grain bill.

Cheers!

 

[orangemen5]

Your water is almost identical to mine and I dilute 50-50 with distilled for lighter beers. I don't have to use much acid malt if any. The gypsum and calcium chloride I add to get the sulfates and chloride levels I want puts the mash ph right where it needs to be with a little adjusting. I think you just need to dilute with more RO. It will cutdown on the amount of acid malt you use and the flavor it will add.

 

[ajdelange]

Putting your numbers into a spreadsheet we see that to overcome 88 ppm alkalinity to pH 5.5 would, assuming that you are mashing with 1.3 qts water per lb of grain, require 20 mEq of acid. You can get that from 2.5 Oz sauermalz or 1.8 mL 88% lactic acid. Now you still need about the same amount additional acid to get your grains to pH 5.5 so that's another 2.5 oz sauermalz or another 2 ml of the acid. Total, for pH 5.5 should be about 3.2 mL of the acid or 4.5 Oz of sauermalz. Thats just under 3% sauermalz so you should be OK on the taste aspect. These are approximate numbers as sauermalz may vary in its acid content.

Now if you wanted mash pH of 5.4 you would need 4.3% sauermalz (7.5 Oz). Probably still OK taste wise.

 

[Bassman2003]

Thanks for your replies. I have diluted with more RO water in the past but found the beer was a bit thinner to my taste buds. I guess I like the character my area water brings to the beers. So I am at a crossroads.

I do not really know the taste threshold of Acid malt. but I do like a little bit of tartness in my hefeweizens, so I will go ahead with 11 oz and see how it goes.

I have always put 3.5ml of lactic acid in my 5 gallons of sparge water as well as treating the mash, so my total acid amount is not that far off with the BIAB setup.

AJ, I will be mashing full volume BIAB so my water to grain ratio is more like .97 from Beersmith.

 

[Yooper]

AJ, I will be mashing full volume BIAB so my water to grain ratio is more like .97 from Beersmith.

Full volume mashing with that water means that the pH will be high, as you know. Diluting it with RO water will not "thin" the beer, but instead get your pH into range without adding acid that may have a flavor impact.

BIAB is awesome for many people, but the full volume mash means that in highly alkaline waters, the pH will be higher than desired. Adding acid works, but you definitely want to stay below the flavor threshold. Diluting with distilled or RO water will get you there.

 

[orangemen5]

Your beer might have seemed thin when you diluted because your diluting the ion concentration with it. Your chloride and sulfate levels are too low in your existing water to begin with. You should be adding salt to the brew kettle to bring it to your desired flavor profile. Whether your diluting or not.

 

[Bassman2003]

Good points and I will take a look at my mineral adjustments going forward. This is my first brew with BIAB and I have some things to adjust to. I am hoping I will enjoy it and get great results but know process takes a bit of time to dial in.

I am going with 11 oz of acid malt for this beer and it will be interesting to see if I can taste any tartness. It will be fine if it does since it is a hefeweizen. My guess is that I will not notice anything but this is homebrewing and the science side is fun too.

Thanks for your input!

 

[Bassman2003]

Your beer might have seemed thin when you diluted because your diluting the ion concentration with it. Your chloride and sulfate levels are too low in your existing water to begin with. You should be adding salt to the brew kettle to bring it to your desired flavor profile. Whether your diluting or not.

Orangeman, what minerals/salts do you think I should add to my water?

Thanks

 

[orangemen5]

Calcium chloride (gypsum) to up the sulfates for a pale ale and ipa. Calcium chloride for maltier styles. You can match your sulfate and chloride levels to bru n waters existing water profiles. It will tell you how many grams u need to bit your levels also. Some ppl like their sulfate levels close to 300 others 200-250. You just need to brew it with different levels and see what your taste buds like. Good luck.

 

[jbaysurfer]

I think Orangmen meant to say Calcium Sulfate (Gypsum) in that first line. Looking at your H20 Profile, you have plenty of Chloride fwiw.

 

[orangemen5]

Yep calcium sulfate. Sorry for the confusion.

 

[Yooper]

Keep the chloride under 100 ppm in all cases, and many people like the sulfate level (even in IPAs) restrained as well. Depending on what you're making, "less is more" is generally the best approach. Chloride of 50 ppm or so is a great basic level. Since you're making a hefeweizen, the appropiate amount of sulfate (calcium sulfate, via gypsum) to add is 0.

Target the correct mash pH, and the flavor ions will be fine as long as you keep them restrained.

 

[Bassman2003]

Yep. I only add Gypsum for Pale ales. I setup my bag winch today. Hopefully all will go as planned with BIAB brewing.

 

[Bassman2003]

Update:

Brewing the hefe right now. I hit my gravity volume numbers right on target. Seems my previous mash tun was about the same efficiency. So all went well. Although I am posting about sediment on the BIAB forum as there was a bit more in the kettle than I expected.

 

[dfhar]

I brew BIAB but I don't do a full volume mash. I typically mash at 2 quarts per pound, and once my mash is done I top off with enough water to reach my target pre boil gravity. Then, I pull and squeeze the bag and boil away.