lowering post boil pH

[aussie brewer]

Hi brewers, i just finished the boil of a german pilsner and the cooled wort pH is about 5.3. Should i lower it to about 5? i have lactic and phosphoric acids but not sure how much to use. Cheers!

 

[h22lude]

I lower my boil pH to 5.1 with 10 minutes left in the boil. Some fining agents work better at the lower pH.

 

[Vale71]

I'd say it's pretty pointless at this point ast he yeast will lower it to its final value in any case and 5.3 is already perfect for pitching.

 

[beersk]

I'd say it's pretty pointless at this point ast he yeast will lower it to its final value in any case and 5.3 is already perfect for pitching.

But lager yeasts do not lower the pH as much as ale yeast, hence the purpose of lowering the pH near the end of the boil on a lager. I always add 1-2mL of lactic acid at the end of the boil for light colored lagers.

 

[Vale71]

That will have little to no effect on final beer PH. Yeast is a complex biological agent that will tend to lower PH to its physiologically optimal level mostly cancelling out any minor differences in initial conditions.
By acidifying post-boil you won't get any of the positive effects of pre-boil acidification (better hot break, reduced wort darkening, milder bitterness) in any case.

 

[aussie brewer]

Thanks for the replies, i ended up adding 4ml of 96%phosphoric acid

 

[mabrungard]

Since a higher mash and wort pH (say 5.4) is desirable for DMS reduction when brewing beers with a high amount of Pils malt, the end of boil pH reduction (say 5.1 to 5.2) can be helpful for speeding the pH reduction created by the yeast and keeping your beer out of the grasp of spoiling organisms.

 

[aussie brewer]

Since a higher mash and wort pH (say 5.4) is desirable for DMS reduction when brewing beers with a high amount of Pils malt, the end of boil pH reduction (say 5.1 to 5.2) can be helpful for speeding the pH reduction created by the yeast and keeping your beer out of the grasp of spoiling organisms.

Thanks for the info mabrungard! i think i got it down to 5.1 with the phosphoric acid