Adjusting the mash ph in flight

[HantsGaz]

Hi All,

Are there any rough rule of thumbs to work out how to reduce a mash ph? I've just put a mash on and the reading I'm getting from my papers is >5.5 so I was wondering when it comes to next time - what extra mineral salts to add, or if you can adjust in flight. My liquor started out as Tesco Ashbeck mineral water:

Calcium: 10
Magnesium: 2.2
Sodium: 10
Sulphate: 11
Chloride: 15
Bicarbonate: (HC03) 13
[Calculated Carbonate: (CO3) 6.39]

And then I adjusted it to meet the General profile in Graham's water Calculator. My grist is 4.5kg of Pale Malt and I've mashed at a ratio of 2.5.

Any ideas?

Thanks, Gaz.

[HantsGaz]

Thanks Chris - will give that a go next time (I always aim to add a tsp of gypsum to the boil - well, when I remember to!).

[HantsGaz]

So, would your advice be to keep adding add a tsp of gypsum to the mash (and checking the ph each time) until I get into the right range?

As an aside - Goose Island don’t really bother about any kind of water treatment for their beers (I found this out on a recent visit). All they do is boil the water, regardless of style, and only when they taste the end product do they decide to adjust the water profile next time around if they feel it’s a bit thin or dry etc. I specifically asked the brewer about what water treatments they use and how they get the mash ph to the right range and the answer was pretty much "we don't check or bother that much – we boil and that’s it"! That surprised me.