Epsom Salts

[ronniedeb]

Do I need a specific "food grade" Epsom Salts, or will your regular chemist Epsom Salts be OK for brewing? The Homebrew ones look a little expensive in comparison.

[DEMPSEY]

Epsom salts is Epsom salts ,buy the big box in the chemist and after spending along day on your feet brewing sit back with a pint in your hand and your feet in a basin of warm water with Epsom salts in it

[Tom]

Epsom salts are Magnesium Sulphate, so I wouldn't go mad with it. Except in the bath. Make merry there!

[Leann ull]

Like all minerals or salts there are refined food grades and so no not all are suitable for human consumption, when you walk into the chemist be explicit in advising what the intended use is to ensure you get it in its purest form and not just the product to soak aching limbs with.

As Tom says use sparingly its primary use in medicine is as a laxative.   

[Dr Jacoby]

Not sure what you want to use the magnesium for but just in case it helps:

- Malt contains enough magnesium sulphate for most beer styles
- magnesium sulphate is about half as effective at lowering pH as calcium sulphate (or calcium chloride)

Food for thought

[BrewDorg]

Would it make sense to use epsom salts if you wanted to boost sulfates without also boosting calcium? My water appears to be rich in calcium so when I plug the details into the water calculators, my calcium levels shoot way too high when I use only gypsum or calcium chloride to adjust. I used a combination of lactic acid, epsom salts and gypsum to adjust the mash pH in my last brew.

[Dr Jacoby]

Would it make sense to use epsom salts if you wanted to boost sulfates without also boosting calcium? My water appears to be rich in calcium so when I plug the details into the water calculators, my calcium levels shoot way too high when I use only gypsum or calcium chloride to adjust. I used a combination of lactic acid, epsom salts and gypsum to adjust the mash pH in my last brew.

Can you give me some more info on your water profile? It's hard to offer any advice without seeing the detail.

[BrewDorg]

This is the average values for 2 years on a public system.

Alkalinity CaCO3 - 150 mg/l
Bicarbonate HCO3 - 183 mg/l
Calcium - 70 mg/l
Chloride - 20 mg/l
Magnesium - 6 mg/l
pH Level - Min(6.6) Avg(7.3) Max(8.1)
Sodium - 9 mg/l
Sulfate - 25 mg/l

I used the EZ water calculator to adjust to my desired profile. I paid particular attention to the Chloride / Sulfate ratio after reading the impact it can have for bringing out malt or hop character in diffeent styles.

[Dr Jacoby]

Thanks, great to have some figures to work with. Ok, just for context, it's fine to add up to 150ppm of calcium to medium bitter beers and up to 300 or 400 for very bitter beers. The issue is not really how much calcium you add but what salt you use to add it.

Looking at your numbers you are pretty low on calcium sulphate  and chloride. What you are high on is bicarbonate (and alkalinity).

Ok, I'm assuming that since you want to boost your sulphate levels you're looking to brew a hoppy beer? If so, I'd suggest trying to cut your bicarbonate level right down to produce a softer water. That way you'll be starting from a solid base and can add calcium sulphate with a clean conscience.

Here are the main options for reducing bicarbonate:

1. Dilute your water with RO/distilled/very soft water.
2. Use acids to counteract the alkalinity - e.g. lactic, phosphoric or CRS
3. Boil and decant your water to remove temporary hardness (bicarbonate) - this will reduce your bicarbonate level to about 60pmm in practice

I recommend option one if you can source the softer waters cheaply. Tesco's Ashbeck water is very soft and relatively cheap.

If you're brewing a darker beer with roast malts you may not need to do anything to the water at all (except get rid of chlorine which is always best practice).

[BrewDorg]

Good info, thanks a lot. If there was a Tesco nearby I'd definitely used that water, but I've gone with option 2 for reducing alkalinity. Adding ~5ml of 80% lactic acid to my 20L of water.

And you're correct, the high sulfate water profile I'm planning on now is for a hoppy pale ale. Conversely, what would you recommend for a malt-forward beer?

For chlorine and chloramines, I use a half campden tablet. As a test, I've added campden tablet dust into some drinking water and the difference in taste is crazy. I've yet to bottle a batch I've used campden with but I can see it having a massive effect.

[Dr Jacoby]

If you want to use acids to control mash pH (a good idea), I'd not worry about adding either calcium sulphate or chloride to the mash. Instead, consider adding them as appropriate to the boil. For hop forward beers use sulphate, for malt forward beers use chloride. Just keep an eye on the overall levels to make sure you're not overloading the beer with minerals. Less is more.

Personally, I prefer a rounder malt and hop profile so I tend to use chloride in most situations myself. For German pilsners and other very crisp styles sulphate can help.

Campden tablets are great. Thank _god there's such an easy option available to us.