When to Add Gypsum To Beer? (Simple Beer Salt Explanation)

Not all water tastes the same. I know hard to believe, I mean its water right? But, salts in water play a big role when it comes to flavor, not just in water but beer. One of the more interesting brewing salts is called gypsum and has gained a lot of popularity from the NEIPA trend.

Brewing salts like gypsum can be added during the boil, mash or post fermentation. Gypsum balances PH during the boil and mash, but post fermentation only has an affect on hop intensity to a lesser degree. Check with your local water authority for a water profile report before adding any salts.

I’ll be honest I live in an area with notoriously hard water so getting hop bite has never been a problem. But many brewers where the NEIPA originated might not have that same luxury so adding gypsum can solve that problem.

Making Beer with Added Salts Like Gypsum

Water Chemistry is far to complicated for me to explain here on this blog. Not that I would want to anyways since it will even make the most intense homebrewer fall asleep, me included.

But what I can say about brewing with salts is that it can be sort of simple if you look at it in terms of acidic or not acidic. Essentially measuring the PH level. You will want to add salt like Gypsum or Calcium Sulfate to make a beer more acidic or add Baking Soda or Sodium Bicarbonate to make the water less acidic.

You can also add chalk too, ya the same stuff you ate as a kid. So I guess that stuff really wasn’t that dangerous. If you want to look more into this check out howtobrew.

Why NEIPA Brewers Want To Add Gypsum

Beer Brewers in the Northeast United States have some softer water than other parts of the United States. The water can often lack acidity or hardness.

The best way to correct this is to add Gypsum, and the reason why they want to do this is because of the NEIPA beer style. New England IPA or Hazy IPA for short is a beer that is known for its fruity and floral hop flavor.

In order to make this more pronounced brewers will want to do everything they can to make the hops better and one of those ways is to make the water more acidic with Gypsum.

Tools for a NEIPA Water Profile

There isn’t really any standard water profile but there is a lot of anecdotal evidence that adding at least a tablespoon of gypsum to your IPA’s will result in a much better beer.

There are a lot of water calculators that you can utilize to give you a good idea of what you need to add or subtract to your base water.

Two examples are:

Personally I would just add a tablespoon or two to your next 5 gallon batch of IPA and if it makes a major difference in your mind then go all in on your water calculations.

How Water Acidity Affects Hop Crispness

When you are adding Gypsum you are making your beer or wort more acidic. This acidity will dry out the beer a bit and push the hop flavors forward on your tongue. This is also why you can add gypsum to beer after it has been fermented. For best results you will want to add gypsum to the boil.

Beer will naturally become more acidic as it ferments so the hop flavors will become more flavorful at that point. So its not just gypsum but a culmination of different variables that can affect your hop flavor. However, adding a teaspoon of gypsum post fermentation couldn’t hurt either.

Filtered Water vs Reverse Osmosis

I’ve heard some interesting things about adding salts into beer from both homebrewers and craft breweries alike and it really falls into two main camps.

  1. Filter your water and then brew.
  2. Reverse osmosis your water and add the entire salt profile.

The idea behind reverse osmosis is that you can build your perfect water profile for every specific beer. Which makes sense, and I’ve tried many breweries that do RO their water and add salts. Its very tasty to say the least, if not a bit more watery that filtered water.

By contrast when you filter your water you are keeping the main profile intact. Brewers that stand behind this method state that you really lose something unknown when you RO the water. There are many more compounds in non RO water that many realize and it adds uniqueness to the beer.

A Middle Ground with Augmenting Homebrew Water

Not much is known about what the middle ground is between these two dichotomies, I assume some breweries that use filtered water often augment their water with some salts.

I thought to myself why not take the middle ground and have the best of both worlds, add a bit of salt to my filtered water. At the very least I might be able to accentuate hop character without increasing the quantities of hops in my recipe.

Finding Your Water Profile Before Adding Salts

So how do you find your water profile?

Well in the United States at least its fairly simple. Just google your city or water company name and then type “water profile” right after it.

This should bring up at least a fairly recent report and from there you can gauge what your water profile is typically on any given day.

So how does this help us exactly? It can essentially let you know whether or not you have hard or softer water. Since I live in the United States in the Southwest my water is typically harder, so its already more acidic. You can tell that your water is harder by seeing if your dishwasher leaves significant water spots.

I probably won’t benefit too much from adding any more gypsum to my homebrew, but it still couldn’t hurt to add a few teaspoons to test.

Mash PH When Homebrewing

When you are doing an all grain brew mash PH is pretty important. So if you have not checked it at least once when brewing you want to check it out.

In order to check your mash PH you will need a PH meter.

After using the PH meter you can see whether you have a balanced PH. It should be somewhere around 5.2-5.6. If it’s higher than 5.6 you will want to add more gypsum to lower PH levels (a bit confusing, lower PH is more acidic).

You don’t want to add too much gypsum though, the side effect would be getting a bad rotten egg smell. This might be why your wife complains about your homebrew hobby. So if your PH is off you better make that right to keep from having a stinky house.

Brewing with Tapwater

I wrote an entire article on brewing with tap water but it essentially boils down to what you need to avoid. There are two main ingredients to tap water to help it from harboring pathogens. These ingredients are chlorine and fluorine.

You will want to get rid of these if you are going to have the best beer flavor possible. Although my friend brews with straight tap water and it comes out just fine, so don’t be too worried about it.

Learn More About Brewing Water

When it comes down to it the more flavor your beer has in it the less the water really matters. You can easily fix any water issues by just increasing the amount of hops or grain you have in your beer. This won’t help with more subtle beers though, like lager or pilsners.

Having said that if you really are brewing a lot and want to refine your beer and save a bit of cash in the process you could look to augment your brewing by messing around with salts.

If you want to get super technical when it comes to your brewing I suggest you pick up the Water Guide for Brewers.


Hey, I'm the the creator of frugalhomebrew.com. I have been brewing beer since 2013 and started by brewing in my parents home. I have written copy on numerous websites. Most notably Seeking Alpha, where I analyze small cap publicly traded companies. I have also written content for netnethunter.com and brokenleginvesting.com.

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