Why Is Your Home Brew Beer So Bitter? Causes and Fixes

When making your home brew beer, there might be a lot of trial and error before the right flavor is obtained. The brewing process can be tedious in several ways. The common question is, why is your home brew beer so bitter?

Your home brew beer could be bitter from the pH being off, which can cause issues with enzymes, tannins, hop, and yeast. Another reason could be that oxygen was allowed into the fermentation process or the beer wasn’t stored properly. 

In this article, I will go into further detail on how the pH level can negatively affect essential components in brewing beer, such as enzymes, tannins, hop, and yeast, and why no oxygen is allowed into the fermentation process. 

1. The pH Level Is Too Low for Enzymes

When the overall pH goes below 4, this can affect the catalytic enzyme activity. If the pH drops lower than a 2, then enzymes can lose most if not all of their catalytic activity. 

Enzymes aid in the overall taste of the beer and also help the fermentation process along the way. 

Once this happens, the process can’t be undone or return to its original state before the pH dropped too low. The musk has been ruined. 

Different enzymes are involved in the beer brewing process. Consequently, the optimal pH range may vary slightly, but 5.2 – 5.6 levels generally work adequately. 

2. The pH Level is too High for Tannins and Hop

Tannins are a chemical compound that come from beer naturally. Having the correct amount of tannins is crucial to the beer’s flavor. 

The pH level affects the number of tannins. There is always a higher count of tannings when the Mash pH level is higher. So, in this case, the pH level shouldn’t get too high because an excessive amount of tannins affects the flavor. 

A pH level of 5.2 to 5.8 is the perfect range to have just the right amount of tannins to make a great-tasting brew. 

Having too much tannin will cause the beer to taste bitter and dry. This is called astringency. Tannins are great for beer and the flavor, but only when they’re in the right amount.

The same goes for the hop; this is the taste element mainly responsible for how bitter a beer tastes. The higher the mash pH, the more bitter a beer will become. However, the beer will completely lack flavor if it’s too low. 

Dried malt extract is used to sterilize the mash, and it also helps tannins and hop. However,  dried malt extract must be boiled before it is used, and here’s why:

3. You’ve Used Hard Water

One less talked about part of the brewing process is maintaining pH. Ideally your pH should hover in ranges optimal enough for yeast to work at maximum efficiency. 

Generally, your wort will generally be at the very least close to the optimum ph range for yeast. However, what happens when this doesn’t work?

First, the yeast will not ferment as well as it should, leaving you with excessively sweet beer. Of course this isn’t the problem here but I’ve brought up pH to shed light on one of the main things that affect it: Water hardness.

For many brewers —beginner’s especially— water hardness is not discussed nearly enough. While some water will affect the pH enough to cause sweet beer. It can also be a cause of bitterness.

Hard water can come heavily alkaline and once this gets into the beer it can give your beer a much darker taste than you accounted for. 

However, it’s important to note that water hardness in brewing can also be a benefit depending on what you’re aiming for. Hard water in particular can be good for texture as it gives the beer a richer feel. You might have to reduce your hops though to balance the bitterness.

That said, if this is the problem here, you’ll need an alternative to tap water as that’s the most common culprit of hard water. Rather, you can opt for store bought mineral or distilled water.

4. Oxygen Was Allowed Into the Fermentation Process

The fermentation process of a mash requires there to be no oxygen. Allowing oxygen in can cause oxidation which produces aldehydes instead of alcohols.

This alters the final flavor of the beer leaving it bitter and slightly sour. Although still drinkable, it’s a far cry from what you set out to achieve

To avoid this issue, the mash should never be stirred during fermentation. Stirring allows oxygen in and can also bring in bacteria which isn’t a good thing to add either. 

Once oxygen is added, there is no way to fix the problem. The entire batch has been ruined, so it’s best to start again with a different mash. 

Adding oxygen before the fermentation process does help to increase the amount of yeast suitable for the fermentation process. However, this must be a limited time and stop before fermentation begins to avoid messing up the mash.

5. The Beer Wasn’t Stored Properly

Beer can last for a very long time when it’s stored correctly. It can last for months or even years. If it isn’t stored correctly, it will go bad, and the flavor will be completely off. The spoiled beer can taste bitter or flat. 

Light is one of the main reasons the beer will go bad. Beer must be stored in a dark place like the fridge. No lights must be on in the fridge unless it’s opened for a short period, which isn’t enough to affect the beer negatively.

Beer needs to be stored upright to slow down the oxidation process. As we’ve discussed, oxidation isn’t beneficial to beer at certain stages. Keeping beer upright and not laying on provide some measure of protection.

Storing beer in the fridge is usually good enough temperature-wise. However, this won’t keep it fresh the longest. Knowing what different temperature types of beers need to be stored for optimal storage is essential.

Home Brew Advice has broken down the types of beers and the required temperatures: 

  • Lighter beers – store at 40℉ – 50℉ (4.44℃ – 10℃)
  • Mildly stronger beers – store at 50℉ – 55℉ (10℃ – 12.78℃)
  • Strong, burly beers – store at 55℉ – 60℉ (12.78℃ – 15.56 ℃)

The stronger a beer is, the warmer its temperature needs to be stored. Also, stronger and darker beers can be kept longer than light beers. 

Wheat beers and lagers can only be stored for 4 to 6 months, but sometimes six months is pushing it. 

Stouts, IPAS, Amber ales, bitters, and porters usually last about 6 to 9 months. 

Dark ales and high gravity beers can be stored for longer( 10 months to a year). These tend to get better the longer they have been in storage. 

Fixing the Home Brew Beer

Now that we’ve covered how the home brew beer can become bitter, let’s talk about how to fix these issues. Different things can be added to balance the mash’s ingredients and chemicals. 

Most of the time, different types of acids and salts are used. Acids lower the pH in the mash, but it depends on the type of beer being made and what kind of acid needs to be used. Salts can decrease or increase the pH of the mash as well. 

The different acids to fix the mash pH are as follows:

  • Phosphoric Acid. Phosphoric acid can decrease the water pH in a mash. It is a very safe option and is a common fix. Usually, it only takes a small amount of phosphoric acid to do the trick. 
  • Hydrochloric acid. Hydrochloric acid can be hazardous, especially when concentrated, so be careful when using it. This acid can decrease the pH but can cause the beer to be very salty if used in excess. Although you’ll only be using diluted acid, it’s still best to ensure no skin contact, so protective coverings are highly recommended.
  • Lactic Acid. Lactic acid is organic and not dangerous to use. A lot of it can be used to lower the pH of the mash. However, the beer can become sour and bitter if too much is used. 

Now that we’ve covered acids, let’s jump into salt and how different ones are used to help out the mash pH. Such as:

  • Calcium Carbonate. If the pH needs to be increased, then calcium carbonate is the way to go. 
  • Calcium Sulfate. This salt is used to lower the pH of the mash. A little calcium sulfate can be used to achieve a better pH level. 
  • Calcium Chloride. Using calcium chloride can also lower the pH level. 
  • Magnesium Sulfate. Magnesium sulfate, commonly known as Epsom salt, can be used to lower the pH level, but only in small increments. 
  • Sodium Bicarbonate: Baking soda or sodium bicarbonate can be used to raise the pH because it adds alkalinity. 

Now that we’ve gone over the types of salt used and what they do, let’s go over which salts can benefit the brew the most. Some types of salt go best with specific beers or fix issues within the brew.

  • Calcium Carbonate. This works best to decrease the pH level if the sulfate level is lower than it should be.
  • Calcium chloride. If the chloride level is low, this can be used to reduce the pH level.
  • Baking Soda. This is used to add alkalinity and increase the pH level.

It’s essential to pay attention to the needs of different beers. Making a home brew beer can almost feel like a science experiment with all the little details that go into making the perfect brew. The beer should turn out great as long as directions are followed and the pH is closely monitored. 

Why Your Mash pH is Important

When brewing beer, the mash is the mixture of ingredients before it becomes an alcoholic beverage. 

The pH of a mash is a crucial element in brewing beer. A wrong pH can affect the taste and body of the beer. 

Several things within the mash can be affected by the wrong pH level which is why I’ve explained in detail how each affects the overall taste and quality of the beer. 

First, let’s talk about your mash’s pH level. Generally, a pH of 5.2 is the goal. However, this can differ depending on the type of beer.

For malt beers, a 4.25 to a 4.6 is preferred, and for adjunct beers, a mash pH of 4.0 is better. Sour beers have a pH even lower than 4.0 at times. 

Mash pH starts in the broad range of 5.2 to 5.6, but the pH can decrease during fermentation. Ales will be in the 3.8 to 4.2 range and lagers in the 4.2 to 4.75 range.

The decrease of the pH level along the process is normal. However, if the starting pH is already lower than it should be, then this will cause quite a problem. The recommended ending pH level will be too low and negatively affect the beer.

This low pH can do several things to your home brew beer, such as :

  • Make the beer taste bitter and sour
  • Reduce the overall flavor 
  • Reduce the fullness of the beer

During the brewing process, multiple chemicals and ingredients play a part in the fermentation process, which leads to a good beer.

Conclusion

If your home brew beer is bitter, several things could be causing this. Mash pH is usually the main issue because it can affect essential elements in the mash, such as enzymes, yeast, tannins, and hop. 

Another issue could be that oxygen got into the mash during fermentation. No oxygen should be in the fermentation process as this ruins the batch entirely. 

Lastly, if beer isn’t stored correctly, the flavor can definitely become flat and bitter. Beer must be stored in a dark place, and the required temperature for storage depends on the type of beer.

About HomeBrewAdvice

Hello, my name is Simon. Together with a group of writers I write about brewing beer and making wine. We all share a passion for the great things in life, such as making stuff from scratch.

The business of HomeBrewAdvice is to bring you great information, stories and product reviews from brewing at home, and making wine


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