Homebrewing is an incredibly fun hobby, but it’s not without its frustrations. At some point, you are going to run into off-flavors in beer that you make yourself and you might be scratching your head as to what happened and how to fix it. One of the most common issues that brewers run into is that their homebrew beer is too sweet so I want to tackle this problem to help you prevent it from happening next time!
When homebrew beer is too sweet, it is almost always related to the recipe or using improper brewing techniques. Many common grains and other ingredients can lend extra sweetness to a beer naturally. Meanwhile, incorrect mash temperatures, a long boil time, or an incomplete or poor fermentation can prevent sugars from converting to alcohol properly, leaving residual sweetness.
My homebrews are far from perfect and I’ve struggled with this issue in the past. Let’s dive into the most common reasons why our homebrew would end up too sweet and see if we can diagnose the culprit in your beer!
When the recipe makes homebrew beer too sweet
Brew day starts with the recipe, and one way to prevent extra sweetness is to make sure it never goes in the pot!
The three most important aspects of the recipe that you’ll want to control for are:
- The grains, malts, extracts, and other additions that you make that will produce fermentable sugars inside the wort.
- Any unfermentable sugars added either during the brewing process or at the very end that will simply carry through to the finished product.
- The attenuation profile of your yeast.
Let’s see what these look like!
1. Some grains make your homebrew beer sweeter than others
When it comes to grains, each and every one of them is going to act a little differently when making homebrew beer and some provide more sugar than others. If your beer is extra sweet, check the recipe for:
- Pale malt – Pale malts are made from steeped and germinated barley grains. They are the lightest and sweetest of the ‘base malts’ and will, therefore, be a little sweeter than something like a Munich, Vienna, pale ale, or even a pilsner malt.
- Crystal or Caramel malt – These are basic specialty malts that are typically added to a recipe specifically to add sweetness. Just like the pale malts, they are made by steeping and germinating barley grains. For crystal malts, however, this is followed up by two additional steps: steeping and kilning. Steeping keeps moisture inside the system and produces extra sugars from starch inside the grain. While the grains dry in the kiln, they will turn darker and some of the sugars will carmelize from the heat. Many of these sugars are unfermentable and carried through to the final flavor profile.
- Any other cara- malt – If you see a malted grain that starts with the ‘cara-‘ prefix then it’s probably going to be a sweeter, specialty grain added to base grains in a recipe. There are tons of examples of these such as the Carabrown from Briess or the CaraAmber from Wayermann.
All other things being equal, lowering or substituting these base and specialty malts in your recipe will help lower the sweetness a little. Just be sure you aren’t changing the recipe so much that you are changing the whole profile of the beer though!
2. Using additions such as lactose or other unfermentable sugars
It’s common for many homebrew recipes to include unfermentable sugars on purpose to improve the body of the beer or otherwise change its mouthfeel. Because these sugars won’t be broken down during the fermentation process, they will make their way into the final product so having too much of them can make homebrew beer too sweet.
Check your recipe for the following:
- Lactose – Used for sweetening homebrew. Commonly found in beers such as milk stouts.
- Dextrin – Usually found in malted grain form and adds sweetness to beer.
- Maltodextrin – Only 3% fermentable by typical brewer’s yeast. This sugar occurs naturally during the homebrewing process regardless of the recipe, but adding extra will add sweetness to the final product.
3. Check your yeast strain’s attenuation and flocculation profiles
There are a ton of variables to consider when it comes to yeast that will dramatically affect the flavor profile of your beer, but for the purposes diagnosing why our homebrew beer is too sweet, we will be looking at the attenuation and flocculation properties of the yeast you are using in your recipe.
Yeast attenuation is essentially the percentage of malted sugars that a particular strain of yeast will convert during the fermentation process and strains are usually rated low, medium, or high according to this scale:
- Low – About 65-70%
- Medium – 71-75%
- High – 76-80%
All of these ratings are based on the ‘apparent’ attenuation of the yeast which is basically what is measured after comparing the original and final gravities of the beer. All other things being equal, a yeast with higher attenuation will process out more of the sugar in the wort, leaving a dryer beer.
Yeast flocculation is essentially how the yeast behaves during and after the fermentation process. High flocculation means that more yeast will clump together and drop out of the beer, collecting on the bottom of the fermenter (English/London ales). Low flocculation means that more of the yeast will remain floating in the beer, making it cloudy or yeasty (Hefeweizens).
With regards to sweetness, a yeast that flocculates too early could leave a beer under attenuated because they stop doing their job before all of the sugar is processed from the wort.
4. You may simply need to add more hops to the recipe
This one might seem obvious, but I wanted to bring it up last in the recipe section because we don’t want to just add hops to a brew to cover up other issues. Of course, the issue could also be that you don’t have enough hops in the recipe to make the beer true to style or perhaps the hops were entered at the wrong time.
Hops provide bitterness to a beer which can help offset any natural sweetness leftover from the ingredients mix and contribution of flavor from the yeast. If you are using the correct amount of hops for your recipe, ensure that you are putting them in at the right time – they add the most bitterness if you add them at the beginning of the boil.
For those of you kegging that ended up with a beer you find too sweet, there is also the option of dry hopping with extra hops to bring more flavor and bitterness to your homebrew.
When using an improper technique or making mistakes makes your homebrew beer too sweet
Assuming that you have your recipe dialed in and you know what your beer is SUPPOSED to taste like, too much sweetness in the brew is likely due to a technical error on your part during the brew day. Unfortunately, it’s too late to fix these for the beer you have already finished, but you’ll be able to keep these in mind for next time.
The three most important techniques you want to control are:
- A high-quality and properly complete fermentation
- Correct mash temperatures (if you are doing all-grain or partial-grain)
- A boil time that isn’t too long
Let’s check these out one by one!
5. Make sure your fermentation is actually finished
Fermentation gets a lot of new brewers into trouble because there are so many variables at play. Between cooling the wort, pitching the yeast, setting up the airlock, controlling temperatures, and playing the waiting game, there is a lot to get right!
If your beer is too sweet, then the most likely fermentation-related culprit is that you simply didn’t let it finish. This could be because you simply bottled or kegged too early while the yeast was still active or that your fermentation got stuck and looked like it was finished, causing you to pull it early.
To ensure that your fermentation is actually done make sure that you:
- Measure the specific gravity rating after your brewing is done (original gravity) and see how it compares to the recipe. If your number is way off there may have been a problem during brewing.
- Let the fermentation run its course for at least 7-14 days.
- Airlock activity should have stopped and you should see no visible signs of active fermentation (frothing, bubbling, etc.)
- Check the specific gravity after you think the fermentation is done (final gravity) and see how it compares to the expected finish in the recipe. It should be exactly the same or at least darn close to the recipe. If it’s higher, fermentation probably isn’t done yet.
- The final gravity should stay at the expected final gravity reading for at least three days in a row.
Note: If your fermentation seems to be stopped, but your final gravity readings are way too high, then you might have a stuck fermentation. I’ll soon have a guide on how to fix this issue, but it’s probably related to poor yeast quantity, quality or nutrition. It could also be too cold in your fermentation area.
6. Check your mash temperatures
During the mashing process, the hot water converts starches in the grains into sugars that we’ll need to ferment into alcohol for the finished beer. Typically, mash water temperatures range from about 148-160 degrees Fahrenheit.
In general, using water at the extreme higher end of that water temperature range or even above it will still create a lot of sugar from the grains, but more of them will come out as unfermentable sugars because of how the different enzymes operate during the mashing process. These extra sugars will survive through the fermentation process and cause a higher final gravity and, therefore, a sweeter beer. It can also cause more bitterness-causing tannins to form in the flavor profile.
Here’s what you need to watch out for when it comes to proper mash temperatures:
- Check the correct water temperature for your mash in either the recipe or brewing software that you are using. Both should anticipate a DROP in the temperature in your strike water once you add the grains into the mix, settling to the correct temperature. In general, you lose about 1 degree per pound of room temperature grain.
- Be sure that you are mixing up your strike water and then your mash tun to get an accurate reading on your thermometer.
- If your temperature isn’t correct after adding grains, you can add cold or hot water to make small adjustments to get it in range.
7. Adjust your total boil time
All other things being equal, a longer or super intense boil can cause reactions inside the wort that can lead to extra sweetness in your homebrew, but this is a relatively minor concern. Mainly, longer and more intense boils will likely produce more browning reactions (or Maillard reactions) and caramelization. These reactions are actually planned for and desired result in many recipes, but overboiling could cause them to go overboard.
- Browning reactions create melanoidins which can lend malty, toffy, nutty, and biscuity flavors to a beer’s flavor. Some of these can be interpreted as sweetness by the mouth.
- Caramelization is pretty straight forward. If some of the sugars are caramelized then they will stay through to the final beer and add extra sweetness to the flavor.
Will sweetness condition out of homebrew over time?
Unfortunately, the sweetness is not something that will likely be reduced over time as homebrew is conditioned in either a keg or bottles. Since reducing the sugar content requires active fermentation, it’s unlikely that you’ll have enough activity inside the bottle to do much good.
Something to point out is that if your homebrew tasted fine before bottling, but then tasted sweet after bottling, then you probably added too much priming sugar or there somehow wasn’t enough yeast left in the brew to remove all of the priming sugar. If this is the problem, then you’ll probably notice a lack of carbonation as well.