My Top 4 Most Common Homebrewing Mistakes

1. Temperature Targets

Strikewater, Mashing, Fermentation

Temperature is probably my most common mistake, but I seemed to have worked through it nicely. There’s a lot different information to find out there, and a lot of it conflicts.

Calculating the temperature you need for strikewater is going to depend on the amount of grain you’re using, the type of mash tun you are using, and the ambient temperature. On a mild day, using my Igloo water cooler, with 8-10 pounds of grain, I usually estimate that I need about 10°F higher temp than what I should mash at. If I need 152° I’ll head the strikewater to 162°. That’s assuming that I’ve already preheated the mash tun with a gallon of hot water before actually starting the mash.

The first time I forgot to do this was with my pumpkin rye, and I saw a temp drop of about 15° after adding the grain and strikewater to my mash tun. I ended up about 3 degrees lower than my target mash temp, so mashed at 148°-149° instead of 151°-153°.

Mashing temp is also a mistake I make routinely, getting too high or too low. Apparently there is a range at which you can mash and not ‘mess up’ your beer, but it may change the character. When I made my Irish red I read that a higher mash temp will produce a drier beer, and a lower one will produce a sweeter one. I opted for a higher temp, and like the results (obviously), but have not compared so I can’t confirm how much of a difference this creates.

Fermenting temperature is the most difficult to maintain because I do not have a dedicated fridge or room for fermenting! I also live in Southern California where it’s hot year round, and you can probably guess that it’s hot in summer.

I have a broken freezer that I use like an old-school ice box, replacing gallon jugs of ice 1-2 times each day to try and maintain the proper fermenting temp. Life gets in the way, I forget, add too much or too little ice, and I end up with a range of about 5-10 degrees. So far, I haven’t noticed any ill effects, but it definitely does make it difficult to measure my results and draw conclusions.

Note: I’m sure the beer doesn’t change temp so quickly, considering it’s 5 gallons of liquid, but I just don’t know how the liquid temp compares to the ambient temp.

2. Wort Volume (Gravity)

Now this homebrewing mistake definitely does affect the character of a beer, and in an obvious way. Once I forgot to throw out the water I used to warm the mash tun and ended up with about 7.5 gallons of runoff instead of 6. With that much wort, I was sure to have too much water and not enough sugar from the malt, which would make my original gravity too low. That would result in a weak, low alcohol, less flavorful beer.

When I brewed my chocolate bock I thought 6 gallons of runoff was plenty, and threw out about a gallon of extra wort, thinking I wasn’t going to need it. I ended up with about 4.5 gallons of beer instead of the required 5, resulting in a higher original gravity than expected. This means that the sugar/water ratio is higher than you want.

You can fix a low gravity wort by having a longer boil. Basically you are looking to boil off excess water, and bring down the final volume to whatever your target is. It should be easier to hit your targets this way.

If you have less volume than needed, check your gravity first! If your original gravity is on target, then do nothing. You will have less beer, but it will taste like it’s supposed to. If your gravity is too high, you may have boiled it for too long and have too many sugars. You can add some water (boiled, then cooled to sanitize it) and bring your original gravity to your target.

3. Pitching Rate, Yeast Health

This is a new one for me. I never thought much about yeast, but the more I brew, and talk to other brewers, the more I’m finding out that the type, amount, and health of your yeast is super important.

The first beer I made was with dry yeast. I just dumped the packet in. Then I thought I was hot stuff working with liquid yeast, and again, just dumped the vial in. I then “went pro”, and started making yeast starters. But then I made a bock, and learn that lager yeast starters are different, so I bought big Erlenmeyer flask to make a double batch of starter. I just discovered during the brewing of my orange clove witbier today (link coming soon) that for a 5 gallon batch, my starter should be at least 1 liter. That’s about 5 times larger than what I had made, so we are talking 1 liter of water and 2 cups DME instead of the 2 cups water and 1/2 cup DME that I had this time.

Wait, what? So why did the  brew store sell me a 500 ml flask for my starter (the first one, on my Pumpkin Rye). I’ve also just discovered this yeast pitching calculator. So yeah, I’ve still got a lot of work to do.

More Yeast Problems: Pitching Temp

I know 100% that I am not the only homebrewer with this issue. The issue at hand is not exactly that the wort is cooled too slowly – that in itself will not affect your beer at all, so long as you don’t get any bacteria, wild yeast, or other things blowing into it during the cooling process. Sanitation at this point is key, but the time you take to cool the wort is not vital.

What is important however, is the yeast pitching temperature! You are taking 200°+ temp and trying to pitch your yeast somewhere between 60° and 70°! Taking it down from 200 to about 80 or 90 is not an issue, but for people that live in warm climates, and for those with less than adequate wort chillers, those last 10-20 degrees take an extraordinary amount of patience.

Pitching at too high of a temperature can either kill your yeast, or shock them from the high temperature. For ales, you’ll be fermenting at around 65°, and for lagers at around 50°, and you want to pitch as close to those temps as possible

I’ve pitched at as high as 78° and not had a big problem, but with a not-so-refined palate, I might not have detected those off flavors. I have a friend that doesn’t mind pitching at 80°, and she says it’s never been a problem. But I’m particular about these things, and I’ve always tried to get the temp as low as possible.

Pitching a lager yeast at 55° is next to impossible on the same day unless you have a seriously effective way to cool your wort. I simply cooled it to about 75°, put the carboy in the ice box, and let it sit overnight to bring down the temp. There’s nothing wrong with that, just make sure you are careful about sanitation procedures to keep your yeast and wort free from harmful bacteria! You might be giving them a head start by not introducing yeast early enough into your beer!

4. Bottling Errors

I don’t know why I have so much trouble with bottling. Maybe I should keg instead. I’ve heard time and time again that a bottling wand is the perfect size for filling. Just stick it in the bottle, fill it to the top, and when you pull out the want, the bottle will have the perfect amount of head space. I disagree.

I know that about an inch is the way to go, and using the method described above, I see about 2 inches. That might not be a big deal, but I know that too much head space can cause oxidation and carbonation problems. So I always have to go back in and top off the bottles, which probably adds risk of oxidation anyway.

Speaking of oxidation, you are also supposed to be super careful not to disturb the beer too much, because swishing it around can introduce oxygen and a chance of off flavors to your (so close to being done) beer. It would be horrible to work so hard, only to screw up the last step!

But somehow there’s always some kind of problem with siphoning that causes bubbles and improper filling procedure. Again, I might just be too much of a perfectionist or worry-wart, because so far I haven’t noticed any real effect on the final beer product.

These are my most common homebrewing mistakes. Nothing too big, but they are things that can definitely affect the final product. It’s definitely not a good idea to stress about these minor issues, because is the end, we are trying to make beer we like to drink, not just hit temp and gravity targets!

But in the same breath, there’s no reason to keep making the same mistakes over and over again. I will continue to brew, and try to improve my craft.

Think about your own brewing process. What are your most common mistakes?



About Nate

I created this website almost two years ago when I first started homebrewing. Like my brewing, it's been through many changes over the years.

I'm a full time online marketer and brewing beer is my hobby. You'll find a mix of all topics related to craft beer and homebrewing at xBREWx!

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