Bad Grinder, Bad Coffee

Once in a while, we receive complaints that our coffee has changed and now tastes bad. Since both Laura and I cup every roast for consistency and quality before we bag the beans, we know that it wasn’t the beans.
It is epidemic in our society to refuse to take blame. It is always someone else’s fault. If you rob a liquor store it is the owner’s fault for leaving cash in the till. If you lie to the FBI they should have warned you that it was a crime. If your internet goes down, it must be your router not the internet provider. So when customers complain we try not to be defensive. We know that customers don’t want to hear that it is not our fault. So we offer the best advice we can, offer a replacement or refund and move on. Often we believe the flavor problem is in their grinder.
Coffee lovers rarely think about their grinder. After all you drop the beans in the top and the grinds come out the bottom so everything must be OK. Sometimes it isn’t.

Use a Quality Grinder

In this age of throw away appliances the tendency is to buy cheap appliances and then toss them out when they break. However, quality coffee grinders are built to last. If you are buying high end specialty coffee one to two hundred dollars spread over several years for a grinder is well worth it. There are grinders on the market for several hundred dollars but they are designed for espresso grinds. A good quality conical burr grinder for drip coffee costs new between $100 and $200 dollars. Watch for used ones, we bought a Bodum at a thrift shop for $7 and a Baratza at a garage sale for $75.


A key to good brewing is consistent ground size. Regardless of what size grounds you want, they should all be the same size. Large grounds have less surface area than small grounds, so they extract more slowly. If you mix large grounds and small grounds, the small grounds will over extract and the large grounds will under extract. You will wind up with a mixture of bitter, acidic coffee and weak sour coffee.
The next time you grind coffee look at the grounds. Are they all about the same size? If not, you should clean the grinder and try again. If they are still not all the same size you may need to replace the burrs in the grinder. You can buy replacement burrs for quality grinders from the manufacturer. They aren’t hard to replace.
Dirty Grinder

Ground coffee builds up in grinders and gets old. If it breaks loose and falls into your daily grind it creates a bitter stale taste. Also coffee beans are oily. When coffee beans are ground the oils coat the inside of the grinder. Over time the oils get rancid, particularly if you don’t use the grinder every day. Rancid coffee oils will affect the flavor of your brewed coffee. If your coffee tastes rancid, fishy or burnt, check your grinder.
Sometimes fractured beans get stuck in the grinder where they get old. If they later drop into the grounds they will affect the taste of the brew.
Clean Your Grinder

Cleaning a grinder isn’t difficult. If you don’t have the manufacturer’s directions you can check YouTube where there are videos by coffee geeks showing you how to do it on your machine. Some geeks recommend grinding minute rice to clean your grinder, there are also grinder cleaners that you can run through your grinder. However, we recommend that you just follow these steps:1. Unplug the grinder.2. Take off the hopper and anything loose on top3. Take out the loose top burr.4. Turn the grinder upside down on a cloth and tap it gently to shake out bits and pieces5. Take a tooth brush (The free one the dentist gave you) and brush the top burr and everything in the grind chamber.6. Turn the grinder over and run the brush into the output hopper7. Put it back together, plug it in and run some beans through the grinder8. Check the grind consistency and size. Throw those grinds away. 9. Grind some good coffee.

Carry Over Flavors

When you grind coffee it leaves a residue in the grinder. Professionals always grind a few beans and throw the grounds away before grinding the rest of the beans. For example, a light roast coffee ground after a dark roast will taste darker than it should. The worst case is a light roast coffee in a grinder that had flavored coffee in it.You should always purge the grinder by grinding a few beans and throwing them away.

Foreign Matter

Things fall into grinders that you may not see. Leaving the grinder lid open is an invitation for insects looking for a dark place to hide. We had an employee leave a grinder open who ground a gecko into his morning coffee. It wasn’t pretty. If your coffee tastes off, make sure you didn’t grind something you didn’t want to drink.
We have also had employees drop metal into the grinder like screws and bolts. You will know quickly if that happens. If you are lucky and shut the grinder down fast, it will only cost a new set of burrs.Keep the lid on your grinder and make sure you are only putting coffee beans in the hopper.
Now that you have a clean grinder, take some great coffee, grind it, brew it and enjoy. You earned it.

Hula Daddy Kona Coffee LLC is a boutique farm in Kona, Hawaii that grows, processes and roasts its own current crop coffee beans. We grow 7 different varieties of coffee and process them using 4 different methods. We roast date every bag of our coffee.

Hula Daddy Kona Coffee is Coffee Review;s top coffee for 2108. In 2017, Hula Daddy Laura’s Reserve SL-28 received 97 points from Coffee Review and was Number 2 in the Top 30 Coffees of 2017.

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