The Great Coffee Experiment

How one woman's coffee turned into a full-blown investigation that nobody asked for.

It All Started With a Red Keurig

I've been using single-cup coffee makers since 2011. My first Keurig was red. Put a K-Cup in, push a button, and out comes coffee. Pretty straightforward. For years, that's how I made my morning coffee. I wasn't a coffee expert, and I certainly wasn't grinding my own beans. I just wanted a good cup of coffee without making an entire pot, and I thought I was doing pretty well.

Then Kristie came along. Now, Kristie makes some absolutely amazing coffee, and she knows it. Matter of fact, she openly jokes that I'll never make coffee as good as hers. Not because of the coffee maker or the beans, but because she's the one making it. You know, there's not a whole lot you can say to that, but apparently, I took it as a challenge.

The Twelve-Dollar Coffee Maker

Before the real investigation started, there was Rocklahoma. Kristie and I went for four days, and we needed coffee at our campsite, so we bought a little twelve-dollar coffee maker. Nothing fancy, just something cheap to get us through the trip. And you know what? That twelve-dollar coffee maker made better coffee than my hundred-dollar Keurig. Now explain that to me.

I've spent plenty of money on equipment over the years, and I'm not somebody who believes the most expensive thing is automatically the best. But you'd think a hundred-dollar coffee maker could at least outperform something we bought to use at a campsite. Apparently not. We enjoyed our coffee and went on with the trip, but that experience stuck with me. Back home, I still had a coffee maker I wasn't particularly happy with, and I wanted the kind of coffee Kristie was making.

Finding Kristie's Coffee Maker

I started looking at other Keurig machines and even asked ChatGPT for recommendations. It recommended another coffee maker, so I bought it. And guess what? That one didn't make very good coffee either. Now I've got another coffee maker, I'm out more money, and Kristie is still making better coffee than I am. Wonderful.

That's when I decided to quit guessing and figure out exactly what she was using. The problem was that her machine was an older Keurig K500, a model I couldn't just walk into Walmart and buy new anymore. Kristie sent me photographs of her machine, including the model and serial number. We tried searching the serial number backward, comparing photographs, and looking for machines that matched hers. Eventually, I found a K500 on eBay and bought it.

Finally, I had the same model of coffee maker Kristie was using. You'd think that would be the end of the story. Not even close.

Down the Filter Rabbit Hole

Now we both had Keurig K500s, but her machine had brewing options mine didn't seem to offer. I started comparing settings, cup sizes, and how the machines behaved. We went through the menus, tried resets, unplugged the machines, and experimented with different reusable coffee filters. And I mean several filters. You would think a reusable coffee filter was a reusable coffee filter, but apparently not.

One had a white circular spot on the lid, while another had a reddish-brown insert. Some activated additional brewing settings, while others didn't. The filter that gave me all six brewing options wasn't necessarily the one that made the coffee I liked best. After brewing, the grounds in that filter were pushed up around the sides of the basket, leaving a funnel-shaped hole in the middle. It looked like the water might have been hitting the grounds harder or flowing through them differently.

I didn't have laboratory equipment proving any of that. I just knew what I was seeing, and I preferred the way my other filter brewed. Then I checked Kristie's filter and found the same funnel-shaped pattern, so apparently, that wasn't necessarily a defect. It was simply something different about how those filters behaved. But now I wanted the best of both worlds: the additional brewing options from one filter and the coffee from the other. Which, naturally, led to another investigation.

When Aluminum Foil Becomes Laboratory Equipment

I started looking closely at how the Keurig recognized its filters. There were these little circular inserts on the lids, one white and one reddish-brown. One filter also had a small square printed code. I wondered whether the machine was using an optical reader to identify what I'd installed, so I decided to see whether I could fool it.

First, I covered the brown circular area with white paper. Nothing changed. Then I tried aluminum foil, and the machine rejected the filter. Well, that was interesting. Next, I covered the square printed code on the other filter with foil, and the machine still offered all six brewing settings. Now I was getting somewhere. At least I knew that covering the printed code didn't prevent that particular filter from being recognized. I still hadn't completely figured out what the machine was looking for, but I was learning.

And at some point, you have to wonder how a grown man ends up standing in his kitchen putting aluminum foil on coffee filters. All I wanted was a good cup of coffee, and now I was trying to trick a coffee maker.

Eventually, I decided the filter with the white circle was the one I preferred. The grounds stayed more evenly settled at the bottom, and I liked the coffee it produced. Kristie preferred the filter with the reddish-brown circle, just like the one she used at her house. So at my house, we each have our own.

There's another reason for that arrangement. Kristie likes caramel-flavored coffee, and I don't want caramel flavoring getting into my regular coffee. At her house, we use the same reusable filter, but at mine, we've each got our own. Separate filters, separate coffee, and everybody's happy.

Maybe It Was the Caramel

Of course, I couldn't leave well enough alone. I started wondering whether some of the flavor I liked in Kristie's coffee might actually be coming from the caramel she'd been using for years. Sometimes she drinks caramel-flavored K-Cups, and she likes caramel creamer, too. I wondered whether traces of that flavoring could be hanging around in her reusable filter. After all, rinsing a coffee filter with water doesn't necessarily remove every bit of coffee oil or flavoring.

I even smelled the inside of her coffee container, and there was definitely a sweet aroma. Could that have been influencing the taste of my plain Maxwell House when I made coffee at her house? Possibly. Did I ever prove it? No. But it was another reasonable explanation, and I wasn't going to ignore it. Meanwhile, Kristie was probably still thinking the answer was pretty obvious. Her coffee was better because she made it.

The Great Coffee Competition

For quite a while, Maxwell House was my favorite. I'd gotten my Keurig making coffee I genuinely enjoyed, but after all this experimenting, I started wondering whether I could find something even better. I tried Chock full o'Nuts and didn't care for it as much. Then I tried Eight O'Clock coffee, and that didn't particularly impress me either.

Somewhere in the process, I managed to order ground Eight O'Clock coffee when I meant to order whole beans. I'd already ordered a coffee grinder. I tell people I'm good-looking. I never said I was smart. So now I had an OXO burr grinder, ground coffee I didn't particularly like, and whole beans on order.

But before those beans arrived, I stopped at Walmart and found Caribou Coffee. Medium roast, whole bean. I figured I'd give it a try. I poured some beans into the grinder, set it to medium, ground enough for a couple of cups, and put the grounds in my reusable Keurig filter. Then I brewed a cup and took a drink.

Well, I'll be damned. That was some damn good coffee.

But one good cup doesn't prove much. Anybody can get lucky once, and I wanted to know whether I could make another cup just as good. So I kept making it, and it kept tasting good. I did notice some fine sediment collecting in the bottom of my cup, so I adjusted the grinder a little coarser. That took care of the noticeable sediment without hurting the flavor.

Now I had a combination that worked consistently. Same beans, same grinder, same filter, and the same brewing routine. Every morning, I was getting coffee I actually looked forward to drinking.

The Maxwell House Rematch

After drinking Caribou Blend for a while, I decided to go back to Maxwell House. Remember, Maxwell House was the coffee I'd been trying to perfect all along. It was the coffee I originally thought tasted so good at Kristie's house. I made myself a cup, took a drink, and had one reaction. Gross.

Seriously, I couldn't believe it. The coffee I'd spent so much time trying to duplicate wasn't even what I wanted anymore. Somewhere along the way, I'd found something I liked better. At least, better to me. And that's the only opinion that really matters when you're the one drinking it.

What Did I Actually Learn?

I'd love to tell you I discovered the one secret that made Kristie's coffee so good, but I didn't. We never conclusively determined whether it was the water temperature, the machine, the filter, some trace of caramel flavoring, or a combination of things. And I can't claim that freshly grinding beans alone made the difference, because I changed the beans themselves, too.

But I learned a lot about coffee makers, reusable filters, brewing settings, grind sizes, and how small changes can affect the result. More importantly, I figured out how to make coffee I absolutely love. I started this whole thing trying to duplicate Kristie's coffee, and somewhere along the way, I ended up finding my own.

And here's the thing about me. When I get interested in something, I don't give up just because the first attempt doesn't work. I want to understand why something works, why it doesn't, and what I can change to make it better. Sometimes I find the answer, and sometimes I find a dead end, but I'm going to investigate it until I'm satisfied. That's just how I'm wired.

Was all this necessary for a cup of coffee? Probably not. Did I spend more money and time on it than any reasonable person would? Absolutely. But now I can walk into my kitchen, grind some Caribou beans, brew a cup, and know exactly what I'm going to get: a damn good cup of coffee.

And Kristie? I texted her and told her I was writing this whole ridiculous adventure down and putting it on my website. Told her she was in the story. Her response? "I better be in there."