One-cup brewers feel like the answer to any coffee lover’s prayers.
Combining the convenience of instant coffee with a range of artisan-sounding flavors, they’re a modern day miracle. But how does a Keurig actually work?
If you’re like us, understanding how the coffee you’re drinking has been made is part of the enjoyment. What’s more, knowing how the Keurig works means knowing how to keep it in tip-top condition. That means a longer life for your machine, and more coffee for you!
So we’re going to explain just what happens in your Keurig to turn those plastic pods into a reliable cup of coffee.
What is a Keurig?
Let’s start by looking at what a Keurig actually is.
Simply put, it’s a brewing machine that produces a single cup of coffee at the touch of a button. If you’re a Keurig owner, you won’t be buying whole or ground coffee. Instead, you’ll purchase small plastic pods known as K-cups. These are what hold the coffee. (1)
The idea for the Keurig came from a man called John Sylvan. Like many inventors, he saw a problem he wanted to solve. Sylvan hated the drip-brewed coffee served in offices, kept on warming plates whilst it grew staler by the minute.
He imagined a machine that would produce a single cup of coffee quickly and easily. It would be even simpler to use than existing brewing machines. And no office worker would ever again have to drink stale coffee.
After lots of experimentation, he succeeded in developing a machine and coffee pod. The Keurig was born. (2)
With investment from Green Mountain Coffee Roasters and venture capitalists, the company grew. Unfortunately for Sylvan, he didn’t get on with the new investors. He left Keurig in 1997, selling his stake for just $50,000.
How do the K-cups work?
We’ve already heard that the coffee itself is housed in a capsule called a K-cup. This is a small plastic cup with a filter inside. The coffee grounds are placed inside the filter and the capsule is covered tightly with an aluminum foil lid. Take a look at this YouTube video to see the components. ()
The capsule is completely airtight, so there’s no danger of oxygen, light or moisture staling the coffee. In theory, that means it can stay fresh for months or even years.
One big problem is that the pods are not widely recyclable. Green Mountain has committed to remedying that by 2020, but for now, the environmental impact is a cause for concern. (3)
If you’re a Keurig owner, you can do your part by purchasing the My K-Cup pod, which is reusable. It can also be filled with any kind of coffee, so it opens the door to lots of new flavors.
Alternatively, you can buy a Zero Waste Box. This holds up to 600 pods and when full can be sent for recycling. It will handle pods from other types of beverage maker too. (4) So if you have friends with a Nespresso or Dolce Gusto, why not club together to buy one?
How does the brewer work?
There are lots of different models of Keurig on the market, but they all work along the same principles. And they’ll all give you a consistent cup of coffee in less than a minute.
To do this, the Keurig combines elements of two different brewing processes: espresso and drip brewing.
The water is held in a large reservoir, meaning that the machine doesn’t have to be regularly refilled. The Keurig will have two or three different buttons, depending on how much coffee you want. Press a button and the water will be forced at pressure through hoses and into a heating chamber. (5)
When it reaches the right temperature, the water passes through another hose into the top of the brewer.
The K-cup sits in its own compartment, which has a handle to open and shut it. When the compartment is closed, a sharp needle pierces the top and bottom of the K-cup. The hole at the top lets in the hot water, and the one at the bottom allows the brewed coffee to flow out. (6)
The Keurig forces hot water into the K-cup under pressure. The pressure isn’t quite as high as in an espresso maker, but it still extracts the coffee far more quickly than drip brewing. 8 to 10 ounces of water will pass through the coffee grounds in less than a minute. (7)
But while the brewing process may borrow from espresso, clean-up is completely different.
If you were using an espresso machine, you’d need to give it a sharp tap to release the coffee puck. Then you’d have to remove the basket from the portafilter and rinse both items thoroughly under running water. Finally, you’d need to dry them carefully with a soft cloth.
And that’s before you get to the process of cleaning the gasket and screen, and the regular deep cleans. (8)
With a Keurig, there’s none of that. All you need to do is lift the handle and remove the K-cup. There’s no easier way to make coffee.
How to get the best from your Keurig
Now that you know how the Keurig works, you may have spotted some potential flaws in the process. Here’s how to fix them.
Remember that whatever brew size you select, you’re using the same amount of coffee. The K-cup doesn’t get any bigger because you’ve pushed the button for a larger serving! That means a longer drink will have a higher water to coffee ratio, and will taste weaker. If you want a stronger taste, simply dispense two smaller servings using two different pods.
Then there’s the temperature achieved by the heating chamber. According to Keurig, its K575 machine heats water to between 187 and 197 degrees Celsius. But when put to the test, one group of coffee lovers couldn’t get a temperature higher than 187 degrees. (9)
In fact, it’s very common to hear complaints that Keurig-brewed coffee isn’t quite hot enough. There are plenty of ways to deal with this.
First and foremost, don’t dispense your coffee into a paper cup. They lose heat very quickly – as much as ten degrees within minutes. If paper cups are all you have, double them up to slow down the heat loss. And of course, using a lid if you have one will also help. (10)
If you’re using a ceramic or stainless steel mug, another simple tip is to warm it up first. Select the water-only setting on the Keurig and use it to fill your cup. Then flush it away and you’ll have a vessel that will keep your drink hotter for longer. A thermal travel mug with a lid is even better.
And some Keurigs also give you an option to select the water temperature. If you have a machine that lets you do that, always select “high”. Similarly go for “strong” if you have the option of a brew setting. That will give you another 30 seconds of brewing time and help extract all the good coffee flavors.
Choose the best coffee blends for your Keurig
Because the Keurig focuses on speed and convenience, some types of coffee work better than others. Dark roasts cope better with the risk of under-extraction from the fast process than light roasts.
But the real beauty of the Keurig is the variety of coffee flavors you can sample with very little fuss or expense. Experiment with different blends to find the one that suits you. And if you’re looking for a place to start, there are lots of taste tests out there that can help.
Flavors scoring highly with coffee lovers include the San Francisco Bay One Cup Fog Chaser and the Diedrich Coffee Dark French Roast.
Taking the top two spots in one test were coffees from Green Mountain, manufacturers of the Keurig. Their Kenyan AA and Sumatran Reserve were awarded almost 100% by tasters. (11)
How To Keep Keurig clean
With so many parts in contact with water, descaling your Keurig is essential to maintaining it in good working order. If you’re using it regularly, aim to descale at least once every six months. If you’re in an area with hard water, it might need to be more like once every three months.
You can purchase a descaler or use a simple mix of vinegar and water. This YouTube video shows you how it’s done.
If you find your Keurig is clogged, coffee grounds may have worked their way into the space around the needle. Try using a paperclip to clean them out. You can learn how to do it in this YouTube video.
We think the Keurig is a great way to get a reliable cup of coffee with the minimum of effort. By understanding how it works, you can make sure you’re getting the best from your machine.
And remember, it’s possible to purchase refillable K-cups! Not only will you minimize your impact on the environment, there’ll be no restrictions on the coffee you can use.
If you have any questions, please leave a comment and let us know.
My name is Kathy Gallo, Editor of Daily Cupo, a Coffee buff. The guide you find here is designed exactly for you, and it is our hope that you find it not only interesting but also actionable.