Can You Reuse Espresso Grounds? Brew Twice?

Making espresso uses a lot of grounds to make a tiny bit of coffee. Isn’t it possible to reuse those grounds and get another good cup of coffee? Here’s what you want to know.

While espresso uses a lot of coffee grounds to brew a small amount of liquid, that doesn’t mean they can be reused to brew again. Espresso machines extract everything from the coffee grounds in a very fast and efficient manner. After brewing there is not enough ‘taste’ left to brew another good cup.

How does this work exactly and are there any other things you can do with used espresso grounds? Find out below.

Can You Brew Twice With Espresso Grounds?

It’s a bad idea to brew coffee twice with used espresso grounds. You might think that you have to use a lot of coffee grounds for just a tiny bit of espresso. And that’s true. To make  espresso a ratio of about 1:2 is used which means one part grounds for two parts of liquid in the cup by weight. Other methods like pour over will use much higher ratios around 1:15.

Suggested: Why is espresso so strong?

To brew a normal 28 ml espresso, about 14 grams of coffee grounds is used. If you’d use 14 grams to brew a pour over, you could make 210 ml of coffee. So if you only make 28 ml of coffee with the same grounds, isn’t there a lot left in the grounds?

No. Espresso grounds are just as ‘spent’ as pour over coffee grounds after brewing. An espresso machine extracts the grounds very quickly and efficiently in a way you need less water and time. That’s why espresso is so concentrated. That means there isn’t much left after brewing. Whatever soluble compounds are left in the grounds after brewing will be the very harsh bitter ones so that doesn’t brew a good tasting cup of coffee.

Find out next why that’s the case.

Extraction

A coffee bean consists of insoluble and soluble materials. Most of a coffee bean is made up of cellulose which doesn’t dissolve in water. The cellulose makes up the cell walls of the coffee beans. What you want is inside. There is about a quarter of the coffee bean that can be dissolved in water. These are all kinds of different compounds and oils that are naturally present in coffee beans.

By roasting and grinding the beans those compounds are made easier accessible for the water to extract. Getting those soluble compounds into the water is what brewing coffee is. There are tons of ways to do this, an espresso machine is just one.

Suggested: What do you need to make good espresso?

Something to understand is that not all the soluble materials dissolve at the same rate. You can see this when brewing espresso. The first liquid is very thick and dark and then the liquid becomes lighter. That’s not only because most of the solubles are extracted but also because the later ones comes out slower and are lighter in color.

The different compounds dissolve into the water at  different rates and the different compounds provide different parts of the taste to the coffee. In general the compounds that are extracted first provide a lot of sourness to the coffee. So if you stop extracting too early, your cup will taste a little like biting a lemon. Some acidity is a good thing in coffee. It can make a bright fruity taste. But just plain sour is not enjoyable.

Once you extract more from the coffee, the compounds that come after balance out the taste so you get a more enjoyable cup of coffee. However, you can go too far. You don’t want everything that’s soluble from the coffee bean because the last stubborn compounds often give a very harsh bitterness to the coffee. Getting the right level of extraction is important, that’s what makes good tasting coffee.  

Suggested: Why is my espresso so bitter?

So, let’s say your brewed a good tasting espresso and want another one but you want to use the same grounds. What happens now is that a lot of the compounds that make good tasting coffee are already gone. All that’s left is the really bitter ones. If you try brewing twice with the same grounds, you’ll get a pretty weak cup that tastes ‘hollow’ but with a very unpleasant harsh bitterness.

What uses are there for spent espresso grounds

So brewing twice with the same grounds is a bad idea if you value the life of your taste buds. But that doesn’t mean you have to throw it away. There are some great uses for spent coffee grounds that are not brewing coffee.

There are actually a ton of uses for spent coffee grounds you didn’t know about. Here are some of my favorites but this is by no means an exhaustive list:

1. Cleaning abrasive: Adding coffee grounds to hand or dish soap, it provides an abrasive that makes cleaning stubbornly dirty hands and pots a lot easier while being more gentle than something like steel wool.
2. Absorbing odor: Coffee grounds are great at absorbing nasty odors. Put spent grounds in an open container and put it in the fridge to get rid of some nasty smells. Of course it’s not a replacement for cleaning properly but it’ll help in a pinch.
3. Insect repellant: Insects are not as big a fan of coffee as you are. Leaving it in the open can help but it’s best to put a little bit in an essential oil burner. Using the ones with an open flame works best. The electric ones might not like coffee grounds as much. You can also sprinkle grounds through your garden and around plants. It’s good to use in the garden anyways.
4. In the garden: There is a surprising amount of benefits for coffee grounds in the garden. It can help composting, reduce the PH level of your soil, be used to grow mushrooms on and more.
5. Body scrub: Coffee grounds can be used as a body or face scrub. It’s a much more environmentally friendly alternative to scrubs that use micro plastics.

Note: There are also a ton of coffee grounds uses for skin health. However, I’d recommend using fresh coffee grounds for those uses. Most of the skin health benefits from coffee come from the caffeine. Caffeine is quite easy to dissolve in water so after brewing with grounds, most of the caffeine will be gone. So if you want to make a scrub with the full benefits of caffeine, it’s best to use fresh grounds.

However, since you’re not going to drink this anyways, the taste of the bean doesn’t matter and you only care about caffeine. For that reason it’s a good idea to use Robusta beans for body scrubs. The caffeine content of Robusta beans is about twice that of Arabica and it’s cheaper to boot. And since you’re not going to drink it anyways, us a lighter roast. Usually Robusta is roasted dark to get rid of some of the bad tastes present in them. However, roasting darker also reduced the caffeine content. So light roasted Robusta would be great to use for body scrubs.