Can You Reuse Coffee Grounds? (Is Rebrewing Twice A Good Idea?)

Can You Brew Coffee Grounds Twice? 

Can you use the same coffee grounds twice? Yes. 

Should you use the same coffee grounds twice? No! 

Reused coffee grounds aren't dangerous, and if you make fresh coffee with them twice it isn't going to harm you. 

However, while it may seem tempting to use coffee grounds twice, it is not recommended. This is because of the brewing process and how used grounds impact the end product. 

When brewing fresh coffee the hot water comes into contact with the fresh grounds, dissolving them. All the oils and flavor compounds mix into the water and produce a wonderful cup full of coffee flavor. 

Unfortunately, when you carry out the same brewing method on reused coffee grounds it won't extract the flavor again. This means you won't get the full coffee taste you got with the fresh coffee grounds. 

In addition, 'over extraction' occurs when your ground are in water for too long, and when you use the ground twice this creates over extracted coffee. This results in the used coffee grounds making your brew harsh, bitter, and unpleasant tasting. 

If you dry the used grounds first before you make a second cup of coffee to prevent over extraction it can lead to under extraction. This leaves you with a weak, sour tasting cup of coffee which no coffee drinker will enjoy. 

Generally, you shouldn't use coffee grounds twice, but every brewing method is slightly different. We've tried and tested popular methods to see how it turns out.

Can I Reuse Coffee Grounds For Cold Brew? 

Cold brew coffee is the exception to the rule, and reusing coffee grounds for a cold brew works fine. 

This is primarily because cold brew coffee is made using cold water. This means the extraction from the fresh grounds isn't as harsh, and fewer of the oils are destroyed. So, when you come to reuse the old coffee grounds there's still flavor to be absorbed. 

The only real difference is how much caffeine is extracted from old coffee grounds. 

Cold brew coffee is typically very strong, however, when you reuse old coffee grounds it won't pick up as much caffeine from the coffee beans. It will still be fairly strong, but it won't have the strength and deep flavor of a fresh cold brew.  

Even though you can use the coffee beans and old coffee grounds twice using the cold brew method, never use them a third time. This will create a really weak cup of coffee with no real taste - and nobody will enjoy that.

Can I Reuse Coffee Grounds For French Press? 

It's not recommended, but you can reuse the coffee grounds from your French press for another steep. 

However, you shouldn't expect to get the same cup of coffee twice. The second brew will be less full bodied, and have less caffeine. You'll probably notice how much odor is lost from the coffee in the second batch too.

If you are planning to reuse ground coffee to make French press then you should use them straight away. You'll get better extraction immediately from the wet grounds, and while it won't be a perfect cup, it will taste less bitter. If you wait longer than 15 minutes it will not taste good! 

It's still recommended that you use fresh ground coffee for French press coffee, but in a pinch it's ok to reuse coffee grounds. 

Can I Reuse Coffee Grounds For Drip Coffee? 

Drip coffee is one of the most popular types of coffee, and many homes and offices have a drip coffee maker. 

As with other brewing methods, you shouldn't use old grounds for drip coffee. 

Again, this all comes down to the coffee extraction process. As water drips through the grounds a first time it captures the flavors and creates an enjoyable cup of coffee. 

If you let the water drip through the spent grounds again it won't capture the flavor as you brew coffee. This will leave your second cup of drip coffee weak, sour, and not enjoyable to drink.

Comparing Coffee Made With New Vs Used Grounds 

To help understand the differences between coffee made with new and used grounds we've examined them in 3 different categories: taste, caffeine content, and color. 

Here are the results:

Taste and Flavor

New coffee grounds brew a bold and intense cup of coffee. There is a pleasant aroma and a strong, complex flavor from the fresh grounds. 

Coffee made with used grounds lacks flavor and aroma. The coffee extraction from the first brew has already extracted the oils, leaving almost nothing to the second brew. 

That's why when you brew used grounds, you essentially have dirty water. The second brew won't even taste like coffee. Some people may say that it's not "drinkable." 

Caffeine Content

When you brew a coffee with fresh grounds you extract approximately 50% of the caffeine from the grounds (though this can vary depending on the brewing technique and grind size).

When you brew again with the same grounds you extract far less caffeine as the remaining 50% of the caffeine can't be extracted in the same way. 

You may get some caffeine from the used coffee grounds, but the caffeine concentration is far lower and you'll get weaker coffee. 

Color

New coffee grounds produce a dark, robust, and almost intense dark brown drink. All the oils and natural ingredients are extracted into the hot water, leaving you with a deep colored brew. 

When you reuse the coffee beans it gives you a pale, watered down coffee that looks more like a cup of tea. This is because all the ingredients have already been extracted and the crucial elements are gone. 

Other Ways To Reuse Coffee Grounds 

Just because you shouldn't brew twice with coffee grounds doesn't mean you can't make the most of them. 

Here's some of the best ways to reuse coffee grounds and still get loads of benefits from them:

Hand & Body Scrub 

Coffee grounds can naturally exfoliate the skin. It also has antioxidant properties that can remove dead skin cells. This is why the coffee grounds can be used as a hand and body scrub.  

Here's how to make and use the scrub:

• Combine 1 cup of coffee grounds from your brewed coffee, 6 tbsp coconut oil or jojoba oil, plus 3 tbsp sea salt or white sugar into a bowl or a jar
• Mix everything thoroughly until everything is combined thoroughly
• Apply it to your face, hands, body, or any part of your body you'd like to exfoliate
• Gently rub the grounds on your skin and rinse off when done

Note: Avoid washing coffee scrubs down your drain. If you are going to use the scrub in the shower, it is best to place a fine-mesh sieve over the drain to catch the grounds and throw them in the trash.  

To Remove Unpleasant Odors 

Coffee grounds have nitrogen, which can help remove foul-smelling sulfur gas from the air when combined with carbon. Simply put, coffee grounds can help absorb and eliminate unpleasant odors.

Here's some easy ways to use coffee grounds as air fresheners in your home: 

• Deodorize your fridge or freezer by placing a bowl of coffee grounds inside. This will neutralize odors from spoiled or fragrant foods.
• Make portable air fresheners by putting the grounds in old socks or pantyhose and tie the ends to seal.
• Place these portable air fresheners in your car, gym bag, or in drawers to manage the smell around your home.

Cleaner For Pots & Pans 

Do you have pots and pans that require a thorough cleaning? Coffee grounds can be our best friend.

Dry, used coffee grounds are abrasive and acidic enough to remove burnt-on gunk from pots and pans. Here's the best way to do it:

• Soak the pans in hot water for 30 minutes to loosen the gunk. You can also add brown sugar or baking soda to help. 
• Gently run the grounds to remove the stains and residue.  

Note: Coffee grounds are not recommended for glossy or nonstick surfaces. At the same time, don't scrub your cookware with force. Only use coffee grounds when you want to use steel wool for your pots and pans.  

Don't flush your coffee grounds down the sink or it can cause big issues for your plumbing.

Fertilizer 

As mentioned, coffee is acidic, and some plants benefit from acidic soil. That's why you can reuse your coffee grounds as fertilizer to help cultivate a healthy ground for acid loving plants.

Vegetable gardens that have tomatoes will benefit the most from acidic soil, but certain flowers (like magnolias) will also thrive in acidic soil. 

To use coffee grounds as a fertilizer simply: 

• Sprinkle the coffee grounds on top of the soil, or mix them with it. 
• Spread it evenly around the plants, but not too thickly or it can stop water draining. 
• Leave it to work its magic!

Coffee Candle 

If you love the smell of coffee, you can use the coffee grounds to make DIY coffee candles. By  

Making your coffee candle, you can fill your house with that energizing, wonderful coffee aroma you love. You can even use a coffee mug to spice up your DIY candle. All you need is candle wax, a wooden stick, and your used coffee grounds.  

Animal Repellent 

Coffee grounds can also help repel pesky insects from your garden. Some insects and animals find the coffee aroma too strong, which deters them from your plants.

Sprinkle the grounds in your garden so insects, particularly snails and slugs, and animals, like chipmunks, will not devour your plants. This will prevent them from damaging your garden. However, be careful with using coffee grounds as an animal repellent.

Some insects are essential to a healthy garden, and completely removing them can create more harm than good.   

How To Safely Dispose Of Coffee Grounds

However, if you don't want to, or can't reuse your coffee grounds you should always throw them directly in the trash. 

Never throw your coffee grounds down the sink or in your garbage disposal as it can clog the disposal and the plumbing. This can lead to expensive repair work. 

People Also Ask (FAQs)

How long till used coffee grounds go moldy? 

It is best to check your grounds every 1 to 2 months for mold growth. However, if you store them properly, they can last for a year or two.  

Do you use used coffee grounds for cellulite? 

You can use coffee grounds to reduce the appearance of your cellulite. This is because coffee can stimulate dilation while the scrubbing motion increases blood, making the skin look plump and the cellulite less noticeable. However, the effects are only temporary.  

Can you use the same coffee filter twice? 

Yes, you can use the coffee filter twice. You can even use it up to four to five times before it stops working effectively. Unlike coffee grounds, you can stick the filter back again even after using it. For best results, rinse off the filter and dry it before using it again.  

Conclusion

If you reuse old coffee grounds it will almost always make a bad tasting cup of coffee. The only exception is with cold brew, but it will still be weaker and less full bodied than your first batch. 

Coffee grounds can easily be reused in a number of ways, but it's best to only use them for coffee once. Hopefully this guide has introduced some useful ways to reuse them, and you now know how to make the most of your coffee grounds.