Have you ever thought of re-using coffee grounds to brew a second or third cup of coffee? You are not alone. Good coffee does not come cheap, and many people require 2 or 3 cups of coffee a day.
As a result, some coffee drinkers wonder whether re-using coffee grounds will minimize the quantity of coffee they use.
You may think re-using coffee grounds to brew every second cup of coffee you take is a great way to save money ; but is that the right way to go? Let’s find out.
Are There Any Benefits to Re-using Coffee Grounds?
Unfortunately, you don’t get much flavor, caffeine, or aroma from re-using coffee grounds.
Fresh coffee grounds contain 10 -12 mg of caffeine in each gram of fresh coffee grounds. Once you brew your coffee, only about 3.59 – 8.09 mg of caffeine remain in each gram of used coffee grounds. You may think that’s enough caffeine to make a great cup of coffee, but it’s not. It will only give you a bland brew that does not meet your caffeine needs.
We also have to consider that the composition of coffee grounds changes once they are exposed to hot water. They release most of their flavors, oils, and aromas when you brew the first cup of coffee.
Therefore, any other coffee you make with used coffee grounds will be weak in terms of flavor and nutrients. That’s because it will lack most of the flavonoids, vitamins, antioxidants, and proteins found in coffee oils that are important for brewing great coffee.
If you insist on re-using old coffee grounds to brew coffee expect a bitter flavor due to over-extraction. The fruity and acidic notes of coffee are extracted when making the first cup of coffee, leaving behind the bitter flavor notes. The most you can expect from such grounds is a sour brew that will trigger stomach acidity.
Some people know these facts concerning brewing coffee with used coffee grounds. Therefore, they choose to minimize the brewing time when making their first cup of coffee to leave some beneficial compounds in the coffee grounds for a second cup.
Unfortunately, once fresh coffee grounds are used to brew the first cup of coffee, they absorb the hot water and release most of the ingredients. That means, you cannot divide the flavors and aromas you get from coffee grounds to make two batches of coffee, even if it seems like a good idea.
Some people also choose to dry used coffee grounds and re-use them again to extract the remaining coffee compounds left in them. They think drying the grounds will enable them to re-use the coffee grounds as if they are fresh. But these coffee grounds only result in an under-extracted, thin, and flavorless brew.
And although you may not know it, used coffee grounds can grow fungi and bacteria when left out in the open for some time after brewing coffee.
The moist and warm surfaces of the coffee grounds encourage the growth of pathogens such as fungi within 24 hours. Drinking coffee made from such grounds may cause gastrointestinal issues such as stomach pain, diarrhea, and vomiting.
For these reasons, we advise you not to re-use coffee grounds to make coffee. And that’s not only our opinion. The National Coffee Association also advises against re-using coffee grounds to brew coffee.
How to Recycle Used Coffee Grounds?
Although you can’t save money by using old coffee grounds to brew coffee, you can use them for other beneficial purposes.
Here are some suggestions on how to re-use your old coffee grounds.
Old coffee is an excellent addition to plant compost. These grounds contain nutrients such as chromium, calcium, potassium, nitrogen, phosphorus, magnesium, and iron that are essential for healthy plant growth.
Used coffee grounds also attract worms that are essential for aerating the soil and keeping away slugs and snails from vegetable gardens. They also repel harmful insects such as mosquitoes from gardens.
You must compost your coffee grounds for at least 90 days before using them in your garden. That will keep compounds such as tannin that are usually in freshly used coffee grounds from burning plant roots.
Coffee grounds are great for growing radishes, tomatoes, mushrooms, carrots, magnolias, roses, and rhododendrons.
2. Body Scrub
You may use plain coffee grounds as a body scrub or add some coconut oil, vanilla extract, and brown sugar to make a fragrant body scrub. It will leave your skin feeling vibrant and healthy.
The caffeine in coffee grounds boosts blood circulation and encourages the regeneration of skin cells. Using coffee grounds to exfoliate your scalp can also help you to get rid of product and dead skin build-up, promoting healthy hair growth.
However, avoid coarse coffee grounds because they will be too rough on your skin. The best coffee ground sizes for making an exfoliant are medium to fine coffee grounds.
You can use old coffee grounds to make a homemade deodorizer for wardrobes, lockers, fridges, or cars. Coffee grounds can eliminate foul odors and toxic gases from the air around you because they contain nitrogen which absorbs sulphuric gases associated with foul smells.
The strong coffee aroma also acts as a deodorizer, neutralizing any bad smells left behind after smoking or cooking with pungent-smelling foods such as garlic.
Anytime you need a deodorizer, just scoop coffee grounds into a bowl and leave them wherever you need to get rid of strong smells. They will absorb these odors, leaving the space smelling fresh.
You can also use them to scrub your hands after touching strong-smelling foods such as onions or fish.
4. Surface Scrub
You can use old coffee grounds with dishwashing soap to scrub stubborn stains off oven grills, pots, sinks, and other hard-to-scrub surfaces.
The abrasive texture of coffee grounds makes them ideal for scrubbing off stubborn stains, especially after burning food in a pot.
Coffee grounds can also kill bacteria and other pathogens on kitchen surfaces due to their antibacterial, antiviral, and anti-pathogenic properties. Just make sure you avoid cleaning light – colored counter tops with coffee grounds to avoid discoloring them.
5. Tenderizing Meat
Coffee also makes a perfect meat tenderizer due to its ability to break down the proteins in meat. The tenderizing properties of coffee come from tannin, which works the same way as wine in enhancing the flavor of the meat. It’s the reason coffee is regulary used when braising, smoking, and roasting meat.
You can also use coffee grounds in meat marinade recipes. They give beef a delicious crust by allowing the meat to sear properly.
Coffee can also enhance the flavor of meat due to its acidic properties. That’s why it’s often used as an ingredient in meat marinades along with spices such as paprika and black pepper. Use it in brisket recipes, prime roast ribs, or kebabs.
Now you know why you should avoid re-using coffee grounds to brew coffee and the benefits of recycling them. You no longer have to worry about wasting coffee grounds by throwing them in the trash.
Re-using coffee grounds is great for the environment. It reduces the coffee waste that contributes to greenhouse gas emissions in landfills all over the world. Therefore, the next time you think about throwing out used coffee grounds consider using them as we’ve suggested.