Does decaf coffee have chemicals in it?
Introduction
Decaffeinated coffee, commonly known as decaf, is coffee that has gone through a process to remove most of the caffeine while trying to maintain the flavor. Many coffee drinkers choose decaf for health reasons or to avoid the stimulant effects of caffeine later in the day. But some have concerns that the decaffeination process involves adding potentially harmful chemicals. This article will examine what chemicals are used in decaffeination, if any remain in decaf coffee, and the potential health implications.
Common Methods of Decaffeination
There are four main methods currently used to remove caffeine from coffee beans:
Swiss Water Process
This chemical-free method uses water and charcoal filters to extract caffeine while leaving flavor compounds behind. The beans are soaked in hot water which draws out the caffeine and flavor elements. The water is then passed through charcoal filters which absorb only the caffeine molecules. The caffeine-free water is reused to soak more beans. This cycle repeats until the beans are 99.9% caffeine-free.
CO2 Process
This method uses pressurized carbon dioxide in either a liquid or supercritical state to remove caffeine. The carbon dioxide acts as a solvent and selectively pulls out caffeine while leaving other compounds behind. The carbon dioxide along with the caffeine is later removed from the beans.
Organic Solvent Process
Coffee beans are soaked in an organic solvent such as ethyl acetate which absorbs the caffeine. The beans are then steamed to remove the solvent. The solvent is reused to extract caffeine from more beans.
Water Process
Also known as the indirect-solvent method, this involves soaking beans in hot water then using an organic solvent such as dichloromethane or ethyl acetate to extract caffeine from the water. The water and beans are separated before the organic solvent is added. After extraction, the beans are steamed to remove any residual solvent.
Chemicals Used
The Swiss water and CO2 processes are chemical-free, using only water, charcoal filters, and carbon dioxide to remove the caffeine.
The other two methods use organic solvents including:
- Dichloromethane (methylene chloride)
- Ethyl acetate
- Activated carbon (charcoal)
These solvents are removed from the decaf coffee beans after the caffeine extraction phase except for tiny residual traces.
The FDA monitors the use of solvents in decaf coffee and allows only minimal trace levels in the finished product.
Allowable solvent residue limits:
| Solvent | Limit (parts per million) |
|---|---|
| Ethyl acetate | 10 |
| Methylene chloride | 10 |
As a comparison, chemicals like ethyl acetate and dichloromethane are naturally present in foods we eat every day:
| Food | Ethyl Acetate Level (parts per million) | Methylene Chloride Level (parts per million) |
|---|---|---|
| Banana | 56 | 2 |
| Butter | 2 | 3 |
| Chicken | 1 | 5 |
This shows that the tiny amounts of solvent residues allowed in decaf coffee are minimal compared to the levels naturally occurring in many foods.
Health Concerns
Some people worry that small amounts of chemical solvents like dichloromethane may remain in decaf coffee after the decaffeination process. Dichloromethane was linked to cancer in lab rats when inhaled in large doses. However, the Food and Drug Administration (FDA) considers the miniscule amount of dichloromethane residues allowed in decaf coffee to be safe for human consumption.
A review of over 200 studies found no increased cancer risk associated with drinking decaf coffee or tea. Moderate caffeine intake up to 400 mg per day (around 4 cups of decaf coffee) has not been shown to have significant long-term health risks for most healthy adults.
Pregnant women are often advised by doctors to limit caffeine intake to under 200 mg per day. Decaf provides a safer alternative to regular coffee with trace levels of caffeine well under this limit.
People with certain medical conditions like arrhythmias are also sometimes told to avoid caffeine. For them, decaf can provide the taste of coffee without the stimulant effects.
Decaf Processing Methods and Chemical Use Overview
| Method | Chemicals Used | Chemicals in Finished Product |
|---|---|---|
| Swiss Water Process | Water, activated carbon | None |
| CO2 Process | Carbon dioxide | None |
| Ethyl Acetate | Ethyl acetate | Trace ethyl acetate |
| Methylene Chloride | Methylene chloride | Trace methylene chloride |
Decaf vs Regular Coffee Caffeine Content
While decaf has the vast majority of caffeine removed, there can still be small amounts left over:
| Beverage | Caffeine Content |
|---|---|
| Regular brewed coffee (8 oz) | 70-140 mg |
| Decaf brewed coffee (8 oz) | 2-12 mg |
| Regular Espresso (1 oz) | 47-75 mg |
| Decaf Espresso (1 oz) | 0-6 mg |
As you can see, decaf coffee has about 1-2% of the caffeine content of regular coffee. Some people are more sensitive to caffeine than others, but such small amounts in decaf are not likely to cause issues for most people.
Choosing a Decaf Method
If you want to avoid chemicals entirely, look for decaf processed using the Swiss water or carbon dioxide methods. These do not use any solvents.
If you buy decaf processed with methylene chloride or ethyl acetate, rest assured the residues are tightly regulated and minimal. But if you still have concerns, organic solvent methods can be avoided.
High-quality specialty coffee brands will often specify which decaffeination method was used, so check labels and descriptions when buying decaf.
Conclusion
While all decaffeination methods involve removing the majority of caffeine from coffee beans, only two use no chemicals at all. The other methods use solvents like methylene chloride and ethyl acetate but leave only trace residue amounts in finished decaf coffee. These residue levels are considered safe by health authorities and do not present a significant risk to consumers. Drinking moderate amounts of decaf coffee has not been shown to increase the risk of cancer or other health problems. The choice between decaf methods comes down to personal preference regarding chemical use. Seek out coffees that specify a chemical-free Swiss water or CO2 decaffeination process if you want to entirely avoid solvents. But rest assured the decafs decaffeinated using solvents are just as safe due to tight regulation of chemical residues.