Effects of Caffeine and Decaf Meaning
Caffeine is a stimulant and an appetite suppressant. It occurs in coffee naturally and is also present in other drinks and foods (tea & chocolate).
Some people (10% of American coffee lovers) love the taste of coffee but can’t deal with the effects of caffeine. Good news, as you know, caffeine can be isolated from coffee beans. But is this unnatural method (decaffeination) safe and good for your health ? Are the chemicals used in this process dangerous and hazardous ?
How is Coffee Decaffeinated and How Much Caffeine in Decaf Coffee?
First of all, "decaffeinated” does not mean 100% caffeine free. More than 97% of caffeine needs to be removed in order to label a coffee as decaffeinated, according to US guidelines. There is always a slight amount of caffeine left over from all the washing and processing. When we compare decaf vs regular coffee ; A typical cup of decaf coffee has about 2 mg of caffeine, compared to a typical cup of regular coffee, which has about 95 mg of caffeine.
The challenge of decaffeination is to try to separate only the caffeine from the coffee beans while leaving flavour precursors in as close to their original state as possible. This is not easy since coffee contains somewhere around 1,000 chemicals that are important to the taste and aroma of this wonderfully complex elixir.
Mainly 4 methods can be used to rid the beans of their caffeine but the most prevalent is to soak them in a solvent - usually methylene chloride or ethyl acetate.
There are some common priciples in all methods of decaffeination ;
• Green (unroasted) coffee is used in decaffeination process.
• Water is used in all forms of decaffeination.
Note that decaffeinated beans are notoriously difficult to roast properly.
Direct and Indirect Method (Solvent Based Process)
Chemical solvents (Ethyl Acetate or Methylene Chloride) are used in these methods. They are selective compounds, meaning they will bond with only the caffeine molecules in the bean, leaving the flavour molecules intact.
In the direct method caffeine is removed by soaking the materials directly in a chemical solvent; the solvent is directly applied to the beans.
The green beans are steamed, causing the beans to swell, increasing the beans surface area. This opens the “pores” of the beans, ready for the molecules to move in and out.
Beans are rinsed repeatedly with the chemical solvent to flush away the caffeine. (Soaked in water and then covered in a solution containing either Ethyl Acetate or Methylene Chloride)
The caffeine is then drawn out by the solvent while leaving other constituents largely unaffected. The process is repeated from 8 to 12 times until the caffeine content meets the required standard (97% according to the US standard, 99.9% according to the EU standard)
In the indirect method, the chemical solvent never touches the beans but treats the caffeine-laden water in which the beans have been soaked for hours. After the caffeine is removed from the water with the solvent, the bean-flavored solution is reintroduced to the beans, allowing many of the oils and flavors to be reabsorbed.
CO2 (Carbon Dioxide) Method
Supercritical CO2 decaffeination process is similar to solvent method, but instead, it uses carbon dioxide under high temperatures and pressure to act like both a gas and a liquid to extract the caffeine.
In the CO2 decaffeination process, water soaked coffee beans are placed in a stainless steel container called the extraction vessel. A mixture of water and carbon dioxide (CO2) is circulated through the vessel at 300 atm and 65 °C.
At high pressures, carbon dioxide becomes supercritical and becomes a solvent that is like a liquid but has the properties of a gas. When passing through the wet green coffee beans, supercritical CO2 reaches into the crevices of coffee beans like a gas but dissolves caffeine like a liquid.
Because this method leaves the carbohydrates and proteins intact, there is less change in taste as a result of decaffeination. But also, it is an expensive method.
Decaf Swiss Water Process
This process uses no organic solvents, and instead is based solely on water and carbon filtration.
A batch of beans are soaked in very hot water in order to dissolve the caffeine. The water is then drawn off and passed through an activated charcoal filter. The porosity of this filter is sized to only capture larger caffeine molecules, while allowing smaller oil and flavor molecules to pass through it.
The flavorless caffeine-free beans are discarded, but the flavor rich water is reused to remove the caffeine from a fresh batch of coffee beans.
Caffeine is thereby filtered from the beans without recourse to chemical agents and without the beans losing many of their flavorful components. This is the primary method used to decaffeinate organic coffee beans.
Is Decaf Coffee Bad or Good for You ?
There is no evidence to suggest that drinking decaf is bad for a person's health, and it may even share some of the health benefits of regular coffee.
All four methods are safe*, and once the caffeine is removed (well, at least 97% of it), the beans are washed, steamed, and roasted at temperatures that evaporate all the liquids used in decaffeination.
It is worth emphasizing a sensitive issue here; is decaf coffee safe during pregnancy ? There are no official guidelines on decaffeinated coffee and pregnancy. It is clinically proven that when caffeine is taken with beverages, it quickly passes into the body and goes to the baby through the placenta. When 200 mg of caffeine is taken into the body, the flow in the placenta, which sends blood to the baby, decreases by 25% and the caffeine passes to the baby. Since decaf coffee is not %100 deccafeinated, this should be taken into account.
* Methylene Chloride's use as a decaffeination agent is not considered a health risk. Food and Drug Administration has determined any potential health risk is so low “as to be essentially non-existent” (FDA, 1985).
* Ethyl Acetate is a natural fruit ether usually made from acetic acid (the building block of vinegar) It is more “natural” than other chemicals and safer than methylene chloride since it exists in minute quantities in ripening fruits, such as apples and blackberries.
There are a lot of myths and rumors surrounding caffeine but it isn’t as unhealthy as it was once believed. In fact, evidence shows that it may be just the opposite. Regulators and health authorities have concluded light-to-moderate (up to 400mg per day) caffeine intake seems to provide impressive health benefits for most adults.
Decaf coffee benefits are similar to regular coffee benefits., but none of the side effects. For example, drinking decaf coffee at night will not cause insomnia.
By the way, while each of decaffeination methods will take most of the caffeine away, there’s no such thing as a completely decaffeinated drink. Therefore, it’s safe to consider your daily cup of coffee as an enjoyable way to promote good health.