How is Coffee Decaffeinated?

Did you know that after water, coffee is the most popular drink worldwide with over 400 billion cups being consumed each year? Decaf coffee is great if you fancy a brew, but you don’t want to be up all night -but how is coffee decaffeinated? And is it good or bad? We are going to break it down and explain everything that you need to know about decaf coffee.

Contents

I - Understanding Caffeine in Coffee

II - Modern Decaffeination-Techniques

III - Health Benefits

IV - Evaluating Decaffeinated Coffee

V - FAQ's

Understanding Caffeine in Coffee

Caffeine is found in the leaves, seeds, and fruit of more than 60 different plant species, it is a mild stimulant which acts on the central nervous system and other organs of the body. Caffeine is readily absorbed into the bloodstream but doesn’t accumulate in the body.

The stimulant effects from an average-sized mug of coffee typically takes effect after 15 to 45 minutes and can last for around four hours. It can depend on a lot of factors though, including age, body weight, time of day and the person’s sensitivity to it.

Modern Decaffeination Techniques

Today there are four major methods of coffee decaffeination: Direct-Solvent Process, Indirect-Solvent Process, Swiss Water Process, and Carbon Dioxide Process.

Direct-solvent process 

This works as you would think; the beans come into direct contact with several chemicals that work to remove caffeine from the beans, these include the ethyl acetate and methylene chloride. To make this possible, the beans are steamed first to make them porous and receptive to the solvents. methylene chloride or ethyl acetate to bind the caffeine away from the beans, which can be disconcerting to some folks. However, considering the fact that coffee is roasted at 400+ degrees, and brewed at around 200 degrees, the likelihood of finding any traces of chemicals in a brewed cup of coffee is very low.

Indirect method

Beans are left to soak in hot water and once the water absorbs the caffeine and all the other components in the beans, it is transferred to a different tank where it is treated with a solvent. The solvent consumes only the caffeine, leaving the oils and flavour molecules in the water. The solvent containing the caffeine is then skimmed off the top of the water, never having come in direct contact with the beans. The flavour-laden water is then returned to the tank with the beans, where the beans reabsorb the flavours and proteins from the water.

The Swiss Water System

This is the only one that does not directly use any chemicals, introduced in 1933. The beans are steamed to release the caffeine and make it more accessible. Next, the beans are soaked in water that has been over saturated with coffee compounds and the caffeine is drawn into the water. The water can only hold so many flavour compounds, so soaking the second batch of beans the oversaturated water ensures that the coffee compounds in the second batch will not be released into the water, but the caffeine will. The water is then put through a charcoal filter which captures the larger caffeine molecules but allows the smaller oil and flavour molecules through. This results in decaffeination while maintaining the coffee flavour. The biggest benefit to the consumer was the consistency of great flavour in the coffee, but the planet benefited more. The production massively reduced the footprint left during decaffeination as around 75% of all the water used in the process can be returned to rivers and streams with no issue.

CO2 Decaffeination

This is the most modern system. The coffee beans are placed in a chamber and pressurised. When the CO2 dissolves, the caffeine is drawn out of the bean. The caffeine enriched CO2 is then extracted to a separate chamber, depressurised and returns to a gaseous state where it lets go of the caffeine. The CO2 can then be reused for more decaffeination. The lack of outdated chemicals in this system has benefits but the largest advantage to this system is environmental. The lack of water and reusability of the CO2 reduces the industrial footprint of decaffeination on the planet.

Health benefits

Evaluating Decaffeinated Coffee

Labelling regulations and standards for decaffeinated coffee

For coffee to be classified as decaffeinated, it must reach specific standards, primarily, a low caffeine content. The caffeine content should not exceed the required percentage of the total dry matter of the coffee, i.e., for every 100g of green coffee beans, the caffeine content should be a maximum of 0.1 grams.

Comparison of taste and aroma between regular and decaffeinated coffee

Usually decaffeinated and regular coffee will look and taste the same; both produce a beautiful crema on an espresso and are dark and rich in colour. Sometimes however there can be differences in the taste. Some decaffeinated coffee beans will produce a sour or salty aftertaste when drank. This is usually very slight, and many people wouldn’t notice it without really looking for it.

Considerations when purchasing decaffeinated coffee.

There are no set rules of what you should and shouldn’t look for when purchasing decaffeinated coffee, the key thing is to find what works for you. This may be a bean made using a process you agree with, one that is chemical free, or perhaps one that is decaffeinated and a dark roast. The key thing to think about is flavour; to find a flavour you like in a coffee and to go out and search for that bean without caffeine.

Frequently Asked Questions (FAQs)

Does decaf coffee have caffeine??

Regular coffee is a stimulant due to the level of caffeine it has in it. However, it is important to remember that decaf coffee is not completely caffeine free, so there is still a chance that you are going to get a lower level of that “buzz” feeling.

Does decaffeination affect the flavour of coffee?

Depending on the method of decaffeination used, the favour of the coffee can be affected. This is because the chemical agents used in the process bind to the coffee bean and are present during the roasting process. Processes such as the Swiss water system do not affect the flavour though.

Can decaffeinated coffee cause any side effects?

Decaffeinated coffee doesn’t cause dehydration as many believe, but that is not to say it has no side-effects. Headaches and drowsiness can occur depending how much coffee is ingested and, in some cases, it can cause gastric issues. These are not universal side effects but can occur through excessive consumption.

What is the recommended daily intake of decaffeinated coffee?

Research has proven that a moderate consumption of 4-5 cups of coffee per day is in fact safe for the general population. It has also been shown that caffeine can improve concentration, alertness, intellectual effort, and vigilance. For decaf coffee, this number can be higher as there is significantly less caffeine and therefore, less side effects on the nervous system.

You might also be interested in these:

- How is Coffee Made?

- Plant Based Milk Guide

- How To Use a Cafetière