How there’s up to 7mg in decaffeinated coffee which are sold as being stimulant free

It was news that shocked every coffee lover in Britain — certain high street chains pack their cups with a lot more oomph.

Immediately, questions were asked about the beans sold in supermarkets and just how much of a caffeine boost you are getting in your average cup of instant. 

But one fascinating fact re-emerged in the quest to understand the composition of our coffee.

And that is: there’s technically no such thing as ‘decaf’.

Instead, all options sold as being stimulant-free are actually merely extremely low-caf alternatives.

Some can even contain as much as a chocolate bar. 

Pret tops the list, in regards to high street chains. Its decaf option contains 6mg of caffeine per 50ml shot — its standard measure, MailOnline was told. 

Meanwhile, versions at Costa and Café Nero contain 2mg of caffeine.

Starbucks comes bottom of the table, though, with 1.4mg in every standard-sized decaf coffee.

A similar theme exists for instant coffee. Nescafe stated there is under 5mg in a mug of their instant decaf coffee. 

But if you’re drinking decaf to avoid the powerful pick-me-up effects of caffeine, rest assured that the minute amounts in decaf won’t disrupt your sleeping pattern too much, should you have one in the afternoon. 

The average cup of regular coffee has 30 times as much caffeine, with about 100mg.

Two shots of decaffeinated coffee at Costa contains just 2mg of caffeine, the coffee chain reveals in its allergen information. But it’s caffeinated cappuccinos contain up to 325mg

Cappuccinos at Costa even contain up to 325mg, the fascinating audit by consumer champion Which? revealed earlier this month. 

Meanwhile, the NHS says green tea can have around 75mg and energy drinks like Red Bull up to 80mg. 

Even milk chocolate, made from cocoa beans which also contain caffeine, can have 25mg for every 100g.

This would, in theory, amount to a 25g bar containing 5mg.  

So why do decaf beans still contain caffeine? 

Well, it’s impossible to fully make coffee decaffeinated, according to Dr Neil Clarke, from the Institute for Scientific Information on Coffee.

He said: ‘Coffee is decaffeinated through methods which mainly employ organic solvents, water, or supercritical carbon dioxide to remove nearly all caffeine. 

‘Multiple rounds of extraction typically take place, but it is not feasible to remove every molecule of caffeine.’

That said, there are stringent laws on how much caffeine can be in decaf products, according to Dr Clarke. 

In the EU, only 0.1 per cent of caffeine should be found in decaf green (unroasted) beans, and only 0.3 per cent in coffee products such as instant coffee. 

Similarly, the USDA states that any decaffeinated product must be a minimum of 97 per cent caffeine-free.

But the small amount of caffeine that is left in is unlikely to give you much of a buzz.  

In fact, most research suggests that 3mg per kilogram of body weight is what is needed to feel a buzz, Dr Clarke said. 

That equates to around 210mg for a 70kg (154lbs) person — or two regular coffees. 

He said: ‘Low doses of caffeine have been shown to improve vigilance, alertness and mood, and improve cognitive processes during and following strenuous exercise. 

‘Therefore, low amounts are highly unlikely to have the same beneficial effects.’

The European Food Safety Authority (EFSA) states that a moderate daily amount of caffeine (up to 400mg or 3-5 cups of coffee) is safe for most people.