The BBC website this morning reports a British research study has found widely-varying caffeine levels in coffee-shop espresso (from 50 mg in Starbucks to 300 in a French patisserie) and suggests this requires caution, above all from pregnant mothers, who are recommended to restrict their intake to no more than 200 mg per day.

You can read the full article here: http://www.bbc.co.uk/news/uk-scotland-glasgow-west-15968515

I know, shocking ins't it?

There are now rumblings on TV about "shops should analyse their coffees and post the caffeine content so the public are aware".....

It fills me with pride. Heaven knows what Shakespeare would have said....

The data in the paper is clearly presented; very much worth the free sign up to the journal if anyone is interested in seeing the results.

They say they ordered "single servings" of espresso, but received drinks with volumes ranging from 23-70ml (presumably measured after the crema has died down). It sounds like many of the stores actually served them doubles, which means we probably have a set of data ranging from a 7g single at Starbucks, to perhaps 20g+ doubles at other places.

Add blends with different roast levels and robusta content, and the study speaks more to the extreme lack of standardization for espresso preparation outside Italy than anything else. I guess this is what they set out to prove? I'd be interested to know exactly what wording they used when ordering the drinks (e.g. "a single" vs. "an espresso").

It seems to me to be exactly what they set out to achieve.

It's kind of like going to a bunch of burger joints and ordering "a burger" and reporting back that the nutritional content of burgers varies a lot.