The Dangers of Coffee Drinking – Allegedly.

Journalists top the coffee-drinking league table despite health risks shrieks the Guardian, going on to get its knickers in a right old twist, panicking about the “health risks” based on research carried out by the South Carolina university. I’ve had a look at it (it’s here), and it’s based on a study of a mere 27 people, meaning that any conclusions reached are statistically worthless.

How much caffeine one gets per cup or mug depends on the style of coffee, on the beans, on the grind, and on the quantity consumed. Assuming the same beans, same size mug/cup – the grind will vary with style – caffeine content varies wildly depending on how long the hot water is in contact with the ground coffee. Espresso is the lowest (highly controlled, ready in seconds), and percolated the highest (no control – depends how long it’s left on the stove), of normal coffee styles. These days, however, most people drink filter coffee, French Press, or espresso (which includes the whole range of espresso-based milky drinks).

US filter coffee, though, is notorious both for its high caffeine content, exacerbated by the often vast size of the portions, so any research based on US habits** will not translate in any meaningful way into, say, my habits. Or yours.

**Watch any US TV show, especially cop shows – invariably some of the characters will be wandering around with cardboard mugs of coffee the size of a baby’s head! You simply don’t see that in other countries, not on the same scale, anyway.

I drink a maximum of 3 200ml mugs of caffè crèma a day (a very long espresso – think of an Americano, but no hot water, just all coffee), using freshly-ground Old Brown Java beans and a Gaggia Classic espresso machine. NB: If coffee causes you heartburn, do try OBJ, the maturing process strips it of most of its acidity

I also have a serious heart condition which filter or French Press coffee kicks dangerously into tachycardia territory due to the much higher caffeine extraction. Everyone knows, especially when waiting for it, how long filter coffee takes to fill the pot – the water is in contact with the coffee for all of that time, sucking out the caffeine (while, if a paper filter is used, it will strip out most of the aromatic oils, and much of the flavour with them); an espresso, by comparison, take less than half a minute (my caffè crèma takes about 65 seconds). My own coffee, while lacking nothing in flavour, has zero effect on my heart because of the naturally low caffeine content. Hell, sometimes it doesn’t even keep me awake.

So the point to all this is what the guys at South Carolina U did will never translate into useful data for British hacks at the Guardian to worry about.


On a different note, when I started tinkering with coffee again recently – I had an abortive flirtation with espresso about 4 years ago, this time I’ve got it right – I stumbled across the Rule of 18 – and promptly lost it again, nor could I recall it accurately. Then, a few days ago, I found it.

What am I blathering about? This:-

Italians apparently believe that green coffee beans will remain in perfect condition for 18 months;

Roasted beans for 18 weeks;

And ground beans for 18 minutes.

That’s the Rule of 18. I have a feeling that there was more to the first version I saw, but Google is silent on the matter, mainly because the Rule of 18 is something I made up – I have no idea what it’s really called, or even if it has a name at all.

In my kitchen, beans** are coffee within 2 or 3 minutes of being ground, with a crèma the colour of an oiled and burnished hazelnut shell with gilded highlights, and the volatile aromatics have had little chance to dissipate. I buy beans, roasted just before they’re posted, in small quantities (3 x 250g packs), so there’s a fast turnover, and store them in CO2, in the fridge. Works for me.

**The grinder’s delivery chute is swept and blown clear (with a small brush and a photographic blower, the gleanings added to the rest), so all but a tiny amount of the 16g of beans that goes in, comes out again, minimising the carry-over of stale grounds to the next cup. You can never eliminate that entirely, short of dismantling the burrs each time, but you can reduce to a point at which it doesn’t matter.

And finally, as I reported at the time, the Gaggia portafilter basket** I bought for my Classic didn’t fit, and had to be modified. I was told this was the fault of Phillips, who now own the company, and who had been buggering about with the components. That now seems not to have been the case.

**Last item (at time of writing), on this page.

As I was finding I needed to use more beans, ground increasingly fine so they were, naturally, getting increasingly fluffy (fluffy is good), and wouldn’t fit the Gaggia basket, I bought a high-quality IMS double basket which holds up to 22g, compared to the 14g capacity of the Gaggia basket. Highly recommended – when you get a Classic you also get, whether you want it or not, Gaggia’s crèma-enhancing gizmo which, as far as I can tell, does nothing useful at all.** Don’t do as I did, go straight for the IMS basket – you won’t regret it.

**The ridge moulded into Gaggia baskets, into which the retaining spring locates, is totally unnecessary and, in the case of the basket I bought, wasn’t even properly circular, and it was that which mainly accounted for the bad fit. It also made it impossible to knock out the used puck – it had to be pried out with a spoon.

The IMS basket, though, is smooth and polished, without the ridge, but is still held perfectly securely by the spring, and knocking out the used puck is now very easy. There’s a downside – the IMS’s holes are bigger than the Gaggia’s, and allow rather more gritty fines into the cup but, as problems go, it’s pretty minor.