We love to talk about coffee, don’t we? Well, we love our favorite crutch, and its faithful ability to get us through all the otherwise groggy mornings. Recently, I’ve been spending time on some of the internet coffee forums, learning things that (as a person whose habit runs well over four decades) – I was surprised I didn’t know. It was a good break from the usual forums-to–visit list, and the much more droll postings I put on my https://programmingmiscellany.wordpress.com site.
Did you ever notice that reheated coffee is just terrible? Really, it’s awful, and thanks to a recent coffee forum visit, I have an answer to share with you. As it turns out, it’s NOT the reheating that causes the taste to spoil. It’s the cooling. According to an article on coffeechemistry.org, there are phenols in the coffee (cafeic and quinic organic acids) – that engender a change in the coffee’s composition as it cools. At the end of the cooling-off period, the coffee is effectively ruined.
Now, I suppose there is some method to prevent this – because some of the canned cold coffees appeal to my taste buds. But, for the home brewer, and his coffee carafe – the cool-down is killer. Note that I’m interpreting what’s on the site within my layman’s perception of chemistry. My assumption/extrapolation maybe is something they’d take time to argue against. You can decide for yourself …
Here’s a link to the site:
Have you ever tried expresso grind beans for making a cup of regular coffee? My experience is that the finely ground coffee makes a pretty good cup, and it’s more intense even if it’s prepared using lesser amounts. I guess that we throw away most of the coffee when we use coarsely ground coffee, don’t we? If you think about a tiny chip of coarsely ground coffee, and the water-contact surface area it has, it’s intuitive to see that by cutting the little chip in half, you have more surface area, as what was hidden (inside the granule) is now exposed by the cut. The additional surface area (exposed to water) pulls more coffee into the brew. If you cut those two granules into four, then you expose that much more surface area. Expresso ground coffee is just coffee with its granules cut many times more often than the regular grind has been cut. So, you’re using more of the coffee, by saturating more surface area, and throwing away less of what could be extracted from the discarded grounds.
I guess there’s a downside to using the finely ground stuff. Oxygen and/or carbon dioxide contact with the granule’s surface is what degrades stored coffee (or so I have read). So, intuitively, finely ground (expresso ground) coffee will not last as long on the shelf. I must buy the expresso ground coffee in a bag, because my coffee grinder would be spewing smoke by the time it could pulverize the beans to that level 🙂
I suppose turkish coffee is about the same idea, with the beans being pulverized almost to the granularity of confectioner’s sugar. They don’t bother to filter the grounds, as so much of the coffee totally dissolves into the brew. I can see why they don’t use filters for that fine grind. The tiny granules clog up my paper filters in a hurry. It can take much too long (in the morning, when I really need it not to be slow) – to drain through the paper into the carafe! But, I guess there are certain oils that are best removed from the coffee, and so I use the filters with the expresso. Sometimes I smooth the bottom of the grounds bin with a spoon to speed things up.
There are coffee connoisseurs, and then there’s me. A coffee purist will not purchase bags of ground coffee from retail (groceries, etc) – because of the previously mentioned degradation via oxygen and carbon dioxide exposure. Deteriorated coffee produces carbon dioxide in the bag, and the gas exacerbates the destruction of the contents. Or so I’ve read. I’m picking the coffee trivia up here and there, and in between the real and the bogus “facts” I find on the net, I’m at least half right. Is that better than half wrong?
The purist might say that after a month or two on the shelf (if it’s ground) – it’s already started its trip downhill. Such folks buy freshly roasted beans, and grind it on demand. Truthfully, I’ve been buying coffee for over forty years, and am fine with the stuff on the shelf. I know it’s all been there more than two months 🙂