A Quick Coffee Break

I know that I promised an explanation of what I meant in the last post by truly sustainable energy, and I still owe you guys that. But I wanted to take a quick break from environmental talk to discuss something of great importance to me: coffee. Everyday on the way to work, I stop by Dunkin’ Donuts to pick up a small iced coffee dark roast with cream and sugar. I’m there frequently enough that the employees have begun to reckon a pattern in my order (which basically doesn’t change). Some people aren’t coffee drinkers at all, and neither was I until I started college. The class that broke me was MSE 220. Don’t get me wrong, it was one of the best classes I’ve ever taken. It’s just that a dark, warm classroom was not conducive to my concentration as much as my nodding off.

Fig. 1: The usual Dunkin' Donuts morning coffee (orig.)

So let’s back up this post with a bit of content: coffee’s main active ingredient, as I’m sure you know, is caffeine. This relatively small organic molecule is the most widely consumed psychoactive drug and makes an appearance in many foodstuffs, especially in beverages. As a drug with dopamine-producing properties, it can be a source of addiction, though the symptoms of withdrawal are much lighter than those of controlled substances. The caffeine content for coffee, tea and soda types can be found here if you’re interested.

Fig. 2: Caffeine and adenosine molecules (University of Texas at Austin)

Caffeine works by competitively binding with adenosine receptors on neurons and is therefore deemed a receptor antagonist of all adenosine receptor types (A1, A2A, A2B and A3) [1]. Adenosine is a central nervous system neuromodulator that binds to receptors on neurons, slowing neuronal activity, dilating blood vessels and causing sleepiness [2]. I’m not good at tracking signaling pathways, but information on the adenosine pathway can be found here. When caffeine binds to the adenosine receptor, adenosine can no longer bind to slow neuronal activity and sleepiness is defeated. The increased neuronal activity caused by caffeine also induces the pituitary gland to secrete adrenaline and institute a state of “fight or flight” activity, another way caffeine energizes the sleepy world round [3].

Besides caffeine, there is other chemistry going on in coffee as well. A morning coffee is a good source of antioxidants (good for reasons mentioned in A Bit on That Shampoo Vitamin) and has been identified as the number one source of antioxidants in America, followed by black tea [1]. Coffee also has a nice hearty flavor, especially with my dark roast coffee, that comes from caramelization and Maillard processes (discussed back in Party Science, Part 3: The Tasty Grub) as well as the subtle bitterness of caffeine. And there you have it, a small cup of coffee science.

I’m going to try posting more photos that I take myself, but I’m not particularly trained in photography and only have my phone camera for the moment. Regardless, let me know what you think of the photos and if you have any photography tips I’d love to hear them. Anything helps!