I can’t live without my cup of Joe, but as I read through the book Uncommon Grounds, I find out more and more about this mysterious beverage.

Like how a goat herder in Ethiopia discovered it when his goats went missing. He found them jumping around, buzzed off the red coffee berries. Fast forward a few centuries, and we have coffee in every store on the planet. But what exactly is in a cup?

It all starts with a coffee berry. Too bad what we really want is nestled deep inside. Two seeds surrounded by a silver skin that’s hard to remove.

Acording to Al Rayan, there are many grades of roasting you can get from a bean. (Side note, when Americans first got hold of these beans, we liked them green. Then we’d roast them right before making a cup.)

The bitterness associated with coffee comes from the roasting. Think about licking a singed hunk of wood. Yeah, not so great.

The bitterness comes from O-caffeoylquinic acids, present in raw coffee beans. A light or medium roast dehydrates the acids to create various lactones and a pleasant bitterness that most coffee lovers adore. Keep roasting, and the lactones break apart to from 4-vinylcatechol, which goes through some more chemical steps to create compounds that give a harsh bitter that lingers on the tongue.

Once roasted, coffee beans can stay fresh for months. Once ground, however, and you have only about two weeks to make your coffee (key here, grind your own). But even after being brewed, the chemistry of coffee changes. Lactones become free acids, dropping the pH from between 5 and 5.2 down to a 4.6. This shifts the acidity from a green bean level to that of a tomato.

The longer you keep your coffee hot, the more sour and bitter it will taste.

Although many studies have found antioxidant qualities in coffee, you could be canceling these out by adding cream or sugar. A study by a fella named Crozier showed that adding cream to strawberries slowed the absorption of antioxidants. So if you want the best health benefits from java, drink it black.