Coffee Talk Part 4: Brewing

If you’ve been reading this series, you’ve seen us take a journey through the world of coffee from the origin, to the growing, to the processing, roasting and grinding. Now, it’s time to get cooking.

The ground coffee can be prepared in two ways: brewing and espressing. Brewing is clearly the most common and the easiest and most forgiving method. Espressing requires high-pressure steam, finely ground coffee and tightly packed grounds to work correctly. Therefore, espressing should be left to trained persons.

The difference is the quantity and type of compounds that are removed from the grounds. Brewing will remove only the water-soluble compounds, while espressing removes oil-soluble compounds as well. Properly brewed coffee should be a shade of brown ranging from light to near black. Also it should be transparent, not muddy. Espresso should be a light, creamy caramel color, thick and opaque. Under the creaminess is a dark, concentrated liquid.

The key to all coffee making, no matter what kind or method, is water temperature. Too cool and it won’t remove the valuable flavor compounds, thus wasting the coffee. The most common mistake in making coffee is not having water that’s hot enough.

We normally think of Espresso makers as large, steamy, locomotive-looking contraptions that whistle and hiss. These use steam shot through tightly packed grounds to make the drink. But there’s also a vacuum pot commonly used in many homes, especially Italian homes, that produces a similar product on an ordinary stove top.

Brewing can break down into several different methods. Boiling was common until the 1930s when filtration methods like percolating became popular. Steeping is common for single portions or cups, and is still popular for high-end coffees.

There much more to learn about brewing a good cup of coffee, which we will cover in the next post.