Tag: Coffee

The simple answer: about 15 grams of ground coffee per 8-ounce (240ml) cup of brewed coffee. This works out to roughly two heaping tablespoons, though weighing is far more accurate.

Why the answer depends on what you mean by cup

An American cup measure is 240ml. A coffee mug is often 350-400ml. A small espresso cup is 60-80ml. Different vessels need different amounts. The ratio stays roughly constant; the absolute amount scales.

Brewing math made simple

Use a 1:16 ratio as your starting point. That means 1 gram of coffee for every 16 grams of water. For one 240ml cup: 240 divided by 16 equals 15 grams of coffee. For a 350ml mug: about 22 grams. For a 12-cup drip machine making 1.5 liters: about 95 grams.

Why the math is approximate

Some water is absorbed by the grounds rather than ending up in your cup. Each gram of coffee retains about 2 grams of water. So if you brew with 240g of water and 15g of coffee, you will end up with roughly 210g (or 210ml) of liquid in the cup. Plan accordingly if precise serving size matters.

Adjustments by taste

If your coffee tastes weak at 1:16, push to 1:15 or even 1:14. If it tastes too intense, try 1:17. The ratio is a starting point, not a rule. Your beans, your brewing method, and your preferences all shift the right number for you.

You can pour hot water over used coffee grounds and get a brown liquid out the other end. Whether you can call that liquid coffee is a different question.

What happens chemically

The first brew extracts most of the desirable compounds: sugars, oils, balanced acids, and aromatic flavors. By the time the first cup is done, roughly 18 to 22 percent of the coffee mass has dissolved, which is the sweet spot for taste. What remains is largely cellulose and the harsher, less-soluble compounds that did not come out the first time.

A second brew pulls those harsher compounds without the sweetness to balance them. The result is bitter, thin, and astringent.

The exception: cascara and steep extensions

Some drinkers extend the steep on a single brew rather than doing two. With a French press, leaving the grounds in for 6 to 8 minutes instead of 4 will extract more, though you risk bitterness. This is different from a true second brew because the grounds are still doing their first-pass extraction.

Practical alternatives

If you are trying to stretch your coffee budget, the better moves are to grind slightly finer (extracts more from the same amount), brew at a stronger ratio (1:14 instead of 1:16), or buy in slightly larger quantities to capture small bulk discounts.

If you genuinely want to reuse grounds, they have a much better second life as garden compost, deodorizer for the fridge, or scrub for greasy pans. They are excellent at all three. Just not at making coffee.