Why Americano Is Bitter and How the 1:2 Espresso Ratio Fits In

Espresso dialing comes down to three parameters: dose, brew ratio and the interplay of time and grind. The 1:2 ratio, such as 18g of grounds yielding 36ml of liquid, works as a starting point because it balances extraction. A shot that tastes sharp and sour is usually underextracted, and this is often why americano is bitter or sour in the cup rather than smooth.

Dose and ratio rarely change much; grind is what needs repeated fine-tuning. Aim for a roughly 30-second extraction window, then judge the grind by taste. When flavor goes off, correct it through dose and yield first rather than water temperature or pressure. An americano coffee taste bitter enough to notice often traces back to a grind that ran too coarse or too fast.

Many friends who are just getting into espresso often run into this confusion: they follow the popular online formula of 18g of grounds extracting 36ml of liquid, and the coffee ends up tasting sharp and sour, clearly underextracted—yet they don't know whether to adjust the water temperature, pressure, water volume, or grind. In fact, dialing in espresso isn't complicated; you just need to focus on three core parameters: dose, brew ratio, and the interplay between time and grind. Dose and ratio usually don't vary much—what really needs fine-tuning again and again is the grind size. Drawing on Front Street's hands-on experience, this article explains why 1:2 is considered the golden ratio for espresso, how to use the roughly 30-second extraction time window to judge whether your grind is right, and how to make fine corrections through dose and yield when the flavor goes off—helping beginners quickly build a clear, workable approach to espresso extraction.

Even if you apply the wildly popular online extraction formula—say, "18 grams of grounds yielding 36 milliliters of espresso"—the final shot can still end up underextracted because the extraction time is too short, hitting your palate as sharp and sour. Then you come asking Front Street: in this situation, should I adjust the water temperature, the pressure, the water volume, or the grind?

This is a problem many beginners run into. Tutorials online are all over the place, and the scattered bits of knowledge people pick up only leave them unsure where to start adjusting. So today Front Street is going to talk about how to dial in a relatively standard espresso.

Adjusting espresso is actually very simple—just grasp three parameters: dose, ratio, and time with grind. As for water temperature, pressure, and the portafilter basket, Front Street doesn't recommend that beginners touch them right away. For one thing, they're a hassle to adjust; for another, there's not much need—just leave them at factory settings. Once you're familiar with the logic of espresso extraction down the road, it won't be too late to look into them. (You might even get up to speed faster)

Among these three parameters, dose and ratio hardly ever change much—what we're mainly adjusting is the grind. Espresso extraction requires leaving some headspace between the puck and the group head, so each basket has a recommended dose range; just use the amount of grounds within that recommended range. The same logic applies to the brew ratio.

If you only drink espresso, or dilute it with water to make an Americano or long black, then the brew ratio doesn't really matter. But if you want to use that espresso to make milk drinks like a latte, flat white, or cappuccino, Front Street suggests not adjusting the yield too much—keep it around 1:2. Why? It comes down to the concentration of the espresso.

Whether in Front Street's "Why 1:2 Is the Golden Espresso Brew Ratio" or in the article "What's the Difference Between Ristretto, Normale, and Lungo," we've mentioned that the brew ratio determines the coffee's concentration. Assuming the extraction yield stays the same, the larger the ratio, the higher the coffee's concentration, and vice versa.

When we use espresso as a base to make various specialty coffee drinks, it's best for the espresso to have a relatively high concentration. Because if the concentration is too low, the resulting drink will taste noticeably watery—thin, hollow, and weak, with the overall mouthfeel diluted.

1:2 is a brew ratio that lets espresso maintain a relatively high concentration, and many espresso drinks use espresso at this ratio as their base. So if you need espresso to make milk coffee, the brew ratio during extraction should ideally be around 1:2. (Not fixed—small adjustments are fine)

Once the ratio and dose are fixed, the only thing left to adjust is the grind size. Grind size affects the particle size of the coffee grounds, and particle size in turn determines the resistance of the puck, which then affects the extraction time.

In other words, we can adjust the grind size based on time. If the extraction is faster than expected, grind finer; if it's slower than expected, grind coarser. But then the question arises again: exactly how many seconds should this time be?

Front Street recommends keeping it around 30 seconds—that is, in the 26-to-34-second range. This time window, combined with a 1:2 brew ratio, gives the coffee a relatively suitable extraction yield and makes it less prone to problems like over- or under-extraction. After that, you just fine-tune based on the coffee's flavor.

Take Front Street as an example: the basket we use has a recommended dose of 20 grams, so we use 20 grams of grounds; at a 1:2 brew ratio, the yield is 40 milliliters, with the time set at 30 seconds.

If it takes only 10 seconds to extract 40 milliliters of espresso, then you need to grind the coffee finer. On Front Street's grinder, each notch of adjustment changes the extraction time by 3 to 5 seconds. Since we're 15 seconds off the target time, here Front Street needs to adjust the grind finer (toward smaller numbers) by 4 to 6 notches.

Once the grind is adjusted, grind and extract again. If the time falls within the target range, that's naturally best. If not, you can also taste it to see whether it performs well. If it tastes good, then such parameters are acceptable too—there's no need to rigidly insist that the parameters must fall within the target range.

If the time falls within the target range but the flavor isn't quite pleasing, we can judge from the coffee's taste whether it's over- or under-extracted, and then make subtle adjustments to the dose and yield.

For example, if the coffee is bitter, it may be over-extracted; in that case, reduce the yield a little to lower the extraction yield, then see whether the extracted coffee still carries over-extracted notes. If it's under-extracted, you can raise the extraction yield by slightly increasing the dose or the liquid weight.

That's the beginner's guide to making espresso—very simple~ If you still have questions, feel free to leave a comment below or message us in the backend, and let's discuss solutions together~ - END -

The above content is compiled by CoffeeHunters, a coffee news website.