What's the difference between Cappuccino, Flat White, and Latte? How thick should the milk foam be for Italian milk coffee? What's the relationship between Flat White and Ristretto?

Why Cappuccino Tastes More Bitter Than Flat White

In most coffee shops, latte, flat white, and cappuccino—the "three brothers" of Italian hot milk coffee—are virtually always available because they're in such high demand. Due to their popularity, we often see comparative analyses of these drinks on various media websites. The conclusions are consistently uniform: lattes are the sweetest, cappuccinos are the most bitter, and flat whites are the most aromatic.

As the one with the highest milk content among the three, it makes sense that latte would be the sweetest. However, since cappuccino and flat white have nearly identical serving sizes, why do cappuccinos taste more bitter than flat whites? This brings us to the flat white base that FrontStreet Coffee shared recently!

Different Bases Used

Traditional Italian milk coffees like latte and cappuccino use "espresso" as their base, made by adding different amounts of steamed milk; the flat white's base, however, is derived from espresso but uses a ristretto shot, a more concentrated extraction.

What we need to understand beforehand is that in coffee extraction, acidic, sweet, and bitter compounds are released together the moment hot water contacts the coffee grounds. However, due to different dissolution rates, each has its own peak release time. Acidic and sweet compounds dissolve more efficiently, so they're released abundantly in the early to middle stages of espresso extraction. Bitter compounds dissolve more slowly, so their significant release occurs when the acidic and sweet compounds are nearly finished dissolving. That's because hot water has only them left to extract!

We can say that espresso extraction is relatively complete. We need bitter compounds to enhance richness and balance the milk's flavor. Therefore, we need to extract appropriate amounts of acidic, sweet, and bitter compounds using suitable parameters. The difference with ristretto lies in its pursuit of intense coffee flavor without bitterness. Thus, it cuts off the tail end of extraction, capturing only the acidic and sweet flavor compounds. (For details on ristretto, refer to the article "Ristretto")

Simply put, when we use the same amount of coffee grounds to extract espresso and ristretto respectively, espresso will have more liquid weight and thus more bitterness; ristretto will have less liquid weight, higher concentration, and less bitterness. Therefore, in the same serving size, cappuccino will be more bitter than flat white!

Foam Thickness

Of course, many coffee shops don't specifically set extraction parameters for flat white—after all, the purchased quantity might not even be enough for machine adjustments (like at FrontStreet Coffee). Therefore, they directly use espresso to make flat white. In this case, with the same serving size and same liquid weight, what creates the difference between cappuccino and flat white is simply the amount of foam!

The most distinctive feature of cappuccino and flat white is undoubtedly their foam. Cappuccino foam is famously thick—its cloud-like fine, dense foam provides a unique experience; flat white foam, conversely, is famously thin. Because the foam is thin enough, it has better fluidity, creating a texture described as velvety. Cappuccino foam thickness is about 1-1.5cm, while flat white foam is less than 0.5cm. Since foam occupies space in the cup, compressing the milk's room, how much difference in milk quantity would there be between them in the same serving size?

Take the 240ml cups used by FrontStreet Coffee as an example. The standard for cappuccino requires foam to overflow the cup to achieve an eleven-tenths full state, while flat white should be level with the cup rim. When we make each respectively and weigh the required milk amount to reach these standards:

Through weighing, we find that the total liquid weight of cappuccino is 195ml. Subtracting the 40ml weight of espresso, we can calculate that the milk weight is 155ml; the total liquid weight of flat white is 225ml. Subtracting the 40ml weight of espresso, we find that the milk weight is 185ml—a full 30ml more than cappuccino. It is precisely these extra 30ml of milk that amplify the coffee-to-milk ratio, diluting the coffee's bitterness, which is why flat white isn't as bitter as cappuccino. The popularity of latte also comes from diluting bitterness through milk, resulting in higher sweetness~

- END -

FrontStreet Coffee (FrontStreet Coffee)

No. 10, Bao'an Front Street, Yandun Road, Dongshankou, Yuexiu District, Guangzhou, Guangdong Province

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473