I'm just getting into the coffee world, and I'm assaulted with words such as latte, espresso, etc. What are the basic differences between coffee preparations like espresso, cappuccino, and latte? Is the difference a matter of coffee-to-milk ratio or are there other aspects involved such as bitterness, acidity, caffeine amount, and serving size?
I'm going to assume that you've had an espresso. It's a small-cup of coffee extracted under very high pressure. It's delicious by itself and some like to add sugar.
So, what is a latte? Take a shot of espresso and add steamed milk
What is a cappuccino? Take a shot of espresso and add steam milk.
So, what's the difference between a latte and a cappuccino? Are they the same thing?
No. (Unless you're in a really bad diner in which case you shouldn't be ordering lattes there.)
There are several differences between a latte and a cappuccino.
One is the ratio of milk to espresso. A cappuccino is 1-1 milk to espresso and the latte is 2-1 milk to espresso.
Another difference is that the milk is treated differently. In a latte the milk is heated as opposed to being frothed. In a cappuccino the milk is frothed (converted into a microfoam) to about double it's original volume. (If you've ever heated or foamed milk you'll have noticed how the milk changes state as it's being heated.)
Finally the way the milk and espresso are combined is different. In a latte the heated milk and espresso are poured together into a serving cup. Whatever microfoam might have been created while heating the milk is then poured over the top. In a cappuccino the frothed microfoam is poured over the espresso.
It gets more involved than this but I'll let others answer those questions.
I am answering here as it applies to Italy, elsewhere it can be different.
Cappuccino in Italian means little cappuccio, which in turn means little cap. It is a milk-and-coffee drink with a peculiar topping: a milk foam obtained with steam. You might ask to add also some chocolate powder. Apart from the taste, the powder filling the foam pore gives a pleasant look to the drink. When travelling abroad, I see this as a standard feature, but here it is on request.
The steam is produced from a pump part of quite a large coffee machine, which is the standard equipment of any Italian bar. Because of the high pressure involved it is normally not possible to produce a cappuccino at home, at least not using a standard stove. Anyway nowadays they are selling cut down versions of the bar machine, which can produce bar-like cappuccinos (and coffee) even at home.
Temperature is crucial for cappuccino. Hot temperature is necessary to produce the foam, but a too hot cappuccino will hurt your tongue. Contrary to a hot cup of tea, where you can wait for it to become colder, here when the hot goes away also the foam does, so what you drink is not a cappuccino anymore.
Espresso means express, as you might guess. It is a coffee made with the big machine I mentioned above. Contrary to the coffee made at home on the stove, with the so called moka machine, this machine can make a good coffee instantly. That anyway requires this appliance to be already setup (with proper pressure and temperature levels), which takes time but it is done only once, in the morning, when the bar opens. it might help observing that breakfast is almost inexistent in Italy, as it consists for many of a fast and frugal espresso or cappuccino with a croissant, taken standing still at the bar before commuting to you workplace. So speed in brewing pays.
Besides Italian approach to coffee as a drink is radically different. For what I have seen, in the rest of the world the coffee is drunk in mugs similar to those used for the tea (I am thinking to American coffee for example); here the size of a coffee cup is extremely small and this is because the drink is concentrated. To brew the coffee like this you need water at high pressure and high temperature forced through a tier of coffee by the coffee machine.
Big espresso machines found in bars are ideal, given their power, to obtain this and generally their output is considered better than moka coffee made at home.
Note that contrary to cappuccino, here the higher the temperature the better the taste. To make it drinkable bars use special cups very thick. The final results is that you don't hurt your lips when you drink, also the volume of liquid going through your mouth is less, and you don't burn your tongue.
I have read that the total caffeine in an American coffee is higher, anyway the sensation that you have with an espresso is like you are taking something stronger and we even amplify this effect by drinking it fast, often in one shot.
Given the high temperature and pressure, if one does not make the espresso daily, it is very easy to make it burned, producing something that is bitter and distasteful. I have seen many used to American coffee (big cups), disliking espresso and vice versa. Anyway, before deciding that the strong taste of espresso is not for you, make sure you have tasted a professionally made one.
As I said before, there are now home espresso machines, which are also easy to operate.
Latte is short for latte macchiato, stained milk. The stain is the a little quantity of coffee.
Strange as it may seem, in Italy the word espresso is a sort of foreigner word not used at all. Perhaps it was in 1800, when the espresso was invented, but now we just say: "A coffee, please".
There was already a question here that someone answered with an image showing drink recipes, but it's worth noting that these are loose definitions and that the actual recipe can vary based on the cafe you examine.
Starting with an espresso base and going from smaller to larger ratios of milk: Espresso < Macchiato < cappuccino < latte
Espresso: Full coffee flavor Macchiato: 1:1 ratio, flavor leans towards coffee cappuccino: 1:3 ratio, flavor should be balanced latte: 7-? ozs of milk, mostly milk flavor
Acidity and bitterness will depend on your coffee, but as noted above coffee flavor dissipates when you add more milk.
In Australia we have different differences between a latte and a cappucino. They're both the same size and made the same way (some say a cappuccino should be a little bit frothier), but they're both served in different styles of cups (this is important but I don't really know why) and the cappuccino has chocolate sprinkles on top.
Here's a latte glass:
And here's a cappuccino cup: