For many coffee lovers, milk is simply part of the drink and they don’t even consider drinking a coffee without it - espresso shots and black filter coffee isn’t on the menu. Milk has been paired with coffee for almost as long as coffee has been around, but what does it do to the drink and why add milk to coffee?
Join us, as we explore the role of milk in our favourite beverage, its benefits, and how to get the best results when using milk in your coffee so you can enjoy barista-quality drinks at home.
Why we add milk to coffee
Where there are ground beans, milk isn’t far behind. While some countries, such as Ethiopia and Japan, still prefer to consume their coffee untainted by the sweet creaminess of milk, Western coffee culture and the delicious taste of milk-based coffee drinks is becoming more accepted there, too. Whether it’s with traditional dairy milk or one of the many plant-based substitutes, milk is king.
But why?
There are three main reasons for the global love affair with milk-based coffee drinks:
- Sweetness
- Texture
- Cooling
The last is the most obvious - putting milk into your hot coffee lowers the temperature and allows you to enjoy it straight away, but that could be replaced with a little patience, what about the other two?
Milk for sweetness
Cow’s milk contains lactose, a natural sugar, while plant-based milk substitutes often have sugar added. Bringing this sweetness to the drink can temper some of the bitterness of pure coffee which, for many coffee lovers, is the difference between a drink that’s just a bit too tart, and one that’s soft and delicious.
It’s a big plus that the milk balances bitterness and acidity in coffee. Softening the sharpness of darker roasts makes the drink more accessible and is a big part of its worldwide dominance. Not everyone has the same tastes and adding milk is a more subtle and gentle way to get that sweet offset than simply spooning sugar into the cup.
There’s a counter argument here though, often used by espresso aficionados, that the sweetness that comes from adding milk overpowers some of the subtle tastes of the coffee bean - and they have a point, especially when you have a top-quality grinder such as a Niche Zero or Duo. With a consistent grind set to the optimum coarseness, the key flavours from the bean are released perfectly, allowing you to enjoy the coffee without additives, or to use milk delicately to complement the flavours rather than cover up poorly extracted bitterness.
Adding milk becomes, quite literally, a matter of taste.
Milk for texture
When you add milk to coffee, you change the texture of the drink, making it richer and creamier. This can have a huge impact on your enjoyment of the drink, as it’ll feel softer and more velvety on your tongue.
Of course, it’s not always just a case of pouring milk from the jug into the coffee. When you introduce milk to the drink for texture, milk is often steamed to further develop that thick texture, with microfoam at the far edge of the steaming spectrum offering an extremely dainty touch to the coffee that helps develop flavour and overall textural engagement.
In short, milk makes the coffee feel good as well as taste great.
Cows or plants - milk and its substitutes
Milk doesn’t just mean dairy. Though cow’s milk is the traditional accompaniment to coffee, there are plenty of alternatives for those who are lactose intolerant, vegan, or simply prefer a different taste and texture.
- Whole dairy milk - When it comes to both texture and sweetness, whole milk is superior to the other alternatives. Though it’s a downside for anyone seeking a healthier drink, the higher fat content is exactly what brings the sumptuous feel and texture to the cup - plus, whole milk has a naturally sweeter taste. Whole milk also holds its shape better when steamed for foaming, making it the best for look, especially when considering latte art. Unless asked to do otherwise, most baristas will default to whole dairy milk for these reasons.
- Semi-skimmed dairy milk - A slightly healthier alternative to whole milk, semi-skimmed is a reasonable option. It is thinner than full fat milk, however, leading to a slightly less creamy texture and lower levels of sweetness.
- Oat milk - The top choice for non-dairy milks, oat milk provides a good plant-based option. The ‘barista’ versions of oat milk contain added fats and proteins to make them better for foaming and closer to dairy whole milk. Barista edition oat milk is creamy, foams well, and produces a smooth texture. It is naturally sweet and complements the coffee nicely, though it can mask some of the more delicate notes in some coffees.
- Soy milk - Again, it’s best to choose the ‘barista’ version of soy milk to ensure a good response to steaming. Soy milk can taste a little earthy, and reacts badly to being overheated, so care is needed with temperature. Soy is best with darker roasts to avoid overpowering the natural coffee flavours.
- Almond milk - The nuttiness of almond milk can add a desirable secondary taste to the coffee, which enhances the flavour for many. Purists, however, may considered this a deal-breaking downside, especially with light roasts. Almond milk doesn’t foam as well as the other alternatives, making it a poor option for latte art enthusiasts.
- Coconut milk - Coconut has a strong flavour that will come through into the drink, though it is a taste that works well with many coffees. For those who enjoy that additional flavour, coconut milk can work well. It steams well and has a thicker texture that makes it an enjoyable mouthful.
- Other plant-based milks - Options such as rice, cashew, and others tend to work poorly as a dairy substitute for coffee, often separating or being too watery to enhance with the texture. Generally, these are better avoided if barista-quality results are wanted.
How to steam milk for coffee
In espresso based coffees, milk is rarely as simple as just ‘pour and stir’. Steaming the milk improves texture, adding a smoothness that milk straight from the jug won’t equal, while also avoiding chilling the drink. Drinks that use steamed milk include:
- Latte - as the name suggests, lattes have a significant amount of steamed milk, with a layer of foam on top to give it that silky texture.
- Cappuccino - three parts espresso, steamed milk, and foam, a cappuccino has a very specific recipe that results in a smooth, milky drink with a lightly textured top.
- Flat white - with less milk than a latte, a flat white is aiming for a stronger taste that nonetheless enjoys the smooth texture that milk provides.
- Macchiato - coffee is core here, with just a touch of steamed milk or dollop of dense foam providing a velvety touch.
- Mocha - a rich taste thanks to the combined chocolate, a mocha is closest to a latte with creamy steamed milk and just a nod to foam.
- Cortado - a drink that’s half espresso and half steamed milk (no foam!), with the aim to simply offset the coffee with a little soft sweetness.
- Getting your steamed milk right is not as simple as it might look and may need a little practice to get right - it’s all part of the enjoyment of home coffee creation! You want to aim for an ideal temperature of 60 to 65°C. This is where the milk will be hot but not scalding and the natural sweetness will be at its peak. Once you pass 70°C, your milk will become burnt, which means the proteins will break down, the sweetness will drop away, and it may even start to taste a little eggy.
- It’s worth investing in a milk thermometer to get the temperature right and give yourself the best chance of perfecting your steamed milk coffees.
Some steaming hints
Making foam and microfoam
The difference between microfoam and thick foam is in the size of the bubbles. Thick foam is better for cappuccinos where a firm top is preferred, while microfoam works well as the cap on a latte, giving it the silky, velvety texture you’re after.
Experimenting with your steaming is essential to get the microfoam you’re after - and it’s all to do with how much you submerge the steam wand. When the wand is close to the surface of the milk in your jug, it will produce more air which leads to bigger bubbles in the foam - too deep and you’ll do little more than heat the milk.
For microfoam, you will need to introduce the right amount of air early on and then submerge the steam wand to texture the milk and add heat, remembering to angle the jug to 45° to help create the perfect vortex.
It’s worth noting that every machine and steam wand nozzle is slightly different and it will need practice as you adjust your technique to get the level of foam you’re looking for.
Problems frothing milk
If you’ve got your technique right but the milk’s not frothing, then it could be down to the ingredients. Plant-based milks that aren’t ‘barista’ version will often lack the concentration of proteins needed to get the foam. Sadly, there is a pay off between choosing many non-dairy milks and the quality of the foam.
Another reason could be down to the equipment. A poor-quality wand will produce consistently substandard results, while one that’s not properly cleaned can block. Sometimes it’s not you!
Pairing with perfect espresso
Steaming can sometimes go wrong when the milk interacts with the coffee, especially if the drink is too oily, as the oils will quickly collapse the bubbles in the foam.
When it comes down to it, you really want a good espresso to go with your top-notch foam! Select good quality beans, grind fresh with a Niche Zero or Duo, and brew with consistency.
Milk in non-espresso coffees
Milk is beloved in all forms of coffee, not just espresso, but it’s worth noting that while steamed milk can be used, it may feel out of place paired with a pourover, Fresh press, or moka pot coffee.
In these situations, many cover lovers turn to cream, which offers a thicker and sweeter companion that brings a whole new level of flavour and texture enhancing to the drinks.
Like everything else coffee though, never forget to experiment and find the combination of coffee and milk that suits your tastes. It’s all about personal enjoyment - don’t let anyone tell you otherwise!
Getting the most from milk
Whether you’re a latte-lover or simply like to add a splash of milk to colour and cool your filter coffee, understanding the role milk plays gives you control over your cup. Remember though, for the very best coffee, you need to start with a quality grind.
When your coffee routine begins with beautifully-roasted beans expertly ground with a Niche Zero or Niche Duo, the foundations are all in place for a sumptuous, velvety cup. Just add milk.