Milk is an important part of Australian coffee drinking culture. Around 90% of coffee drinks in Australia are served with milk. Why do certain types of milk froth better than others, and what does the type of milk you use matter? We hope the following bits of information help clarify the nuances of milk in coffee preparation and how to find the best milk for your purpose.
What Is the Best Milk for Frothing?
Full cream is the best for frothing as it has a good level of protein (3-4g per 100ml is ideal). Protein is needed in order to create protein skeletons in the milk which we know as ‘microfoam’ (glossy, wet-paint look to the milk).
Soy milk can be good to texture too as it has a higher protein percentage than other milk alternatives. Along with it having a good fat percentage too (more than 2g per 100ml is ideal). The difficulty with soy milk though is that it has the tendency to curdle when it reacts with the oils in the coffee.
Does the Type of Milk You Use Matter?
Yes. The more fat a milk has, the creamier and thicker in texture it will be. The more protein a milk has, the more elasticity the milk will have and will hold its structure (i.e., the foam and milk won’t separate as quickly making it easier to pour latte art).
Why does milk sometimes refuse to froth?
If the milk has fat and protein in it, it will froth. That’s because in order to create micro-foam (glossy, wet-paint look to your milk), you need protein. Fat is also important as it gives weight to milk.
Additionally, if the milk does not have enough fat and protein, the manufacturer can add vegetable gums in order to make the milk thicker.
Vegetable gums are a type of thickener or thickening agent used to improve the viscosity of a food product. They work by partially absorbing the liquid and therefore making the liquid thicker.
Optimal temperature for steaming and frothing milk
We perceive milk to be the sweetest in-between 60-70 degrees. This is because as we heat the milk, we break the sugars in the milk down into smaller particles which is easier for our palates to pick up. If we go over 70 degrees though, the protein enzymes begin to burn which will cause the milk to split quickly. Along with giving it a sour/off taste.
Why are some milks different from others?
All milks differ in their protein and fat content and will therefore have different characteristics when frothing. An additional reason as to why one milk differs from another, can be due to their ingredients list. The addition of thickening agents such as vegetable gum, will increase the viscosity of a milk.
How to Froth Milk
See our guide on how to steam perfect milk at home here
What is Barista Milk?
Usually if a milk brand labels one of their milks as ‘Barista Milk’ it means that it has more protein and fat than their regular line of milk. Making the milk creamier in texture when you froth it.
What is the best way to froth milk at home
There are two ways you can froth milk:
- Using home espresso machine – we already have a blog that covers this
- Using a French press – heat your milk to between 60-70 degrees Celsius. Then pour the milk into a French press and continue to raise the handle up (bring the filter part to the top of the glass) and then plunge down again (pushing the filter part to the bottom of the glass). As you continue to plunge, air molecules will be added to the heated milk and will form a foamy texture.
What exactly happens to your milk when you froth it
When you froth your milk, 3 main reactions occur:
1. As you begin to heat your milk, the fats within the milk begin to thin out and become a similar consistency to the crema of an espresso shot. That’s why it’s easier to do latte art with full cream milk rather than skinny milk. As skinny milk has less fat, the foam in the milk has a harder time staying above the surface of the crema and falls underneath
2. As you heat the milk, the sugars within the milk break down into smaller particles which is easier for your palate to pick up. If you go over 70 degrees though, the protein enzymes begin to burn which will cause the milk to have a sour/off taste. Along with resulting in the milk split from the foam which will be difficult to pour any latte art.
3. As you add air to your milk, little enzymes within the milk attach themselves to the air molecules that you are adding. When these enzymes connect with the air molecules, they form a protein skeleton which is known as microfoam. The trick with these enzymes though, is that they deactivate after 37 degrees Celsius. Meaning that you’ll need to add in all your air within the first few seconds of steaming your milk. Another indicator is to stop adding the air in when the jug becomes the same temperature as your hand (as the average body temperature is 37 degrees Celsius).
Now that you have a greater understanding of milk and you’re wanting to take your coffee skills and knowledge to the next level; check out some of our other blog articles or email us at firstname.lastname@example.org to find out the vast range of courses we offer to help you on your coffee journey.