Cheese is one of the oldest foodstuffs in the world, dating back thousands of years to Mesopotamia, Anatolia, and Asia. Exposure to the sun caused the milk ancient farmers produced to separate, hurdle, and harden into the most rudimentary forms of cheese.
We have come a long way since then, both in terms of cheese production as well as means to keep milk from separating and curdling. After all, for as lovely as cheese is, if that isn’t the goal and you want smooth, tasty dairy instead, the last thing you want is for milk to separate and start to turn chunky or start to suffer from bacterial buildup.
Thankfully, if you are preparing milk, be it from cows or, in this case, coconuts, there are plenty of ways to prevent premature and unwanted separation and curdling.
A Closer Look at Coconut Milk Separation
One of the most important things to keep in mind when considering coconut milk in particular is that, as much as we often think of it as one single substance, it is actually a concoction of coconut oil and protein mixed with water.
As a result, it should come as no surprise that these two distinct ingredients naturally separate into two layers.
In traditional milk, this separation would be between the fluid at the bottom (whey) and the separated squishy proto-cheese curds. With coconut oil, the separation is similar, with the oil and protein congealing into a solid cream at the top with a watery substance at the bottom.
Note that the color of the cream can vary somewhat, from snowy white to more of a greyish hue. The liquid at the bottom will also vary, with some mixtures producing a smooth mixture and others a lumpier one with more individual flecks.
Part of that variation is due to the fact that the FDA doesn’t regulate “coconut milk” as uniformly as it does dairy milk, thus resulting in different ratios of its ingredients and therefore everything from extra smooth to super lumpy samples.
Meanwhile, the actual process of separation can likewise vary – and it isn’t always pretty. Sure, cheesemaking is one potential outcome of separation, but spoiled milk can also cause separation, leading to bacterial infestations producing more lactic acid, increased clumping, and rancid odor.
Needless to say, you won’t be making any cheddar or gouda out of that.
On the other hand, there are other, more particular ways coconut milk can curdle as well.
For example, coconut milk can also have freshness problems once you open the container. Trying to reuse leftover coconut milk means having to deal with the increased lumpiness that is bound to result from having opened the container and thus exposed it to the external forces that start the separation and curdling process.
It isn’t just exposure to heat that can cause coconut milk to separate, but too much time in the refrigerator as well. Prolonged refrigeration produces a hardened layer of cream, especially if you leave it in there for a period longer than five days.
What You Can Do to Prevent it
Now that we have a better idea about how separation occurs in milk in general and coconut milk in particular, let’s take a look at a few potential ways of preventing it from occurring.
Let’s start with the latter issue of refrigeration first. Since the big issue here is coconut milk hardening and producing lumps as a result of the cold, the natural solution is to try and acclimatize it.
Take the coconut milk out for a while and let it naturally reach room temperature before you place it back in the fridge. Once it has cooled down and reached the temperature you want, shake it a few times to help mix the materials back up.
Doing this should return the milk to its semi-lumpy or even smooth consistency.
Sticking with that methodology, you can also try using a blender to re-emulsify the milk.
Once again, what you are trying to do here is restore your coconut milk to the consistency it was before it started to harden. If the problem is materials starting to clump together too much, a blender should bust those clumps apart with ease, returning your coconut milk to a nice easily-drinkable and servable mixture.
Then there is the predicament posed by heat and the more “traditional” curdling and separating process. As with regular milk, you’ll want to avoid prolonged exposure to heat and leaving your milk out too long in general so as to ensure that it does not begin to attract bacteria or begin to curdle.
Be aware that the shelf life of coconut milk is on the shorter side compared to regular milk. Ideally, you want to use your coconut milk no more than four to six days after you have brought it home.
Can you keep and use your coconut milk after that period?
Sure, and we’ll talk about how to do so most effectively in a moment.
But will it be as fresh as if you had used it within six days?
Probably not – again, unless you follow the following tips to a tee and are a bit lucky with how your coconut milk holds up.
To attack several of these problems at once, you’ll want to make sure that you are storing your coconut milk in the best manner possible, both before and after you have opened it. The best way to do this is to make sure that the lid is closed not just slightly but completely.
The last thing you want is for air to be able to get in there and start the separation process.
For the best chance of preserving your coconut milk long-term, you’ll want to cover it with not just the lid it came with, but some aluminum foil as well, thereby locking in the freshness as much as possible.
Separation and curdling is a millennia-old natural part of the milk-to-cheese process in dairy, but to keep coconut milk fresh, you’ll want to do what you can to forestall it with the tips mentioned above.
Sarah is the founder of Baking Kneads, LLC, a blog sharing guides, tips, and recipes for those learning how to bake. Growing up as the daughter of a baker, she spent much of her childhood learning the basics in a local bakery.