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When you visit India or go to an Indian restaurant you are bound to find dishes that contain paneer. Since there are a lot of vegetarians in India, there is often a paneer version of meat dishes, such as butter paneer (instead of butter chicken). But it definitely isn’t always a replacement. Paneer is a real staple in Indian cuisine. So what is paneer?
Paneer is a fresh cheese made from just milk and an acid (e.g. lemon juice). It can be as fresh as only a few minutes old before being added to a dish! It is white, quite firm and crumbly. So how does it work you’re asking? That’s what we’ll dive into here, by the end you should know how to make paneer and understand why it’s made the way it is!
There are a lot of different types of cheese around the world. Soft vs. hard, packed full of flavour or more neutral ones. Nevertheless, the basis of cheese making is always the same. You start with milk that you curdle by either adding an acid or an enzyme.
When you curdle cheese you force certain proteins (the caseins) to group together into clusters, curds. These curds will also contain the fat of the milk. You then remove these curds from the rest of the milk and you end up with cheese + whey (the remaining liquid).
Using an acid for curdling milk
When you make paneer you curdle the milk by heating it up and adding an acid such as lemon juice. So what happens during this process?
Remember that milk consists for a big part of water as well as some sugar (lactose), proteins and fats. In your store bought pasteurized milk, fat floats around the milk in the form of very small droplets.
The proteins themselves are made up of two groups: whey & casein proteins. The caseins from same clusters, called micelles, which float around in the milk as well. These micelles are very small, so you won’t see them individually in milk. When you make cheese you want these micelles to grow and cluster together to form a curd. We know that you can do this by adding something acidic to the milk.
Why spoiled milk contains lumps
Ever wondered why your spoiled milk that has turned sour also contains little lumps in the milk? This is the same process occurring! Milk turns sour because of spoilage bacteria and this sourness causes the caseins to cluster, forming these lumps.
Cheese vs. yogurt
When you make yogurt you also turn the milk sour. So you may wonder: why don’t you end up with cheese but with yogurt? When you make yogurt the bacteria in the yogurt actually turn the milk sour over a longer period of time. Because of this slower process, the proteins reorganize themselves slightly less abrupt and you end up with softer gels.
Making paneer – the science
To make paneer you only need two ingredients: milk & something sour. That something sour often is lemon or lime juice or vinegar. However, just adding the sour ingredient to the milk won’t make it curdle immediately, you need to heat up the milk for the process to go nice and fast.
The high heat of the milk will make all the molecules inside the milk move a lot faster. Because of this, as soon as the acid is added, the different casein micelles will find one another a lot faster. An added benefit is that boiling the milk will kill bacteria in the milk that might otherwise cause spoilage of the cheese.
Once the milk is boiling hot you can add the acid to the milk. Once you’ve added enough acid (to bring the pH down to the value where the casein micelles start to cluster) you will immediately see the milk change.
Why milk changes colour when making paneer
In the image above you can see that the curdled milk is no longer white. This is because the milk doesn’t actually contain a white pigment (like white paint would). Instead, milk is white because of the way it scatters all colours of light. The fat droplets and casein micelles that we discussed earlier are the ones that cause this. Once you start curdling the milk both the fat droplets and the casein micelles sits in the curds. As a result, the rest of the liquid will not reflect the light in the same way anymore and thus won’t be white anymore, instead, it will be more translucent and slightly yellowish.
Whole vs skimmed milk for paneer
When you form the curds from milk the curds will contain all the fat and casein that is present in the milk. If you use skimmed milk there is no fat in the milk. As a result, you will end up with less paneer. Also, this paneer will be drier, the fat (as with most cheeses) makes the paneer softer and more tender.
If you want a super delicious paneer you should try making it from water buffalo milk. This milk contains more fat and as a rest gives a great indulgent paneer!
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Filtering & pressing
Once you’ve formed the curds & the whey it is time to separate the two. This is easy now, just use a piece of cloth (cheese cloth is easiest) and pour the mixture on. The curds will not pass through whereas the liquid whey (that doesn’t contain any particles) will! It is a simple physical separation based on particle size.
Once you’ve got your curds separated you can press them under some weights. Pressing the curds together will push out even more moisture and make the curds firmer. However, you can skip this step and use the paneer immediately, although at this point t will not be firm enough to slice it blocks, it’s easier to crumble it in pieces apart.
Paneer is a very versatile cheese. Once you’ve made it you can eat it cold, on a sandwich, or hot in a wide variety of dishes. The firmer the paneer, the easier it is to fry it in some oil. Frying it will dry out the cheese a little further, but the additional crispiness and brown pieces will be worth it. In India you will find paneer in a lot of curries and sauces, keeping the paneer nice and moist.
How long to store paneer for
If you make your own paneer you will have to keep in mind that you cannot store it for that long unless you’ve worked very cleanly. Yeasts and moulds sit all around in the air around us and if you don’t sterilize your cheese cloth and equipment, they will start growing on your paneer almost immediately. This is not a problem if you only want to store the paneer for a few days at most. Just store it in the fridge and you will be fine. However, it makes it unsuitable for longer storage.
Store bought paneer that is vacuum packed for instance has been made in such a way as to delay growth of micro organisms. As a result you can often store this longer than your homemade version.