Science of making Indian paneer

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!

Making cheese

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.

All about milk in one page

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.

The curds that have been sieved apart from the whey, ready to be pressed.

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.

milk + vinegar experiment-1
Just milk is white and completely liquid. Adding a little acid to the milk will lead to the formation of a few curds, but the milk still looks white. Once you’ve added a enough acid (in this case vinegar) the colour of the milk will change drastically and you can see curds floating around. Adding more acid will not change the appearance further, but it can tighten up the curds and make them drier in the end. Sometimes this is what you want, it depends on your application.

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!

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.

Pressing down the paneer curds

Using paneer

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.

saag paneer
Saag paneer – a spinach sauce with browned pieces of paneer inside.

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.

Yield: Enough paneer for 2-4 people

Indian paneer

Indian paneer

A basic, very simple recipe for making your own paneer. Apart from the ingredients you will need a clean cloth (cheese cloth works best).

Prep Time: 15 minutes
Total Time: 15 minutes

Ingredients

  • 1 liter milk
  • 2 tbsp lemon juice / lime juice / vinegar (if using vinegar, start with 1,5 tbsp, it's a little stronger)

Instructions

  1. Bring the milk to the boil.
  2. Take it off the heat but do not let it cool down.
  3. Add the acid and mix through well. The milk should start curdling pretty much right away. You will see white curds forming and the liquid becoming more transparant/yellow. If the liquid stays white you have to add some additional acid. Add it in steps of 1 tsp to prevent from overdosing.
  4. Once the liquid (also called whey) has become clear, pour the mixture over a cheese cloth.
  5. Fold the curds in a cheese cloth and place below a heavy pan or stone to press out the remainder of moisture.
  6. Wait at least 30 minutes before using if you want a firm paneer, you can easily leave it up to two hours, it will just become a little firmer.
  7. Once the paneer is ready you can store in the fridge for max a few days.

4 comments

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  • Hi Julie,

    Your post made me think of how paneer made from heavy cream will taste/feel since heavy cream has a higher fat content – thoughts? Also, do you think if there’ll be a difference between paneer made from ultra-pasteurized milk vs pasteurized vs raw?

    PS: I came across your blog today and thoroughly enjoyed reading through many posts. I am on a mission for perfecting ice creams and Hello my name is ice cream is one of my favorite ice cream books! One of the issues I’ve been having with ice cream making is sometimes my ice creams have a buttery mouthfeel, which I know is because of overchurning, even though the total time those ice creams were churning in the ice cream maker were pretty much same as other times when the buttery feel didn’t happen. I have also noticed difference in the buttery mouth feel depending on which brand I was using. Somewhere in there you wrote not to boil heavy cream – I am going to keep that in mind.

    • Hi Preethi,

      So glad to hear that you’re enjoying the blog!

      I like your thoughts on using heavy cream. However, heavy cream contains a lot less casein and so will not curdle as well. Also, there should be enough casein to casein and capture all the fat. In the case of cream, even if there was the same amount of casein there is very likely to be too much fat present for all of it to be caught up in the casein clusters!

  • Thank you so much! I was persuaded to try making cheese and thought I’d have a better chance at success if I studied the science first.

    Your explanations are excellent and I’m much more comfortable with moving forward now.

    J’y vais a la cuisine!

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