How does a chapatti puff? 

Indian Flat Bread, as it may be well known in the West, is locally known as chapatti or a roti in India. It is an age old practise of eating a soft – soft chapatti topped with loads of ghee with a Sabzi of one’s own choice. Be it Bhindi, karela, dal makhni, paneer butter masala, or any dal, chapatti is the best and healthiest option to team it up with.

And yes, all of us try our best to puff it up while we roast it directly on the gas burner so that it’s soft and gives a one of its kind mouth – feel. But we all fail and then learn and then finally rise with a proper puffed roti after several trials. But ever wondered why and how does it rise or puff so beautifully?

Here’s the answer.

Chapatti is made of atta that’s been kneaded into a dough with water salt and a little oil. Some people may add a little curd as well to make it softer and some may use milk instead of water. But what happens in the process?

1. Atta is made up of proteins called gliadin and glutenin. On becoming wet, these two proteins combine to form a protein called gluten which is responsible for this puffing. It’s a binding agent and provides the necessary structure to the chapatti. During kneading, when gluten becomes elastic and sticky, it forms a network of structures. Also, kneading causes the air to be trapped within these structures. So the more you knead, more the air trapped. But, do not knead too much. Or else, these gluten strands may break and give you failed puffed chapattis.

2. Atta also contains carbohydrates, specially starch which is responsible for the structure and volume of the chapatti. It co – works with gluten to provide the typical chapatti structure.

3. The use of milk or curd, add to the fat content of the dough. The role of fats is to tenderize the dough and give a soft chapatti. As mentioned earlier, leavening results in a soft chapatti, curd is another example of the leavening agent. The favourable bacteria in curd ferment it to produce carbon dioxide, which contributes to the air present in the puffed chapatti.

4. When you roll out the chapatti, make sure all sides are even. Otherwise the air trapped inside does not get uniformly heated and so the chapatti does not puff properly.

5. During roasting, steam is generated from the existing water content of the dough. This results in expansion of the air molecules trapped inside the rolled chapatti and hence we see the risen or puffed chapattis. Have you noticed the steam that escapes the chapatti in case you accidentally pierce the chapatti?? It is this air and steam that causes expansion of the chapatti.

Steam is a way to leaven the food product. Leavening leads to a voluminous and a soft product. And hence chapatti is leavened Majorly through the use of steam mechanism.

Easy isn’t it?

But not as much. The degree of kneading is a crucial step on getting a proper puffed chapatti. So next time analyse whether have u under kneaded or over kneaded the dough.

So next time when u make a chapatti and are wondering why is it not puffing, you got to see your kneading styles, the amount of water, curd or milk you added and the way you have rolled out your chapatti.

All the best!!


Science behind Dhokla 

Have you ever wondered why is there this particular texture of the dhokla? 
Or have you wondered what makes the dhokla rise? Of course the soda or eno fruit salt that you add to it, but how does it function?  

Have you ever wondered why are there holes in between the dhokla strands that you see?  

Here I’m going answer these questions, which would help you find the science behind each and every recipe that you cook and will help you to master them. 

Dhoklas are made of besan(roasted Bengal gram flour), sour curd/buttermilk, and eno fruit salt / baking soda. Each ingredient contributes itself to play a role in making the final dhokla that we see as an end result. 

1. Besan : besan is the protein source in the dhokla. Proteins when heated along with water (in this case buttermilk contains the required water content) starts to swell and therefore increases the mobility of dry protein content. This is why we get the texture and the mouthfeel that we get in the dhokla. Besan also has a binding property because of which it binds to the flavours and gives a characteristic flavour and aroma of dhokla. 

2. Sour Buttermilk : The catch here is the word sour, which indicates that the curd from which the buttermilk is made has already undergone enough fermention to release carbon dioxide by the lactobacillus bulgaricus and streptococcus thermophilus bacteria. This leads to aeration or leavening resulting in a fluffy, well risen dhokla. Secondly, buttermilk has some portions of the lipids / fats which act like an emulsifying agent and emulsifies the besan molecules to make a homogeneous mixture, thereby giving a smooth mouthfeel. 

3. Eno fruit salt or Baking soda : either of these ingredients may be used but both if these contain sodium carbonate, which when combined with the acidic components present in curd or buttermilk and reacts with some acids such as (cream of tartar) tartaric acids. On heating, these two components react together to produce carbon dioxide molecules which is trapped between the besan molecules and causes the dhokla to rise and give a volume to it. 

I’m giving an example of the reaction between sodium bicarbonate and cream of tartar but a similar reaction occurs with other acids present in the curd/buttermilk used to prepare dhokla. 

Tartaric acid + sodium bicarbonate → sodium tartrate + carbon dioxide + water 

C4H6O6 + 2 NaHCO3 → Na2C4H4O6 + 2 CO2 + 2 H2O

The more gas produced, the greater is the volume of the dhokla and the lighter is the product. But however you cannot use too much of it, or else the dhokla will taste bitter. The holes that you See in between the dhokla structure is because of this carbon dioxide that was trapped during the cooking. 

So here is the entire science behind the making of dhokla and the most importantly the science behind rising of the dhokla. 

I have not attached a recipe here since that will be available on a variety of websites and I would only be adding to the already existing information.. 

But now You know what is to be blamed in case something goes wrong in your recipe, or what is to be done to improve it. 

All the best! Visit this page for more science behind cooking various recipes.