Bajra Papad – the Color Secret 

Okay so this somehow sounds boring… Bajra Papad??  Eeeuw… But no.. They taste really good.. And specially with the recipe that I’m going to provide here. 

Yes, since this is a novel recipe and I myself couldn’t find the recipe online (an authentic one that worked well), I’ll be attaching the recipe without which explaining the science behind it wouldn’t be given justice. 

So, bajra Papad Is made up of bajra flour and I have also added some rice flour to it for better consistency and taste. 


Preparation Time: 5mins 

Cooking Time: 5-6mins 

Post cooking Time: 10-15mins 

Drying Time: 4-5hrs (sun drying)

Yield: 50g (No. Of Papad depends on the size) 

With my size it yielded 15-20 papads. 


1+ 1/2cup (300ml)  water 

1/2 cup (100ml/60g) bajra (pearl millet)  flour 

1/2 cup (100ml/59~60g) rice flour 

5g Ginger – chilli paste (3:2)

1/2tsp salt(to taste) 

1tsp whole jeera (cumin seeds) 

1tsp ajwain (carom seeds) 

1tsp sodium bicarbonate 


1. Boil the water, add the spices (do not add the sodium bicarbonate)

2. After 1 min, mix the two flours and add to the above boiling mixture.

3. Continuously mix with a wooden ladle or spoon till thick consistency, and it becomes dough like, and leaves the sides. No flour lumps should be present. 

4. Transfer it to another plate, add Sodium bicarbonate, mix a little and let it cool till your skin can tolerate the temperature. 

5. Knead it properly to form a smooth dough. Divide into equal sized balls. 

6. Roll these balls with oil as and when required (so that the dough does not stick during rolling and tear off) Roll in between plastic sheets or ohp sheets. (make sure that the plastic sheets do not give wrinkle marks to the rolled out papads or else they will crack during drying.)

7. In case you are bad at rolling(like I am), you can use a round cookie cutter of desired size to give it proper shape. The thickness should be 0.1mm – 0.2mm. Not too thick not too thin. 

8. Spread the papads on a cotton cloth and sun dry till they are hard. Collect and store in air tight containers. 

9. These can be microwaved / roasted / fried. (I would always prefer microwaved, since they give u the original flavour of the Papad, plus its super healthy!! ) Serve with khichdi, rice, pulao, or anything u wish. You can have it as a snack too if it’s microwaved!!  

Okay, so now let’s come to the science behind all of this. 

1. Cooking of the flour and making a dough: As discussed in my earlier blog, the Cereal (rice and bajra together) gels with the water and forms a Gelatinized mixture when heated at temperetures above 80 degrees. Therefore it forms a soft dough when it cools as all the water added has been trapped between the starch granules present in the flours. 

2. Addition of sodium bicarbonate: This chemical is a leavening agent, so as a result it contributes to the softness and crispiness of the Papad. If u notice, when u add the sodium bicarb and leave for a while, and then again knead it, the dough has already risen and increases in size and volume and becomes a little softer and porous. 

Also, when we eat papads, they are not very hard nor too soft. It has a perfect blend of softness and hardness owing this property to this magic element. 

Remember I had asked you not to add soda during the boiling of water? Why did I do so?

Simplest scientific reason being, sodium bicarbonate solution has a pH of 7, which is alkaline. And when pearl millet or bajra is added to this alkaline water,  it changes color to grey as reported by this particular study  by R. D. Reichert in 1979. Therefore it is very important to understand when sodium bicarbonate should be added in different preparations. when sodium bicarbonate is added in water, the color of the papads  is brownish grey and when the soda is added after removing from the fire, the color remains green. Which is more appealing without compromising the effect of soda on the Papad. 

3. Drying: Drying is a process where the moisture content of the food is reduced to 10-12%. It is different from dehydration, since in dehydration, the moisture is reduced to less than 3%. So when we dry, the moisture content of the Papad gets evaporated and we get the hard texture of the Papad. 

Yes I know that sun drying is the most unhygienic way of drying the papads, but at this level this can be done inside homes to make it more hygienic. But if u have access to a tray dryer, you are most welcome to use it for drying the papads. 

I’m also a nutritionist, and so I would recommend healthiest of ways to eat.. You can trust me with this though!  

So, here are some tips to make these papads more healthy: 

1. You can use sprouted bajra flour instead of normal bajra flour. 

2. You can add spinach / carrot / beetroot puree or any other vegetable puree that you want. Just make sure to adjust the amount of water added. 

3. Garnish the papads with salad and coriander leaves and have it as a starter instead of an accompaniment. 

So this is all that you need to know about bajra papads. All the best for your endeavour with making good scientific papads!! 


The Science Behind Khandvi

Today, we consider the western foods to be great and yummy, and most preferred, but when it comes to the knowledge and science that goes behind the making of the traditional Indian foods, one might just fall for it all over again. Our grand parents and great grandparents might not have been as educated as we are, but they had way more knowledge and understanding of the foods they cooked everyday than we know of eating everyday. 

Today we shall discuss about khandvi, which is a native dish of Gujarat, India, where people love to eat the roasted gram flour rolls, spiced and flavoured. In Maharashtra, this dish is commonly known as suralichi vadi air patuli. 

Again, I would like to mention that I will not be providing any recipe as that is available on the web on numerous websites. Here we will talk about the uncommon. 

Khandvi is made up of a mixture of besan or roasted Bengal gram flour and buttermilk. Everyone knows that the cooking of this mixture is the most tricky and difficult part of the entire recipe. So here’s why. 

The roasted gram flour is rich in its protein content. This is enhanced by the use of buttermilk, which is also high in proteins. When dissolved in water, these protein molecules absorb moisture  and swell. The volume increases and the viscosity or the resistance to flow decreases. That’s when we say that the batter is thickening. While making khandvi, the thickness of the batter is very important. Because if it becomes too thin, it will be difficult to roll, and if it becomes too thin, it will b too difficult to evenly spread on to the flat surface. It will then form undesirable lumps. 

But what happens to the proteins? 

The proteins in the solution form, or a sol form gets converted to a progel state by denaturation and polymerisation. 

1. Denaturation: it is the phenomenon in which the original structure of the proteins is hampered or changed to a new structure in the presence of various factors like change of temperature, pH, moisture, etc. 

2. Polymerisation: It is the process in which the bond between the two amino acids break due to the reaction with water. 

So as a result, the gram flour mixture thickens in the presence of moisture and difference of temperature. 
Now, when the gram flour mixture is in the progel state, the functional groups (hydrogen bonding and hydrophobic groups) become exposed so that it facilitates formation of the protein network in the second stage. 
Second stage? 

Yes, there is a second stage as well. When this mixture is cooled to room temperature or refrigeration temperature, there is a decrease in the thermal kinetic energy which promotes formation of stable non covalent bonds among the above exposed groups which results in the formation of a gel. So what you see on the flat surface, after you have spread the batter and cooled it, is a gel. Only when a proper gel is formed, you will be able to make rolls out of it. 

The sol state to progel state is a non reversible reaction which progel to gel state is a reversible reaction. On re-heating the gelled batter, it will melt back to the progel state as it must have been experienced when you re-heat some curries made of gram flour. This is because hydrogen bonds are the major contributors to the network formation. 

Next time you can try this by keeping aside some part of the heated mixture and then re-heating it when cooled. Experience for yourself!!

Also, we have used curd in the form of buttermilk. Why curd and nothing else

Curds are an excellent source of leavening agent. Leavening agents are basically substances which lead to rising of the batters and doughs and making it soft and voluminous. This leads to soft gels of the proteins and which is why you have that smooth texture and soft “melt in the mouth” feel of the khandvi. The moisture in the form of buttermilk will keep the khandvi moist and prevent drying and hardening of the khandvi.  Too much or too little of this important ingredient will result in the failure of the recipe. So beware!! 

Here’s all about science behind khandvi. Try the recipes by keeping these points on mind and I’m sure you will never go wrong. You would know how to improve next. 

Keep reading for more recipe sciences. Enjoy scientific cooking. After all, cooking is  an art as well  as a science!! 

Mango Pickles – a need for taste or preservation for mangoes?

Day in and day out, each Indian adds flavour to his meals by including pickles, commonly known as achaar. But, ages back, was the pickle made to add variety to the meals or as a simple method of preserving fruits and vegetables??

In the era of old age, when people did not have access across the globe, the Indian farmers felt the need to preserve the extra stock of mangoes that grew in India. It came as a preservation method to avoid wastage of food for efficient food management.

Also, being a seasonal fruit, the discovery of preservation methods, gave the added advantage of availability of the fruit throughout the year, in the off seasons.

Mangoes are an Indian favourite and is known as the king of fruits! And we Indians convert this fruit into various other forms and enjoy it’s lavishness throughout the year! But now, let’s have a look at the different forms of pickled mangoes and the science behind each.

Today, since pickling has become a business to earn extra profits, Special varieties of mangoes are picked specially for the purpose of pickling. Usually all the mango pickles are made of raw mangoes since they prove to be tangy and sour to taste and make very good pickles.

1. Sookhi kaeri (dried mango pickle): The technique used here for preservation is sun drying. The pieces of mango is sun dried for several days till it is completely devoid of moisture and feels a little hard, dry and the edges feel crispy. This reduces the water activity in the mango and hence the micro organisms fail to thrive in that environment. Also, the enzymes present in the mango itself requires a certain amount of moisture or water activity for it to function. As a result the mango is preserved for several months. It is then spiced with salt, turmeric, whole jeera, etc. to make it tasty!

2. Murabba and Khaman (both are varieties of sweet mango pickle): another technique used to preserve mangoes is to use sugar. When sugar is added to the mangoes, in the form of a sugar syrup, the sugar being hygroscopic, competes with the enzymes and micro organisms for the moisture. As a result, the organisms and enzymes cannot function according to their roles and hence, sugar acts as a preservative.
Due to high osmotic pressure, the water from the organisms is drawn out resulting in its death. As a result the pathogenic or spoilage bacteria are unable to survive in that osmotic pressure. Hence the mangoes are preserved. However, Indians being sweet lovers, find these forms of pickling extremely tempting. They pair it with theplas, parathas, etc., and enjoy it’s flavour.

3. Methia kaeri (fenugreek mangoes): The bitter phenolic compounds present in the fenugreek seeds are probably responsible for the preservative effect. However, studies need to be carried out with regards to this. Hence, nothing can be said for sure.

But a sure reason is use of oils in all the other mango pickles. Be it mixed mango pickle or fenugreek or woth any other ingredient. The oil cut down the air supply, and therefore the oxygen supply to the spoilage and pathogenic bacteria. So they fail to thrive. This is also the reason why our grandmothers used to fill a layer of oil over the pickles in the bottles and jars. Today as we become health conscious and start to add less and less oil to pickles, have you noticed that the topmost layer of the pickle often seems to be covered with fungi?


Simply because that’s where they receive their nutrition plus air to thrive and spoil the pickle.

So next time when you ask your moms to add less oil, think again. You might just be wasting a lot of her efforts in the long run!

4. Sour Mango pickle: we all know that sour would mean the presence of excess acids. Now these acids are definitely not too harmful for us, but they are definitely harmful for the toxic bacteria and fungi. These thrive in an optimum pH of around 6.5-7 which is almost neutral. While the pH of these pickles is less than 4.6 which is acidic. The raw mangoes and lime, naturally lower the pH of the food product that kills the micro organisms.

5. Salt: The very 1st step in almost all pickle recipes is addition of salt to the raw mangoes, or immersing them into a brine solution (a mixture of water and salt)!


Because salt absorbs water from the foods and makes it too dry. This prevents the growth of microbes in the food and hence preserves the food.

Here I’ve listed various ways of preserving Mangoes and the science that stands firm behind it. However there are more ways and more secrets behind the pickles. Keep reading my blog for them.

So, next when you are wondering about how can you extend the pleasure of eating mangoes, follow these principles. Your taste buds will surely thank you for it!!

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!!

The Upma Science 

Early morning when you run late for office or you have to prepare a quick breakfast for your husband or family, what do you make?
Probably an upma? Why? 

Simply because it’s easy and fast.. But ever wondered why does it become a solid – like mass when it cools? Or have you ever noticed that even though the entire upma is coalesced together, every grain of upma retains its individual existence?? 

Yes, that happens… And yes, there is science behind this simple dish prepared by Indians all over the world.. 

Upma is cooked by basic 3 ingredients.  Semolina or suji,  ghee and water. The recipe shall be available everywhere on the web, and so I’d only focus on the science involved in the recipe. 

1. ROASTING : The first crucial step in making upma is roasting the Suji or semolina. Why? Suji is roasted with a little amount of fat so that each grain is separated and coated with fat. This is done to avoid lumping when the water is added. Also,  in this way,  each starch(suji) grain will Be exposed to uniform hear and water and hence will swell independently. This is why at end of the entire cooking process and with so much of stirring, the suji grain remins as it is. 

2. COOKING : When suji is roasted evenly, water is added and cooked by stirring continuously. A process called GELATINIZATION takes place. When the temperature reaches 60-71 degrees Celsius, the starch starts to Gelatinize and at a temperature of 88-92 degrees Celsius, this process is completed. 

In this process,  the kinetic energy of the hot water breaks the bonds between starch molecules and hence the crystalline structure of the starch is lost. Also, it loses its birefringence property (a property due to which, when a polarised light passes through the non – hydrated starch grain, it gets deflected in two directions). 
Water then forms hydrogen bonds with the starch grains and penetrates into it. As a result, the grain swells up. As the grains are completely swollen, the amylose of the starch leaches out and it becomes viscous. This results in a thick paste like consistency of the upma. This is what happens in the process of Gelatinization. So when u see any mixture of starch and water (Sol) become think on heating, be rest assured that the process of Gelatinization is taking place..  

3. COOLING : Now comes the actual question of why does the above viscous Sol become a solid mass on cooking?  Here’s the answer.  

On cooling, the Gelatinization mixture undergoes a process called GELATION. On cooling, the heat energy is released. A hydrogen bond is formed between the amylose moities that were earlier leached out of the grain. This causes the water molecules to get entrapped between these bonds and form a three dimensional structure. So this structure formation is responsible for the solid mass of upma. 

RETROGRADATION is another process that takes place when upma is refrigerated. What happens is, due to the hydrogen bonding between the amylose moities, the lost crystallinity and birefringence re-appears and we get a gritty texture of upma when it cools. This process may lead to SYNERSIS or oozing out of the water from the upma undesirably. Specially when the food is subjected to continuous freeze – thaw cycles.

So yes, this was all you need to know about the upma Science… Next time you cook upma, make sure you notice the changes and store your upma accordingly. 

And yes,  you can always apply these same principles to any starch that you are cooking. 

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.