In the image below there is a quote from Dassana’s veg recipes blog regarding the use of Eno (especially citric acid) in Dhoklas . She felt that citric acid had an edge over lemon juice. I am a long time fan of her recipes and usually her instincts are spot on. I dug into the food science and I think I have the answer!
But first, what is ENO and why is it called fruit salt?
James Crossley Eno, a British pharmacist invented ENO in 1852 and like many food entrepreneurs of that time – Nestle, Maggi, Hershey’s, very creatively named the product after himself :). Eno is called as fruit salt. For the longest time, I could not figure out why it is called fruit salt. Is it sprinkled on fruits? Ummm…no!!
In the mid 18th century, there was a mad rush for natural spring water with dissolved carbonate and sulphate salts in them. The water was supposed to be healing. Even now, Epsom salt (Magnesium Sulphate) is sold as foot soak.
But why travel to France or exotic springs to get the special water, when you can create it at home? To recreate the salts, James Eno packaged a dry acid – (citric acid or tartaric) and a base – sodium bicarbonate (baking soda) together. Both these products in the presence of water (going back to basic chemistry) would create a fizz – due to CO2(how fun) and create a salt (sodium citrate, sodium tartarate) in the process.
Of course, back then, citric acid was actually extracted from fruits like lemon and oranges, and tartaric acid came from grapes. Hence the name “fruit salt.” Get it? – fruit for the citric acid and salt for the resultant salt. Of course, nowadays, there is no fruit needed to make citric acid. It can be made through chemical means or in large bio-fermentation tanks using the fungus Aspergillus niger.
ENO as a leavening agent
Over time, in India, where Eno got enormously popular, people figured out a clever trick – Use it as a leavening agent. I personally only like plain ENO and not the flavored packets with added flavors, colors; but you do you. It bubbles up immediately on contact with water. It works as a great leavener and here is why:
2 things happen immediately when ENO is added to a liquid:
- Vigorous immediate bubbling effect from CO2
- Creation of Sodium Citrate salt which works as an excellent emulsifier
The fact that Sodium Citrate is a great emulsifier is a well known fact in the food industry for almost 100 years. Ever heard of James Kraft? Yes, the same person of Kraft cheese fame. In 1915, he ran a cheese shop in Chicago and got fed up keeping up with the shelf life of cheese and dealing with odd knobs and ends of cheeses. So, he decided to pasteurize the cheeses.
Killed all the active microbes in the process, but I don’t blame him.
If I ran a cheese shop and the cheese around me were spoiling at different times, I would probably do the same thing. Anyway, when he heated the cheeses, guess what happened? The fats and the proteins would separate and a greasy pool would form around the cheese. To make the fats play nice, he added – wait for it – sodium citrate and it continues to be used to this day.
Is Emulsifier a bad word?
I am not going to get into the details of whether commercial emulsifiers are good or bad for you. The word emulsifier in itself has no negative or positive correlation. They just hold hydrophobic and hyrophilic parts together. They don’t let the fat globules gang up and pool together.
You use natural emulsifiers all the time in the kitchen. For example, you used the phospholipids in egg yolk to make creamy ice creams that does not allow the fats and water to separate in the freezer, Similarly Casein particles in milk and butter act as emulsifier. The French make butter sauces and we make add cubes of butter at the end of Paneer butter masala or Pav bhaji to basically emulsify sauces. But, more on that later…
Why does Dokhla even need an emulsifier?
Every Dhokla recipe will require you to add 1 tsp or more of oil. Here’s a visual representation to show what Sodium Citrate is good at. I added ENO to a cup in which oil and water were mixed.
First there is an expected fizz from the reaction. But secondly – Do you see what the sodium citrate did? It broke those fats into itty-bitty pieces and distributed it throughout the solution.
This is the creaminess that Dassana was referring to. Below is another pan in which I added oil, water and ENO and heated it. Heating further redistributed the fat molecules.
This concept works on western cakes too. Check out my favorite food science person Adam Ragusea’s video on “why boxed cake is better than homemade.” He boils it down to emulsifiers among other food science reasons. Before you pooh pooh it, I once went on and on about how moist a cake that a sweet neighbor gave us. I was like “share the recipe”, “you are so good at this”, “this cake is the best.” I wish I dialed it down a bit for her sake. She sheepishly told us it was boxed cake. I adore her and hope she forgives my over-enthusiastic nature.
Why not lemon juice?
Yes, lemon juice has citric acid; which makes up 5-6% of the juice. But it also has Malic acid and ascorbic acid and many other organic compounds. So, while lemon brings a complex flavor profile; the vigor with which it can release CO2 and emulsifying salts is not as much as pure citric acid.
And that’s a good place to end for now. I can add baking powder discussion later if you are interested. Hey, I am active now on Instagram! Check out me talking about this topic in a 1:30 min reel here:
Also, I do Youtube Shorts now, or rather I am trying….Here’s the link. Follow me there as I stumble through video editing apps…Either way, bye for now and see you on the next post.
I make my own Eno, or fruit salt. When I saw the price of it, and I found out that I have the ingredients – citric acid and baking soda – I made it, and it works fine! 3 parts soda to 2 parts citric acid -most formulas call for a small amount of salt, maybe 8-10%, but I’m not sure what that does. The fact that it forms an emulsifier, in addition to leavening makes sense, as those Indian dishes traditionally made with it are eggless, and egg yolks are the emulsifiers in most desserts we normally make here.
When I make the fruit salt I don’t make a lot, as humidity can activate the powders, in contact with each other. I also keep one of those silica gel packets in the jar, to absorb any humidity that gets in, when opened.
Hi David, that’s a clever idea to buy them separately and mix them yourself. I agree, the price sticker is definitely a shocker and priced more than it should be.
Also, you made a clever association of the fact that Indians dishes typically avoid eggs. I didn’t quite think of it that way until you mentioned it. Thank you for your idea and inputs, much appreciated!!
I have often wondered why they add egg into the dough of south Indian parotta dough.The quantity of egg added is so minimal like 1 egg per 1kg of flour that it is not enough to have any impact on the taste.Based on your logic it looks like the intent is to emulsify the oil+water mixture that is used to knead the dough.Oil needs to be uniformly distributed into the dough to get those paper thin membranes!
That seems entirely plausible…What a clever hypothesis, Anil! Thanks for sharing!