It's extremely hot and humid in Delhi. Not even a single leaf on the trees is moving. Two cousins, Riya and Arka, step out for a walk in the nearby park but return drenched in sweat. As they reach the gate, they spot an ice cream cart.
“In this heat, it’s pointless to waste energy walking, brother Arka. Didn’t I say I’d treat you to ice cream that day?” says Riya, pointing at the cart.
“You did say that in Chandni Chowk! I totally forgot. Let’s go.”
While ordering, Riya chooses a butterscotch cone, and Arka picks a candy. Seeing this, Riya asks, “Why did you go for that cheap candy?”
“Because I like it! Simple! Now tell me, what’s the difference between candy and ice cream?”
“Candy is like a hard rock, and ice cream is… well, ice cream, meaning it has cream.”
“Zero marks. Think a bit. Use your brain. Only a little kid would answer like that.”
“Exactly! My brain’s not working in this heat. You tell me instead. I’d rather enjoy my ice cream while listening.”
“You lazy thing. Anyway, look, this candy is hard because it contains frozen ice crystals just like the ice that forms in a freezer. The difference is that regular ice doesn’t contain sugar or milk. Candy contains both in the right amounts. And sugar is the key here. You know that if you mix salt or sugar in water, its ‘Himanko’ drops, right?”
“Oh no! What’s ‘Himanko’?” Riya exclaims.
“It’s the Bengali term for ‘freezing point.’ Don’t panic. Do you know that saltwater freezes at a lower temperature?”
“Yes, it does! I know that. It works with other salts too. But if you mix salt in ice cream… eww!”
“Right, but even mixing sugar lowers water’s freezing point. So, ice crystals form below zero degrees Celsius. But if you just mix milk, sugar, and flavor into water and stick it in the freezer, what you get won’t taste like this soft and delicious ice cream. The one you’re eating has evenly distributed ice crystals throughout. That’s what gives it that smooth, velvety texture.
“To make ice cream, first you have to whip milk, cream, and sugar really well, and then add flavoring. And by whipping, I mean churning the mixture vigorously in a machine. During this process, a lot of air gets incorporated into the mix. The resulting mixture is what scientists call a colloidal solution. Now, if you cool this mixture well below the freezing point, it becomes ice cream. This method causes small, fine ice crystals to form. Because of the air pockets, the mixture never becomes solid like a block of ice, it stays soft and creamy.”
Riya’s ice cream cone was almost finished. Chewing the hard end of the butterscotch cone, she asked,
"Exactly how much below zero is the temperature kept?"
"Definitely minus 20 degrees Celsius. Even if you bring ice cream from a shop, it should be stored in the freezer at around that temperature, otherwise it will melt."
“Then tell me a bit about ice candy,” Riya said, wiping her hands with a tissue as they started walking home.
“In candy, water is used instead of milk and cream. That’s why it doesn’t differ much from regular ice cubes. But various flavors and colors are used to make candies appealing. Like the one I had just now, the stick I just tossed into the dustbin, that was called mango candy, but you wouldn’t find even a trace of actual mango in it. Just mango flavor and aroma. In better-quality candies, they even mix a little milk. Tastes pretty good.”
“No wonder we see so many varieties of ice cream in the market, but not that many for candy. So, brother Arka, can you tell me when and where ice cream was invented?”
Photo credit – Kaveh Farrokh
Early 1800s, Naples, Italy – watercolor graphic art by Bartolomeo Pinelli (1781–1835), a street vendor who used to sell sherbet to children.
(Source: Borys Voznytskyi Lviv National Art Gallery)
Arka walked silently for a while, deep in thought, before replying,
"It’s a bit difficult to say where exactly ice cream was first invented, but experts believe that ice cream making probably began in either China or Iran. There are references to ice cream in texts that are over 3,000 years old. So it’s safe to say that people had been trying to make it long before that. In desert regions, to beat the heat, people began experimenting with frozen desserts. However, what we eat today as 'ice cream' wasn’t quite the same back then. It was more like what we would now call a ‘frozen dessert.’ In Iran, they called it sherbet. But that sherbet isn’t what we drink today. It was made by mixing chilled icy water and milk with floral nectar and such. How much cream it had—who knows!”
“I’ve heard that some shops in Chandni Chowk still serve such sherbet,” Riya commented.
“Of course they do. In a city built by the Mughals, that cultural trace is bound to remain. With this heat, I feel like going and having some of that sherbet right now!”
“We could even make it at home. Anyway, tell me one thing—back then there were no fridges, so where did people get ice?”
“Why, they’d bring down huge blocks of ice from the mountaintops!”
"Wouldn’t those melt on the way?"
Arka looked at Riya and laughed, "Looks like you need to brush up on your Class 12 science book again! People had figured out through experience that if you covered blocks of ice with sawdust or stacks of straw, they wouldn’t melt easily because wood and straw are ‘Aporibahi’."
Riya shouted, "What bahi? Don’t use such difficult Bengali words sometimes it just goes right over my head!"
“‘Aporibahi’ means ‘insulator.’ Since wood is an insulator, it does not conduct heat. With such a thick head, you want to study science?”
“I studied this in English. But it’s good I’m learning from you in Bengali now. Still, that doesn’t mean you can…”
“Why are you getting angry? Listen, you’ll be surprised to know—mixing salt with ice lowers its freezing point. And humans discovered this thousands of years ago! That’s why the practice of storing ice by mixing it with salt is very old. Once refrigerators were invented in the 20th century, that’s when the real ice cream revolution began. Since people could make and store it easily, Europe, especially Italy, started full-fledged experiments with ice cream. Before that, even in Europe, they had to haul blocks of ice from distant mountains.”
“Refrigerators were invented by Albert T. Marshall, right?”
“I’m not that good with trivia. I’ve always stayed away from quiz competitions. But no invention is truly the work of a single person. It takes the effort of many people before something becomes a full-fledged discovery. The one who finally gets the credit—his name ends up in the science books.”
Suddenly, a gust of wind blew up dust. Leaves began falling from the trees lining both sides of the road.
“Looks like a storm’s coming, Arka. Let’s hurry or we’ll get blown away,” Riya said.
Arka, running while holding Riya’s hand, said, “Yes, and maybe you’ll end up landing in a 4,000-year-old ice depot in ancient Iran!”
“Oh my goodness! They’ve found such things?”
Yakhchal (2nd image from the inside)
Yakhchal – where people stored ice all year round. Photo credit – Stony Brook
“Well, instead of scrolling your phone all day, you should look up some pictures online—places where people stored ice for the whole year. And look, the raindrops have started falling too. Even the weather is turning… thanda thanda, cool cool.”
(To be continued)
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