The Chemistry of Diwali Disasters: How Science Saved Our Sweets
Blog post description.
Saumya Wagh
12/26/20242 min read


I have to tell you about the most epic science win that happened in my kitchen last Diwali! So, Diwali was literally two days away and my dad decided to surprise my mom by making her favorite sweet - kaju katli (those amazing diamond-shaped cashew treats). Big mistake.
I'm upstairs doing school homework when I hear this frustrated groan from the kitchen. I rush down to find my poor dad staring at what was supposed to be smooth, gorgeous kaju katli but instead looked like... well, imagine if someone tried to make Play-Doh out of gravel. It was this grainy, sticky disaster that wouldn't hold together at all.
Enter: Your Friendly Neighborhood Chemistry Nerd!
I looked and thought it through, and I immediately saw this as the perfect real-world chemistry problem! After interrogating my dad about his process (sorry Baba, but science waits for no one), I figured out what went wrong.
Turns out kaju katli is all about controlled sugar crystallization! When you make the sugar syrup, you're creating a supersaturated solution - basically forcing more sugar to dissolve than normally would. As it cools, those sugar molecules want to form crystals again. In perfect kaju katli, these should be tiny, microscopic crystals that create that amazing melt-in-your-mouth texture.
But Dad's katli had these huge, grainy crystals because he'd made two crucial mistakes: he didn't heat the sugar syrup to the right temperature (it needs to reach exactly 234°F for that "one-string consistency"), and he let it cool completely before mixing, giving those sugar molecules way too much time to form big ugly crystals!
The Scientific Rescue Mission
Armed with my chemistry knowledge, we started over! This time we used a candy thermometer, added some sugar syrup to interrupt crystal formation, and kneaded while the mixture was still warm. The result? Absolutely perfect kaju katli that would've made my Indian grandmother proud!
Who knew that understanding phase transitions and crystallization could literally save Diwali?? Now my dad calls me his "sweet scientist" and honestly, I'm living for it!
Teens celebrating Diwali, remember that our traditional recipes aren't just delicious, they're edible science experiments that connect us to both our heritage and the universal laws of chemistry!!
