TadkaClear

How is a tadka done?
A spoon of ghee, a pinch of cumin, ten seconds, and a plain dal becomes a different dish. See why spice flavours hide from water and rush into fat, why a mustard seed pops at about 6 bar, and how few seconds lie between done and burnt. Then do the tadka yourself.

▶ Play with it  ·  Read the 60-second explainer  ·  Watch the 40-second video

In 60 seconds

1. Four things and thirty seconds. A tadka (chhaunk, baghaar, phodni, vaghar, phoron, thalippu, oggarane, popu) is whole spices fried for a few seconds in hot fat, with that fat poured into or over the dish. It needs a small deep pan, about a tablespoon of ghee or oil, a pinch of spices and the dal they are for.
2. Flavour lives in the fat. Cuminaldehyde in jeera, capsaicin in chilli, curcumin in haldi and the terpenes of curry leaves are oily molecules. Chemists measure this with log P: capsaicin scores 3.6, which means about 4,000 to 1 in favour of an oily layer over water. So a tadka is flavour extraction into hot fat, and the fat then carries the flavour through the dish.
3. Every sound is steam. A mustard seed holds about 6% water sealed in its coat. In hot oil the steam pressure inside climbs to about 6 bar at 160 °C and 10 bar at 180 °C, and the seed bursts. Curry leaves splutter as their water boils off. The sizzle on the dal is water flashing to steam: one gram makes about 1.7 litres.
4. The window between done and burnt. Each spice runs two clocks: done and burnt. Heat speeds up burning more than it speeds up cooking, so the gap closes as the oil gets hotter. In this box's model cumin has from 12 to 35 seconds at 180 °C and no window at all above about 208 °C. That is why mustard goes in first and powders go in last, off the heat.
5. The fat sets the limit. A tadka runs at about 160 to 190 °C. Ghee and mustard oil smoke at about 250 °C; unrefined coconut and sesame oil at about 177 °C. Used oil smokes sooner, and FSSAI says oil with more than 25% total polar compounds must not be used. Never put water on burning oil: turn off the gas and cover the pan.
6. One idea, many kitchens. Jeera and hing in ghee in the north, panch phoron in mustard oil in Bengal, mustard seeds, urad dal and curry leaves in the south. It can come at the start, so the food cooks in the flavoured fat, or at the end, so the freshest aromas reach the table. China's oil-splashed noodles and Italy's soffritto are cousins.

Words worth knowing

Term	Meaning
Tadka	Whole spices fried for a few seconds in hot fat, and that fat poured into or over a dish. Also called chhaunk, baghaar, phodni, vaghar, phoron, thalippu, oggarane and popu.
Fat-soluble	Dissolving in fat and oil far more readily than in water. Most aroma molecules of spices are like this.
log P	A measure of how a molecule shares itself between an oily liquid and water. Each step of 1 means ten times more in the oil.
Saturation pressure	The pressure of steam in balance with water at a given temperature: 1 bar at 100 °C and about 10 bar at 180 °C. It is what bursts a mustard seed.
Myrosinase	The enzyme that makes mustard sharp. It needs water and is destroyed by heat, so mustard popped in oil tastes nutty.
The window	The time between a spice being done and being burnt. It narrows as the oil gets hotter, because burning has the higher activation energy.
Activation energy	The energy barrier a reaction must cross. The higher it is, the more heating speeds the reaction up.
Smoke point	The temperature at which a fat starts to break down into visible smoke: about 250 °C for ghee and mustard oil, about 177 °C for unrefined coconut oil (typical values).
Total polar compounds	The breakdown products that build up in used cooking oil. FSSAI's limit is 25%.

A short history

Four thousand years from turmeric in a Harappan pot to hing planted in the Himalaya.

• 2400 BCE · Ginger and turmeric in a Harappan cooking pot (Cooks of Farmana, Farmana, Haryana)
• 77 · Rome pays for Indian pepper (Pliny the Elder, Rome)
• 1129 · A king writes down his kitchen (Someshvara III, Kalyani, Karnataka)
• 1500 · "When the ghee is hot, flavour it with asafoetida" (Ghiyath Shah and Nasir Shah, Mandu, Madhya Pradesh)
• 1530 · The chilli lands in India (Portuguese traders, Goa)
• 1889 · A formula for how heat speeds reactions (Svante Arrhenius, Leipzig)
• 1912 · The chemistry of browning (Louis-Camille Maillard, Paris)
• 1912 · A scale for chilli heat (Wilbur Scoville, Detroit, Michigan)

The full story, with 30 moments, charts, people and 44 sources: glassbox.how/e/tadkaclear/history. The data lives in history.json.

Video and slides

Made with the Glassbox studio from this box's storyboard (window.glassbox.director). Free to reuse under CC BY 4.0.

File	What	Size
glassbox/reel.mp4	Reel / Short, with captions and soundtrack	1080×1920
glassbox/video.mp4	YouTube video, with captions and soundtrack	1920×1080
glassbox/slide-1…10.jpg	Instagram carousel	1080×1350
glassbox/thumb.jpg	YouTube thumbnail	1280×720
glassbox/cover.jpg	Share card and repo social preview	1200×630
glassbox/history-reel.mp4	“History in 10 moments” Reel / Short	1080×1920
glassbox/history-slide-*.jpg	History carousel	1080×1350
glassbox/post.json	Post copy and schedule used by the publish kit

Privacy

This box has no accounts and no ads, and it ships its own fonts and libraries. When you run it yourself it sends nothing anywhere. On glassbox.how, the site's /bar.js also loads Glassbox's analytics: Google Analytics to count visits (it asks first in the EU, UK and Switzerland, and stays off when your browser sends Global Privacy Control or Do Not Track) and ClickTrust to detect bots.

It remembers a few things in your own browser only, and never sends them anywhere:

Browser storage key	What it holds
tadkaclear.v1	Which chapters you have opened, your best quiz scores, and sound on or off.

Exactly what each one sees is at glassbox.how/privacy.

Licences

• Code: MIT. Use it, change it, ship it.
• Explanations, text, images and videos (glassbox.json, glassbox/): CC BY 4.0. Credit “Glassbox, glassbox.how/e/tadkaclear”.
• Third-party parts keep their own licences: three.js (MIT), Geist, Instrument Serif (SIL OFL 1.1).
• The Glassbox name and logo aren't covered by either licence. See the terms.

Found a mistake? Open an issue. Corrections happen in public.

Run it

It's plain HTML, CSS and JavaScript. No build step and no dependencies. Run locally, it contacts no other website.

python3 -m http.server 8000

Three.js and the fonts ship in vendor/ and fonts/, so it also works offline.

Then open http://localhost:8000.

How it's built

File	What
index.html, css/app.css	The page and its styles
js/app.js, js/stage.js, js/ui.js, js/kit.js	The shared Glassbox 3D engine: chapters, 3D stage, controls, quiz, video director
js/chapters/*.js	One file per chapter: the 3D model, controls, text, key terms, quiz and video scenes
js/tadka.js	Shared tadka physics (the small pan's heat balance, steam pressure in a mustard seed, the two Arrhenius clocks for done and burnt), the spice and oil tables, the cut-open tadka pan, chart boards and helpers
glassbox.json	Title, question, explainer beats, key terms, browser storage and credits shown on glassbox.how
reel in each chapter	The storyboard the Glassbox studio records into short videos
glassbox/	The published video, slides, thumbnail and post copy
fonts/, vendor/three/	Self-hosted Geist and Instrument Serif (SIL OFL 1.1) and three.js (MIT)