Professor Hannah Fry, a mathematician and star of the BBC's Celebrity Traitors, has said that Brits might appear "completely insane" if they use an "erratic" technique when making their next cup of tea. She claims this method produces the best-tasting cups of tea.
A YouGov poll revealed that, on average, roughly a quarter of Brits (24%) have their usual cup of tea with added sugar. The results show that, of those who do put sugar in their tea, 14% use one teaspoon and 10% use two.
The science-backed stirring method
Fry has previously said that people who prepare their tea with an "erratic" stirring method could experience a better taste by following a science-backed technique that dissolves more sugar. She says it is, in fact, a "terrible idea" to stir your tea in a circle to help the added sugar dissolve more quickly.
Speaking on The Rest Is Science video podcast, which she presents with American educator and Vsauce creator Michael Stevens, Fry said: "The sugar will dissolve much better in a turbulent fluid."
Fry claims: "I stir tea like this. Just do an erratic shape with your teaspoon, you look completely insane." Stevens added: "This is what I do when I need to get salt to dissolve in pasta water."
Why erratic stirring improves taste
In general, tea will taste considerably better if you adopt Fry's approach, reports the Mirror. It stops sugar from settling and accumulating at the bottom of your mug. This prevents the first few sips from tasting noticeably more bitter than the very last, which would otherwise become an unpleasantly sweet residue.
Once fully dissolved, the sucrose molecules in the sugar are evenly distributed throughout the mug. Every single sip will taste precisely as you intended, from beginning to end.
What is the science behind this?
When you stir a teaspoon in a consistent circular motion, you produce a neat, predictable whirlpool. Rather than dissolving, the solid sugar crystals get caught in the current and settle directly in the centre at the base of the mug, much like how tea leaves settle.
To dissolve sugar or blend milk effectively, you need a turbulent flow. This almost chaotic movement is full of tiny, unpredictable currents that exert a considerably greater force than a gentle stir. As the liquid collides with itself and with the solid sugar crystals from varying angles, it breaks the sugar crystals apart and incorporates them into the hot water far more rapidly than a smooth whirlpool ever could.
