If you want to make a friend, sharing a cup of tea is a good place to start. If you want to make a sworn enemy, asking about the single, best way to make that cup of tea is an even better one.

For a drink that's really the height of simplicity (leaves + water + time), the humble cup of tea has inspired some fierce scientific debate. Over at The Guardian, Dean Burnett is covering the series of controversies that has surrounded a single, preoccupying question for researchers through the ages: Is there a scientifically perfect way to brew a cup of tea?

First up on the docket, when does the milk go in?

To test the recipe for the perfect cup of tea put forward in 1946 by George Orwell himself, Dr Stapley of Loughborough University established that putting the milk in after the boiling water is incorrect, as it causes the milk to heat unevenly (as opposed to pouring the water on top of it). This uneven heating of the milk causes the proteins in it to denature, meaning they lose their structure and "clump", affecting the taste and contributing to that skin you get on the top. So when someone says they can tell if you put the milk in first or second in the tea you've made for them just by tasting it, turns out they probably can.

So that settles it then. Milk before water in tea. End of discussion. Science has spoken!

Except it hasn't. As is always the case when you get science involved, it's not that simple. For instance, if the tea bag is in the milk before the water, this will cool the water too quickly, affecting the brewing. So if you make the tea in a pot, fine. If you don't, then that's a whole other issue

Okay, but what if you don't want any milk in your tea? What if all you want is to heat your kettle near to (but never past!) the point of boiling, steep for precisely three minutes in a pre-warmed mug, and then drink it undiluted, just as God and nature intended?

WHAT THEN, SCIENCE?

People often drink tea at specific times or in specific contexts (eg the office tea break) and we quickly grow to expect these, especially if we're the ones making it and develop our own pattern of doing so, based on our preferences. When someone deviates from this, it can explain the seemingly excessive reaction it provokes.

So, what's the scientifically "correct" way to make tea? Well, if by correct you mean "method that makes it taste best", then that's actually something that incorporates a fantastic number of variables in order to produce a highly subjective result. So, scientifically speaking, the correct way to make tea is "however you like it best".

Ah, okay. Well, carry on then.

Image: Haneburger