Re: Does it matter if you put milk in tea 1st or 2nd?

Jonathan:

As far as I know there is no reaction between the milk and the tea (milk molecules and tea molecules do not interact.) So from a chemical point of view it would not matter which went in first.

Not being a tea drinker myself I am not quite sure what you mean by scalding the milk, but milk is a colloid - a suspension of 'blobs' of milk in water - and it is possible that pouring this into a hot cup of tea would affect the colloid particles. Perhaps they stick together to form larger particles (although we know that the milk and tea mix alright - we don't get seperate layers) and thie size of the colloid particles affects the taste of the milk?

I'm afriad I haven't been able to find much research about the chemistry of cups of tea, or that of milk itself. However, I do know that one of the first physics calculations that the cosmologist Stephen Hawing did for himself was to show that a cup of tea will cool down more quickly if you leave putting the milk in just before you drink it. This is because of Newton's law of cooling which says that the rate of energy loss from the tea wil be proportional to the temperature difference between the tea and it's surroundings. Putting the milk in straight away cools down the overall temperature and the heat energy is not lost so quickly. (sorry, but you'l have to ask a physist if you want to see the calculations done!)

I'm sorry I haven't been more help, but I am left to conclude that it probably doesn't make any difference which goes in first except to the temperature. But then, as I said, I don't drink tea, so what would I know?!