As a lunchtime diversion, I’ve been carrying out an experiment – but I’ve reached the limit of my equipment and knowledge. Any ideas welcomed!
I drink very weak black Earl Grey tea. It’s too hot to drink straight from the water heater or kettle, so after briefly dangling the tea bag in the mug, I add a dash of cold water.
For years I’ve noticed that it seems to get darker when I add cold water from the office water cooler (that’s the scientist in me).
For years I’ve done nothing with this observation (that’s because I hated practical labs – I did two computer simulations for my final year projects…).
However, today I cracked. This is one mug of tea, divided equally between two glasses, with, on the left hand side, a dash of cold tap water added, and, on the right hand side, an equivalent dash of cold water from the water cooler. Both have been left to reach room temperature.
I also had a bottle of One spring water in my office, so next up was a similar brew, though this time using a standard Careers Service PG Tips teabag – one brew divided between three glasses.
Not as easy to see, as photographed from the side, but guess which one’s which?
Far left – added tap water; middle – added bottled One spring water; far right – added water cooler water.
So, in the absence of any further equipment (or time over lunch) – why does the water cooler water make tea go darker? These are the practical issues our postgraduate scientists should be working on!