Milk in first or last in a cup of tea? Scientist settles great debate - but it depends where you live

You can’t beat a good cup of tea - but there's an endless debate on how to drink it. There are many brands and lots of different flavours to choose from. You can choose teabags or loose leaf tea. You can serve it in a teapot or a favourite mug.

Whatever your preference, there’s one divisive question that rumbles on: do you put the milk in first or last? Now, following International Tea Day, one scientist claims to have finally found the definitive answer. But, do you agree?

Professor Alan Mackie of Leeds University has said that you’ll get the best cuppa if you put the milk in the cup after the tea bag but before the hot water - although perhaps this is only the case if you live in certain areas of the UK.

That’s because the research Mackie is basing his suggestion on found that putting milk in first helps counteract hard water. Hard water occurs when there is a high number of dissolved minerals, predominantly magnesium and calcium, in the water. Homes which have hard water are commonly found in South East England and London. Professor Mackie believes people living in these hard water areas may enjoy their brews more if they use the milk first method. 

He said that proteins in the milk lower the mineral content of the water, and this gives the tea extra flavour, particularly when the water is hard. As reported by the Daily Mail, he explained: “Flavour by and large is produced by the different compounds in tea including tannins in particular. The more minerals present in water the more difficult it is for these compounds to develop the flavour - resulting in the dull cuppas you get in hard water areas.

“Making tea the traditional way - steeping a bag in hot water before removing it and adding milk - results in the tannins turning into solids before they can develop the flavour properly. But, if the milk is added at the start of the steeping process then its proteins can bind to the tannins and other minerals in the water - preventing them from turning solid - which in turn gives you a far superior flavour.”

Research carried out in conjunction with INTU, a manufacturer of boiling water taps, found that minerals in hard water do prevent flavour compounds forming in a cup of tea. Kieran Taylor-Bradshaw, Managing Director of hot tap manufacturer INTU Boiling Water Taps, also told the Mail: “A decent cuppa brings joy and brightens the day, but for too many it remains a distant dream, with hard water to blame.”

So, this research could also point to the fact that people who live in soft water areas could put the milk in last, if they wish, and the taste of their cuppa will be just the same.

Areas which have soft water tend to be more northern, especially Scotland, Ireland and Wales. Water is naturally soft when it falls from the sky and gains its hardness after coming into contact with the ground. If water falls on non-porous rock such as granite, the water cannot penetrate the ground and therefore cannot pick up any particles or minerals and so stays soft, according to Aquacare.

If you would like to know what the water is like in your area, you can enter your postcode on the Aquacare website using the hard water map.