Milky Coffee

[jadyn]

I make milky coffee by filling a glass mug with milk, pouring the milk into a pyrex jug, heating the milk to almost boiling and then pouring the milk back into the cup.

While the milk is heating, I put coffee granules and sugar into the cup ready to receive the milk.

How come when I pour the milk into the cup, I've always got some milk left over in the jug that won't go in? Surely it can't be because of the coffee and sugar in the cup as both these dissolve in the milk or could they affect the volume available in the cup for the milk?

Thanks.

[jadyn]

Sorry, I should have said that I heat the jug of milk in the microwave oven.

[dundurn]

When you heat the milk it becomes less dense and expands in volume.

[weeal]

why dont u just put milk in the cup and put the cup in the microwave, then add sugar n coffee?

[jadyn]

Why does the milk behave in this way dundurn? Is there a name for this phenomenon? Does the say apply with water?

weeal, I could do as you suggest. It's just that old habits die hard as they say!

[Conk]

Anything that is heated undergoes thermal expansion, which is why hotair balloons rise into the air, and why the ceiling of your house is always warmer than the floor, unless you use a ceiling fan to disturb the natural heat flow. Although the coffe will dissolve into the milk, it doesn't just lose it's volume, so yes, it will displace some of the milk, both forces are in action here.

[rojash]

Only old ladies from oop North drink coffee made with milk...

[jadyn]

Ooh you cheeky thing rojash. I've got something like fifty years ahead of me before I could be called an old lady and I live down south.

Just remember that much of the muck they sell in Starbucks is only deluxe versions of milky coffee at the end of the day.

[rojash]

Exactly, jadyn. Every time someone on TV says "I'll have a lahhhtay" thinking they are being cool, I just think "Oooh you old lady from oop North, you".

[pips1]

Blimey Tonyted - bit strong