Milk, milk bottles and bottle tops in mid-20th century Britain
By the 1940s and 50s when I was growing up, people no longer had to use their own jugs when buying milk. Several types of milk were available, each in its own type of milk bottle which was always glass. I ever saw any cartons and of course plastic was years away.
Milk was always delivered to the doorstep of houses, although extras in emergencies could be bought from the local dairly. When a milk bottle was empty it was dutifully washed out and left on the doorstep for the milkman to collect on the next delivery I understand that they were then sterilised back at the dairy, before re-use.
I understand that sterilised milk had undergone some sort of heat process to kill any bacteria in it. The sterilisation certainly affected the taste which you can get an idea of by boiling some of todays milk and letting it get cold before tasting it. Sterilised milk did have the advantage of lasting longer than the fresh milk which was important as there were no fridges in ordinary homes.
My mother insisted on having steralised milk. She wouldn't be budged. So our milk deliveries came from the Co-op partly because it sold sterilised milk but also because the Co-op paid dividend on purchases. Methods of treatment which retained the true taste of the milk were years away.
Steralised milk bottles
Steralised milk bottles were taller than other milk bottles, had a narrow neck and a metal crimped top which needed a a metal opener to prise it off. As far as I know, these tops just got thrown away - unless you know any different. If so, please let me know.
Fresh milk and 'top of the milk'
Occasionally I was given fresh milk from the United Dairies at friends' houses. I loved it, especially the cream which rose to the top, and could be seen as a deeper colour through the transparent glass bottles. This was known to everyone as the 'top of milk', and sadly it is a thing of the past following homongenisation.
The variety of milk bottles and bottle tops
I only ever saw pint and half pint bottles outside school; school milk came in 1/3 pint bottles. All bottles were clear glass.
There were two main qualities of milk depending on the cream content. The standard quality was basic but nevertheless tasted as if it had more cream than today's skimmed milk. It could be recognised by the silver foil top to its milk bottle - although some dairies used other colours. Gold tops, though, were reserved for the creamier and more expensive milk, This was called 'gold top' milk and it was delicious. Incidentally I don't remember seeing any cream sold as cream in the 1940s. If it was available, it was for the comparatively wealthy. It started coming into the shops sometime in the late 1950s and early 1960s. As a married woman in the 1960s, recipes were still quoting 'top of the milk' and I was still using my cream-making machine which made cream from milk and butter. Yoghurt came in at about the same time as cream.
Bottle tops and campaigns to collect them
Foil milk bottle tops were good for keeping children amused because they could be pressed onto objects or coins to make them look silver.
Schools and clubs frequently had campaigns to collect the foil tops for salvage in aid of charity. Guide dogs for the Blind was common in our area. There was no central drive to do this, and most housewives thought nothing of putting the foil tops into the dustbin.
Although dairies in most areas of the UK did close their milk bottles with foil tops, some areas used waxed cardboard discs instead.
How to open the foil tops of milk bottles
The easiest way to remove a milk bottle's foil top was to press it with a finger or thumb. Being foil, it was thin enough to dent, but as it didn't stretch, it came away round the edges.
Foil milk bottle tops could also be removed with a careful unscrewing motion. This way, the milk-bottle top retained its shape, so it could be used as a miniature frisbee by flicking it between the index and middle fingers. Because of their small size and light weight, milk-bottle tops could be flicked in the classroom while the teachers's back was turned. Incidentally, I don't recall seeing regular-sized frisbees in the UK until long after that time.
Laurie Prior describes a simple tool called a denter for doing the same thing in the late 1950s (once the use of plastic had become more widespread). He reports that the denter did the job rather more cleanly, but I never saw one. Its use is described on the page about free school milk.