There have been many times when I am just about to have some milk, that I hesistate and remember that I had bought it quite a while ago. I then proceed to smell it and perhaps taste a bit. Usually, just to be safe, I just throw it away anyway, however I am rarely sure unless it comes out in lumps; which it has done before.
If there could be some kind of indicator that could show us if the milk has gone off then it wouldn’t require us to smell or taste potentially putrid milk. Adding an indicator onto the packaging of every milk bottle would probably raise the price of milk too much to justify adding it.
A cheaper solution, in the long term, would be to have an external indicator or sensor that can be put on every milk bottle that we buy. A possible place to put a sensor would be the cap. We could replace the cap of our milk bottle with another one that contains a sensor, which can then be reused with every new bottle we buy.
The sensor could change colour or provide us with a visual indicator to show if the milk has gone off. Alternatively, it could even connect to our phone and tell us at the exact moment if our milk is no longer good to drink. This can then allow us to buy milk before the moment we need to use it.
In terms of the sensor, I have heard sensors that are being developed to be used in supermarkets to test food. Most of the sensors I have read about are also very cheap, cost pennies, so could make this product very cheap and accessible. This sensor could also be used on other food, especially if it is cheap. Unfortunately it could mean that we might end up having to charge milk caps.
As always, if you think you have a solution or if you have a problem you would like me to try to solve then please feel free to comment it.