Butter, just like margarine, should not be stored in a package. This is, at least, ugly, and at most – unhygienic.
Usually, it is customary to transfer the butter into a special butter container and send it to the refrigerator shelf in this form.
However, even if you do everything correctly, the product may acquire an unusual smell.
To find out the reason why fresh-looking oil has undergone such unpleasant changes, it is enough to carefully examine the dishes in which the product was stored.
The fact is that most butter pots that you can buy in the cookware section of the supermarket have a clear top lid.
It certainly looks very aesthetic, but impractical.
This is due to the fact that butter and margarine should be stored in opaque containers. The unpleasant "aroma" acquired by these products arises precisely because of interaction with light.
Therefore, if you often began to notice that the butter has changed its taste, just try to replace the butter.