According to PBS Eons, the taste of sour may have been something that evolved over millions of years.
Although it alerted living creatures to danger at first, it is now an enjoyable flavor for many.
As you may know, humans and some animals are unable to make their own vitamin C.
Many of the foods that are rich in vitamin C have a sour taste, which may have been what led people and animals to seek out that sour taste.
Something else that may be associated with enjoying sour food is fermentation. As fermentation increases, the nutritional value may also increase in the food.
Many of the foods that ferment are also sour, which is another reason why we may seek out that taste and even enjoy it.
Pretty interesting, right?
Learn more in this video from PBS Eons: