The origin of this tradition is unconfirmed, but some say it may have developed from Cape Malay cuisine during colonial times when vinegar and spices were used as preservatives.
From the WebMD Archives
Elizabeth Roberts had a friend she d known for 23 years. Roberts had grown up with this friend in a small town in Maine, and while longevity in a relationship often speaks to its strength, in her case, it was quite the opposite the older they got, the more the relationship turned toxic. She was always putting me down, says Roberts. Whether it was out in the open and obvious, or a subtle jab, it was exhausting.
For Roberts, the friendship seemed OK, and she took the insults in stride. I would mention to my mother or another friend something she said to me, and their responses were always, What? She said that? Who says that? says Roberts. And I would defend her. I would say, Oh, she doesn t mean it that way. But she did, and I just overlooked it.