Hi SUDHKAMP
According to Answers.com, 'The origin of this metaphorical expression has been lost, but the positive version--"he's my cup of tea"--has been used since the late 1800 and the negative--
not one's cup of tea--since the 1920s.'
However, Bigalowteablog.com has the following to say:
The phrase “not your cup of tea” means that something is “not to your liking.” According to the Translation Dictionary the expression got its start in the late 1800s when Brits, when referring to the popular drink, began saying that something they liked was their “cup of tea.” But time changes things. Later, probably sometime in the 1920s, the expression took a twist to indicate the opposite.
By the way, there's a North American variation,
not my pot of fish.
