From the AWAD on Monday (wok):

Every time you put a dollop of ketchup on your fries, you may be referring
to Cantonese, the possible source of the word.

More likely to be from the Indonesian/Malay kecap, meaning soy sauce.

Bingley

AHD4 suggests that it may be through Malay from Cantonese:

http://www.bartleby.com/61/32/K0043200.html