Indian curries change character every few hundred kilometres. We distinguish them not by their main ingredients but by the souring agents.
If you enjoy eating sour food, consider cooking with some of these natural souring agents to enhance the tangy flavours.
Malabar tamarind or kudam puli is a souring agent used in a number of curries in Kerala and Karnataka. A drink prepared with it may help lose weight.
Coconut vinegar is used in a number of dishes of Goan cuisine as a souring agent and a flavour -enhancer. It's also used in preparing the desi Goan alcoholic drink - coconut feni.