The diverse climate in the region, ranging from deep tropical to alpine, has also helped considerably broaden the set of ingredients readily available to the many schools of cookery in India.
In many cases, food has become a marker of religious and social identity, with varying taboos and preferences (for instance, a segment of the Jain population consume no roots or subterranean vegetable; see Jain vegetarianism) which has also driven these groups to innovate extensively with the food sources that are deemed acceptable.
[1] After 9000 BCE, a first period of indirect contacts between Fertile Crescent and Indus Valley (IV) seems to have occurred as a consequence of the Neolithic Revolution and the diffusion of agriculture.
[note 1] Around 7000 BCE, agriculture spread from the Fertile Crescent to the Indus Valley, and wheat and barley began to be grown.
Some plants like sarabhi of family Guttiferae, kanika or harsinghar, phikun or Mimusops elengi and bunnak or the rose chestnut etc.
Indian influences can also be noted in rice-based delicacies such as bibingka (analogous to the Indonesian bingka), puto, and puto bumbong, where the latter two are plausibly derived from the south Indian puttu, which also has variants throughout Maritime Southeast Asia (e.g. kue putu, putu mangkok).
This is said to explain the name and its supposed thick, yellow-to-orange annatto and peanut-based sauce, which alludes to a type of curry.
[citation needed] Later, arrivals from Arabia, Central Asia,[44] and centuries of trade relations and cultural exchange resulted in a significant influence on each region's cuisines, such as the adoption of the tandoor in Middle East which had originated in northwestern India.
[47][48] A 2019 research paper by US economist Joel Waldfogel, based on travel data from TripAdvisor, affirmed India's soft power which ranked Indian cuisine fourth most popular.
Indian cuisine is especially most popular in United Kingdom, South Korea, Thailand, Japan, Germany, France and US.
[49] In another 2019 survey of 25,000 people cross 34 countries, the largest fans of India cuisine who have tried it are the Indians (93%), British (84%), Singaporeans (77%), Norwegians (75%), Australians (74%), French (71%), Finnish (71%), Malaysians (70%), Indonesians (49%), Vietnamese (44%), Thai (27%), and mainland Chinese (26%).
[50] The Washington Post reported the results of a 2019 study by the researchers at the Indian Institute of Technology Jodhpur, which analysed over 2,000 popular online recipes from Tarla Dalal's portal "TarlaDalal.com" containing 200 ingredients out of the 381 known globally.
Data scientists studied the numbers and amount of molecular flavour compounds shared by each ingredient combined in a dish.
[69] Indian cuisine is very popular in Southeast Asia, due to the strong Hindu and Buddhist cultural influence in the region.