  Culinary practices are influenced by climate, culture, history and geography.
Molecular composition of recipes in a cuisine reveals patterns in food
preferences. Indian cuisine encompasses a number of diverse sub-cuisines
separated by geographies, climates and cultures. Its culinary system has a long
history of health-centric dietary practices focused on disease prevention and
promotion of health. We study food pairing in recipes of Indian cuisine to show
that, in contrast to positive food pairing reported in some Western cuisines,
Indian cuisine has a strong signature of negative food pairing; more the extent
of flavor sharing between any two ingredients, lesser their co-occurrence. This
feature is independent of recipe size and is not explained by ingredient
category-based recipe constitution alone. Ingredient frequency emerged as the
dominant factor specifying the characteristic flavor sharing pattern of the
cuisine. Spices, individually and as a category, form the basis of ingredient
composition in Indian cuisine. We also present a culinary evolution model which
reproduces ingredient use distribution as well as negative food pairing of the
cuisine. Our study provides a basis for designing novel signature recipes,
healthy recipe alterations and recipe recommender systems.
