Kerala is part of the Malabar Coast of southwestern India which is famous for its spices, particularly pepper. Spice trade continues in Cochin at the International Pepper Exchange, spice drying facilities (ginger in this case), warehouses, and spice stores for locals and tourists alike. The Communist Party (CP) plays a major role in the politics of Kerala as it does in Calcutta. The Party's presence is widely displayed with symbols and flags. CP allocates work in the spice market as workers wait for employment. The main spices of Kerala are Cardamom, Cinnamon, Cassia, Clove, Ginger, Nutmeg, Mace, Pepper, Turmeric, and Vanilla.

The Muslims who traded in pepper were Sufis and the local converts to Islam were largely low-caste Hindus breaking free of the caste system. These south Indian Muslim converts, who represent about 25 percent of Kerala's population, have maintained many of their cultural traditions: matrilineality, songs, folklore, and Malayalam language. They also build distinctive mosques (palli), unlike mosques elsewhere -- see the photo below. Read more about Muslims and pepper in the Saudi Aramco World. The converted St. Thomas Christians likewise maintained many of their Hindu cultural practices.

Source: http://www.shubhyatra.com/kerala/kozhikode.html