Because of its rich trading heritage, over time various indigenous Kerala dishes have been blended with foreign dishes to adapt them to local tastes. Coconuts grow in abundance in Kerala, so grated coconut and coconut milk are commonly used for thickening and flavouring. Kerala's long coastline and numerous rivers have led to a strong fishing industry in the region, making seafood a common part of meals. Rice is grown in abundance along with tapioca. It is the main starch ingredient used in Kerala's food.