Cooks in Asia and India have use banana leaves in many of the same ways Western chefs use aluminum foil or parchment paper. According to an article on the Sampradaya Sun news site, banana leaves do not grow on trees but are actually the leaves of a large herbal shrub.
In India, banana leaves are so large they are used as umbrellas during monsoon season. They are used as natural food wrappers when steaming, grilling and baking different types of food. The leaf also make an attractive serving platter because of its size and sturdiness. The shrub produces only one leaf per month in winter and three to four per month in summer.
In addition to their value as food wrappers for cooking, banana leaves contain large amounts of polyphenols such as epigallocatechin gallate, or EGCG, also found in green tea. Polyphenols are natural antioxidants found in many plant based foods. According to an article by Augustin Scalbert and colleagues published in the January 2005 issue of the “American Journal of Clinical Nutrition,” extensive research is ongoing to help determine the extent of how polyphenols affect human cells, the oxidative process and its impact on disease prevention.
Source: Live Strong