The bark from several mangrove species can be used to extract natural tannin. Tannin is an important ingredient in natural dyeing and for leather processing, although both has been significantly replaced by man-made chemicals. Recently however, there is an increasing trend to go back to the natural process.
Green Forest has developed a method to effectively extract and dry the tannin into high concentrate powder form. The powder can be mixed with warm water to re-form the tannin liquid. Tannin powder from Ceriops tagal, extracted from waste bark at PT. BUMWI, has been sold to a foundation in Bali since 2017. We will develop the market further and hope we can sell the tannin from Rhizophora apiculata, which is a dominant species in Indonesia.
Green Forest is also working closely with Nanyang Technological University to further develop the tannin for other uses. Furthermore, PT BUMWI is working with Gadjah Mada University to further improve the extraction and drying process, as well as characterizing the tannin from each species.