What is the supply chain structure of Madagascar vanilla?

The linear representation of the export supply chain for Vanilla can be represented by: 

Farmers > Commissionaires > Collectors > Processors > Exporters 

Farmers usually partnering with collectors who are local middlemen that liaise with and purchase the products from the farmers, working as an intermediary between the farmer and the exporter. Collectors will then process the vanilla and then proceed to the exporter for quality control. 

When the vanilla passes through the quality control, it is then proceeded to brokers or trading partners and will be further processed by grinders, packers, flavor, and fragrance houses. The end of the supply chain is the final distribution to retailers and manufacturers. However, there are also a few large companies that work directly with the farmers, thus the sector is not vertically integrated.

Source: Tridge Analysis on the Vanilla Industry in Madagascar