A food hub is intermediary infrastructure: a regional operation that buys from many small farms, aggregates and sometimes processes the product, and sells to wholesale buyers (restaurants, grocers, institutions). The USDA's formal definition emphasizes the hub's role in strengthening local/regional food systems.
For small farms, food hubs are often the bridge to wholesale channels that would otherwise be out of reach — the hub handles the cold-chain logistics, food-safety audits, invoicing, and buyer relationships. The farm gives up some margin but gains reliable volume and simplified operations.