Zheng He's fleet grew mung bean sprouts to prevent scurvy

Zheng He's seven Ming-dynasty naval expeditions, beginning in 1405, deployed fleets of hundreds of ships and crews numbering in the tens of thousands on voyages that could last many months and range across the Indian Ocean to East Africa and the Arabian Peninsula.

There was no stored food that could supply fresh nutrients for months at sea; salted meat, dried grain, and preserved goods all kept, but none of them addressed whatever was causing the wasting sickness sailors called 'sea disease.' Rather than relying on what could be carried and preserved before departure, the fleet's provisioning included growing a fresh food source continuously, on board, throughout the voyage.

Soaked mung beans already carried as dry stores, letting them sprout in trays to convert starch into vitamin C, producing fresh nutrients continuously.

Sprouting converts bean starch into vitamin C, which dry beans lack.

Sprouts grow in days using only water, warmth, and trays, no soil or sunlight.

Continuous sprouting provided fresh nutrients throughout multi-month voyages.

No scurvy outbreaks recorded, unlike European voyages where crews died in large numbers.

When a resource can't be stored, manufacture it locally from raw materials on hand.

Across Zheng He's seven expeditions there are no surviving records of scurvy outbreaks, a striking contrast with European long-distance voyages of the following centuries, where the disease routinely killed a large share of a ship's crew. The mechanism worked because sprouting converts a bean's stored starch into vitamin C as it germinates — dry mung beans carry almost none, but the sprouted version supplies enough to meaningfully offset a diet otherwise stripped of fresh produce.