🥔 Discovery of Inca freeze-dried potatoes

An astonishing discovery has been made by archaeologists on the arid coast of southern Peru: two freeze-dried potatoes about 500 years old.

These specimens, from the Inca site of Tambo Viejo in the Acarí Valley, were found in a ceramic pot. Their presence in this coastal region is unexpected, as this preparation requires the freezing nights of the high Andean mountains. This find provides tangible evidence of the scope of the supply networks of the Inca Empire.


These dehydrated tubers, called chuño, were a staple food in the Inca Empire. The manufacturing process is ingenious: potatoes are exposed to overnight frost on the high plateaus, then left to thaw in the sun, repeating this cycle several times. Then they are trampled underfoot to extract moisture. The result is a lightweight product that can be stored for years without refrigeration. There are two varieties: black chuño, made from ordinary potatoes, and white chuño, made from bitter varieties that require prolonged soaking after freezing.

The two discovered chuños are whitish-brown in color and still retain fragments of their skin. These samples were unearthed in 2024 during excavations led by Dr. Lidio Valdez of the University of Calgary. They were placed in a ceramic pot buried in the ground, used as a storage container. Nearby were a piece of Inca pottery and a damaged spindle. These everyday objects allowed the whole to be dated to the Inca period, between the 15th and 16th centuries.

In Inca times, chuño was an essential food, comparable to bread for populations. Spanish chroniclers reported that llama caravans transported these supplies to storehouses scattered across the territory. They served to feed the empire's workers, including those at Tambo Viejo. Lightweight, durable, and produced in large quantities, chuño was one of the most important foods for supporting Inca administration and armies.


Despite its past abundance, chuño is rarely preserved at archaeological sites. The only other comparable discovery dates back over a century, at Pachacamac, also in Peru. The arid conditions on the coast and storage in a jar likely allowed these specimens to survive to the present day. This rarity has led to an underestimation of the importance of chuño compared to other foods like dried meat.

Researchers would like to know the exact origin of these potatoes. Chemical analysis could identify the mountain region where they were grown. Dr. Valdez hopes to continue this research, as each excavation campaign at Tambo Viejo yields surprising results. He considers this site unique for understanding the Inca economy.

This discovery highlights the ingenuity of the ancient Andeans and their ability to turn perishable products into durable foods. Chuño, though modest, reveals the extent of the exchange and storage networks of the Inca Empire.

The logistical organization of the Inca Empire

The Inca Empire stretched over more than 2,500 miles (4,000 km) along the Andes mountain range. To manage such a vast territory, the Incas established a system of roads and storage depots called qollqas. These storehouses were scattered along the imperial roads and allowed supplies to be provided to troops, officials, and workers.

Foodstuffs such as chuño, corn, or dried meat were transported by llama caravans. Each llama could carry about 66 pounds (30 kg) of goods. Products were redistributed according to needs, ensuring a degree of regional self-sufficiency.

The discovery of chuño on the coast proves that these networks functioned effectively. Highland foods reached coastal areas, where they were used to feed local populations or workers assigned to state projects. This efficient organization contributed to the power and sustainability of the Inca Empire.