Oca (Oxalis tuberosa) is a starchy Andean tuber cultivated for thousands of years in the highlands of Peru and Bolivia, prized for both savory and sun-sweetened preparations. It remains a regional staple and the second most important root crop of the Andes after the potato.
History & Origins
Oca was domesticated in the central Andes of Peru at least 4,000 years ago, with archaeological remains recovered from pre-ceramic and formative-period sites in the Cusco and Ayacucho basins. By the time of the Inca Empire it ranked just behind the potato in cultivated area and was preserved by freezing and sun-drying, a process called khaya or cayo that converts its sour oxalate-rich forms into sweet, chewable tubers. Spanish chroniclers such as Pedro Cieza de León described the crop in the 1550s, noting its multiple colors and the Andean practice of exposing tubers to sunlight to enhance their sweetness.
Nutrition Facts
Per 100 g, edible portion (estimated)
- 61 kcalCalories
- 1.0 gProtein
- 0.3 gFat
- 13.6 gCarbs
- 1.5 gFiber
- 5.4 gSugars
- 355 mgPotassium
- 1.4 mgIron
- 26 mgVitamin C
Culinary Uses
- Boiled or roasted and served with cheese, ají, or honey
- Sun-sweetened (khaya) tubers eaten as a dessert or street snack
- Added to hearty Andean stews such as ajiaco and sancocho
- Sliced and pickled with lime and chili for accompaniment to grilled meats
- Dried and ground into flour for porridges and baked goods
Known Benefits
- Provides readily digestible complex carbohydrates for high-altitude energy needs
- Good source of dietary potassium, supporting electrolyte balance
- Supplies vitamin C, an important nutrient in highland diets historically poor in fruit
- Contributes dietary fiber that aids digestion
Hidden Benefits
- Colored red and purple varieties contain anthocyanins and betalains with antioxidant activity
- Naturally high in resistant starch, which functions as a prebiotic in the colon
- Sun-curing (khaya) increases free sugar content and concentrates polyphenolic compounds
- Some yellow and orange landraces provide meaningful levels of beta-carotene
Cautions & Considerations
- Contains oxalic acid and oxalate salts, especially in sour/bitter landraces
- People with a history of calcium-oxalate kidney stones should limit intake and avoid raw consumption
- Bitter varieties must be cooked or sun-exposed for several days to reduce oxalate levels to palatable levels
- May provoke mild reactions in individuals sensitive to oxalis-family plants
