Effect of production site and storage on antioxidant levels in specialty potato (Solanum tuberosum L.) tubers

BACKGROUND: The potato can make a significant contribution of antioxidants to the human diet. In this study, antioxidant levels in tubers of 14 specialty potato clones grown at four production sites (two conventional, two organic), both fresh and stored, were examined across 2 years. RESULTS: Antioxidant activity of fresh tubers at all locations was higher in 2006 than in 2005. Cooler late‐season temperatures in 2006 may have been responsible for the increased levels of antioxidants. Stored tubers had higher levels of antioxidant activity than fresh tubers, with a larger storage effect in 2005, when antioxidant levels in fresh tubers were lower. There was no consistent effect of production system (organic versus conventional) on antioxidant activity in tubers. CONCLUSION: For the specialty potato clones we evaluated, antioxidant levels were generally highest in potatoes grown in high‐yielding production environments, and they increased during storage. Therefore, potatoes with high nutritional value, in terms of antioxidant activity, can be produced using conventional production and storage systems.