Potato is the major tuber crop and the fourth most important food crop worldwide, the total world potato production was estimated at 388,191,000 t in 2017 and almost a third of all potatoes were harvested in China and India.
The nutritional quality of potato is important to human health whose staple food is potato. This tuber contains minerals, proteins and antioxidant compounds such as carotenoids, phenolics, flavonoids, vitamins C and E, among others.These phytochemicals in potato have attracted an increasing attention from the public because of their effects on promotion of physical well-being.
Scientists at Zhejiang University (Hangzhou, China) have investigated the contents of total phenolics (TPC), individual phenolic acid and antioxidant activities in the free and bound fractions of potato with different flesh colors. For the study, 14 potato cultivars (three white, seven yellow, two red, two purple) were planted and harvested in the Zhejiang University farm in Hangzhou.
"The TPC and antioxidant capacity in the bound fraction was significantly lower than that in the free fraction. Chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, caffeic acid, p-coumaric acid and ferulic acid were detected in the free fraction with chlorogenic acid being the most predominant, accounting for 35.21–81.78% of the total content. Caffeic acid, p-coumaric acid and ferulic acid were detected in the bound fraction in the colored potato with caffeic acid being the major one. In the free fraction, the content of each individual phenolic acid had positive correlation with antioxidant activity. In the bound fraction, caffeic acid and p-coumaric acid showed positive correlation with antioxidant activity", the scientists explain.
This study promotes further understanding of the correlations among TPC, phenolic acids and antioxidant activity. The results may further contribute to the knowledge of the genetic diversity in the phenolics and processing techniques to benefit the desired nutritional qualities of potato crops.
Source: Weidong Ru, Yuehan Pang, Yuanruo Gan, Qin Liu, Jinsong Bao, 'Phenolic Compounds and Antioxidant Activities of Potato Cultivars with White, Yellow, Red and
Purple Flesh', 2019, Antioxidants, 8, 419.