Purple-fleshed potatoes

This subject has been treated comprehensively in Chapter 3. Colorful potatoes have been suggested as potential sources for food colorants,and the major anthocyanin of the purple-fleshed potato Congo, petanin, shows higher color stability than simple anthocya-... 

Reyes, L. F., Cisneros-Zevallos, L. (2003). Wounding stress increases the phenolic content and antioxidant capacity of purple-flesh potatoes Solanum tuberosum L.). J. Agric. Food Chem., 51, 5296-5300. 

Kita, A. Bakowska-Barczak, A. Hamouz, K. Kulakowska, K. Lisinska, G., The effect of frying on anthocyanin stability and antioxidant activity of crisps from red- and purple-fleshed potatoes (Solanum tuberosum L.). Journal of Food Composition and Analysis (2013) 32, 169—175. 

The colors and stabilities of anthocyanin extracts from purple- and red-flesh potatoes were less affected by pH and temperature than commercial concentrates of... 

Reyes, L.R and Cisneros-ZevaUos, L., Degradation kinetics and colour of anthocyanins in aqueous extracts of purple- and red-flesh potatoes Solanum tuberosum L.), Food Chem., 100, 885, 2007. 

Tomoyuki, O. et al., Determination of acylated anthocyanin in human urine after ingesting a purple-fleshed sweet potato beverage with various contents of anthocyanin by LC-ESI-MS/MS, Biosci. Biotechnol Biochem., 70, 2540, 2006. 

Reyes, L. F., Miller, J. C. J., Cisneros-Zevallos, L. (2004). Environmental conditions influence the content and yield of anthocyanins and total phenolics in purple- and red-flesh potatoes during tuber development. Amer J Potato Res, 81,187-193. 

A study of 74 Andean potato landraces found about an 11-fold variation in total phenolics and a high correlation between phenolics and total antioxidant capacity (Andre et al., 2007a). We screened tubers from hundreds of cultivars and wild potato species for phenolics and found over a 15-fold difference in the amount of phenolics in different potato genotypes. Many phenolics are colorless, and thus are relevant phytonutrients for white-fleshed cultivars, which are the consumer-preferred t5q)e of potato in many countries. Russet Norkotah has high amounts among the white-fleshed cultivars, about 4 mg/g DW. S. Pinnatisectum, a purple-fleshed wild species. 

Furatu, S., Suda, I., Nishiba, Y., and Yamakawa, O. 1998. High tert-butylperoxyl radical scavenging activities of sweet potato cultivars with purple flesh. Food Sci. Technol. Int. Tokyo 4, 33-35. 

It has been reported that white, yellow, orange, and purple-fleshed sweet potato cv. have antioxidative and radical-scavenging activities, with the purple... 

Dihydroxy-E-cinnamoyl) 6-0-Caffeoylsophorose C21H28O14 504.444 Isol. from red vinegar by fermented purple-fleshed sweet potato (Ipomoea batatas). a-Glucosidase inhibtitor. Antioxidant. 

Pharmacokinetics. Recently, it has been shown that human urine of 87 volunteers after ingestion of a purple-fleshed sweet potato beverage contained peonidin 3-caffeoylsophoroside-5-glucoside. Absorption of this compound into the bloodstream of rats and presence as an intact acylated form in their plasma has been demonstrated previously (Oki et al. 2006 and references therein). Urinary excretion of anthocyanins is usually low due to metabolization. 

Suda, L, Oki, T., Masuda, M., Kobayashi, M., Nishiba, Y., Fumta, S. 2003.Physiological functionality of purple-fleshed sweet potato containing anthocyanins and their utilization in foods. Japan AgriculturalResearchhl, 167- 173. 

Cevallos-Casals, B.A. and Cisneros-Zevallos, L., Stability of anthocyanin-based aqueous extracts of Andean purple corn and red-fleshed sweet potato compared to synthetic and natural colorants. Food Chem., 86, 69, 2004. 

Potatoes are annual vegetables grown for their nutritious, starchy tubers. They are commonly known as white potatoes, but different cultivars have white, yellow, pink, or even bluish flesh, and yellow, brown, red, or purple skin. 

Leaves with purple-bordered yellow spots. Cause Internal cork. Destroy infected plants. See Potatoes with hard, dark, corky spots in the center of flesh" below for controls. 

Solanum tuberosum L. Carotenoids, predominantly xanthophylls such as lutein, zeaxanthin, violaxanthin, only traces of carotenes, are present in the flesh of all potato cultivars. However, there are large quantitative differences White-fleshed varieties were determined to contain 50-100 pg/lOOg fresh weight, whereas yellow- to orange-fleshed ones may contain up to 2000 g/100g fresh weight. The colour of red and purple potatoes is caused by anthocyanins (Brown 2005 and references therein). 

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