Anthocyanins from pigmented potato (Solanum tuberosum L.) varieties

Pigmented potato (Solanum tuberosum L.) varieties are a rich source of anthocyanins, in particular acylated derivatives. From potato cultivars "Hermanns Blaue", "Highland Burgundy Red", "Shetland Black", and "Vitelotte" the major anthocyanins were isolated and characterised. Sliced potatoes were blanched to minimise enzymatic reactions which cause degradation of anthocyanins. By means of solid phase extraction, countercurrent chromatography and preparative HPLC, it was possible to separate coumaric acid derivatives (i.e. 3-p-coumaroylrutinoside-5-glucosides of petunidin, pelargonidin, peonidin and malvidin) from non-acylated anthocyanins as well as chlorogenic acids. Identity of the isolated compounds was determined by combination of HPLC-DAD and LC-ESI-MS2 measurements. Petunidin derivatives were detected in all varieties except Highland Burgundy Red, where pelargonidin was found to be the only anthocyanidin. Malvidin was the predominant aglycon of the variety Vitelotte. Of the four selected cultivars, Shetland Black was the only one containing minor amounts of peonidin derivatives. (c) 2005 Elsevier Ltd. All rights reserved.