Characterisation of five potato cultivars according to their nutritional and pro-health components.

BACKGROUND

Potatoes are very popular vegetables in Poland, not only in terms that they are easy to prepare, but also by the fact that they combine the wholesomeness of cereals and delicacy and characteristic chemical composition of vegetables, so it is important that they find their place in our diet. Nutritional value of potatoes is determined by the content of nutrients such as protein, starch, fat, minerals, and absence of toxins, as well as by a significant content of bioactive components from the group of polyphenols, which guarantee proper antioxidant activity of this vegetable. The study was performed in order to analyse 5 Polish potato cultivars, according to nutritional components, i.e.: proteins, fat, starch, carbohydrates, ash and biologically active compounds: such as polyphenols, flavonoids, as well as dietary fibre. At the same time antioxidant activity of the cultivars was determined by means of two independent methods.

METHODS

The material for the study consisted of five varieties of potatoes: Saturna, Hermes, Raja, Rosalind, Courage, which were analysed for the content of nutrients i.e. protein, fat, starch, carbohydrate, ash and biologically active compounds: polyphenols, flavonoids, and fiber. Antioxidant activity of the examined potato varieties was determined by two independent methods.

RESULTS

It was shown, taking into account the nutrients, that the potato variety Raja was characterised by the lowest content of carbohydrate and ash, and high amounts of protein and fat. The highest content of insoluble dietary fibre was determined for Raja, and its soluble fraction for Saturna. The amounts of insoluble fibre were three times as much as the content of soluble fibre in the analysed potato cultivars. The highest total polyphenol content was measured for Saturna, and the lowest for Rosalind. Other cultivars revealed similar amounts of these components (3 mg catechin/g d.m.). The contents of flavonols and flavonoids was not proportional to total polyphenol content in the analysed potato cultivars. Antioxidant activity determined by two independant methods was proportional to total polyphenol content in the analysed plant material.

CONCLUSIONS

It was shown that the content of pro-health ingredients such as: dietary fiber, total polyphenols and antioxidant activity was preferable for two of the five examined varieties of potatoes: Saturna and Raja.