Background. Nutritive value of food is determined by its 
content of basic nutrients essential for the proper functioning of the human 
organism. Buckwheat grain is one of the most valuable raw materials for 
production of groats as well as functional food. It is characterized by high 
contents of starch, protein as well as dietary fibre. Apart from the above 
mentioned nutrients, buckwheat groats contain flavonoid compounds, playing the 
role of antioxidants. The aim of this study was to 
determine contents of dietary fibre and its fraction composition, thiamine and 
phenolic compounds in roasted buckwheat groats, as well as antioxidant 
properties of ethanol buckwheat groats extracts. 
Material and 
methods. Experimental material comprised roasted 
buckwheat groats purchased at a grocery shop. Contents of neutral detergent 
dietary fibre (NDF) and its fractions were determined by the detergent method 
according to Van Soest. Thermostable a-amylase 
(Termamyl 120 
L) was used in the digestion of starch. Contents of total 
dietary fibre (TDF), soluble dietary fibre (SDF) and insoluble dietary fibre 
(IDF) were determined according to Asp et al. The content of thiamine was 
determined by the thiochrome method. Total polyphenol content was determined by 
colorimetry according to the Folina-Ciocalteu method. Antioxidant properties of 
extracts were estimated based on the capacity of extracts to scavenge the 
DPPH• radical (1,1-diphenyl-2 picrylhydrazyl) and towards linolic 
acid. The capacity to inhibit self-oxidation of linolic acid was determined 
according to Lingnert et al. 
Results. The NDF and TDF contents in buckwheat groats, amounting to 5.63 and 
8.4%, respectively. The fraction found in biggest amounts was the hemicellulose 
fraction (3.42%). The level of the IDF fraction was much higher (5.94%) than 
that of SDF (2.46%). Thiamine content was 0.519 mg/100 g product, while 
the total content of phenolic compounds extracted from buckwheat groats 
was 30.592 µg·cm-3. Ethanol extract of buckwheat groats was 
characterized by a high DPPH• radical scavenging capacity 
(80.8%) and exhibited high capacity to inhibit self-oxidation of linolic acid 
W0 = 0.86. 
Conclusions. 
Investigations showed that buckwheat groats, widely used in Polish diet, due to 
their content of biologically active substances, may be a raw material for the 
production of functional food.