Abstract: In the phyto-chemical research of extracts, there is a rising demand for simple, quick, selective and precise quantitative analysis methods of polyphenolics. The goal of this research was to realise a quantitative meta-analysis of the experimental methods that investigate flavonoids from three types of seeds of Lens culinaris Medikus extracts using spectrophotometry. Polyphenol quantitative determination was done through spectrophotometric methods (based on the chelating reaction with AlCl3/CH3COONa for flavones, and Arnow reaction for poliphenolcarboxylic acids). Determination of the antioxidant activity of the extract was realised with the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method and ORAC (antioxidative capacity of the oxygen radical) method. The antioxidant capacity of the analysed extracts is proportional with their concentration value. In order to use as nutraceuticals, the organic solvents were replaced with alimentary ethanol of fermentative origin, and HCl was replaced with acetic acid of 0.5% concentration.