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The aim of this work was to determine phenolic acid and flavonoid contents, as well as antioxidant properties of propolis from different regions of Poland. Total phenolic content of propolis samples ranged from 150.05 to 197.14 mg/g GAE, while total flavonoid content was 35.64-62.04 mg/g QE. The dominant phenolic acid was p-coumaric acid, the content of which was from 37.54 to 116.95 mg/g. The samples also contained much ferulic acid. Among the flavonoids, chrysine and galangine were dominant, and for two samples, naringine was dominant. The propolis samples exhibited various antiradical activity measured towards DPPH(·) (1.92-2.69 mM TE/g) and ABTS(·+) (3.96-4.98 mM TE/g) and reducing power was determined by the ferric reducing antioxidant power method (6.23-9.19 mM Fe(II)/g). The significant linear correlations between total phenolic content and antiradical activity and between total phenolic content and reducing power were observed. Moreover, the total flavonoids content significantly correlated with antiradical activity and reducing power.

The phenolic components of honeys have great participation in their nutritional value and antioxidant activity. Moreover, phenolic components are promising markers for the determination of botanical and geographical origin of honey. The purpose of the present work was to study the antioxidant activity and profiles of phenolic acids and flavonoids of honeys of various origins. The total phenolic content of honeys varied from 4.46 to 15.04 mg of gallic acid equivalents per 100 g of product and the total phenolic acid content determined chromatographically varied from 201.05 to 2089.08 lg per 100 g of product. Buckwheat honey exhibited the highest antioxidant activity and contained the highest total phenolic amount, whereas rape honey exhibited the lowest values in this respect. Moreover, the buckwheat honey contained the highest amount of phenolic acids. There were significant linear correlations between total phenolic content and antioxidant activity of honey extracts in the reaction with DPPH • (1,1-diphenyl-2-picrylhydrazyl) and ABTS •+ (2,2¢-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) free radicals. In most samples, p-coumaric acid was the dominant phenolic acid (39.1-677.2 lg per 100 g). The honeys also contained considerable amount of gallic acid (6.0-913.8 lg per 100 g). Among flavonoids naringenin was predominant in the most studied honey samples.

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Selected physicochemical, thermal, and rheological properties of starches isolated from new Polish potato varieties were determined. The starches contained 25.7-30.0 g/100 g d.m. of amylose and 59.5-90.2 mg/100 g d.m. of phosphorus. Gelatinization temperatures were 62.6-64.0, 68.9-69.9, and 73.6-77.08C for T O , T P , and T E , respectively, whilst enthalpy of gelatinization amounted to 11.1-15.3 J/g. The retrogradation degree of starch was from 52.90 to 78.53%. Pasting curves showed significant differences between the starches. Peak viscosity and final viscosity ranges were 2035-4458 and 1931-2985 mPa Á s, respectively. Starch pastes exhibited non-Newtonian, shear thinning, and thixotropic behavior. After cooling they demonstrated diversified viscoelastic properties, however, all of them were classified as weak gels. Significant linear correlations among selected rheological parameters and amylose and phosphorus content were found. Results of principal component analysis demonstrated an ability to differentiate the starches isolated from different potato varieties.