2.4.1. Total Polyphenol Content

Total polyphenol content (TPC) was determined according to the method of Turkmen et al. [23] and Koivikko *et al.* [24] with slight modifications. For rye snacks, 100 mg was dissolved in 10 mL water to obtain a 10 mg/mL solution. Briefly, 20 μL of sample was mixed with 100 μL of 0.2N Folin-Ciocalteu phenyl reagen<sup>t</sup> and allowed to stand at room temperature for 5 min. Then, 80 μL of 7.5% Na2CO3 was added and the solution was incubated for 10 sec at 800 W in microwave and put on a shaker for 30 min at room temperature. Absorbance was read at 720 nm with a microplate reader (POLARstar Optima BMG labtech, O ffenburg, Germany). Phloroglucinol was used as a standard, and the results are expressed as gram of phloroglucinol equivalents (PGE) per 100 g of extract.
