Some dried fruits from Rosaceae family plants and fresh Aronia melanocarpa fruits were studied for contents of benzoic and cinnamic acid derivatives by gas chromatog./ mass spectroscopy. In the dried chokeberry fruits, the contents of the acid derivatives except for cinnamic acid were lower than 1 mg/100 g of dried fruits. In other fruits, contents of the acids were higher than 4 mg/100 g of dried fruits. The short-period freezing of the fruits had no impact on chokeberry polyphenol content. The fast drying resulted in a significant decrease in polyphenol content.