Effect of ultrasound pre-treatment and drying method on specialized metabolites of honeyberry fruits (Lonicera caerulea var. kamtschatica).

• USN pre-treatment and vacuum-drying were applied to dry honeyberries. • The rate of moisture loss was modeled during drying. • The model fitted reasonably well the data obtained from vacuum-assisted drying. • USN pre-treatment significantly reduced the loss of specialized metabolites. • The drying time was reduced by combining USN pre-treatment with vacuum-drying. Honeyberries are rich in various nutrients (eg. minerals, and vitamins) and bioactive compounds (eg. polyphenols). The aim of the study was to evaluate the impact of ultrasound (USN) pre-treatment (100% power at 37 kHz) at 40 °C for 3 min and drying techniques (conduction or vacuum) on nutritional composition and bioactive compounds of honeyberry fruits. The evaluation of dried barriers revealed that both USN pre-treatment and drying techniques affected the composition of the final product. The highest vitamin C content (1.067–1.187 mg 100 g−1 DM) was found in fruit samples pre-treated by USN, regardless of the drying technology used. The highest total phenol (2.445 mg GAE 100 g−1 DM), total flavonoid (0.939 mg GAE 100 g−1 DM), total non-flavonoid (1.506 mg GAE 100 g−1 DM) and anthocyanin content (2.334 mg kg−1 FW) were obtained in fruits after applying USN pre-treatment and vacuum dried at 40 °C. [ABSTRACT FROM AUTHOR]