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U ovom radu ispitivan je utjecaj dodatka različitih količina (5, 10 ili 20%) disaharida (saharoza, maltoza ili trehaloza) na udio fenola, antocijana i antioksidativnu aktivnost liofiliziranih kaša od višanja. Rezultati su uspoređivani s rezultatima za kontrolni uzorak odnosno s liofiliziranom kašom od višanja bez dodatka šećera. Najveći udio antocijana imao je kontrolni uzorak. S povećanjem udjela šećera došlo je do smanjenja udjela antocijana, osim u uzorku s dodatkom 20% maltoze koji je imao najveći udio antocijana od svih uzoraka s dodanim šećerom. Udio fenola je također bio najveći u kontrolnom uzorku a najmanji u uzorku s dodatkom 20% trehaloze. Antioksidativna aktivnost je određena primjenom ABTS, DPPH i FRAP metode. Vrijednosti dobivene primjenom ABTS metode su niže od vrijednosti dobivenih DPPH i FRAP metodama. Najveću antioksidativnu aktivnost primjenom navedenih metoda imao je uzorak s dodatkom 20% maltoze. Rezultati ovog istraživanja pokazuju da interakcije unutar kompleksnog matriksa proizvoda utječu na udio fenolnih tvari i antioksidativnu aktivnost proizvoda. The aim of this research was investigation of the influence of different amounts (5, 10 or 20%) of dissacharides (sucrose, maltose or trehalose) on phenolics, anthocyanins and antioxidant activity of freeze-dried sour cherry puree. Results were compared with control sample, freeze-dried sour cherry puree without addition of sugars. The highest anthocyanin content had control sample. With increase of sugar addition, increase of anthocyanin content was observed except in the case of addition of 20% of maltose. That sample had the highest anthocyanin content among samples with sugar addition. The highest phenol content was also determined in control sample, while the sample with 20% of trehalose addition had the lowest content. Antioxidant activity was determined by ABTS, DPPH I FRAP methods. Values of antioxidant activity determined by ABTS were lower in comparison to values obtained by FRAP and DPPH method. The highest antioxidant activity (determined with all methods) had sample with addition of 20% of maltose. Results of this research showed that interactions among food component play important part on phenolics and antioxidant activity.

Brief introduction: The aim of this study was to evaluate the influence of freeze drying of sour cherry puree with sugars on phenolics and antioxidant activity (AOA) of the samples. Material and methods: Sour cherry purees were mixed with sugars (sucrose, trehalose or maltose) in the amount of 5, 10 or 20% and freeze-dried. Determination of phenolics, flavonoids, anthocyanins, percentage of polymeric colour and AOA was conducted and compared to results of freeze-dried puree. Results: The highest phenolic and anthocyanin content was determined in freeze-dried puree, 2.99 g/L and 408.70 mg/L, respectively. Freeze-dried samples with sugars had lower phenolic and anthocyanin contents. The highest phenolic content had samples prepared with 5% trehalose and 20% maltose, ~2.7 g/L, and the lowest with 20% of trehalose, ~1.9 g/L. The same samples had the highest anthocyanin content. Results of AOA highly depended on applied assay. Results of DPPH assay showed that all samples with sugars had higher AOA than freeze-dried puree, while in ABTS and FRAP assay all samples except sample with 20% of maltose had lower values of AOA. Conclusions: From obtained results it can be seen that sugar type and its amount had influence on the phenolics, anthocyanins and AOA.

The most important volatile compounds responsible for aroma profile of sour cherry are benzaldehyde, benzyl alcohol, 2-phenyl ethanol, eugenol, 2-hexenal, α-ionon and β-ionon. The aim of this study was to determine influence of disaccharides (sucrose, maltose and trehalose) and their amount (3.7%, 7.1% or 13.3%) on key volatile compounds (benzaldehyde, benzyl alcohol and 2-hexenal) of freeze-dried sour cherry puree. Sugars and their amount had influence on investigated volatile compounds. Control sample (freeze-dried sour cherry puree without sugar addition) contained 856.1 µg/kg of benzaldehyde, 3.92 mg/kg of benzyl alcohol and 15.58 µg/kg of 2-hexenal. Samples with addition of maltose (13.3%) and trehalose (7.1%) had the highest amount of benzaldehyde (871.34 and 937.51 µg/kg, respectively). In comparison to control sample, all samples with sugars addition had lower amount of benzyl alcohol. Among samples with sugar addition, the highest amount of benzyl alcohol had samples with addition of maltose (3.7%), 3.19 mg/kg, and all samples with trehalose addition, ~ 3.0 mg/kg. Samples with addition of maltose (13.3%) and trehalose (7.1% and 13.3%) had the highest amount of 2-hexenal (16.99, 17.45 and 18.96 µg/kg, respectively).