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The aim of this study was to determine the polyphenols, glucosinolates and ascorbic acid content as well as antioxidant activity of beverages on the base of apple juice with addition of frozen and freeze-dried curly kale leaves. Upon enrichment with frozen (13%) and freeze-dried curly kale (3%), the naturally cloudy apple juice was characterized by an increase in phenolic compounds by 2.7 and 3.3-times, accordingly. The antioxidant activity of beverages with the addition of curly kale ranged from 6.6 to 9.4 μmol Trolox/mL. The obtained beverages were characterized glucosinolates content at 117.6–167.6 mg/L and ascorbic acid content at 4,1–31,9 mg/L. The results of sensory evaluation of colour, taste and consistency of apple juice and beverages with the addition of kale did not differ significantly prior to pasteurization (P ≤ 0.05), whereas after the pasteurization the evaluated factors decreased significantly. [ABSTRACT FROM AUTHOR]

We studied the content of tocopherols, tocotrienols and carotenoids in oil extracted from the kernels of 15 apricot ( Prunus armeniaca L.) genotypes and the associated oil yield of the studied samples. The oil yield in apricot kernels was in a wide range of 27.2-61.4% (w/w) dry weight basis. For each class of studied compounds (tocochromanols and carotenoids), a three-fold difference was found between the lowest and the highest content (78.8-258.5 and 0.15-0.53 mg/100 g of oil, respectively). γ-Tocopherol accounted for 91-94% of total tocochromanols detected in all tested samples. Lutein, zeaxanthin, β-cryptoxanthin and β-carotene were the main compounds among the eight different carotenoids detected in apricot kernel oils; they comprised 76-94% of the total carotenoids content, and compositions were characteristic for specific genotypes. The oil yield and content of lipophilic antioxidants in apricot kernel oils were significantly affected by the genotype. The oil yield was negatively correlated with the total amount of tocochromanols ( r = −0.910) and carotenoids ( r = −0.704) in apricot kernel oils. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare contents of biologically active compounds (ascorbic acid, phenolic compounds and glucosinolates) and antioxidant activity (ABTS assay) as well as sensory attributes of beverages based on apple juice with an addition of red cabbage added in the frozen (F) (17%), purée (Pu) (17%) or freeze-dried form (FD) (2%). The effect of thermal treatment (-P) of the product on the above mentioned parameters was analyzed. In the produced beverages the content of ascorbic acid was significantly lower than in apple juice. Contents of phenolic compounds increased from 3.1 to 4.9-fold (depending on the applied additive) in comparison to that in apple juice. A statistically significant correlation ( R 2 = 0.89) was observed between antioxidant activity and total contents of phenolics. In the tested beverages glucosinolates were found at amounts ranging from 149 to 171 mg/L. Thermal treatment caused a significant reduction in the levels of ascorbic acid and glucosinolates in all the tested products. In turn, phenolic contents decreased in F-P and FD-P (by 11% and 16%, respectively). The highest contents of investigated compounds were recorded in samples with an addition of freeze-dried red cabbage. All tested samples were found to be sensorially acceptable. [ABSTRACT FROM AUTHOR]

The aim of these studies was to investigate the influence of airborne ultrasound-assisted convective drying and microwave-assisted convective drying, as well as their combination, on process kinetics, total color change, water activity, content of carotenoids, polyphenols and antioxidant activity of carrots ( Daucus carota L.). The global model of drying kinetics based on coupled ordinary differential equations was used to describe the moisture and material temperature profiles during drying. Application of ultrasound and microwave in convective drying reduced drying time in the range of 9–81%, but the shortest drying time was observed for simultaneous action of convection, ultrasound and microwave. The results of qualitative analysis showed a product improvement due to ultrasound as compared to convective drying and microwave-convective drying. The proposed mathematical model of drying kinetics successfully simulated real drying processes. The proposed mathematical model of drying kinetics successfully simulated real hybrid drying processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The whole cranberry fruit was impregnated. • Ultrasound intensified the mass transfer during vacuum impregnation. • The degree of impregnation depends on the stage in which ultrasound was used. • No negative impact of vacuum impregnation on quality was observed. Combined vacuum impregnation and ultrasound was proposed as an alternative method to improve the infusion of ascorbic acid in berry fruit. The effect of ultrasound application at different stages of impregnation – vacuum, relaxation, and both stages – on the qualitative characteristics of impregnated cranberries was investigated. The quality assessment was based on porosity, color, antioxidant capacity, anthocyanin, polyphenol and structure compound content. Ultrasound-assisted vacuum impregnation contributed to higher ascorbic acid content, smaller relative color difference, and greater antioxidant properties. It was found that the degree of impregnation varies considerably and depends on the stage of using ultrasound. Due to more favorable quality attributes, the conclusion was reached that ultrasound should be applied during the relaxation stage of vacuum impregnation. [ABSTRACT FROM AUTHOR]