engleski

Apple fibers as delivery system of chokeberry phenolics

Dietary fibers are well known for their health benefits, therefore the potential for their use as delivery systems of chokeberry phenolics was investigated in this study. Particularly, adsorption of chokeberry phenolics on apple fibers was tested. For preparation of freeze-dried matrices, the content of chokeberry juice was constant and apple fiber content varied (2, 4, 6, 8 and 10%). Adsorption capacities of apple fibers for phenolics and anthocyanins were determined and expressed as mg of compound per g of fiber (mg/g). Adsorption capacity of fibers for phenolics decreased with the increase in fiber content, following a logarithmic trend (24.7, 11.5, 6.4, 4.6 and 3.7 mg/g, respectively for various fiber contents). With the increase in apple fiber content, the adsorption capacity for anthocyanins also decreased (1.85, 1.28, 1.00, 0.81 and 0.66 mg/g respectively). Color parameters of obtained freeze-dried matrices were also evaluated. The highest color change in comparison to fiber was obtained for 2% of fibers and with increasing fibers content, the associated color change decreased. Structural changes on fibers upon adsorption of phenolics were confirmed by FTIR and DSC analyses. FTIR spectra of loaded fibers had a peak at 1517 cm-1 while the spectra of fibers were missing it. Additional changes in FTIR spectra of loaded fibers was observed in the range of 1650 - 1600 cm-1 and at 1020 - 980 cm-1. In addition, DSC analyses indicated a slight increase in the melting point of loaded fibers.

apple fibers ; chokeberry phenolics ; color

nije evidentirano