DOI: 10.5937/FFR1701023B UDK 547.915:678.71:664 Original research paper ENCAPSULATION OF RESVERATROL IN SPHERICAL PARTICLES OF FOOD GRADE HYDROGELS Bojana D. Balanč *1 , Kata T. Trifković 1 , Radoslava N. Pravilović 1 , Verica B. orđević 1 , Smilja B. Marković 2 , Viktor A. Nedović 3 , Branko M. Bugarski 1 1 University of Belgrade, Faculty of Technology and Metallurgy, Department of Chemical Engineering 2 Institute of Technical Sciences of the Serbian Academy of Sciences and Arts 3 University of Belgrade, Faculty of Agriculture, Department of Food Technology and Biochemistry *Corresponding author Tel.:+381 11 3370471 Fax: +381 11 3370387 email: bisailovic@tmf.bg.ac.rs ABSTRACT: The paper reports about the preparation and characterization of hydrogel particles containing liposomes loaded with resveratrol as an active compound. The materials used for preparation of the particles were chosen to be suitable for food industry. Different polymer concentrations affect particles shape, size, size distribution, as well as the release kinetics of resveratrol. The diameter of particles varied from 360 to 754 µm, while the narrow size distribution was observed for all types of particles. Release studies were performed in Franz diffusion cell and the results showed the prolonged release of resveratrol from all samples, but the sample with the highest content of polymer (2.5% w/w) in particular stood out. The research provides useful information about liposomes containing active compound encapsulated in hydrogel matrices and offers the basis for its application in the food industry. Key words: resveratrol, sodium alginate, release, sphericity, particles INTRODUCTION Resveratrol is a natural antioxidant with remarkable antioxidant activity, found in grapes and red wines (Stojanović et al., 2001, Lim et al., 2014). It is also highly sensitive compound and poorly soluble in water surrounding (Lopez-Nicolas et al., 2006; Pineiro et al., 2006). Therefore, its application is uncommon although resver- atrol possesses strong antioxidant pro- perties. Nowadays, functional food with addition of highly valuable antioxidants attracts attention of both, consumers and producers, as well as researchers (or- đevic et al., 2015). In order to use sensitive antioxidants in functional food products it is necessary to protect them in a certain way. For that purpose, encap- sulation techniques are found to be con- venient (Belščak-Cvitanović et al., 2011; Stojanović et al.,2012; orđevic et al., 2015; Istenič et al., 2015) and among them electrostatic extrusion stands out as non-invasive one. In addition, it has been demonstrated that particles obtained via electrostatic extrusion technique have very narrow size distribution (Bugarski et al., 2004), which is important from the ap- plication aspect. Unfortunately, due to poor solubility of resveratrol in water, its direct encapsulation in hydrogel particles is not possible. As it was described by Isailović et al. (2013) resveratrol can be 23