The influence of different carrier systems on encapsulation efficiency of dandelion (Taraxacum officinale l.) leaf polypehnols

U svrhu povećanja bioraspoloživosti, učinkovitosti i stabilnosti polifenolnih spojeva, posljednjih je godina sve veći interes znanstvenih krugova, ali i industrije, usmjeren na mikroinkapsulaciju biljnih polifenola. Cilj ovog rada bio je inkapsulirati polifenolne spojeve lista maslačka primjenom postupka ionskog geliranja. Kao nosač za inkapsulaciju korišten je alginat (A) te njegove kombinacije s izolatima proteina sirutke (IPS) te kakaovim prahom (KP), rogačem i zelenom kavom, kao novim materijalima za imobilizaciju aktivnih spojeva. Također, ispitan je utjecaj koncentracije alginata (4% i 5%) na inkapsulacijsku učinkovitost polifenola maslačka. Osim toga, formuliranim česticama ispitane su fizikalno-kemijske i morfološke karakteristike, inkapsulacijska učinkovitost i kinetika otpuštanja polifenola u simuliranim gastrointestinalnim fluidima. Veća koncentracija alginata rezultirala je većim česticama i njihovim sferičnijim oblikom te tvrđom, ali elastičnijom teksturom. „Jačanje“ alginatnog gela izolatima proteina sirutke i kakaovim prahom pokazalo je velik potencijal primjene tih prirodnih sirovina u svrhu inkapsulacije polifenola, budući da je najveća inkapsulacijska učinkovitost ukupnih polifenola i hidroksicimetnih kiselina ostvarena upotrebom sustava A-IPS, dok je najbolju kinetiku otpuštanja istih pokazao sustav A-KP.In order to increase the bioavailability, efficiency and stability of polyphenols, the scientific community and the industry have shown a higher interest for microencapsulation of plant polyphenols in the recent years. The aim of this study was to encapsulate the polyphenolic compounds of dandelion leaves using the method of ionic gelation. Alginate (A) and its combinations with new materials for immobilization of active compounds, such as whey protein isolates (WPI), cocoa powder (CP), carob and green coffee were used as encapsulation carriers. The influence of alginate concentration (4% and 5%) on the encapsulation efficiency of dandelion polyphenols was also examined. Furthermore, obtained hydrogel particles' physicochemical and morphological characteristics were examined, along with the encapsulation efficiency and release kinetics of polyphenols in simulated gastrointestinal fluids. The higher alginate concentration resulted in larger particles that had a more spherical shape and a harder texture. Reinforcement of alginate gel with whey protein isolates and cocoa powder showed a great potential for using those natural materials to encapsulate the polyphenolic compounds, since the highest rate of encapsulation efficiency of total polyphenols and hydroxycinnamic acids was accomplished using the A-WPI delivery system and the best release profile of total polyphenols and hydroxycinnamic acids was accomplished using the A-CP delivery system for encapsulation