Fizičko-hemijska i reološka karakterizacija mikrokapsula ribljeg ulja inkorporiranih u čokoladni matriks

Abstract

Omega-3 masne kiseline su uslovne za zdravlje ljudi i imaju značajne fiziološke uloge. Dijetetski proizvodi na bazi omega-3 masnih kiselina predstavljaju značajan izvor omega-3 masnih kiselina. Riblje ulje je dobar izvor polinezasićenih masnih kiselina (PUFA). Dnevni unos omega-3 polinezasićenih masnih kiselina je u većini delova sveta ispod preporučenog, uglavnom usled nedovoljne zastupljenosti ribe u ishrani. Zbog toga se danas riblje ulje nalazi u obliku različitih dijetetskih proizvoda i ponuda ovih preparata na tržištu je veoma široka. Problem sa unosom ribljeg ulja kao dodatka ishrani je njegov intenzivan i neprijatan ukus i miris, što može da dovede do neadekvatne suplementacije. Sušenje raspršivanjem (engl. spray drying) predstavlja tehniku koja omogućava trenutno sušenje rastvora, suspenzija ili emulzija. U pitanju je metoda koja ima široku primenu u farmaceutskoj industriji, a između ostalog se primenjuje i u cilju maskiranja neprijatnog ukusa lekova. Kao omotač mikrokapsula dobijenih sušenjem raspršivanjem je moguće koristiti proteine, ali je neophodno dobro ispitati i poznavati njihove fizičko-hemijske osobine i funkcionalnost. Inkorporiranjem mikrokapsula ribljeg ulja u čokoladu bi se dobila funkcionalna ili obogaćena hrana, što predstavlja i finalnu formulaciju u ovom radu. Obogaćivanjem čokolade sa visokim sadržajem kakao delova mikrokapsulama ribljeg ulja kreirao bi se višestruko funkcionalan proizvod. Odabir čokolade kao matriksa za obogaćivanje uslovljen je činjenicom da je ona široko konzumiran proizvod. Ciljevi ovog rada bili su da se ispita uticaj metode sušenja raspršivanjem na stabilnost preformulacije ribljeg ulja, da se utvrde karakteristike mikrokapsula dobijenih sušenjem raspršivanjem (prinos i efikasnost mikrokapsulacije, oksidativnu stabilnost ulja, morfološke osobine i veličinu mikrokapsula), zatim da se utvrdi uticaj veličine čestica na kristalizaciju u masnoj fazi suspenzije koja se koristi za izradu konditorskih proizvoda i da se utvrde fizičko-hemijske karakteristike (teksturu, boju, reološke osobine) čokolade koja sadrži inkorporirane mikrokapsule ribljeg ulja u odnosu na čokoladu bez dodatka mikrokapsula. Metode su obuhvatale karakterizaciju proteina dobijenih iz soje, graška, krompira, pirinča i surutke, njihovih rastvora, kao i emulzija ribljeg ulja u vodenim rastvorima tih proteina, određivanje prinosa i efikasnosti mikrokapsulacije i karakterizaciju dobijenih mikrokapsula. Prilikom ispitivanja uticaja veličine čestica na kristalizaciju u masnoj fazi suspenzije koja se koristi za izradu konditorskih proizvoda i fizičko-hemijskih osobina čokolade koja sadrži inkorporirane mikrokapsule ribljeg ulja primenjivane su metode za određivanje teksture, reoloških karakteristika, sadržaja čvrstih masti i boje dobijenih formulacija. Dobijeni rezultati su pokazali da se proteini ponašaju kao dobri emulgatori i da sušenje raspršivanjem predstavlja efikasan način za dobijanje mikrokapsula ribljeg ulja sa proteinima kao omotačima mikrokapsula. Kristalizacija masne faze u suspenziji koja predstavlja model čokolade zavisi od veličine čvrstih čestica. Kada je u pitanju proizvodnja čokolade sa inkorporiranim mikrokapsulama ribljeg ulja kod kojih su kao omotači korišćeni proteini soje, surutke i krompira, dodatak tih mikrokapsula ne utiče na karakteristike čokolade u meri dovoljnoj da bi se narušio proizvodni proces izrade. Sve navedeno upućuje na zaključak da bi proizvodnja čokolade sa inkorporiranim mikrokapsulama ribljeg ulja, tehnološki bila moguća.

Omega-3 fatty acids are essential for human health and have significant physiological roles. Dietary products based on omega-3 fatty acids are a significant source of omega-3 fatty acids. Fish oil is a good source of polyunsaturated fatty acids (PUFA). The daily intake of omega-3 polyunsaturated fatty acids is below the recommended level in most parts of the world, mainly due to the lack of fish in the diet. This is why fish oil is now found as various dietary products which are widely present in the world’s market. The problem with fish oil intake as a dietary supplement is its intense and unpleasant taste and odor, which can lead to inadequate supplementation. Spray drying is a technique that allows instantaneous drying of solutions, suspensions or emulsions. It is a widely used method in the pharmaceutical industry and is used, among other things, to mask the unpleasant taste of medicines. It is possible to use proteins as a coating of spray-dried microcapsules, but it is necessary to test and know their physicochemical properties and functionality. Incorporating fish oil microcapsules into chocolate would make functional or enriched foods, which is consider as a final formulation in this work. Enriching the high cocoa content chocolate with fish oil microcapsules would create a multi-functional product. The choice of chocolate as a base is conditioned by the fact that it is a widely consumed product. The aim of this study was to investigate the effect of spray drying method on the stability of fish oil pre-formulation, to determine the characteristics of microcapsules obtained by spray drying (yield and efficiency of microencapsulation, oxidative stability of oil, morphological properties and size of microcapsules), to determine the effect of particle size crystallization in the oil phase of the suspension used for confectionery products and to determine the physicochemical characteristics (texture, color, rheological properties) of chocolate containing fish oil microcapsules in comparison with chocolate without the addition of microcapsules. Methods included characterization of proteins obtained from soybeans, peas, potatoes, rice and whey, their solutions, as well as fish oil emulsions in aqueous solutions of these proteins, determination of the yield and efficiency of microencapsulation, and characterization of the microcapsules obtained. In the examination of the effect of particle size on crystallization in the oil phase of the suspension used for the manufacture of confectionery and physicochemical properties of chocolate containing fish oil microcapsules, methods were used to determine the texture, rheological characteristics, solid fat content and color of the formulations obtained. The results show that proteins act as good emulsifiers and that spray drying is an effective way to obtain fish oil microcapsules with proteins as microcapsule shells. The crystallization of the oil phase in the suspension representing the chocolate model depends on the size of the solid particles. In the case of production of chocolate with incorporated fish oil microcapsules using soybean, whey and potato proteins as coating material, the addition of these microcapsules does not affect the chocolate characteristics to a degree sufficient to impair the manufacturing process. All of the above points to the conclusion that the production of chocolate with incorporated fish oil microcapsules would be technologically possible.