Encapsulation of vanilla extract by spray drying and spray chilling methods and its using in model food system

The aroma substances, which play an important role in the preference and consumption of foodstuffs, have attracted people's attention for centuries. Vanilla, one of these aroma substances, is of great commercial interest due to its natural structure and pleasant smell and taste. In this thesis, the vanilla extract obtained by natural means was microencapsuled by different methods without any chemical treatment. Classical and ultrasonic homogenizers were used to encapsulate the vanilla extract. For spray drying and spray chilling methods, the ratios of the combinations of coating materials and the ratios of vanilla extract/coating material were chosen as independent variables and experimental design was established with D-optimal composite design. In addition, the microencapsulation efficiency % values obtained as a result of the production according to the experiment design were selected as dependent variable and the optimization study was performed by targeting the highest amount of vanilla extract. The optimum coating material ratio were 83.2% maltodextrin and 16.8% whey protein isolate for spray drying; and 19.3% gum arabic and 80.7% palm stearin for spray chilling method. Although not being used as a response during the optimization phase, the amount of moisture content %, water activity, colour (L*, a*, b*), solubility, bulk density, tapped density, flowability, mean particle diameter, span, uniformity, glass transition and particle morphology features have also been examined in the thesis. Using of encapsulated vanilla extract powder in selected foodstuffs (ice cream, cake and pudding) and changing in storage of the selected pattern in the food (plain powder cake mixture) were also studied. Sensory evaluation of vanilla extract powder encapsulated at the optimum condition determined by semi-educated panelists of 10 person. The sensory evaluation scores of the selected food items were found high (p<0.05). Moreover, vanillin content of the samples produced at the optimum condition were analyzed during storage at 25°C for 8 weeks to follow the change of vanillin amount, and the degredation of vanillin were investigated.