Nutritivni profil i senzorski kvalitet voća i povrća osmotski dehidriranog u melasi šećerne repe i rastvorima saharoze / Nutritive profile and sensorial quality of osmotically dehydrated fruits and vegetables in sugar beet molasses and sucrose solutions

In this thesis, the osmotic dehydration of apple and carrot in sugar beet molasses and sucrose solutions, on temperature 55oC and atmospheric pressure, was studied. Effect of concentration of osmotic solution (sugar beet molasses - 80, 60 and 40oBx; sucrose solution - 70, 50 and 30oBx) and immersion time (1, 3 and 5 h ) on dry matter content (SM), water loss (WL) and solid gain (SG), change of mineral composition (K, Ca, Na, and Mg), the contents of sugars (sucrose, invert sugar), change the color and textural properties during osmotic dehydration of apple and carrot was investigated.It was found that increasing of process temperature, solution concentration and immersion time enhance mass transfer during osmotic dehydration of apple and carrot. Circulation of osmotic solutions, during the process, has intensified migration of water molecules from the treated plant material into the surrounding solution and penetration of dissolved substances molecules from the osmotic solution into the treated plant tissue.In addition, this thesis examines the effect of application of sugar beet molasses as osmotic solution, on the nutritional (mineral content and sugar) and sensory quality (color and texture) of apples and carrots during osmotic dehydration. In order to justify the use of molasses as an osmotic solution, the results obtained by osmotic dehydration of apple and carrot in sucrose and sugar beet molasses solutions, were compared. The results showed a significant improvement of the mineral content of apple and carrot dehydrated in sugar beet molasses solutions while the samples treated in sucrose solutions show significant reduction of the determinated mineral matters. Using sugar beet molasses showed better results when it comes to changes in the content of examined sugars (sucrose and invert sugar) because the increase in samples dehydrated in molasses was lower which is desirable result, from the aspect of osmotic dehydration process.The application of molasses as osmotic solution has a positive effect on the textural properties of apples and carrots compared with the results of the application of the sucrose solution. After 5h dehydration strength tissue was not significantly different compared to the control sample. Examination of the color of osmotic dehydrated apple and carrot samples was observed greater change the natural color of the treated plant tissue during dehydration in sugar beet molasses solutions compared to the results obtained during dehydration in sucrose solution. Depending on the final use of osmotic dehydrated semi-products / products that change the natural color of the samples can be considered as a positive result.Response surface methodology (RSM) was used in order to model mathematical dependence between system responses and examined factors (solution concentration and immersion time). Experiments were designed according to 23 full factorial experimental design with three factors each at three levels. For each response, second order polynomial models were developed and the polynomial coefficients were determined. Accuracy of the each model was checked by analysis of variance (ANOVA).