Assessment of quality characteristics of fried zucchini slices, pre-dried with osmotic dehydration

In this study, it was aimed to investigate the quality characteristics of fried zucchini slices pre-dried using osmotic dehydration (OD) method at varying conditions (salt concentration, vacuum or ultrasound application, time). Textural properties (hardness, elasticity, cohesiveness, chewiness, firmness), surface color values (L*, a*, b*), moisture and oil content of the final product were determined. Textural properties did not change with OD applications (p>0.05). Vacuum and solution concentration applied during OD method had significant effects on surface color values (p≤0.05). OD did not cause any significant change in final moisture and oil content of the fried product. In case of ultrasound assisted osmotic dehydration (US-OD), it was seen that the effect of time on moisture content was important  the solution concentration of 5% (p≤0.05). On the other hand, changes at salt concentration have created significant differences in both the application process (p≤0.001). When solution concentration was 0%, effect of time was negligible to oil content (p>0.05). Notwithstanding, the solution concentration for both processing time was found to be significant (p≤0.05).

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