OPTIMIZATION OF DEHYDRATED EGG QUALITY BY MICROWAVE-ASSISTED FREEZE-DRYING AND HYDROCOLLOID INCORPORATION

Enhancement of the physical and sensory properties of rehydrated egg p roducts as a consequence of microwave assisted freeze-drying and addit ion of hydrocolloids to the formulation was assessed. When compared to conventional freeze-drying (CFD), microwave assisted freeze-drying (M FD) led to products with greater water-holding capacity and reduced el astic modulus. Comparisons were also made of moisture sorption rates. The addition of xanthan gum and, to a lesser extent, microcrystalline cellulose increased both water-holding capacity and elastic modulus. M agnitude estimation by a trained texture panel of critical sensory pro perties (chewiness, rubberiness, moistness, moisture release, and roug hness) revealed that MFD samples were superior to CFD samples and that MFD samples containing xanthan were closest to the ''optimal'' for th e egg products. It was concluded that the more uniform and less heat s tressing process of microwave assisted freeze-drying coupled with the presence of xanthan gum leads to a rehydrated product that best retain s its structural.