Magnetic resonance imaging was an effective means for visualizing moisture profiles during drying of starch molded confectionery, and clearly demonstrated the importance of moisture transfer between the confectionery gel and the molding starch. Rapid formation of a very dry "skin" was observed that resulted in case-hardening. Drying was effectively diffusion controlled after the first 30 min. Moisture profiles within the porous bed of molding starch, where total proton density is low and T2* is short, were visualized using single point ramped imaging with T1 enhancement (SPRITE). Similar images were not possible using more traditional spin-echo techniques. The long component of a bi-exponential T1 was linearly related to the solids content, and T1-null images were constructed to visualize iso-solids contour lines.
All Science Journal Classification (ASJC) codes
- Food Science