How can we keep glaze from melting in fruit bread? The bread contains a lot of moist fruit whose moisture migrates to the surface, causing the glaze to melt.
Try adding some gum in your glaze like sodium carboxymethylcellulose from .0.1 to 0.3% .
Do you put the glaze before going to the oven? At certain temperatures, the oven’s temperature may remove the intimately linked water that exists in the glaze. Afterwards it will catch up the water from the atmosphere and it disappears. It happened to me with powdered sugar in a pastry product.
You can always coat the fruit (crystallized fruit) so the water does not migrate to the glaze.