Its been couple of days since i have not found the solution for this. As there is an option for mat-menu that is overlaptrigger property but there is no property to perform
I've found the solution as disableOptionCentering direcrive for mat-select, so after using this dropdaown can be customized.
from timmoy: https://github.com/angular/material2/pull/9885
Example usage:
{{ creature.viewValue }}