You should add some mild detergent such as Tween 20 to your culture media in tiny proportions to get rid of this.

Thank you very much for your response.

Herein, you may find another solutions for dispersing MAP clumps:

1) Vortexing the MAP suspension with glass beads (3 mm) for 40 seconds

2) Homogenizing the MAP suspension by ribolyzer using glass beads for 4 cycles of 45 s at 4 m/s.