In the present study, gelatine - based hydrocolloids with glass microbubbles were designed and investigated as potential tissue mimicking materials for adipose and lung tissues in Computed tomography. Hydrocolloids contained 0.04 or 0.08 g mL-1 gelatine and glass microbubbles in the range 0.04 - 0.28 g.mL-1. Hounsfield units were derived for voltages in the range 70 - 120 kVp. All obtained values were negative with limits from about - 10 HU to about -445 HU. Mechanical performance was also investigated, giving comparatively high Young’s modulus up to about 1.2 MPa. Hounsfield units’ further decrease might be possible by 3D printing of the hydrocolloids, when printed with a speed from 60 to 90 mL h-1, at a minimum temperature of 40 oC. Printability is limited up to 0.20 g mL-1 glassmicrobubbles concentration.