The study evaluated the effect of packaging pasteurised milk inside an ISO Class 8 cleanroom and an external Class 7 antechamber. Chemical, microbiological and sensory analyses of three trials did not show evidence of improvements in the product shelf life, although the total airborne particle and the viable airborne counts were considerable higher outside the cleanroom than inside it. Post-pasteurisation contaminations inherent to the equipments should be considered in futures studies. Therefore, the use of cleanroom technology is an operational alternative to be taken into consideration, provided that the characteristics of the whole system is compatible with the high standards of the clean air.632266272