Comparative Evaluation of Four Homogenization Machines

Microbiological examination of foods involves sample preparation and subsequent homogenization.This paper addresses the effectiveness of Stomacher,Pulsifier,Bagmixer and Smasher instruments in terms of: 1) viable cell counts/g for 10 kinds of foods,2) noise level of four instruments associated with human operation and decibel meter at 5 ft from each instrument,3) convenience for cleaning instruments after use,and 4) ergonomics.Aliquots of 25 g for 10 kinds of foods were placed individually in a sample bag containing 224.5 mL of 0.1% peptone water plus 0.5 mL of Escherichia coli inoculum.Each food was homogenized for 60 s.Ease of cleaning and ergonomics when using Stomacher were determined as a reference.All 4 instruments revealed a similar performance regarding viable cell counts.As for noise level,Smasher and Bagmixer were the quietest,followed by Stomacher and Pulsifier.Smasher ranked highest in ease of cleaning and ergonomics,followed by Bagmixer,Stomacher,and Pulsifier.