This experiment investigated the impact of liquid viscosity on the effectiveness of ultrasonication treatment. It was hypothesized that the percentage of bacteria inactivated through ultrasound for liquids of different viscosity measurements would increase as the viscosity of the liquid increased. Through the marble drop method, the viscosities of three different liquids: maple syrup, glycerin, and light corn syrup were determined. E. coli was mixed into 125 mL of each liquid, and a sample of each was taken at spread evenly onto a nutrient agar plate prior to treatment. Then, the liquids were submerged in an ultrasonic bath for 480 seconds. After this cycle was completed, four samples of each liquid was taken and spread evenly onto separate agar plates. The agar plates were then incubated for 24 hours at 37°C. After incubation, they were removed, and the number of bacterial colonies on each of the plates was counted. The viscosities of maple syrup, glycerin, and light corn syrup were measured to be 0.12 mPa-s, 0.482 mPa-s, and 4.34 mPa-s, respectively. The percentage of bacteria inactivated for the three liquids in the same order was -40%, 99.9%, and 99.7%. There appeared to be no correlation between the viscosity of the liquid treated and the percentage of bacteria inactivated. In determining the ultrasound treatment length required for liquid food products, viscosity does not seem to be a property that requires significant consideration.