Further Studies of Cavitation in the Homogenization of Milk Products

Abstract

Previous work by Loo, et.al., indicated that cavitation was a significant factor in homogenization. The exptl. work reported was divided into 2 parts, an examination of cavitation as a factor in homogenization and the design of a device for producing cavitation in milk products. Samples of milk from between the 1st and 2d stages of an exptl. homogenizer indicated that back pressures higher than 500 psi (lbs./sq. in.) reduced the homogenization efficiency. Exptl. homogenizer valves with tiny holes at various locations showed homogenization almost complete just beyond the inner edge of the valve. A valve with a seat narrowed to a knife edge homogenized both milk and concd, milk satisfactorily at a pump pressure of 800-1000 psi and a back pressure of 50 to 150 psi. Ice cream mix was not satisfactorily homogenized at similar pressures unless air at a saturation pressure of 75 psi was introduced into the mix. The air was believed to help overcome the inhibitive effect on cavitation of sugar and gelatin in the mix.