Viscosity Reduction by Homogenization of Orange Juice Concentrate in a Pilot Plant Taste Evaporator

Abstract

Controlling viscosity is critical to efficient evaporation and pumping of citrus concentrates. Viscosity was reduced by a commercial homogenizer installed between the third and fourth stage of a pilot plant TASTE evaporator. Juice was concentrated to 65"Brix with and without homogenization. The results showed a 13% decrease in viscosity due to homogenization. Mean non-homogenized values were 279 mPa.s (s.d. = 7.5) on the 65"Brix control and 242 mPa.s (s.d. = 10) on the homogenized concentrate, both measured at 3.50 set', which was calculated to be the shear rate for these samples within the third stage of this evaporator. This decrease in viscosity also reduced the energy consumption about 3 to 4% or produced a higher (2 to 3) "Brix concentrate. Homogenization did not significantly affect the juice color, acid, pulp or vitamin C.

Inactivation of pectin methylesterase and stabilization of opalescence in orange juice by dynamic high pressure

“…To remain in suspension in a solution having the specific gravity of orange juice, particles of such composition must be of a size ranging from 0.5 to 10 lm (Mizrahi & Berk, 1970). It has been demonstrated for both orange and passion fruit juices that physical and mechanical forces present during homogenization increase the proportion of small particles and slightly improve juice stability and opalescence (Crandall & Davis, 1991;Crandall et al, 1988;Okoth, Kaahwa, & Imungi, 2000). Our results, shown in Figs.…”

“…This treatment differs from static high pressure by introducing rheological phenomena such as cavitation, friction, shear and turbulence. Homogenization brings about physical changes which reduce the viscosity of concentrated orange juice (Crandall & Davis, 1991;Crandall, Davis, Carter, & Sadler, 1988;Floury, Desrumaux, Axelos, & Legrand, 2002) probably by acting on macromolecules such as proteins and polysaccharides (Corredig & Wicker, 2001;Floury et al, 2002;Paquin, Lebeuf, Richard, & Kalab, 1993). Clark et al (1993) found that DHP treatment at 15 000 psi (about 100 MPa) was effective at decreasing microbial activity in orange juice.…”

Rheological Characterization of Ketchup

“…5 ) , can be attributed to many factors. These factors include the heterogeneity of the materials constituting the products (Leoni et al 1984), the difference in the product formulation between cold and hot breaks (these last generally show a wide range of viscosity as reported by De Sio et al 1986), the different homogenization degree (Kertesz and Locoonti 1944;Crandall and Nelson 1975;Crandall et al 1988;Castaldo et al 1990) and finally the difference among the products in their pectic content (Luh and Daoud 1971).…”

The Chemical Engineering Design of a Commercial Citrus Evaporator for the Production of 6,539.86 kg/hr Orange Juice Concentrate in Lagos, Nigeria, West Africa

“…Crandall et al [15] explored the prerequisite of a proficient methodology for viscosity decrement by inaugurating a commercial homogenizer between the third and fourth stages of a pilot plant TASTE evaporator. They contended that viscosity control was clamorous for effectual evaporation and vacuation of citrus concentrates.…”