This study evaluated the total (Rt), reversible(Rrev), irreversible (Rirr), and cake (Rc) resistances duringmicrofiltration of watermelon juice (as a juice with colloidparticles) and red plum juice (as a juice without colloidparticles). Results showed that the total resistance decreasedby about 45% when the feed velocity was increased duringclarification of red plum juice due to change in cakeresistance. Also, increasing the feed temperature from 20 to30°C decreased the total fouling resistance by about 9%due to decreases in the irreversible and reversible foulingresistances. Also, mixed cellulose ester (MCE) membrane(which is hydrophilic) had a lower cake resistancecompared to polyvinylidene fluoride (PVDF) membrane(which is hydrophobic). Examination of the microfiltrationof watermelon juice showed thatRtdecreased by about54% when the feed temperature was increased from 20 to50°C, partially due to the reduction of reversible foulingresistance by 78%. Also, increasing transmembrane pres-sures from 0.5 to 2.5 bars greatly increased total foulingresistance. The feed velocity had a different effect onfouling resistances during microfiltration of watermelonjuice compared to red plum juice: in contrast with red plumjuice, increasing the feed velocity for watermelon juiceincreased cake resistance.
