The effects of varying the rennet concentration (by a factor of 216) and the coagulation method on the texture of 32 Feta cheeses produced from ultrafiltered milk were examined by rheological, sensory and chemical methods. Cheeses were obtained that varied greatly in texture but had the same gross chemical composition. All rheological measurements (uniaxial compression, strain sweep and relaxation measurement), sensory firmness and chemical measures of proteolysis depended significantly on the rennet concentration used. With increasing rennet addition, the cheeses became firmer and grittier, and less adhesive and sticky. With two of the three coagulation methods, the physicochemical state of the casein micelles at the point of coagulation varied with the rennet level: when less rennet was used, coagulation occurred at a lower pH and after longer contact between milk and NaCl. However, the effects of increased rennet concentration were also significant with the third method, where there was no effect on the pH or the period with NaCl at coagulation. Probably the primary effect observed was that an increased aggregation rate, with increased rennet level, affected the initial mode of aggregation of casein particles, leading to a denser network structure and a firmer and grittier texture. The level of micellar disintegration at coagulation (controlled by the coagulation method used) had a supplementary effect.