Reduction of Salt (NaCl) Losses During the Manufacture of Cheddar Cheese

The objective of this study was to evaluate the effects of various cheese making technologies, i.e., homogenization of cream, ultrafiltration and vacuum condensing of milk, on the retention· of salt in Cheddar cheese. One part of pasteurized, separated milk (0.58% fat) was ultrafiltered (55°C, 16.0% protein), another vacuum condensed (12.5% protein) and a third was not concentrated. Cheddar cheese was manufactured using six treatments by standardizing unconcentrated milk to a casein-to-fat ratio of 0.74 with unhomogenized 35% fat cream (C); homogenized (6.9 MPa/3.5 MPa) 35% fat cream (CH); ultrafiltered milk and unhomogenized cream (UF); ultrafiltered milk and homogenized cream (UFH); condensed milk and unhomogenized cream (CM); and condensed milk and homogenized cream (CMH). Treatments C and CH had 3.7% fat and 3.5% protein and the respective values in the remaining treatments were 4.9 and 4.6. Starter (DYS, 7g/kg protein) and rennet (20 ml/100 L for C, CH or 14 ml/100 L for UF, UFH, CM, and CMH) were added. Cooking temperature (°C) was 3 7 for C and CM, 39 for CH, 36 for UF, and 38 for UFH and CMH. Salting (2. 7% by weight of milled curd) was done in three equal portions each with three minutes mixing. Salt content in the control and ultrafiltered milk cheeses was dependent on homogenization (1.33%, C; 1.83%, CH; 1.33%, UF; 1. 70%, UFH). Salt retention was higher in condensed milk cheeses than in those from ultrafiltered or unconcentrated milks and was not affected by homogenization (1.62%, CM; 1.64%, CMH). Salt recovery in cheese increased from 41.7 in C to 59.2% in CH, and from 42.5 in UF to 54.5% in UFH. The increase was smaller for condensed milk cheeses (51.5 in CM to 52.3% in CMH). For control and ultrafiltered milk cheeses the percentage salt in salt whey was lower with homogenization as was the total amount of salt whey generated. The causes for this higher retention of salt in homogenized treatments were investigated. Spraying a layer of free fat on the surface of curd from homogenized cream treatment did not significantly lower its salt retention capacity whereas salt diffusion from salted curd was slower in the homogenized treatments. The presence of a large number of small fat globules due to homogenization of cream may serve as obstruction to the flow of salt in control and ultrafiltered milk cheeses