Effects of reducing fat and salt on Cheddar cheese composition, biochemistry, texture and sensory properties, and approaches to improve the quality of reduced-fat, reduced-salt Cheddar cheese

Relatively little is known about the interactive effects of fat and salt reduction on the biochemistry, rheology and sensory properties of Cheddar cheese. The objectives of the current study were to (i) evaluate the composition, biochemical and textural properties of commercial Cheddar cheeses available in the Irish market (ii) determine the interactive effects of fat and salt reduction on Cheddar cheese composition, and age-related changes in lactose metabolism, microbiology, proteolysis, lipolysis, texture, functionality and sensory properties (iii) investigate the separate effects of reducing the calcium-to-casein ratio, and increasing casein hydrolysis (by a 2.5 fold increase in the level of added coagulant, bovine chymosin) in combination with an adjunct culture (Lactobacillus helveticus LH-32) as means of improving the quality of half-fat, half-salt Cheddar-style cheese.

A survey comprising 8 retail brands of Cheddar cheese indicated that the mean salt content for both the mild and mature cheese groups (1.83 ± 0.34 % and 1.84 ±0.17 %, respectively) was statistically similar. Based on these findings, it was decided that the salt targets for full-salt, reduced-salt and half-salt Cheddar cheeses in subsequent studies would be set at 1.9, 1.2 and 0.9% respectively. The targets for the reduced- and half-salt cheeses comply with EU Regulation (EC) No 1924/2006 for the definition for reduced-sodium foods.

Reducing fat from 33 to 22 or 16 % and salt from 1.9 to 1.2 or 0.9 % in experimental Cheddar cheese, interactively affected lactose metabolism, pH, water-to-protein ratio, concentration of free amino acids, texture and cooking properties. Fat reduction lowered the sensory acceptability of the cheese. Salt reduction had no consistent effect on the sensory characteristics. Overall, the effect of salt reduction depended on the fat content of the cheese and the parameter studied.

The texture and cooking properties of half-fat, half-salt Cheddar-style cheese were improved by reducing the calcium-to-casein ratio. Increasing the level of primary and secondary proteolysis by increasing the level of added bovine chymosin and using an adjunct-containing starter culture improved the texture, cooking properties and flavour, as determined by cheese grading, of half-fat, half-salt Cheddar-style cheese.