Dairy Industry Association of Australia

Fermentation-produced camel chymosin (CC) has been shown to produce full-fat cheddar cheese with good flavour and reduced bitterness. We investigated the use of CC on the flavour and texture of low-fat cheddar cheese. Cheeses were manufactured from skim milk (0.5% fat, casein:fat 5.1). Lactococcus lactis subsp. lactis blend that was known to produce bitterness in cheddar cheese was used as the starter culture. Calf chymosin and CC were added at levels of 7.7 and 3.9 mL/100 kg milk, respectively. Cheese functionality was assessed using the UW-Meltprofiler, texture profile analysis (TPA) and dynamic low-amplitude oscillatory rheology. A trained sensory panel evaluated the cheeses for textural and flavour attributes. There were no significant differences (p>0.05) in the composition and pH between the cheeses. TPA hardness and chewiness decreased during ripening and both parameters were significantly higher (p<0.05) in cheeses made with CC. During ripening, the maximum loss tangent (LT max) values (meltability index from rheology tests) were always significantly lower in cheeses made with CC. Temperature of LTmax was similar in all cheeses but decreased with age. Degree of flow was also lower in the cheeses made with CC compared to those made with calf chymosin. Descriptive sensory analysis indicated that the cheeses manufactured with CC had lower bitterness than those made with calf chymosin. Sensory texture analyses demonstrated that cheeses manufactured with calf chymosin were softer and less chewy than those made with CC. In low-fat cheddar cheese made with cultures prone to produce bitterness, the use of CC resulted in lower bitterness compared to cheese made with calf chymosin but CC use did not entirely eliminate bitterness.