title: Effects of exopolysaccharide-producing cultures on the viscoelastic properties of reduced-fat Cheddar cheese.
abstract: The objective was to study the influence of different exopolysaccharide (EPS)-producing and nonproducing lactic cultures on the viscoelastic properties of reduced-fat Cheddar cheese. Changes in the viscoelastic properties were followed over a ripening period of 6 mo. Results showed that the elastic, viscous, and complex moduli were higher in reduced-fat cheeses made with EPS-nonproducing cultures than in full-fat cheese. No differences in the viscoelastic properties were found between young reduced-fat cheese made with a ropy strain of Lactococcus lactis ssp. cremoris (JFR1) and its full-fat counterpart. Interestingly, the changes in viscoelastic moduli in both full-fat cheese and reduced-fat cheese made with JFR1 during ripening followed the same pattern. Whereas the moduli increased during the first month of ripening in those 2 cheeses, a dramatic decrease was observed in all other cheeses. Slopes of the viscoelastic moduli as a function of frequency were lower in the full-fat than in reduced-fat cheeses. The creep test showed that fresh reduced-fat cheese made with JFR1 was less rigid and more deformable than that made with EPS-nonproducing cultures. The creep and recovery properties of young reduced-fat cheese made with JFR1 and the full-fat type were similar. No differences were found in the viscoelastic properties between reduced-fat cheese made with no EPS and those made with EPS-producing adjunct cultures of Streptococcus thermophilus. After 6 mo of ripening, cheeses made with EPS-producing cultures maintained lower elastic and viscous moduli than did those made with no EPS.
authors.affiliation: Minnesota-South Dakota Dairy Foods Research Center, Dairy Science Department, South Dakota State University, Brookings, 57007, USA. Ashraf.Hassan@sdstate.edu
authors.forename: A N
authors.initials: AN
authors.lastname: Hassan
authors.forename: S
authors.initials: S
authors.lastname: Awad
authors.forename: K
authors.initials: K
authors.lastname: Muthukumarappan
mesh_terms: D002611:Cheese / Q000032:analysis / Q000382:microbiology*; D004548:Elasticity; D005223:Fats / Q000032:analysis*; D005511:Food Handling / Q000379:methods*; D005524:Food Technology; D013294:Lactococcus lactis / Q000378:metabolism*; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D048249:Streptococcus thermophilus / Q000378:metabolism; D013997:Time Factors; D014783:Viscosity
chemical_list: D005223:Fats; D011135:Polysaccharides, Bacterial