Effect of milk pasteurization temperature and in situ whey protein denaturation on the composition, texture and heat-induced functionality of half-fat Cheddar cheese

• Published in: International dairy journal 2004-11, Vol.14 (11), p.989-1001
• Main Authors: Rynne, Nuala M., Beresford, Thomas P., Kelly, Alan.L., Guinee, Timothy P.
• Format: Article
• Language: English
• Subjects: beta-casein; Biological and medical sciences; calcium; Cheddar cheese; Composition; degradation; denaturation; firmness; Food engineering; Food industries; food quality; Functionality; Fundamental and applied biological sciences. Psychology; General aspects; Half-fat Cheddar; lipids; low fat cheeses; milk; Milk and cheese industries. Ice creams; mortality; Mycobacterium avium; nitrogen; oils; paratuberculosis; pasteurization; Pasteurization temperature; pasteurized milk; protein composition; Rheology; risk; temperature; texture; viscosity; water content; whey protein; Whey protein denaturation
• ISSN: 0958-6946; 1879-0143
• DOI: 10.1016/j.idairyj.2004.03.010

In recent years, many dairy product manufacturers pasteurize milk at temperatures higher than 72°C, so as to reduce further the risk of survival of Mycobacterium avium ssp . paratuberculosis. However, little information is available on the effect of these temperatures on cheese quality. Half-fat Cheddar cheeses (∼15%, w/w, fat) were manufactured from milk pasteurized at 72°C, 77°C, 82°C or 87°C for 26 s, and analyzed over a 360 d ripening period. The mean levels of whey protein denaturation in the pasteurized milks were 2.8%, 8.4%, 20.2% and 34.1% of total whey protein, respectively. Increasing pasteurization temperature significantly increased the levels of moisture and non-expressible serum and decreased the levels of protein, fat, calcium and free oil. Pasteurization temperature did not significantly affect the levels of pH 4.6-soluble N but influenced the degradation profiles of α s1 - and β-caseins. Increased pasteurization temperature significantly reduced fracture stress, fracture strain and firmness of cheeses. Raising the pasteurization temperature from 72°C to either 82°C or 87°C significantly reduced the flowability and stretchability of the heated cheese and increased its apparent viscosity; in contrast, increasing pasteurization from 72°C to 77°C did not affect these properties.