71A-43 |
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P. J. LUCK, M. E. Carunchia Whetstine, M. A. Drake, and E. A. Foegeding. Dept. of Food Science, North Carolina State Univ., 238 Schaub Hall, Box 7624, Raleigh, NC 27695-7624 The process of making Cheddar cheese generates a natural moisture gradient within a 291 kg block. Industrially, two make styles are used: milled and stirred curd. The effects of the moisture gradient in conjunction with make style on Cheddar cheese texture are unknown. The objectives of this study are to determine the magnitude of the moisture gradient and its impact on instrumental measurements of the texture of milled and stirred curd Cheddar cheeses over one year of aging. Two sets of Cheddar cheese blocks were made at four different industrial locations in two make styles: milled and stirred. Each 291 kg block was cut 48 hr after processing into sixteen 18 kg blocks and appropriately labeled (top right, bottom left, and so forth). These blocks were then sectioned, representing the moisture gradient across the original 291 kg block and evaluated at 1, 4, 8, and 12 mo. Torsional fracture analysis and small strain creep recovery methods were used to evaluate texture. Fracture properties were unaffected by moisture gradient or make style. Age had the largest impact on fracture stress and strain. Lower fracture stress and strain at 12 mo (P < 0.0001) could be explained by continued changes, such as proteolysis, of the protein network. This is supported by a decrease in strain recoverability indicating decreased elasticity at 12 mo (P < 0.05). A moisture gradient across blocks was present up to four mo (P < 0.05). Changes in relaxation time coincided with changes in the moisture gradient, indicating a relationship between moisture and viscoelasticity (P < 0.0001). Fracture measurements indicate that aging is the predominate factor in Cheddar cheese texture. Small strain measurements show the moisture content altered viscoelasticity. Make style has no effect on instrumental texture. Controlling texture is important to consistently produce high quality Cheddar cheese.
Session 71A, Dairy Foods: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |