J. Dairy Sci. 87:3172–3182 © American Dairy Science Association, 2004. Effect of Moderate Pressure Treatments on Microstructure, Texture, and Sensory Properties of Stirred-Curd Cheddar Shreds

A moderate high-pressure processing (HPP) treat-ment is proposed to accelerate the shredability of Ched-dar cheese. High pressure processing (345 and 483MPa for 3 and 7 min) applied to unripened (1 d old) stirred-curd Cheddar cheese yielded microstructure changes that differed with pressure level and processing time. Untreated and pressure-treated cheese shredded at d 27 and 1, respectively, shared similar visual and tactile sensory properties. The moderate (345 MPa) and the higher (483 MPa) pressure treatments reduced the presence of crumbles, increased mean shred particle length, improved length uniformity, and enhanced sur-face smoothness in shreds produced from unripened cheese. High-pressure processing treatments did not affect the mechanical properties of ripened cheese or the proteolytic susceptibility of milk protein. It was concluded that a moderate HPP treatment could allow processors to shred Cheddar cheese immediately after block cooling, reducing refrigerated storage costs, with expected savings of over 15 US$/1000 lb cheese, and allowing fewer steps in the handling of cheese blocks produced for shredding. (Key words: Cheddar cheese, high-pressure pro-cessing, microstructure, shredability) Abbreviation key: HPP = high-pressure processing, NPN = nonprotein nitrogen, SEM = scanning electron microscopy, TN = total nitrogen, TPA = texture profile analysis, WSN = water-soluble nitrogen