Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 2004
Publication Date: August 15, 2004
Citation: Van Hekken, D.L., Tunick, M.H., Park, Y.W. 2004. Effect of frozen storage on the proteolytic and rheological properties of Monterey Jack caprine milk cheese. Institute of Food Technology Annual Meeting. Paper 17A-17. Technical Abstract: There is a demand for consistent and year-round supply of caprine milk products but the dairy goat industry is challenged by seasonal milk production. The impact of freezing and extended frozen storage on the rheological and proteolytic properties of semi-hard Monterey Jack caprine milk cheese was evaluated to determine the potential for extending its marketability. Milk from the Fort Valley State University's dairy goat herd was used to manufacture Monterey Jack cheese. Cheeses were aged at 4C for 6 weeks prior to 4 storage treatments: unfrozen fresh control, UFC; frozen-thawed control, FTC, stored at -20C for 2 days; and 3MF and 6MF, stored at -20C for 3 and 6 months. Protein profiles were generated using SDS-PAGE and rheological properties were obtained using texture profile, torsion, and small amplitude oscillatory shear analyses. Very little proteolysis occurred in Monterey Jack cheese during frozen storage, while changes did occur in the rheological properties. The UFC and FTC cheeses had similar viscoelastic properties while long term frozen storage resulted in higher elastic and viscous moduli in the 3MF and 6MF cheeses. As the length of frozen storage increased, the shear stress and strain at the point of fracture for the cheeses decreased. This suggested that the formation of the ice crystals, not proteolysis, altered the macrostructure of the cheese matrix. Although other quality factors also must be considered, the freezing of Monterey Jack caprine milk cheese may not be highly desirable because of the decrease in the textural quality of the cheese.