Holzer, Z., Agric. Res. Organization, Institute of Animal Science, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Berry, B.W., Food Technol. and Safety Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705-2350, United States
Campbell, A.M., Food Technol. and Safety Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705-2350, United States
Spanier, A.M., Food Technol. and Safety Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705-2350, United States
Solomon, M.B., Food Technol. and Safety Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705-2350, United States, FTSL, ARS, USDA, BARC-East, Beltsville, MD 20705, United States

Vacuum packaged koshered (salted) meat typically undergoes a rapid color change (turning brown) with the formation of objectionable odor during refrigeration. Alterations in muscle structure have been suggested to affect the oxidative activity of salt. The hydrodynamic pressure (HDP) has been shown to physically disrupt portions of myofibrils without distorting the physical shape of the piece of meat, which may alter the effect of the kosher processing on fresh meat properties. The objective of this study was to assess the effects of the koshering process and hydrodynamic pressure (HDP), either alone or in combination, on pH, microbial growth, color and odor properties of beef. Treatments were: (1) control (C); (2) koshering process (salted = S); (3) hydrodynamic pressure treated (H); (4) the combination of koshering followed by HDP treatment (SH). The H treatment was more effective in inhibiting the normal microflora than either the S or the combination of S with H. After 14 days of storage, S samples had greater than 80% surface discoloration (brown color) compared to less than 40% discoloration on the surface for the C, H and SH samples. The H treatment reduced the surface discoloration of koshered (salted) meat samples to a level similar to that of the control. It appears that hydrodynamic pressure treatment may diminish the undesirable pro-oxidant effects (discoloration) of koshering (salting) beef.