Executives: FYI ...

Limited enzymatic treatment of whey proteins, under the appropriate conditions, enhances the proteins' functional properties. A decrease in the gel point temperature, stronger or more elastic gels, and changes in the infrastructure of the gel network may be considered enhancements, depending on the application. Using an immobilized enzyme system can eliminate the need for a heat inactivation step. This would avoid causing any detrimental effects on the protein, such as a loss of desired functionality and the production of off-flavors and odors. Manipulating substrate concentrations and conditions to avoid potential problems associated with process scale-up is a challenge facing researchers involved in the immobilization and utilization of recombinant fusion proteins. These proteins would be used for modifying the functionality of whey protein isolate. Contact: Harold Swaisgood, North Carolina State University, Department of Food Science, Box 7624, Raleigh, NC 27695. Phone: [phone]. Fax: [phone]. Email: [e-mail].

Because warmed-over flavor continues to be one of the major quality concerns of pre-cooked meat, research continues on removing it from these products. Some scientists are using an absorbent to do the job. They found that an absorbent--polydimethylsiloxane (PDMS) solid phase microextraction (SPME) fiber--was more appropriate for extracting beef flavors than a divinylbenzene (DVB)-Carboxen-PDMS fiber. The levels of markers of warmed-over flavor, such as pentanal, hexanal, heptanal and 2,3-octanedione, significantly declined when the selected absorbent was used. Changes in flavor profile patterns could be tracked using traditional and electronic nose methodologies. Beef flavor volatiles, other than warmed-over flavor compounds, changed to a lesser extent than oxidation products.

Contact: C. Michael Greenlief, Department of Chemistry, University of Missouri, 125 Chemistry Building, Columbia, MO 65211. Phone: [phone]. Email: [e-mail].