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stock culture was subcultured monthly on a tryptic soy agar (TSA, DIFCO, Detroit, MI) slant at 4ЊC. Working cultures were transferred from the stock culture by inoculating brain heart infusion (BHI, DIF-CO, Detroit, MI) broth. The culture was incubated at 37ЊC for 20h to obtain 10 9 colony forming units (CFU)/mL. After incubation, cells were harvested by centrifuging the culture at 5,500 ϫ g for 10 min at 4ЊC, using a JA-14 rotor (Beckman J2-HS centrifuge, Beckman Instruments, Inc., Palo Alto, CA). The cell pellet was resuspended to original volume in 0.1% peptone (DIFCO, Detroit, MI), and used to inoculate beef trimmings. The suspension was plated on MacConkey sorbitol agar (MSA, DIFCO, Detroit, MI) containing Rifampicin (100 ppm; Sigma Chemical Co., St. Louis, MO) using a Spiral Plater TM (Model 500 D, Spiral Biotech Inc., Bethesda, MD) to provide an estimate of inoculum size. Sample preparation for antimicrobial testsFresh beef trimmings ( 85% lean and 15% adipose; 4 days postmortem) were obtained from the Meat Lab of the Department of Animal Sciences and Industry, KSU. One treatment and two controls were used. E. coli O157:H7 was added to the beef trimmings to provide 10 7 CFU/g, and mixed for 4 min using a Hobart mixer (Hobart Corp., Troy, OH). LS and sterile water, treatment and control, respectively, were added to the inoculated trimmings for a final concentration of 8%, and mixed for 4 min. A second control, without LS, water or E. coli O157:H7, was mixed for 4 min and used for psychrotrophic counts. The treated sample and controls were coarsely ground (1.27 cm), followed by a fine grind (0.32 cm) using a sterile grinder (Hobart Corp., Troy, OH). Patties were made (70-90g), using a manual patty maker (Holly JR., Hollymatic Corp., Chicago, IL), packaged (Harbro Packaging Company, Chicago IL) aerobically, heat sealed (Multivac A300(16), Germany), and stored in the dark at 4ЊC for up to 3 days. The treated sample and both controls were obtained from the same batch of trimmings. Three replicates were performed for each treatment and control. Microbial analysisImmediately after inoculation, duplicate surface samples (25g) were taken each from inoculated, treated (LS or water), and noninoculated beef trimmings to check initial E. coli O157:H7 populations, antibacterial effects of treated trimmings, and psychrotrophic counts, respectively. Surface samples ( 0.7 cm deep) were taken from the prepared trimmings with a sterile scalpel and tongs. Duplicate samples (25g) also were taken from the LS treated, inoculated controls, and non-inoculated control patties at day 0, 1, 2 and 3. Samples were placed in a filtered stomacher bag (Seward, London, UK), 225 mL of 0.1% peptone water was added, and stomached for 2 min (Model 400, Tekmar, Inc., Cincinnati, OH). Serial dilutions were prepared in peptone water (0.1%) and spiral plated on MSA containing 100 ppm Rifampicin for the inoculated samples, and on plate count agar (PCA, DIFCO, Detroit, MI) for the non-inoculated controls. The plates for inoculated samples were incub...

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Characteristics were investigated on a 15%/25%, fat/added water beef frankfurter supplemented with calcium (calcium carbonate or calciumcitrate-malate complex, CCM) to meet 25, 50, 75 or 100% of adult U.S. RDA in one 45g frankfurter. Controls contained 15%/25% or 30%/10% fat/added water. Compared to controls, calcium addition did not reduce yield although batters containing CCM had lower viscosity (PCO.05). During storage. OH of calcium added frankfurters increased about 0.35 units. Frankfurters formulated with 100% levels for calcium were least acceptable to sensory panelists. Frankfurters were softer and had less springiness and chewiness (PcO.05) when supplemented with 100% levels for calcium.