The effects of ozone, chlorine dioxide, cetylpyridinium chloride and trisodium phosphate as multiple antimicrobial interventions on microbiological, instrumental color, and sensory color and odor characteristics of ground beef.

The impact of multiple antimicrobial interventions on ground beef microbial, color and sensory characteristics was studied. For this, beef trimmings were inoculated with Escherichia coli (EC) and Salmonella typhimurium (ST) then treated with either (1) 1% ozonated water followed by 5% acetic acid (OA), (2) 1% ozonated water followed by 0.5% cetylpyridinium chloride (OC), (3) 200 ppm chlorine dioxide followed by 10% trisodium phosphate (CT) or (4) control (C). Trimmings were ground, packaged and sampled at 0, 1, 2, 3 and 7 days of display for EC, ST, coliforms (CO), aerobic plate count (APC), instrumental color and sensory color and odor characteristics. The OA and OC treatments reduced (P<0.05) all bacterial types evaluated, while CT reduced (P<0.05) EC, CO and APC. The CT treatment was redder (P<0.05) in overall color than C, and there was no difference (P>0.05) in beef odor or off odor between OC, CT or C treatments.

Reduction of microorganisms in ground beef using multiple intervention technology.

The effectiveness of multiple antimicrobial interventions on ground beef microbial, instrumental color and sensory characteristics through display was studied. Beef trimmings were inoculated with Escherichia coli (EC) and Salmonella typhimurium (ST) then treated with either: (1) 5% acetic acid followed by 0.5% cetylpyridinium chloride (AC); (2) 200 ppm chlorine dioxide followed by 0.5% cetylpyridinium chloride (CC); (3) 0.5% cetylpyridinium chloride followed by 10% trisodium phosphate (CT); or (4) control (C). Trimmings were ground, packaged and sampled through display for EC, ST, coliforms (CO), aerobic plate count (APC), and sensory color and odor characteristics. All treatments reduced (P<0.05) all bacterial types monitored through display. Ground beef from the CC treatment was similar (P>0.05) in redness (a*) to C. The CT treatment remained (P<0.05) redder (a*) in color, contained more (P<0.05) oxymyoglobin and had less (P<0.05) overall, worst point and percentage discoloration than C by day 7 of display.

The effects of acetic acid, gluconic acid and trisodium citrate treatment of beef trimmings on microbial, color and odor characteristics of ground beef through simulated retail display.

Antimicrobial effects of selected acidulants in a ground beef production system were studied. Lean beef trimmings were inoculated with Escherichia coli (EC) and Salmonella Typhimurium (ST) then treated with either 5% acetic acid, 5% gluconic acid (GA) or 5% trisodium citrate and then compared with an untreated control (C). Trimmings were ground, packaged and sampled at 0, 1, 2, 3 and 7 days of display for EC, ST, coliforms, aerobic plate counts (APC), sensory color and odor as well as instrumental color traits. Acetic acid reduced (P<0.05) all bacterial types evaluated, but caused changes (P<0.05) in ground beef color (L*, a* and b* values) and odor characteristics. Conversely, although GA reduced (P<0.05) EC and APC, it had little effect on color or odor characteristics as compared with C. Trisodium citrate did not affect (P>0.05) microbial populations, color or odor characteristics of ground beef.

Microbial, instrumental color and sensory color and odor characteristics of ground beef produced from beef trimmings treated with ozone or chlorine dioxide.

The effects of beef trimming decontamination with ozone and chlorine dioxide on ground beef microbial, color and odor characteristics were studied. Beef trimmings were inoculated with Escherichia coli (EC) and Salmonella Typhimurium (ST), then treated with either 1% ozonated water for 7 min (7O) or 15 min (15O), or with 200 ppm chlorine dioxide (CLO) and compared with a control (C). Trimmings were ground, packaged and sampled at 0, 1, 2, 3 and 7 days of display for EC, ST, coliforms (CO), aerobic plate counts (APC), instrumental color, as well as sensory color and odor characteristics. The 15O and CLO treatments reduced (P<0.05) all bacterial types evaluated, whereas the 7O treatment reduced (P<0.05) APC and ST. All treatments caused ground beef to become lighter (L*) in color (P<0.05); however, the 15O treatment was similar (P>0.05) in redness (a*), percentage discoloration, beef odor and off odor intensities when compared to C.

Effects of hot water and lactic acid treatment of beef trimmings prior to grinding on microbial, instrumental color and sensory properties of ground beef during display.

The impact of 82°C hot water (HW) or 5% lactic acid (LA) applied aerobically or by vacuum to beef trimmings prior to grinding on Salmonella Typhimurium (ATCC 1769NR; ST), Escherichia coli (ATCC 11775; EC), coliform (CO), aerobic plate count (APC), instrumental color and sensory characteristics of ground beef through simulated retail display was investigated. For this, beef trimmings were inoculated with a mixture (7 log CFU/ml each) of ST and EC, and treated either aerobically or under vacuum in a tumbler with HW or LA antimicrobials. Trimmings were ground, packaged and sampled on days 0, 1, 2, 3 and 7 of display for ST, EC, CO, APC, sensory and instrumental color characteristics. Vacuum HW or LA application had no additive effect (P>0.05) when compared with aerobic application for reducing EC, ST, CO or APC. However, lactic acid was effective for reducing (P<0.05) EC, CO and APC, but reduced ground beef redness.

Reduction of E. coli, Salmonella typhimurium, coliforms, aerobic bacteria, and improvement of ground beef color using trisodium phosphate or cetylpyridinium chloride before grinding.

The impact of 10% trisodium phosphate (TSP) or 0.5% cetylpyridinium chloride (CPC) applied to beef trimmings either aerobically or under vacuum before grinding on Salmonella typhimurium (ST), Escherichia coli (EC), coliform (CO), aerobic plate count (APC), color and sensory attributes of ground beef through display was studied. For this, beef trimmings were inoculated with ST and EC then treated with either TSP or CPC in vacuum or aerobic conditions. Trimmings were ground, packaged, displayed under simulated retail conditions and sampled on days 0, 1, 2, 3 and 7 for microbial, instrumental color, and sensory color and odor characteristics. Aerobic and vacuum antimicrobial application methods were equally effective (P>0.05) for reducing microorganisms in ground beef. Trisodium phosphate and CPC reduced (P<0.05) all bacterial types monitored. In addition, TSP and CPC improved (P>0.05) ground beef redness (a*), oxymyoglobin stability (630 nm/580 nm) and sensory overall color throughout display without adversely affecting odor characteristics.

Impact of heating-degree-day accumulation during bermudagrass hay storage on nutrient utilization by lambs.

Spontaneous heating in stored alfalfa (Medicago sativa) has reduced forage quality and DM and N digestibility through microbial respiration and Maillard polymer formation. The impact of heating-degree-day (HDD) accumulation in stored bermudagrass (Cynodon dactylon [L.] Pers.) was evaluated for its effect on nutrient utilization by lambs. Twenty Rambouillet wether lambs (53.1 +/- 0.74 kg) were used in a completely randomized total collection experiment. The hays selected for this study had previously undergone spontaneous heating, producing either 5, 119, 201, 273, or 401 HDD (> 35 degrees C) during a 60-d storage period. Lambs were offered diets of these hays at 1.5% of BW. Dry matter intake did not differ (P = 0.59) among hays. Linear relationships were detected between HDD and apparent digestibilities of DM (y = 59.1 - 0.016x; P < 0.01; R2 = 0.37), OM (y = 59.3 - 0.017x; P < 0.01; R2 = 0.43), NDF (y = 66.4 - 0.012x; P = 0.01; R2 = 0.30), and hemicellulose (y = 74.0 - 0.012x; P = 0.02; R2 = 0.27). Similarly, significant regressions were observed for fecal N excretion (g/d; y = 4.70 + 0.004x; P < 0.01; R2 = 0.68), apparent N absorbed (g/d; y = 7.4 - 0.005x; P < 0.01; R2 = 0.50), apparent N absorption (%; y = 61.2 - 0.038x; P < 0.01; R2 = 0.71), apparent neutral detergent insoluble nitrogen digestibility (%; y = 85.8 - 0.026x; P = 0.01; R2 = 0.73), and apparent acid detergent insoluble nitrogen digestibility (%; y = 1.5 + 0.101x; P < 0.01; R2 = 0.62). Therefore, spontaneous heating during the storage of bermudagrass hay has a negative effect on dry matter and fiber digestion and nitrogen absorption by lambs.

Effects of dietary magnesium and duration of refrigerated storage on the quality of vacuum-packaged, boneless pork loins.

Quality data were initially collected on 78 pork loins from crossbred pigs fed diets containing 0, 1.25 or 2.5% magnesium mica (MM). Loins were then vacuum-packaged, and randomly assigned to either 4 or 8 weeks of storage at 2°C. Dietary MM had no (P > 0.05) effect on moisture loss/retention or subjective and objective color measurements. Purge volume increased (P<0.05) and drip loss decreased (P<0.05) as storage time increased. Moreover, longissimus thoracis et lumborum (LM) chops became lighter (P<0.05), redder (P<0.05), and more yellow (P<0.05) during 8 weeks of storage. Although TBARS values increased linearly (P<0.001) during extended storage, LM chops from pigs fed 2.5% MM tended to have lower (P<0.07) TBARS values after 4 weeks of storage than chops from pigs fed 0 and 1.25% MM. After 8 weeks of storage, however, there was a tendency for TBARS values of chops from pigs fed 1.25% MM to be lower (P<0.07) than chops from pigs fed 2.5% MM. Even though feeding swine diets containing MM did not affect color and water-holding capacity of pork loins during storage, the data indicated inclusion of MM in swine diets may retard onset of oxidative rancidity in vacuum-packaged pork loins.