Final Internal Temperature Research Articles

27 Quality Variation in Beef Chuck Eye Rolls Sourced from a Commercial Processor

Abstract The objective of this study was to evaluate quality variation in beef Chuck Eye rolls (IMPS 116D). Beef Chuck Rolls (IMPS 116A) were purchased from a commercial meat packer and fabricated to obtain beef Chuck Eye Rolls (IMPS 116D). Cases were transported to the Illinois State University Meat Lab and hand-sliced into 2.54 cm boneless beef Chuck Eye steaks (IMPS 1116D) (n = 161). Each roll contained between 7 to 10 steaks for use in further meat quality analyses in accordance with in-plant procedures. Upon slicing, steaks were allowed to bloom for 15 minutes and then used in subsequent quality analysis including color, cook loss, and tenderness evaluation. Instrumental color measurements [L* (lightness), a* (redness), b* (yellowness)] were taken for each steak in duplicate with a HunterLab Miniscan XE Plus Spectrophotometer using a D65 illuminant, 100 observer, and 35-mm aperture. All steaks were cooked to a final internal temperature of 71° C. Steaks then underwent cook loss evaluation as well as tenderness analysis via Warner-Bratzler shear force (WBSF). Statistical analysis was performed using the Proc MIXED procedure of SAS to estimate variance components of steak quality in a nested design (steak within roll within case). For all response variables, the standard error was large for the case term. Ranges of observed response values were: L* 28.03-52.15, a* 14.55-27.82, b* 12.78-25.32, cook loss 17.58-61.11, shearforce 2.10-5.86. Variance components in L* and a* values followed similar patterns in which the greatest amount of variance was contributed by steak, followed by case, followed by roll (L* 13.541 (P < 0.001) vs. 9.035 (P = 0.1790) vs. 1.958 (P = 0.1839) and a* 4.055 (P < 0.0001) vs. 1.605 ( P= 0.2124) vs. 0.632 (P = 0.1746). Case, roll, and steak contributed variance almost equally for b* though two variance components were statistically different from zero σ2case =2.133 (P = 0.2344) σ2roll = 1.627 (P = 0.0335) σ2steak = 2.37 (P < 0.0001). Case contributed approximately 1.5 times the variance in cook loss when compared with steak (σ2case = 43.687 (P = 0.1387) vs. σ2steak=29.471 (P < 0.0001)) and approximately 3.5 times more than roll ( σ2case = 43.687 vs. σ2roll = 12.077 (P = 0.0565)). The largest impact on variance in shearforce values came from steak whereas case and roll contributed almost equally (shearforce σ2case = 0.0256 (P = 0.3894)σ2roll = 0.0333 (P = 0.2040) σ2steak = 0.2454 (P < 0.0001)). Some correlations were observed: L*:a* (-0.46, P < 0.0001), L*:b* (-0.07, P = 0.3979), L*:cookloss (0.166, P = 0.0422), and cookloss:shearforce (0.274, P = 0.0007). As lower-cost alternatives to traditional center of the plate cuts continue to grow in popularity among large volume purchasers, it is important to evaluate potential differences in quality attributes. Further evaluation of the impact of case as well as steak within Chuck Eye roll on individual steak quality is warranted.

Thermophysical Properties of Beef Steaks Varying in USDA Quality Grade and Internal Temperature

The objectives of this study were to determine the influence of quality grade and internal temperature on the thermophysical properties of beef strip steaks. Beef strip loins (n=24) were collected from USDA Prime (PR), Low Choice(LC), and Standard (ST) carcasses. Strip loins were fabricated into 2.54 cm steaks at 21 d postmortem and randomly assigned to an internal temperature (4°C, 25°C, 55°C, 60°C, 71°C, 77°C). Steaks were subjected to various thermal and physical property measurements. No quality grade × internal temperature interaction was observed for diffusivity and conductivity (P > 0.05). Steaks tempered to 25°C had the greatest conductivity compared with all other internal temperature treatments (P = 0.021). A quality grade×internal temperature interaction was observed for center myosin and sarcoplasmic protein enthalpy values (P < 0.001). Raw (4°C and 25°C) ST steaks had lower enthalpy values compared with raw PR and LC steaks (P < 0.05). Raw steaks had greater surface myosin and both center and surface actin enthalpy values (P < 0.05). A quality grade × internal temperature was observed for surface and center viscoelasticity (P < 0.05). Raw steaks possessed less elastic behavior compared with cooked steaks, regardless of quality grade (P<0.05). Quality grade and internal temperature impacted expressible moisture and water holding capacity (P ≤ 0.001). ST steaks possessed increased expressible moisture and water holding capacity compared with LC and PR steaks (P<0.05). A quality grade×internal temperature was observed for Warner-Bratzler shear force and springiness (P ≤ 0.008). Internal temperature impacted all texture profile analysis attributes (P < 0.05). PR steaks were more cohesive than ST steaks (P = 0.011). These data show that final internal temperature and USDA quality grade impact thermophysical properties of beef steaks.

Development of Beef Volatile Flavor Compounds in Response to Varied Oven Temperature and Degree of Doneness

Beef volatile flavor compound (VFC) development at the center, mid, and surface layers of cooked steaks was evaluated through 18 cookery treatment combinations consisting of oven cooking temperature (OT; 177°C, 246°C, and 343°C) and final internal steak temperature (IT; 57°C, 63°C, 68°C, 74°C, 79°C, and 85°C). In total, 72 VFC were measured representing the Maillard reaction and lipid degradation. Five VFC were impacted by a three-way interaction of OT × IT × layer (P ≤ 0.030). Two VFC were impacted by a two-way interaction of OT × IT (P ≤ 0.010). Sixteen VFC were impacted by a two-way interaction of OT × layer (P ≤ 0.050). Sixteen VFC were impacted by a two-way interaction of IT × layer (P ≤ 0.050). Twenty VFC were impacted by the main effect of layer (P ≤ 0.010). Eight VFC were impacted by the main effect of IT (P ≤ 0.050). Maillard compounds were formed primarily at steak surfaces, with a general increase in content with greater final IT, and OT to a lesser extent. Lipid-derived compounds were diverse. Methyl esters and aldehydes had lower contents at steak surfaces and were primarily found within the inner portions of steaks. Conversely, certain alcohols and ketones were more prominent at steak surfaces. Development of compounds among layers was also consistently influenced by IT and OT. It may be concluded that flavor-contributing compounds vary among cooked beef steaks at different depths and cookery temperatures. As a result, OT and final IT may be utilized to mediate the final volatile compound composition.

Investigation of Smoked Beef Brisket Palatability from Three USDA Quality Grades

The objective of this study was to investigate differences in smoked beef brisket palatability from 3 USDA quality grades (USDA Prime, average [middle 1/3] Choice, and Select). Briskets (n = 54; 18 per quality grade) were seasoned with a blend of 1:1 coarse salt/black pepper, and then cooked in a smoker to a final internal temperature of 93°C for approximately 6 to 7 h. For sensory analysis, briskets were separated into point (pectoralis superficialis) and flat (pectoralis profundus) portions and then sliced perpendicular to the muscle fibers. Consumer panelists (N = 360) evaluated palatability traits, acceptability of each trait, and willingness to pay (WTP). An interaction between quality grade and muscle was observed (P ≤ 0.03) for all palatability traits, proportion of acceptable samples, and WTP. Consumers could not distinguish among quality grades of the point portions for tenderness, juiciness, flavor liking, and overall liking (P > 0.05). Point samples, regardless of quality grade, were scored greater (P < 0.05) than Prime flat samples for all palatability traits. Choice and Select flat samples were scored lesser (P < 0.05) than all other treatment combinations for tenderness, flavor liking, and overall liking. In alignment with palatability traits, consumers’ WTP was greatest for point portions, regardless of quality grade (P < 0.05), followed by Prime flat portions. Choice and Select flat portions had the lowest WTP (P < 0.05). Consumer acceptability of cooked beef brisket generally followed similar trends as palatability scores. Quality grade had no effect on the eating quality of the point portions of smoked briskets, and point portions received superior palatability scores to flat portions. Prime flat portions had greater eating quality compared to that of Choice and Select flat portions, and consumers had greater WTP for what they perceived as superior eating quality.

Physico-chemical and sensory characteristics of porkloin roast cooked to three internal temperatures

The experiment was conducted to examine the effects of three cooking internal temperatures (65. 75 or 85'C) on the physical, chemical and sensory characteristics of pork. Pork muscle, Longissimus dorsi, used were collected immediately after slaughter dnd stored overnight at -18°C. Loins were removed, allowed to thaw at room temperature, and cut into fifteen chops with an average weight of 300g. The chops were randomly allocated to three internal temperatures, 65, 75 or 85°C and transferred into the oven where they were roast cooked until the desired internal temperature was reached. The cooked weight, cooking loss, Warner Bratzler shear value and proximate composition were determined on cooked pork. Sensory attributes were also assessed by a 10-member panel using a 9-point hedonic scale. The results of the study indicated that final internal cooking Temperature had no effect (P>0.05) on cooking loss und shear value. No significant effect was observed on tenderness, juiciness and flavour. Overall acceptability was significantly p<0.05) affected with pork loin cooked to internal temperature of 85'C most acceptable. While moisture and ash contact decreased with increased. The fat content was 101 consistent influenced. The final internal cooking temperatures had no effect on the proximate composition (P>0.05) of the pork loin.

The Oft Forgotten Part of Nutrition: Lessons from an Integrated Approach to Understand Consumer Food Safety Behaviors

Abstract Objectives A multi-year, integrated methods study showed comprehensive consumer food handling practices when preparing a meal, compared to prevalence of self-reported behaviors. Experimental conditions provided insights on the effectiveness of current and future food safety messages. Methods Demographically-diverse participants were recruited from various communities in one state. Year 1: Participants prepared raw turkey burgers in a simulated home kitchen. Half of participants viewed an educational video on thermometer use before meal preparation; the other half served as a control. Year 2: Participants who self-reported washing poultry prepared raw chicken products. Half of participants received mock social media messages about not washing poultry; the other half served as a control. Food handling behaviors were coded and compared to self-reported actions and attitudes towards food safety, collected via written surveys and in-depth interviews. Results At least one contributing factor to foodborne illness was examined during each observation; cross-contamination actions were always observed. Year 1: Over 60% (n = 383) of participants self-reported owning and using a food thermometer when cooking raw meat and poultry products; however, only 35% of unprompted participants measured final internal temperature with a food thermometer. Year 2: Nearly 25% (n = 300) of participants cross-contaminated a ready-to-eat side; over 50% cross-contaminated due to poor sink sanitation. Differences between self-reported and observed food safety behaviors were seen across participant groups. Lack of sufficient handwashing leading to bacterial cross-contamination was a notable secondary outcome. Conclusions Observations more accurately reflect consumer food handling behaviors and allow for targeted message development to decrease risk of foodborne illness through safe at-home food handling. Findings and messages are shared with health educators, news and social media outlets, and directly to consumers through various resources. Funding Sources This work was funded by the U.S. Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS). All views expressed here are those of the authors and not necessarily of USDA FSIS. USDA is an equal opportunity provider, employer, and lender.

98 Final internal cooking temperature of pork chops influenced consumer eating experience more than visual color and marbling

Abstract The objective was to determine the effect of ultimate pH or “quality grade” (combination of color and marbling) on consumer eating experience of pork chops cooked to different final internal temperatures. The hypothesis was that consumers would rate a greater percentage of pork chops as acceptable with a greater pH, when graded “choice”, or when cooked to 63°C compared with 71°C or 82°C. Consumers (264 total) were served chops in 1 of 2 experiments. Experiment 1 assessed chops as high pH (6.23–5.88) or low pH (5.36–5.56) and cooked to 63°C, 71°C or 82°C. Experiment 2 classified chops as “choice” when NPPC color score ≥ 3 and marbling score was ≥ 2 or “standard” when NPPC scores were below “choice” and cooked to 63°C or 71°C. Chops were cooked with an immersion heater (ANOVA Precision Cooker, Anova Applied Electronics, San Francisco, CA) in a water bath. Consumers used a 9-point Likert-type score system where 1 was extremely tough, dry, bland, or unacceptable and 9 was extremely tender, juicy, flavorful, or acceptable. Data were organized as a percentage of responses and analyzed using the GLIMMIX procedure of SAS for both experiments with models including treatment (pH or quality grade category, temperature and all interactions). More (P < 0.01) consumers scored chops at 7, 8, or 9 for juiciness with a high pH (36.07%) compared with chops with a low pH (24.29%), but pH category did not alter other traits (P ≥ 0.13). Quality grade did not affect (P ≥ 0.30) consumer ratings of any sensory trait. In both studies, a greater (P < 0.001) percentage of consumers rated chops cooked to 63°C as acceptable compared with chops cooked to 71°C. Therefore, internal cooking temperature has a greater impact on consumer eating experience than ultimate pH or “quality grade.”

Vitamin K Content of Raw and Cooked U.S. Beef Variety Meat Items (FS14-03-19)

ObjectivesVitamin K is an essential nutrient that has been implicated in cardiovascular disease and other chronic diseases. There are two forms of vitamin K in nature. Phylloquinone (PK) is plant-based and has been well-quantified in the U.S. diet. Menaquinones (MK) are found in animal products and fermented food. However, the MK contents of food have not been well characterized. The objectives of this study were to: 1) quantify the different forms of MK (MK4 through MK13) in the beef variety meat items; and 2) determine if cooking has an effect on vitamin K content of beef variety meat items. MethodsRaw beef heart, liver, kidney, tongue, honeycomb tripe, oxtail, bone marrow, beef rocky mountain oysters (RMO), fat composite samples and blood (total samples n = 31) were obtained from processing facilities in the U.S., to provide national representation of retail-ready beef variety meat items. All raw beef samples were cooked, and final internal temperature was 80 °C. PK and the MKs in raw and cooked beef variety meat items were quantified using mass spectrometry technology. Wilcoxon Rank Signed test was used to compare PK and MK contents of raw and cooked samples. Differences were considered statistically significant at P < 0.05. ResultsThe highest concentration of any form was PK in bone marrow at 152 ± 11.9 ng/g. The fat composite samples contained between 20.9 ng/g to 63.0 ng/g of PK. Modest amounts of PK were found in liver, RMO and tripe. MKs were present in all samples analyzed with MK4, MK10, MK12 and MK13 present in the largest amount in the analyzed samples. MK4 concentrations in bone marrow and fat composite samples were 341 ± 116 and 374 ± 101 ng/g, respectively. Liver contained appreciable amounts of longer-chain MKs, primarily in the forms of MK11, MK12 and MK13, which together accounted for 95% of total vitamin K in liver. There were no significant differences in total vitamin K content between cooked and uncooked beef variety. ConclusionsTo the best of our knowledge, this is the first report of MK contents of U.S. beef variety meat items. The vitamin K content of beef items were not influenced by cooking (heating). Funding SourcesFunded by the Beef Checkoff and supported by the USDA, Agricultural Research Service under Cooperative Agreement.

Final internal cooking temperature of pork chops influenced consumer eating experience more than visual color and marbling or ultimate pH.

The objective was to determine the effect of "quality grade" (combination of visual color and marbling) or ultimate pH on consumer eating experience of pork chops cooked to different final internal temperatures. The hypothesis was that consumers would rate a greater percentage of pork chops as acceptable when graded "choice," had a greater ultimate pH, or when cooked to 63 °C compared with chops graded "standard," had a lesser ultimate pH, or when cooked to 71 or 82 °C. Consumers (264 total) were served chops in 1 of 2 experiments. Chops in Exp. 1 were classified as "choice" when NPPC visual color score ≥3 and visual marbling score was ≥2 or "standard" when NPPC scores did not meet the qualifications for "choice" and were cooked to either 63 or 71 °C. Chops in Exp. 2 were categorized as high pH (5.88 to 6.23) or low pH (5.36 to 5.56) and cooked to 63, 71, or 82 °C. Chops were cooked with a sous-vide device (ANOVA Precision Cooker, Anova Applied Electronics, San Francisco, CA) in a water bath. Consumers used a 9-point Likert-type score system where scores 1 through 3 were considered not tender, not juicy, not flavorful, or unacceptable. Scores 4 through 6 were consider neutral for tenderness, juiciness, flavor, and overall acceptability. Scores 7 through 9 were considered tender, juicy, flavorful, and acceptable. Data were organized as a percentage of responses and analyzed using the GLIMMIX procedure of SAS for both experiments with models including treatment (quality grade, ultimate pH, and final internal temperature) and all interactions. Quality grade did not affect (P ≥ 0.30) consumer ratings for any sensory trait. More (P < 0.01) consumers rated chops with a high pH (36.07%) as juicy compared with chops with a low pH (24.29%), but pH category did not alter (P ≥ 0.13) perceptions for tenderness, flavor, or overall acceptability. In both studies, a greater (P < 0.001) percentage of consumers rated chops cooked to 63 °C as acceptable compared with chops cooked to 71 °C. Therefore, internal cooking temperature has a greater impact on consumer eating experience than "quality grade" or ultimate pH.

Investigation 0f Beef Brisket Palatability from Three USDA Quality Grades

The objective of this study was to investigate differences in smoked beef brisket palatability from 3 USDA quality grades (USDA Prime, average [middle 1/3] Choice, and Select). Briskets (n = 54; 18 per quality grade) were seasoned with a blend of 1:1 coarse salt/black pepper, and then cooked in a smoker to a final internal temperature of 93°C for approximately 6 to 7 h. For sensory analysis, briskets were separated into point (pectoralis superficialis) and flat (pectoralis profundus) portions and then sliced perpendicular to the muscle fibers. Consumer panelists (N = 360) evaluated palatability traits, acceptability of each trait, and willingness to pay (WTP). An interaction between quality grade and muscle was observed (P ≤ 0.03) for all palatability traits, proportion of acceptable samples, and WTP. Consumers could not distinguish among quality grades of the point portions for tenderness, juiciness, flavor liking, and overall liking (P > 0.05). Point samples, regardless of quality grade, were scored greater (P < 0.05) than Prime flat samples for all palatability traits. Choice and Select flat samples were scored lesser (P < 0.05) than all other treatment combinations for tenderness, flavor liking, and overall liking. In alignment with palatability traits, consumers’ WTP was greatest for point portions, regardless of quality grade (P < 0.05), followed by Prime flat portions. Choice and Select flat portions had the lowest WTP (P < 0.05). Consumer acceptability of cooked beef brisket generally followed similar trends as palatability scores. Quality grade had no effect on the eating quality of the point portions of smoked briskets, and point portions received superior palatability scores to flat portions. Prime flat portions had greater eating quality compared to that of Choice and Select flat portions, and consumers had greater WTP for what they perceived as superior eating quality.

The effects of ultimate pH and color on sensory traits of pork loin chops cooked to a medium-rare degree of doneness.

The objective was to determine the effects of pH and color on sensory characteristics of boneless pork loin chops cooked to an internal endpoint temperature of 63 °C. Center cut loins (296 total) from barrows and gilts, 5 different sire lines, and a range in pH of 5.36 through 6.23 were used. Previously, ultimate pH was correlated with sensory characteristics of chops cooked to a medium (71 °C) degree of doneness. Additionally, increasing ultimate pH improved sensory tenderness and juiciness of loin chops cooked to a medium degree of doneness. However, in 2011, the United States Department of Agriculture Food Safety and Inspection Service reduced the recommended final internal cooking temperature of pork chops from 71 to 63 °C (followed by a 3-min rest). The effects of ultimate pH on sensory traits of pork chops cooked to a medium-rare (63 °C) degree of doneness are not known. Therefore, loins were categorized using historical categories based on ultimate pH: >5.95, n = 22; 5.80 to 5.95, n = 75; 5.65 to 5.80, n = 102; 5.50 to 5.65, n = 91; <5.50, n= 6. On 1-d postmortem, loins were evaluated for CIE instrumental L*, a*, b*, visual color, marbling, and subjective firmness. Then, loins were aged in vacuum packages at 4 °C until 16-d postmortem. After aging, loins were cut into 2.54-cm thick chops, vacuum-packaged, and frozen until sensory or instrumental tenderness analysis. One chop was also used to determine extractable lipid. Chops were weighed, cooked to 63 °C, cooled to approximately 23 °C, weighed again to determine cook loss, and then evaluated for Warner-Bratzler shear force. Another chop was cooked to 63 °C internal temperature and served warm to trained panelists to determine sensory traits. Coefficients of determination (R2) were calculated to determine the predictability of ultimate pH and instrumental color on sensory tenderness, juiciness, and flavor. A 1-way ANOVA and means separation test were used to determine specific differences among pH categories. Ultimate pH explained less than 5% of the variation in tenderness and less than 1% of the variation in juiciness or flavor. Furthermore, sensory tenderness did not differ (P > 0.05) among pH categories, except for chops with an ultimate pH > 5.95. Chops with a pH > 5.95 were at least 9.1% more tender (P < 0.05) than chops with a pH < 5.95. Visual and instrumental color were not predictive (R2 ≤ 0.03) of any sensory traits. Overall, pH does not influence sensory traits of pork chops cooked to medium-rare degree of doneness unless pH is at least 5.95.

Processing conditions and endpoint temperature effects on development of pink defect without pink-generating ligands in cooked ground turkey breast

This study was conducted to characterize the pink pigments associated with storing presalted (2%) and ground turkey breast trim at different processing conditions. Four treatments included: treatment (no NaCl, stored for 7 d before being cooked), treatment 2 (NaCl added and stored for 7 d before being cooked), treatment 3 (NaCl added and immediately cooked), and treatment 4 (stored for 7 d before NaCl added and cooked). All treatments were cooked to 4 endpoint temperatures (71.1, 73.9, 76.7, and 79.4°C). Processing conditions affected the pink defect in cooked ground turkey breast. Undenatured myoglobin in salted meat (treatment 2, 3, 4) still remained (17 to 19%) after cooking. Salted and stored ground turkey (treatment 2) produced a cooked product with the most reducing condition (lowest oxidation-reduction potential, ORP) and one of the most red coloration (CIE a* values). Final internal temperature had limited effects on pigment properties. ORP was similar across cooking temperatures but CIE a* values decreased with temperature. Even at 79.4°C, 15% undenatured myoglobin remained. Cooking yield decreased with temperature as expected (92.8 to 89.5%). Results indicate that to limit the degree of the pink color development processors should avoid storage of ground turkey, particularly when mixed with salt, as it favors the formation of nicotinamide-denatured globin hemochrome.

Effects of mine strata thermal behavior and mine initial temperatures on mobile refuge alternative temperature.

Federal regulations require the installation of refuge alternatives (RAs) in underground coal mines. Mobile RAs have a limited ability to dissipate heat, and heat buildup can lead to a life-threatening condition as the RA internal air temperature and relative humidity increase. The U.S. National Institute for Occupational Safety and Health (NIOSH) performed heat testing on a 10-person tent-type training RA and contracted ThermoAnalytics Inc. to develop a validated thermal simulation model of the tested RA. The model was used to examine the effects of the constant mine strata temperature assumption, initial mine air temperature, initial mine strata surface temperature (MSST), initial mine strata temperature at depth (MSTD) and mine strata thermal behavior on RA internal air temperature using 117 W (400 Btu/h) of sensible heat input per simulated miner. For the studied RA, when the mine strata temperature was treated as a constant, the final predicted RA internal air temperature was 7.1°C (12.8°F) lower than it was when the mine strata thermal behavior was included in the model. A 5.6°C (10.0°F) increase in the initial MSST resulted in a 3.9°C (7.1°F) increase in the final RA internal air temperature, whereas a 5.6°C (10°F) increase in the initial MSTD yielded a 1.4°C (2.5°F) increase in the final RA internal air temperature. The results indicate that mine strata temperature increases and mine strata initial temperatures must be accounted for in the physical testing or thermal simulations of RAs.

Relationship between Heifer Carcass Maturity and Beef Palatability

ObjectivesOur objective was to determine the relationship between carcass maturity and beef palatability of strip loin and outside round steaks.Materials and MethodsLeft sides of A (n = 30), B (n = 30), and C (n = 30) maturity heifer carcasses under 30 mo of age by dentition were used. Average skeletal maturities of the groups were A67, B49, and C48. Carcasses were selected to ensure similar marbling scores across maturity groups, and average marbling scores were Sm94, Mt02, and Mt01 for A, B, and C maturity carcasses, respectively. Beef strip loins (IMPS 180) and outside (bottom) rounds (IMPS 171B) obtained from these carcasses were purchased from AB Foods (Toppenish, WA) and transported to the University of Idaho Meat Science Laboratory. Following a 14-d aging period, wholesale cuts were removed from vacuum packaging and ischiatic heads were removed from outside rounds to produce trimmed flats. Two 2.54 cm-thick steaks were cut from the trimmed flats and anterior ends of strip loins. Steaks were used to measure Warner-Bratzler shear force (WBSF), cook loss, insoluble and total collagen, and consumer sensory attributes. Steaks used for WBSF were weighed, cooked on open hearth broilers to an internal temperature of 40°C, then turned and cooked to a final internal temperature of 71°C. Cooked steaks were re-weighed to determine cook loss and cooled to 4°C. Six cores (1.27-cm diameter) were then removed from each steak parallel with the muscle fibers and then sheared perpendicular to muscle fiber orientation using a Warner-Bratzler shear machine (GR Manufacturing, Manhattan, KS). Samples from cooked steaks were frozen at –20°C and used to determine insoluble and total collagen. Sensory panel steaks were frozen at –20°C after aging, and allowed to thaw at 4°C for 24 h prior to the consumer panel. Steaks were cooked as previously described and four 1.27-cm × 1.27-cm × steak thickness cubes were obtained from each steak. Separate sensory panels were conducted for strip loin and outside round steaks. Consumers (n = 72 panelists per panel) evaluated cooked samples for overall acceptability, tenderness, juiciness, and flavor using a 9-point scale (9 = like extremely, 1 = dislike extremely). Using an incomplete block design, panelists evaluated 5 samples from the 3 maturity groups. Data were analyzed using the Mixed Model procedure of the Statistical Analysis System (SAS Inst. Inc., Cary, NC). Significance was determined at P < 0.05 and data were considered trending at P < 0.10.ResultsHeifer carcass maturity did not significantly affect WBSF or cook loss for either outside round or strip loin steaks (P > 0.23). Likewise, insoluble and total collagen were not different for either steak type from A, B, or C maturity carcasses (P > 0.89). Strip loin steaks from C maturity carcasses tended to have higher overall acceptability (P = 0.08) and juiciness (P = 0.09) than steaks from B maturity carcasses, but steaks from B and C maturity carcasses did not differ from strip loin steaks obtained from A maturity carcasses (P > 0.11.). No differences in tenderness or flavor were observed due to maturity (P > 0.24). Similarly, maturity had no effect on sensory characteristics of outside round steaks (P > 0.30).ConclusionIn conclusion, advanced skeletal maturity does not decrease palatability of carcasses from cattle under 30 mo of age.

Evaluation of Quality Characteristics for Beef Cuts Following Different Production and Branding Approaches

ObjectivesConsumer demand has driven the expanding variety of fresh beef available for retail purchase, with considerably variable price points. The objective of this study was to assess the impact of production style and branding on the quality and sensory characteristics of ribeye steaks. Materials and MethodsThe varieties evaluated in this study were USDA Choice Black Angus, grass-fed, organic, USDA Prime, and Piedmontese. For each trial and variety, 5 steaks were cut to a target thickness of 3.18 cm from ribeye rolls procured from a local grocery store with sell-by dates within 3 d of each other. Steaks were individually overwrapped on foam trays with PVC film and stored at 1.1°C ± 2.0 under 175 ± 15 foot candle lighting for 7 d. Purge, color, cooked texture, and cook yield were measured on d 0, 1, 4, and 7 while sensory evaluation was conducted only on d 0. A Minolta colorimeter was used to measure L*a*b* values at 3 locations on the longissimus dorsi (LD) of each raw, overwrapped steak. Raw steaks were weighed and placed onto griddles preheated to 177°C, cooked to an internal temperature of 35°C, flipped over, and cooked to a final internal temperature of 70°C. For sensory analysis, eight semi-trained panelists evaluated 1.75 cm cubes of LD for aroma, juiciness, flavor, texture, and overall appearance using a nine-point hedonic scale to score, where 1 = dislike extremely and 9 = like extremely. After cooking, steaks used for texture analysis were allowed to cool for 2 h at room temperature before five cores (diameter = 1.5 cm) were taken from each steak parallel to the muscle fibers while avoiding visible exterior fat. Using a TA.XT Texture Analyzer, Warner-Bratzler shear force was measured perpendicular to the muscle fiber of each core using a rounded V-shaped blade with a 60° angle and a cross head speed of 200mm/min, where firmness equaled the maximum peak of the curve (kg) and toughness equaled the area under the curve (kg-s). This experiment was repeated three times. ResultsUSDA Prime and Piedmontese scored significantly higher (p ≤ 0.05) than all other varieties for overall acceptance with scores of 7.42 ± 1.22 and 7.04 ± 1.34, respectively. Although not always significant (p > 0.05), both USDA Prime and Piedmontese also received numerically higher ratings for all other sensory traits evaluated compared to other varieties. For d 1 objective texture measurements, USDA Prime displayed lower (p < 0.05) values for both firmness and toughness, while organic revealed the numerically highest value. At d 1 and 4 Piedmontese had significantly more purge (p < 0.05) than USDA Prime, USDA Choice Black Angus and organic, but by d 7 differences between all treatments were diminished. For any single variety, cook yields over time (ranging from 70.2 to 80.0%) were not always found consistently different than other varieties. USDA Prime had the highest a* value at d 0 (p ≤ 0.05) and was also significantly higher than organic on d 1, 4, and 7 (p < 0.05). ConclusionConsidering quality and sensory traits evaluated in this study, USDA Prime consistently stood out as being the most distinguishable branding type, while there were limited differences between Piedmontese, organic, grass-fed and USDA Choice.

Analysis of heat loss mechanisms for mobile tent-type refuge alternatives.

Federal regulations require that refuge alternatives (RAs) be located within 305 m (1,000 ft) of the working face and spaced at one-hour travel distances in the outby area in underground coal mines, in the event that miners cannot escape during a disaster. The Mine Safety and Health Administration mandates that RAs provide safe shelter and livable conditions for a minimum of 96 hours while maintaining the apparent temperature below 35 °C (95 °F). The U.S. National Institute for Occupational Safety and Health used a validated thermal simulation model to examine the mechanisms of heat loss from an RA to the ambient mine and the effect of mine strata composition on the final internal dry bulb temperature (DBT) for a mobile tent-type RA. The results of these studies show that 51 percent of the heat loss from the RA to the ambient mine is due to radiation and 31 percent to conduction. Three mine width and height configurations and four mine strata compositions were examined. The final DBT inside the RA after 96 hours varied by less than 1 °C (1.8 °F) for the three mine width/height configurations and by less than 2 °C (3.6 °F) for the four mine strata compositions.

Effect of Product Dimensions and Surface Browning Method on Salmonella Contamination in Frozen, Surface-Browned, Breaded Chicken Products Treated with Antimicrobials.

Not-ready-to-eat breaded chicken products formulated with antimicrobial ingredients were tested for the effect of sample dimensions, surface browning method and final internal sample temperature on inoculated Salmonella populations. Fresh chicken breast meat portions (5 × 5 × 5 cm), inoculated with Salmonella (7-strain mixture; 5 log CFU/g), were mixed with (5% v/w total moisture enhancement) (i) distilled water (control), (ii) caprylic acid (CAA; 0.0625%) and carvacrol (CAR; 0.075%), (iii) CAA (0.25%) and ε-polylysine (POL; 0.5%), (iv) CAR (0.15%) and POL (0.5%), or (v) CAA (0.0625%), CAR (0.075%) and POL (0.5%). Sodium chloride (1.2%) and sodium tripolyphosphate (0.3%) were added to all treatments. The mixtures were then ground and formed into 9 × 5 × 3 cm (150 g) or 9 × 2.5 × 2 cm (50 g) portions. The products were breaded, browned in (i) an oven (208 °C, 15 min) or (ii) deep fryer (190 °C, 15 s), packaged, and stored at -20 °C (8 d). Overall, maximum internal temperatures of 62.4 ± 4.0 °C (9 × 2.5 × 2 cm) and 46.0 ± 3.0 °C (9 × 5 × 3 cm) were reached in oven-browned samples, and 35.0 ± 1.1 °C (9 × 2.5 × 2 cm) and 31.7 ± 2.6 °C (9 × 5 × 3 cm) in fryer-browned samples. Irrespective of formulation treatment, total (after frozen storage) reductions of Salmonella were greater (P < 0.05) for 9 × 2.5 × 2 cm oven-browned samples (3.8 to at least 4.6 log CFU/g) than for 9 × 5 × 3 cm oven-browned samples (0.7 to 2.5 log CFU/g). Product dimensions did not (P ≥ 0.05) affect Salmonella reductions (0.6 to 2.8 log CFU/g) in fryer-browned samples. All antimicrobial treatments reduced Salmonella to undetectable levels (<0.3 log CFU/g) in oven-browned 9 × 2.5 × 2 cm samples. Overall, the data may be useful for the selection of antimicrobials, product dimensions, and surface browning methods for reducing Salmonella contamination.

Thermal Inactivation of Shiga Toxin–Producing Escherichia coli Cells within Cubed Beef Steaks following Cooking on a Griddle

Thermal inactivation of Shiga toxin-producing Escherichia coli (STEC) cells within knitted/cubed beef steaks following cooking on a nonstick griddle was quantified. Both faces of each beef cutlet (ca. 64 g; ca. 8.5 cm length by 10.5 cm width by 0.75 cm height) were surface inoculated (ca. 6.6 log CFU/g) with 250 μl of a rifampin-resistant cocktail composed of single strains from each of eight target serogroups of STEC: O26:H11, O45:H2, O103:H2, O104:H4, O111:H(2), O121:H19, O145:NM, and O157:H7. Next, inoculated steaks were (i) passed once through a mechanical tenderizer and then passed one additional time through the tenderizer perpendicular to the orientation of the first pass (single cubed steak; SCS) or (ii) passed once through a mechanical tenderizer, and then two tenderized cutlets were knitted together by passage concomitantly through the tenderizer two additional times perpendicular to the orientation of the previous pass (double cubed steak; DCS). SCS and DCS were individually cooked for up to 3.5 min per side in 30 ml of extra virgin olive oil heated to 191.5°C (376.7°F) on a hard-anodized aluminum nonstick griddle using a flat-surface electric ceramic hot plate. Regardless of steak preparation (i.e., single versus double cubed steaks), as expected, the longer the cooking time, the higher the final internal temperature, and the greater the inactivation of STEC cells within cubed steaks. The average final internal temperatures of SCS cooked for up 2.5 min and DCS cooked for up to 3.5 min ranged from 59.8 to 94.7°C and 40.3 to 82.2°C, respectively. Cooking SCS and DCS on an aluminum griddle set at ca. 191.5°C for 0.5 to 2.5 min and 1.0 to 3.5 min per side, respectively, resulted in total reductions in pathogen levels of ca. 1.0 to ≥6.8 log CFU/g. These data validated that cooking SCS (ca. 0.6 cm thick) or DCS (ca. 1.3 cm thick) on a nonstick aluminum griddle heated at 191.5°C for at least 1.25 and 3.0 min per side, respectively, was sufficient to achieve a 5.0log reduction in the levels of the single strains from each of the eight target STEC serogroups tested.

Determination of advanced glycation endproducts in cooked meat products

Advanced glycation endproducts (AGEs), a pathogenic factor implicated in diabetes and other chronic diseases, are produced in cooked meat products. The objective of this study was to determine the AGE content, as measured by Nε-carboxymethyllysine (CML) levels, in cooked chicken, pork, beef and fish (salmon and tilapia) prepared by three common cooking methods used by U.S. consumers: frying, baking, and broiling. The CML was detected in all the cooked samples, but the levels were dependent on types of meat, cooking conditions, and the final internal temperature. Broiling and frying at higher cooking temperature produced higher levels of CML, and broiled beef contained the highest CML content (21.8μg/g). Baked salmon (8.6μg/g) and baked tilapia (9.7μg/g) contained less CML as compared to the other muscle food samples.

Thermal Inactivation of Escherichia coli O157:H7 and Non-O157 Shiga Toxin-Producing Escherichia coli Cells in Mechanically Tenderized Veal

Preflattened veal cutlets (ca. 71.5 g, ca. 0.32 cm thick) were surface inoculated with ca. 6.8 log CFU/g of a multistrain cocktail of Escherichia coli O157:H7 (ECOH) or a cocktail made of single strains of serogroups O26, O45, O103, O104, O111, O121, and O145 of Shiga toxin-producing E. coli (STEC) cells and then were mechanically tenderized by passing once through a “Sir Steak” tenderizer. For each cooking time, in each of at least three trials, three inoculated and tenderized cutlets, with and without breading, were individually cooked in 15 or 30 ml of canola oil for 0.0, 0.75, 1.0, 1.25, 1.5, 1.75, or 2.25 min per side on an electric skillet set at 191.5°C. The temperatures of the meat and of the skillet were monitored and recorded using a type J thermocouple. Regardless of the breading or volume of oil used to cook the meat, the longer the cooking times, the higher was the internal temperature of the meat, along with a greater reduction of both ECOH and STEC. The average final internal temperature of the meat at the approximate geometric center ranged from 56.8 to 93.1°C. Microbial reductions of ca. 2.0 to 6.7 log CFU/g and ca. 2.6 to 6.2 log CFU/g were achieved for ECOH and STEC, respectively. Our data also revealed no differences in thermal inactivation of ECOH relative to the volume of oil used to cook nonbreaded cutlets. However, when cooking breaded cutlets, the use of more (30 ml) compared with less (15 ml) cooking oil resulted in greater reductions in pathogen numbers. To deliver about a 5.0-log reduction of ECOH and STEC, and to achieve the recommended internal temperature of 71.1°C, it was necessary to cook mechanically tenderized veal cutlets for at least 1.5 min per side on a preheated electric skillet set at 191.5°C and containing 15 ml of cooking oil. These data also established that cooking times and temperatures effective for inactivating serotype O157:H7 strains of E. coli in tenderized veal are equally effective against the additional six non-O157 Shiga toxin-producing strains investigated herein.