Progress 10/01/04 to 09/30/09
Outputs
OUTPUTS: Trials were conducted to determine the effect of pH enhancement (PHE) on meat quality. Muscles designated for PHE were injected with a solution of water, ammonium hydroxide, and salt. A 2 x 2 x 2 factorial design was used with two beef sources: Limousin cattle (LIMO) and Certified Angus Beef (CAB), two muscles: longissimus (LL) and semitendinosus (ST), and two treatments: control (CON) and PHE. Meat pH was raised from 5.39 for CON to 6.16 for PHE (P<0.05). pH enhancement had greater effects on LIMO (CON vs. PHE=5.56 vs. 7.27 for Overall Like, 5.61 vs. 7.90 for Like of Tenderness, 5.41 vs. 7.43 for Like of Juiciness) than on CAB (CON vs. PHE=5.83 vs. 7.19 for Overall Like, 5.62 vs. 7.27 for Like of Tenderness, 5.62 vs. 7.07 for Like of Juiciness). Beef steaks from a Total Quality Management (TQM) system developed to produce steaks with exceptional palatability were tested against other steaks including average U.S. beef (AVG), USDA Prime beef (PRIME), salt/phosphate-enhanced beef (SPE), and pH-enhanced beef (PHE). For LL steaks, Overall Like ratings were 7.48 for PHE, 7.31 for TQM, 7.25 for PRIME, 6.98 for SPE, and 6.85 for AVG (diff>0.35, P<0.05). For ST steaks, Overall Like ratings were 6.19 for PHE, 5.98 for TQM, 5.72 for SPE, 5.43 for AVG, and 5.08 for PRIME (diff>0.34, P<0.05). A trial determined the effectiveness of PHE on hams processed from pale (PL), average (AV) and dark (DK) colored muscles. Consumer ratings for appearance of CON vs. PHE, respectively, was 6.0 vs. 6.7 for Overall Like, 5.9 vs. 6.8 for Like of Color and 6.0 vs. 5.6 for Like of Texture (P<0.05). When tasting, consumers rated Like of Juiciness higher for PHE than CON (6.7 vs. 6.2), but Overall Like and Like of Flavor was increased by PHE only when using PL muscles (P<0.05). A trial determined the effect of PHE on consumer acceptability of roast beef (RB), grilled chicken breast (CK), grilled pork loin (PK), beef prime rib (PR), beef pot roast (PT), and barbeque beef brisket (BR). Consumer mean ratings for Overall Like were higher for PHE than CON for RB (6.90 vs. 6.49), CK (6.83 vs. 6.19), PK (7.13 vs. 5.33), PR (8.36 vs. 7.90), PT (8.15 vs. 7.76), and BR (7.50 vs. 6.92) (P<0.05). Normal (NN) and callipyge (CN) lamb was used to determine the mechanism by which palatability was improved with PHE. The PHE LL had higher cooked moisture retention (72.6 vs. 65.9 %) than CON (P<0.05); PHE increased desmin degradation for NN (90.1 vs. 94.3 %), but decreased desmin degradation for CN (40.8 vs. 34.6 %, P<0.05); sarcomere length was not affected by PHE. A three-phase study was conducted to determine the usefulness of electrical impedance to predict beef tenderness. Impedance measurements on the exposed LL using 5 cm penetration depth were more accurate at predicting WBS than measurements at other anatomical locations or using other electrode designs. Near-infrared, impedance, and BeefCam explained seven, five and three percent of the variation in WBS, respectively. Phase angle of LL decreased slightly from d 1 to d 7 postmortem and was lower for Bos taurus than Bos indicus (P<0.05), indicating phase angle may be inversely related to extent of postmortem proteolysis. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
We have shown that pH enhancement of beef dramatically improves the palatability of cooked steaks. The improvements have been the greatest on leaner types of beef. We have shown that pH enhancement makes lean beef have higher consumer palatability ratings than non-enhanced fatter beef. We have shown that pH-enhancement had little to no effect on sarcomere length and desmin degradation, but improved palatability of normal and callipyge lamb, by increasing cooked moisture retention, improving consumer acceptability of callipyge lamb to near-normal levels. We have shown that electrical impedance has potential to rapidly predict beef tenderness, possible because of a relationship with postmortem proteolysis. The ability to predict tenderness would allow industry the ability to sort carcasses into desired product types and improve overall meat quality. Improving meat quality would benefit both consumers and livestock producers. Because leaner animals produce meat which is more variable in quality, improvements in meat quality will enable consumers to enjoy tenderness and flavor along with enhanced nutrition and health. Livestock producers will benefit because improvements in meat quality will increase the demand for meat products.
Publications
- No publications reported this period
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: A three-phase study was conducted to determine the usefulness of electrical impedance to predict beef tenderness. A prototype instrument utilized four electrodes in a linear arrangement (outside two electrodes = electrical source; middle two electrodes = detection) to measure reactance, resistance, and phase angle. Phase I was performed in a commercial packing plant in Greeley, Colorado to determine optimal electrode arrangement and anatomical measurement location and to determine if electrical impedance had potential to predict beef tenderness. Electrical impedance was measured on the exposed longissimus muscle of 300 randomly-chosen beef carcasses to define population variation. Ninety-three additional carcasses were then selected to equally represent all population quantiles of electrical impedance, and impedance was measured on these carcasses at various anatomical locations, using various electrode arrangements and electrode depths. Carcass data were collected and a section of longissimus used for Warner-Bratzler shear force (WBS) determination on d 5 and d 14. Data from phase I showed that electrical impedance measurements on the exposed longissimus using 5 cm penetration depth were more accurate at predicting WBS than measurements at other anatomical locations or using other electrode designs. In addition, electrical impedance had potential to predict beef tenderness and was additive to muscle color and carcass traits at explaining variation in WBS. Phase II was performed in a commercial packing plant in Cactus, Texas to compare electrical impedance to existing technology (BeefCam and NIR) to predict beef tenderness. Electrical impedance was measured on the exposed longissimus muscle of 300 randomly-chosen beef carcasses to define population variation. Three hundred additional carcasses were selected to equally represent all population quantiles of electrical impedance. Carcass data were collected and a section of longissimus was used for WBS determination on d 14. Data from Phase II showed that NIR, impedance, and BeefCam explained seven, five and three percent of the variation in WBS, respectively. When used together, NIR and impedance explained 12% of the WBS variation. Impedance was the most effective technology at sorting out the very tender (<3.0 kg WBS) carcasses, whereas NIR was the most effective technology at sorting out the tough (>5.0 kg WBS) carcasses. Phase III utilized 28 beef carcass sides to determine the effect of breed type (Bos taurus vs. Bos indicus), suspension method (traditional vs. hip), and aging electrical impedance measurements. Steaks were used for WBS determination on d 1 and d 10 postmortem. Data from Phase III showed longissimus WBS was lower for Bos taurus than Bos indicus, lower for hip suspension than traditional suspension, and lower for d 10 than d 1 (P < 0.05). Phase angle of the longissimus decreased slightly from d 1 to d 7 postmortem and was lower for Bos taurus than Bos indicus (P < 0.05), indicating that phase angle may be inversely related to extent of postmortem proteolysis. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
We have shown that electrical impedance has potential to rapidly predict beef tenderness, possible because of a relationship with postmortem proteolysis. The ability to predict tenderness would allow industry the ability to sort carcasses into desired product types and improve overall meat quality. Improving meat quality would benefit both consumers and livestock producers. Because leaner animals produce meat which is more variable in quality, improvements in meat quality will enable consumers to enjoy tenderness and flavor along with enhanced nutrition and health. Livestock producers will benefit because improvements in meat quality will increase the demand for meat products.
Publications
- Machado, T. J., D. M. Wulf, R. H. Pritchard, and K.W. Bruns. 2008. Timed protein restrictions in feedlot diets to alter adipose deposition with the goal to increase marbling in beef carcasses. Proc. Recip. Meat Conf., Gainesville, FL.
- Nath, T. M., C. D. Nath, T. M. Machado, A. D. Weaver, and D. M. Wulf. 2008. The use of electrical impedance to rapidly predict beef tenderness. Proc. Recip. Meat Conf., Gainesville, FL.
- Widmer, M. R., L. M. McGinnis, D. M. Wulf, and H. H. Stein. 2008. Effects of feeding distillers dried grains with solubles, high-protein distillers dried grains, and corn germ to growing-finishing pigs on pig performance, carcass quality, and the palatability of pork. J Anim Sci 86:1819-1831.
- Muench, L. K., R.J. Maddock, and D.M. Wulf. 2008. Effects of potential antimicrobial ingredients used to control Listeria monocytogenes on quality of natural casing frankfurters. Meat Sci 80:805-813.
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Progress 01/01/07 to 12/31/07
Outputs
A trial was conducted to determine if pH-enhancement improved palatability of normal (NN) and callipyge (CN) lamb and to determine the mechanism by which palatability was improved. Ten ewe and 10 wether lambs of each genotype were harvested and carcass characteristics measured. Longissimus (LM) was removed at 2 d postmortem. Alternating sides served as either control (CON) or pH-enhanced (PHE). Designated PHE LM were injected to a target 120% by weight with a solution containing water, ammonium hydroxide, carbon oxide and salt. Muscle pH, cooking loss, Warner-Bratzler shear force (WBS), sarcomere length, cooked moisture retention, and desmin degradation were evaluated for LM chops. Trained sensory panel rated LM juiciness, tenderness, and lamb flavor on 8-pt scales and off-flavors on 4-pt scales, while take home consumer panelists evaluated LM chops for raw and eating characteristics on 7-pt scales. The CN lambs had heavier live and hot carcass weights, less adjusted
fat thickness, lower yield grades, and higher conformation scores than NN (P < 0.05). The NN LM had shorter sarcomeres (1.37 vs. 1.45 um), lower WBS values (2.65 vs. 6.95 kg), higher juiciness ratings (5.60 vs. 4.98), more off-flavors (3.62 vs. 3.73), lower consumer ratings for raw characteristics [like of portion size (4.21 vs. 5.25), like of color (5.09 vs. 5.33), like of leanness (4.42 vs. 5.23), overall like of appearance (4.62 vs. 5.37)] and higher consumer ratings for eating characteristics [like of juiciness (5.76 vs. 4.73), like of flavor (5.61 vs. 4.89)] than CN (P < 0.05). The PHE LM had higher cooked moisture retention (72.62 vs. 65.90 %), lower WBS values (3.38 vs. 6.23 kg), higher juiciness ratings (5.43 vs. 5.15), less off-flavors (3.63 vs. 3.71), and higher consumer ratings for raw characteristics [like of portion size (5.04 vs. 4.41), like of color (5.54 vs. 4.88), overall like of appearance (5.15 vs. 4.84)] and eating characteristics [like of juiciness (5.61 vs.
4.88), like of flavor (5.43 vs. 5.07)] than CON (P < 0.05). Significant genotype by treatment interactions occurred for muscle pH, desmin degradation, tenderness, lamb flavor intensity, consumer like of texture/tenderness, and consumer overall like of eating quality (P < 0.05). The PHE LM had increased muscle pH, more for NN (5.94 vs. 6.92) than CN (5.89 vs. 6.35, P < 0.01). pH-enhancement increased desmin degradation for NN (90.10 vs. 94.26 %), but decreased desmin degradation for CN (40.83 vs. 34.56 %, P < 0.01). pH-enhancement improved tenderness ratings for CN (4.24 vs. 5.74) more than for NN (5.96 vs. 7.04, P < 0.05). For lamb flavor intensity, PHE decreased ratings for NN (5.18 vs. 4.42, P < 0.01), but had no effect for CN (4.74 vs. 4.74). For consumer like of texture/tenderness, PHE improved ratings for CN (3.68 vs. 5.06) more than for NN (5.49 vs. 6.17, P < 0.01). For consumer overall like of eating quality, PHE improved ratings for CN (4.03 vs. 5.03) more than for NN (5.46
vs. 5.87, P < 0.05).
Impacts
We have shown that pH-enhancement had little to no effect on sarcomere length and desmin degradation, but improved palatability of normal and callipyge lamb, by increasing cooked moisture retention, improving consumer acceptability of callipyge lamb to near-normal levels. Improving meat quality would benefit both consumers and livestock producers. Because leaner animals produce meat which is more variable in quality, improvements in meat quality will enable consumers to enjoy tenderness and flavor along with enhanced nutrition and health. Livestock producers will benefit because improvements in meat quality will increase the demand for meat products.
Publications
- Nath, T. M., D. M. Wulf, and P. Lu. 2007. Effect of portion size/shape on trained sensory panel effectiveness at determining meat palatability. Proc. Recip. Meat Conf., Brookings, SD.
- Nath, C. D., T. M. Nath, and D. M. Wulf. 2007. Effects of animal age, boning method (hot-boned vs. cold-boned), and pH-enhancement on consumer ratings of beef. Proc. Recip. Meat Conf., Brookings, SD.
- Everts, A. K. R., D. M. Wulf, T. L. Wheeler, A. J. Everts, and J. A. Daniel. 2007. Effects of pH-enhancement on sarcomere length, desmin degradation, moisture retention, palatability and consumer acceptability of normal and callipyge lamb. Proc. Recip. Meat Conf., Brookings, SD.
- Machado, T. J., and D. M. Wulf. 2007. Comparing three types of beef feedlot facilities and their effect on meat quality. Proc. Recip. Meat Conf., Brookings, SD.
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Progress 01/01/06 to 12/31/06
Outputs
A trial determined the effectiveness of pH-enhancement with ammonium hydroxide on hams processed from pale, average and dark colored muscles. Inside hams (n = 100) were procured representing the palest (PL: L* < 48.0), average (AV: L* = 52.0 to 52.9) and darkest (DK: L* > 57.0) ten percent relative to the distribution observed in a commercial packing plant. One-half of the muscles served as controls (CON) and were conventionally processed, while others were pH enhanced (PHE) using patented technology from Freezing Machines, Inc. Muscles were injected to have a final product concentration of 2.6% salt, 0.6% sucrose, 0.35% phosphate (CON only), 0.055% sodium erythorbate, ammonium hydroxide (PHE only), carbon oxide (PHE only), and 200 ppm sodium nitrite. Muscles were chunked, vacuum tumbled for 1h, and smoked and cooked to 66oC. Externally, DK had lower L* and b* than PL and AV (P < 0.05). Internally, DK had higher L* than AV, which had higher L* than PL (P < 0.05). Peak
force to break was lower for DK than PL (P < 0.05). Consumers rated the appearance of PL lower than AV and DK for Overall Like, Like of Color, and Like of Texture, and AV lower than DK for Overall Like (P < 0.05). External and internal L* was lower and external a* higher for PHE than CON (P < 0.05). Consumer ratings for appearance of CON vs. PHE, respectively, was 6.0 vs. 6.7 for Overall Like, 5.9 vs. 6.8 for Like of Color and 6.0 vs. 5.6 for Like of Texture (P < 0.05). When tasting, consumers rated Like of Juiciness higher for PHE than CON (6.7 vs. 6.2, respectively; P < 0.05). Purge loss was lower for PHE than CON for DK, but higher for PHE than CON for PL (P < 0.05). Internal a* was increased by pH enhancement when using PL muscles (P < 0.05), but not when using AV or DK muscles (P > 0.05). Internal b* and elongation distance (elasticity) were decreased by pH enhancement when using DK muscles (P < 0.05), but not when using PL or AV muscles (P > 0.05). For consumer palatability
ratings, Overall Like and Like of Flavor was increased by pH enhancement when using PL muscles (P < 0.05), but not when using AV or DK muscles (P > 0.05). A trial determined the effect of pH enhancement with ammonium hydroxide on consumer acceptability of deli-style roast beef (RB), grilled chicken breast (CK), grilled pork loin (PK), beef prime rib (PR), beef pot roast (PT), and barbeque beef brisket (BR). One-half of the products served as CON, while the others were PHE to approximately 120% by weight with a solution containing water, ammonium hydroxide, carbon oxide, and salt. Consumer mean ratings for Overall Like were higher for PHE than CON for RB (6.90 vs. 6.49), CK (6.83 vs. 6.19), PK (7.13 vs. 5.33), PR (8.36 vs. 7.90), PT (8.15 vs. 7.76), and BR (7.50 vs. 6.92) (P < 0.05). Ratings for Like of Flavor, Like of Texture/Tenderness, and Like of Juiciness were higher for PHE than CON for all six products with the exception of Like of Juiciness for RB and Like of Flavor for PT (P >
0.05). When asked "Overall, which sample do you prefer?" a majority of consumers responded in favor of PHE: 60.5% for RB, 64.3% for CK, 89.1% for PK, 65.1% for PR, 60.2 for PT, and 64.1% for BR (P < 0.05).
Impacts
We have shown that pH enhancement improves visual appearance of hams made from pale, average, and dark muscles and improves eating quality of hams made from pale muscles. We have also shown that pH enhancement was effective at improving percent moisture retained after cooking, thus yielding a juicier end product. Moreover, pH enhancement was successful at improving consumer palatability ratings of various meat products, especially grilled pork loin. Improving meat quality would benefit both consumers and livestock producers. Because leaner animals produce meat which is more variable in quality, improvements in meat quality will enable consumers to enjoy tenderness and flavor along with enhanced nutrition and health. Livestock producers will benefit because improvements in meat quality will increase the demand for meat products.
Publications
- Nath, T. and Wulf, D. 2006. Trained and consumer evaluations of five different beef muscles with or without pH enhancement using ammonium hydroxide. J. Undergrad. Res. 4:47-57.
- Nath, T. M., Hand, C. D., Everts, A. J., Everts, A. K. R., Wulf, D. M. and Maddock, R. J. 2006. Trained and consumer evaluations of five different beef muscles with or without pH enhancement using ammonium hydroxide. Proc. Recip. Meat Conf., Champaign, IL.
- Everts, A. J., Wulf, D. M., Everts, A. K. R., Nath, T. M., Machado, T. and Maddock, R. J. 2006. Effects of pH-enhancement on chunked and formed hams processed from pale, average, and dark colored muscles. Proc. Recip. Meat Conf., Champaign, IL.
- Everts, A. J., Everts, A. K. R., Hand, C. D., Nath, T. M., Wulf, D. M. and Maddock, R. J. 2006. Effects of pH-enhancement on consumer ratings of various meat products. Proc. Recip. Meat Conf., Champaign, IL.
- Machado, T., Muench, L., Hand, C., Everts, A., Everts, A., Wulf, D. and Maddock, R. 2006. Quality and retail display life of ground beef produced using novel grinding technology. Proc. Recip. Meat Conf., Champaign, IL.
- Hand, C. D., Nath, T. M., Everts, A. J., Everts, A. K. R., Wulf, D. M., Henning, D. R. and Maddock, R. J. 2006. Effects of pH-enhancement on survivability and growth of E. coli on beef subprimals and steaks. Proc. Recip. Meat Conf., Champaign, IL.
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Progress 01/01/05 to 12/31/05
Outputs
A trial was conducted to determine the effect of pH enhancement with ammonium hydroxide on consumer acceptability of beef steaks. A 2 x 2 x 2 factorial design was used with two beef sources: Limousin cattle (LIMO) and Certified Angus Beef (CAB), two muscles: longissimus lumborum (LL) and semitendinosus (ST), and two treatments: control (CON) and pH-enhanced (PHE). Muscles designated for PHE were injected with a solution containing water, ammonium hydroxide, and salt. Steaks were evaluated for pH, Warner-Braztler shear force (WBS), and consumer ratings on a 10-pt scale using 288 consumers in a central-location consumer panel. Meat pH was raised from 5.39 for CON to 6.16 for PHE (P<0.05). A significant muscle by treatment interaction (P<0.05) for WBS indicated that pH enhancement had a greater effect on LL (CON=3.69 kg, PHE=2.01 kg) than on ST (CON=4.12 kg, PHE=3.36 kg). A significant source by treatment interaction (P<0.05) for WBS, Overall Like, Like of Tenderness,
and Like of Juiciness indicated that pH enhancement had greater effects on LIMO (CON vs. PHE=4.13 vs. 2.47 kg for WBS, 5.56 vs. 7.27 for Overall Like, 5.61 vs. 7.90 for Like of Tenderness, 5.41 vs. 7.43 for Like of Juiciness) than on CAB (CON vs. PHE=3.68 vs. 2.90 kg for WBS, 5.83 vs. 7.19 for Overall Like, 5.62 vs. 7.27 for Like of Tenderness, 5.62 vs. 7.07 for Like of Juiciness). pH enhancement resulted in higher Like of Flavor ratings (CON=5.51, PHE=7.00; P<0.05) and a greater consumer intent-to-purchase (CON=43%, PHE=71%; P<0.05). In a second trial, a Total Quality Management (TQM) system for producing beef steaks with exceptional palatability was developed to determine if this approach was superior to other methods of improving beef palatability. The TQM system included 12 critical control points: 1. Half-blood Jersey cows, 2. Half-blood Angus cows, 3. Marbling EPD in top 1% for maternal Angus sire, 4. Known-tender terminal sire, 5. Castration of males at birth, 6. No hormonal
implants, 7. Minimum 150 d on high-corn diet, 8. Maximum 20 mo age at harvest, 9. Maximum four h from feedlot to slaughter, 10. Pre-rigor skeletal separation at 12th/13th rib, 11. Delayed chilling for two h, and 12. Postmortem aging for 21 d. Longissimus lumborum (LL) and semitendinosus (ST) steaks were used to compare TQM beef to average U.S. beef (AVG), USDA Prime beef (PRIME), salt/phosphate-enhanced USDA Select beef (SPE), and pH-enhanced USDA Select beef (PHE). The AVG beef was obtained at retail stores in CA, KY, SD, and TX. The SPE beef was injected to 111% by weight with a solution of water, 4% sodium tripolyphosphate, and 3% salt. The PHE beef was injected with a solution of water, ammonium hydroxide, and salt. Consumers (n=204) 23 yr of age and older participated in a central-location sensory panel and rated cooked steaks on 10-point scales. For LL steaks, Overall Like ratings were 7.48 for PHE, 7.31 for TQM, 7.25 for PRIME, 6.98 for SPE, and 6.85 for AVG (diff>0.35,
P<0.05). For ST steaks, Overall Like ratings were 6.19 for PHE, 5.98 for TQM, 5.72 for SPE, 5.43 for AVG, and 5.08 for PRIME (diff>0.34, P<0.05).
Impacts
We have shown that pH enhancement of beef dramatically improves the palatability of cooked steaks. The improvements have been the greatest on leaner types of beef. We have shown that pH enhancement makes lean beef have consumer palatability ratings which are higher than non-enhanced fatter beef. Improving meat quality would benefit both consumers and livestock producers. Because leaner animals produce meat which is more variable in quality, improvements in meat quality will enable consumers to enjoy tenderness and flavor along with enhanced nutrition and health. Livestock producers will benefit because improvements in meat quality will increase the demand for meat products.
Publications
- Sweeter, K. K., Wulf,D. M. and Maddock, R. J. 2005. Determining the optimum beef ribeye size for retail consumers. J. Anim. Sci. 83:2598-2604.
- Wulf, D., Everts, A., Koger, T., Sweeter, K. and Maddock, R. 2005. Effectiveness of a total quality management (TQM) system at producing beef steaks with exceptional palatability (PACCP approach) compared to other methods of improving beef palatability. Proc. International Congr. Meat Sci. Technology, Baltimore, MA.
- Spronk, J., Wulf, D., Knudsen, D. and Maddock, R. 2005. Using serum chemistry profiles to predict beef tenderness for the purpose of on-line instrument grading. Proc. International Congr. Meat Sci. Technology, Baltimore, MA.
- Hand, C., Wulf, D. and Maddock, R. 2005. Using pH-enhancement of beef steaks to improve customer satisfaction. Proc. International Congr. Meat Sci. Technology, Baltimore, MA.
- Rohlfing, A., Wulf, D., Koger, T., McFarlane, B., Raynie, D. and Maddock, R. 2005. Use of high pressure for application of carbon monoxide in case-ready packaging systems for fresh beef. Proc. International Congr. Meat Sci. Technology, Baltimore, MA.
- Nath, T., Maddock, R. and Wulf, D. 2005. Consumer evaluations of bacon produced with or without nitrite and with or without ammonium hydroxide/carbon oxide enhancement. Proc. International Congr. Meat Sci. Technology, Baltimore, MA.
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