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Effects of bicarbonates on color stability and functional properties of ground beef
Abstracts
other muscle. A decrease (P b 0.05) in consumer acceptability of each palatability trait was observed as fat level decreased from Top Choice to Select. The semimembranosus showed the lowest acceptability scores for all the palatability traits. Overall and flavor acceptability were similar (P N 0.05) between LL, GM, and SV regardless of fat level. Consumer overall liking was correlated (P b 0.01) with consumer tenderness (r = 0.86) and juiciness ratings (r = 0. 71), but most highly correlated with flavor liking (r = 0.93). Conclusion: When tenderness was acceptable, flavor and juiciness play a major role in determining overall acceptability. Even when consumers scored tenderness low, as with the SM, superior flavor and juiciness could compensate and improve the overall liking and acceptability of beef. Overall liking of SV and GM from high quality carcasses was superior to LL from lower quality carcasses and comparable to LL from high quality carcasses. Therefore, results from this study showed that additional value could be captured by marketing those more underutilized cuts from high quality carcasses. Keywords: Beef, Consumer perception, Flavor, Marbling
475
no substrate and in the lactate systems and significantly affected (P b 0.05) by Fe+ 2, Fe+ 3 and time in the succinate system. In all the 3 systems, Oxymyoglobin concentration reduced with increasing Fe+ 2 concentration and time (P b 0.05 for each). The a*-value associated with redness was affected by Fe2 + (P b 0.05) and time (P b 0.05) in the no substrate system and in the lactate containing system. a* was affected by Fe+ 2, Fe+ 3 and time (P b 0.05 for each) in the succinate system. Conclusion: The non-heme iron redox forms will influence the redox stability of myoglobin. The value addition of metabolic substrates in beef homogenate will affect the redox reaction of inorganic iron forms and stabilize myoglobin redox stability. These results present scope for elucidating the mechanisms by which inorganic redox iron forms affect color stability of different raw meat products and their consumer acceptability at large. Keywords: Meat color, Myoglobin, Iron, Lactate, Succinate doi:10.1016/j.meatsci.2013.07.114
doi:10.1016/j.meatsci.2013.07.113
76 Redox stability of myoglobin influenced by inorganic redox iron forms and metabolic substrates in a beef homogenate system A. Purohit⁎, A. Mohan, S. Park, V. Sharma, Food Science and Technology, University of Georgia, Athens, United States Objectives: Beef color is a major intrinsic quality cue determining product purchase by consumers with discrimination against beef that is not red. The red color is generally associated with freshness. Iron, in both the nonheme and heme forms have been implicated to cause lipid peroxidation, the products of which promote metmyoglobin formation which degrades the redness and thus visual quality of beef. The effect of heme iron as an oxidant has been documented. Metabolic substrates which are intermediates of biochemical pathways such as malate, succinate, lactate and others have been shown to promote metmyoglobin reduction activity which stabilizes color. However, the effect of inorganic iron forms on color stability of fresh beef remains elusive. Thus, the objective of this study was to examine the effect of inorganic redox iron forms on the color stability of beef homogenate with or without the presence of metabolic substrates. Materials and methods: Beef M. Longissimus dorsi muscle was obtained from a local meat processor and frozen at −40 °C until further use. A model system was developed using Beef M. Longissimus dorsi muscle homogenate to mimic practical applications. The homogenate was prepared using 1:4 beef muscle and 0.04 M 3-(N-Morpholino) propane sulfonic acid (MOPS) buffer of pH 5.6. Ferrous chloride and Ferric chloride were used as sources of the inorganic iron. Potassium lactate and Sodium succinate were added at 2% levels dissolved in the buffer. The pH of all the homogenate systems was measured before treatments. The three systems studied were meat homogenate with buffer without any metabolic substrate, homogenate with buffer containing 2% succinate and homogenate with buffer containing 2% lactate. The homogenate was mixed with varying concentrations of ferric and ferrous ions at 0, 2, 4, 6 and 8 ppm level and incubated at 37 °C for 30 min. To determine the retail display color properties, color was measured for Hunter Lab color space values L*, a* and b* and reflectance in the visible range (400–700 nm) before and after incubation. The percentages of the three myoglobin redox forms: oxy-, deoxy- and met-myoglobin were estimated using the absorption and scattering coefficient (K/S) values from the reflectance at wavelengths specific to the three myoglobin redox forms. Results: Metmyoglobin formation was significantly affected by Fe+ 2 concentration and time of incubation (P b 0.05 for each) in the
77 Effects of bicarbonates on color stability and functional properties of ground beef S. Park⁎, A. Mohan, A. Purohit, V. Sharma, T. Jaico, Food Science and Technology, University of Georgia, Athens, United States Objectives: Color is the single most important factor of meat products that influences consumer buying decision and affects their perception of the freshness of the product. Sodium bicarbonate (SB) is known for improving the functional properties of the meat product. However, little is known how SB influences myoglobin redox status and meat color stability, and functional properties of the ground beef during storage and display. Therefore, the objective of this study was to determine the impact of the bicarbonate salt forms (sodium, potassium, and ammonium) on ground beef functional properties, myoglobin redox forms, and overall color stability during simulated retail display. Materials and methods: Ground beef (80% lean, 20% fat) was obtained from a local supplier (US Food, Inc., Augusta, GA), and was stored at −40 °C until further use. The ground beef was mixed with one of the following eight treatments (g/100 g water) combinations: A) Control (no bicarbonate; no salt); B) 0.5% Salt; C) 0.5% NaHCO3; D) 1% NaHCO3; E) 0.5% KHCO3; F) 1% KHCO3; G) 0.5% (NH4) HCO3; H) 1% (NH4)HCO3). After the treatment, ground beef was formed into patties and packaged on styrofoam trays with soaker pads and PVC wrapped. The trays were stored and displayed at 2–4 °C in a retail display case. The color measurements were recorded on days 1, 2, 3, 4, 6, and 7 using a HunterLab MiniScan EZ with illuminant D65, and 10° standard Observer. At each time of color determination, reflectance spectral values (400–700 nm) and CIE L*, a*, b* were measured at 3 random locations on each patty. The expressible moisture, internal cooked color, and cook yield were also determined on ground beef cooked in an aluminum tray to an internal temperature of 71 °C (160 °F) in a Blodgett oven. Results: Mean pH for ground beef treated with bicarbonate (treatments C to H) ranged from 7.14 to 7.91, compared to 5.61 for the control (A). CIE a* value, an indicator of meat “redness”, showed that control and salt treated ground beef were redder (p b 0.05) compared to all other samples (treatments C to H) up to 3 days of retail display and storage. However, on day 6 and 7, sodium bicarbonate treated ground beef was redder (p b 0.05) compared to all other treatments. Hue angle and saturation index showed the similar trend. With regard to cooked meat color, 0.5% Potassium and ammonium bicarbonate treated ground beef cooked interiors showed the lightest (highest L*) (p b 0.05). All three forms of bicarbonates treated ground
476
Abstracts
beef showed significantly higher (p b 0.05) Cooked yield and Expressible moisture (%) than the control. Treatment H i.e. 1% ammonium bicarbonate showed the most effective and was significantly different (p b 0.05) from all other treatments. Conclusion: Results from this study demonstrate that application of bicarbonate as non-meat ingredient in ground beef will influence the color life, increase the cook yield and moisture content. Since sodium and ammonium bicarbonate each influenced meat color, expressible moisture, and cook yield, further experiments need to be performed in order to optimize the levels of these treatments.
electron loss may be due to the NADH pool being depleted while reducing the reactive oxygen species. Another mechanism may be the oxidative damage of enzymes associated with metmyoglobin reduction by reactive oxygen species. Moreover, increased electron loss was associated with greater glycogen stores (evidenced by glycolytic potential) and reduced muscle pH, which contributed to increased lightness at the beginning of simulated retail display. Thus, it appears that reduced mitochondrial efficiency influences beef lean color and color stability. Increased feed efficiency through mitochondrial efficiency may result in fewer losses associated with discoloration of beef products at retail.
Keywords: Meat color, Bicarbonate, Cook yield, Cooked color Keywords: Beef, Color, Color stability, Electron transport, Mitochondria doi:10.1016/j.meatsci.2013.07.115 doi:10.1016/j.meatsci.2013.07.116 78 Influence of mitochondrial efficiency on beef lean color stability R.O. McKeitha,⁎, D.A. Kingb, A.L. Graysona, S.D. Shackelfordb, J.W. Savella, T.L. Wheelerb, aTexas A&M University, College Station, United States, b USDA-ARS US Meat Animal Research Center, Clay Center, United States Objectives: Loss of electrons in the electron transport chain has been implicated as a source of variation in feed efficiency of meat producing animals. The present study was conducted to evaluate the effects of electron loss during electron transport on beef lean color stability. Materials and methods: Beef carcasses (n = 91) were selected from a commercial beef processor and longissimus lumborum pH and marbling score were determined as the carcasses were presented for grading. Beef, loin, and strip loin subprimals were aged until 13 d postmortem, when longissimus lumborum steaks were cut for simulated retail display. Instrumental color attributes [lightness (L*), redness (a*), yellowness (b*), hue angle] were determined on d 0, 1, 4, 7, and 11 of simulated retail display. Overall color change from d 0 (ΔE) was calculated for d 1, 4, 7, and 11 of simulated retail display. Additional steaks were used for determination of electron loss from the electron transport chain, oxygen consumption, metmyoglobin reducing activity, glycolytic potential, and myoglobin concentration determination. Electron loss was determined as the percentage increase in fluorescence units resulting from incubating (37 °C for 20 min) isolated mitochondria in the presence of 2′-7′ dichlorofluorescein diacetate with succinate as a substrate for electron transport. Results: Longissimus lumborum steak lightness on d 0 of display was positively correlated (P b 0.05) to electron loss (r = 0.28), marbling score (r = 0.40), and glycolytic potential (r = 0.25). Myoglobin concentration (r = −0.41), metmyoglobin reducing activity (r = −0.51), oxygen consumption (r = -0.41), and muscle pH (r = -0.29), were negatively correlated (P b 0.05) to d 0 L* values. Redness (a*) on d 0 of display was negatively correlated (P b 0.05) to metmyoglobin reducing activity (r = −0.21), oxygen consumption (r = −0.28), and muscle pH (r = −0.35). Overall color change during 11 d of simulated retail display was associated (P b 0.05) with increased electron loss (r = 0.35) and decreased metmyoglobin reducing activity (r = −0.21), oxygen consumption (r = −0.22), and muscle pH (r = −0.32). Increased electron loss was associated (P b 0.05) with decreased metmyoglobin reducing ability (r = −0.23) and muscle pH (r = −0.39). Increased electron loss was also associated (P b 0.05) with increased glycolytic potential (r = 0.24) and marbling score (r = 0.26). Conclusion: These data suggest that greater electron loss is associated with decreased metmyoglobin reducing activity and, consequently, reduced beef lean color stability. Electrons lost during electron transport form reactive oxygen species which then must be reduced by the cell. Lower reducing ability associated with increased
79 Effects of injection enhancement with sodium tripolyphosphate, carrageenan, and sea salt on beef retail display properties and color stability V. Sharma, N. Lee⁎, G. Nagaraj, R. Singh, A. Mohan, Food Science & Technology, University of Georgia, Athens, United States Objectives: The application of ‘injection enhancement’ has been shown to improve beef tenderness and juiciness. The current industry practices of subjecting different quality grade beefs to the same enhancement strategies may not adequately represent differences in quality attributes and other additional problem associated with enhanced beef. The objective of this study was to assess the effects of injection enhancement on display color properties and sensory traits of beef strip loins of different quality grades. Materials and methods: Subprimals from USDA Choice and Select ((IMPS # 180 from A-maturity beef carcass) were randomly selected (n = 12) and assigned to one of the following injection enhancement treatments: A) Control (non-enhanced); B) 0.3% Sodium Tripolyphosphate (STPP) + 0.25% Carrageenan (CG) + 1% Sea Salt (SS); Treatment C) 0.3% STPP + 0.5% CG + 1% SS; and Treatment D) 0.3% STPP + 2.5% Potassium Lactate (PL) + 1% SS. The subprimals were enhanced at 110% of their green weight and the steaks were fabricated (2.54 cm thick) and packaged on styrofoam trays with soaker pads and PVC wrapped. The trays were stored and displayed under fluorescent lighting at 2–4 °C for 7 days for 0, 1, 2, 3, 4, 5, 6 and 7 days of retail display and storage. Instrumental color characteristics during retail storage and display were recorded using HunterLab MiniScan EZ. The experimental design was a split-plot design, with loin serving as experimental unit. The steaks served as the sub-plot and the data was analyzed using the Mixed Procedure (PROC MIXED) of SAS (SAS Institute, Inc., Cary, NC). Results: The display color properties for the choice steaks had higher (P b 0.05) L*, a*, and b*-values than the select steaks. The a*values for the choice steaks injected with treatment D exhibited increased redness than any other treatments and were significantly different (P b 0.05) from the select steaks. For select steak L*-values for all the treatments were significantly different (P b 0.05) from the control (P b 0.05). Visual score and the discoloration score also suggest that treatments C and D outperformed other treatments and were significantly different (P b 0.05) for both choice and select grade steaks. Choice quality grade steaks enhanced with treatment D had lower (P b 0.05) discoloration score than the select and outperformed select steaks in low discoloration during display days of 4, 5, 6, and 7. Conclusion: Results from these experiments suggest that injection-enhancement of meat with STPP, CG, SS, and PL in combination can effectively extend the color shelf-life of post-rigor beef by providing more reducing conditions for myoglobin, thus increasing
other muscle. A decrease (P b 0.05) in consumer acceptability of each palatability trait was observed as fat level decreased from Top Choice to Select. The semimembranosus showed the lowest acceptability scores for all the palatability traits. Overall and flavor acceptability were similar (P N 0.05) between LL, GM, and SV regardless of fat level. Consumer overall liking was correlated (P b 0.01) with consumer tenderness (r = 0.86) and juiciness ratings (r = 0. 71), but most highly correlated with flavor liking (r = 0.93). Conclusion: When tenderness was acceptable, flavor and juiciness play a major role in determining overall acceptability. Even when consumers scored tenderness low, as with the SM, superior flavor and juiciness could compensate and improve the overall liking and acceptability of beef. Overall liking of SV and GM from high quality carcasses was superior to LL from lower quality carcasses and comparable to LL from high quality carcasses. Therefore, results from this study showed that additional value could be captured by marketing those more underutilized cuts from high quality carcasses. Keywords: Beef, Consumer perception, Flavor, Marbling
475
no substrate and in the lactate systems and significantly affected (P b 0.05) by Fe+ 2, Fe+ 3 and time in the succinate system. In all the 3 systems, Oxymyoglobin concentration reduced with increasing Fe+ 2 concentration and time (P b 0.05 for each). The a*-value associated with redness was affected by Fe2 + (P b 0.05) and time (P b 0.05) in the no substrate system and in the lactate containing system. a* was affected by Fe+ 2, Fe+ 3 and time (P b 0.05 for each) in the succinate system. Conclusion: The non-heme iron redox forms will influence the redox stability of myoglobin. The value addition of metabolic substrates in beef homogenate will affect the redox reaction of inorganic iron forms and stabilize myoglobin redox stability. These results present scope for elucidating the mechanisms by which inorganic redox iron forms affect color stability of different raw meat products and their consumer acceptability at large. Keywords: Meat color, Myoglobin, Iron, Lactate, Succinate doi:10.1016/j.meatsci.2013.07.114
doi:10.1016/j.meatsci.2013.07.113
76 Redox stability of myoglobin influenced by inorganic redox iron forms and metabolic substrates in a beef homogenate system A. Purohit⁎, A. Mohan, S. Park, V. Sharma, Food Science and Technology, University of Georgia, Athens, United States Objectives: Beef color is a major intrinsic quality cue determining product purchase by consumers with discrimination against beef that is not red. The red color is generally associated with freshness. Iron, in both the nonheme and heme forms have been implicated to cause lipid peroxidation, the products of which promote metmyoglobin formation which degrades the redness and thus visual quality of beef. The effect of heme iron as an oxidant has been documented. Metabolic substrates which are intermediates of biochemical pathways such as malate, succinate, lactate and others have been shown to promote metmyoglobin reduction activity which stabilizes color. However, the effect of inorganic iron forms on color stability of fresh beef remains elusive. Thus, the objective of this study was to examine the effect of inorganic redox iron forms on the color stability of beef homogenate with or without the presence of metabolic substrates. Materials and methods: Beef M. Longissimus dorsi muscle was obtained from a local meat processor and frozen at −40 °C until further use. A model system was developed using Beef M. Longissimus dorsi muscle homogenate to mimic practical applications. The homogenate was prepared using 1:4 beef muscle and 0.04 M 3-(N-Morpholino) propane sulfonic acid (MOPS) buffer of pH 5.6. Ferrous chloride and Ferric chloride were used as sources of the inorganic iron. Potassium lactate and Sodium succinate were added at 2% levels dissolved in the buffer. The pH of all the homogenate systems was measured before treatments. The three systems studied were meat homogenate with buffer without any metabolic substrate, homogenate with buffer containing 2% succinate and homogenate with buffer containing 2% lactate. The homogenate was mixed with varying concentrations of ferric and ferrous ions at 0, 2, 4, 6 and 8 ppm level and incubated at 37 °C for 30 min. To determine the retail display color properties, color was measured for Hunter Lab color space values L*, a* and b* and reflectance in the visible range (400–700 nm) before and after incubation. The percentages of the three myoglobin redox forms: oxy-, deoxy- and met-myoglobin were estimated using the absorption and scattering coefficient (K/S) values from the reflectance at wavelengths specific to the three myoglobin redox forms. Results: Metmyoglobin formation was significantly affected by Fe+ 2 concentration and time of incubation (P b 0.05 for each) in the
77 Effects of bicarbonates on color stability and functional properties of ground beef S. Park⁎, A. Mohan, A. Purohit, V. Sharma, T. Jaico, Food Science and Technology, University of Georgia, Athens, United States Objectives: Color is the single most important factor of meat products that influences consumer buying decision and affects their perception of the freshness of the product. Sodium bicarbonate (SB) is known for improving the functional properties of the meat product. However, little is known how SB influences myoglobin redox status and meat color stability, and functional properties of the ground beef during storage and display. Therefore, the objective of this study was to determine the impact of the bicarbonate salt forms (sodium, potassium, and ammonium) on ground beef functional properties, myoglobin redox forms, and overall color stability during simulated retail display. Materials and methods: Ground beef (80% lean, 20% fat) was obtained from a local supplier (US Food, Inc., Augusta, GA), and was stored at −40 °C until further use. The ground beef was mixed with one of the following eight treatments (g/100 g water) combinations: A) Control (no bicarbonate; no salt); B) 0.5% Salt; C) 0.5% NaHCO3; D) 1% NaHCO3; E) 0.5% KHCO3; F) 1% KHCO3; G) 0.5% (NH4) HCO3; H) 1% (NH4)HCO3). After the treatment, ground beef was formed into patties and packaged on styrofoam trays with soaker pads and PVC wrapped. The trays were stored and displayed at 2–4 °C in a retail display case. The color measurements were recorded on days 1, 2, 3, 4, 6, and 7 using a HunterLab MiniScan EZ with illuminant D65, and 10° standard Observer. At each time of color determination, reflectance spectral values (400–700 nm) and CIE L*, a*, b* were measured at 3 random locations on each patty. The expressible moisture, internal cooked color, and cook yield were also determined on ground beef cooked in an aluminum tray to an internal temperature of 71 °C (160 °F) in a Blodgett oven. Results: Mean pH for ground beef treated with bicarbonate (treatments C to H) ranged from 7.14 to 7.91, compared to 5.61 for the control (A). CIE a* value, an indicator of meat “redness”, showed that control and salt treated ground beef were redder (p b 0.05) compared to all other samples (treatments C to H) up to 3 days of retail display and storage. However, on day 6 and 7, sodium bicarbonate treated ground beef was redder (p b 0.05) compared to all other treatments. Hue angle and saturation index showed the similar trend. With regard to cooked meat color, 0.5% Potassium and ammonium bicarbonate treated ground beef cooked interiors showed the lightest (highest L*) (p b 0.05). All three forms of bicarbonates treated ground
476
Abstracts
beef showed significantly higher (p b 0.05) Cooked yield and Expressible moisture (%) than the control. Treatment H i.e. 1% ammonium bicarbonate showed the most effective and was significantly different (p b 0.05) from all other treatments. Conclusion: Results from this study demonstrate that application of bicarbonate as non-meat ingredient in ground beef will influence the color life, increase the cook yield and moisture content. Since sodium and ammonium bicarbonate each influenced meat color, expressible moisture, and cook yield, further experiments need to be performed in order to optimize the levels of these treatments.
electron loss may be due to the NADH pool being depleted while reducing the reactive oxygen species. Another mechanism may be the oxidative damage of enzymes associated with metmyoglobin reduction by reactive oxygen species. Moreover, increased electron loss was associated with greater glycogen stores (evidenced by glycolytic potential) and reduced muscle pH, which contributed to increased lightness at the beginning of simulated retail display. Thus, it appears that reduced mitochondrial efficiency influences beef lean color and color stability. Increased feed efficiency through mitochondrial efficiency may result in fewer losses associated with discoloration of beef products at retail.
Keywords: Meat color, Bicarbonate, Cook yield, Cooked color Keywords: Beef, Color, Color stability, Electron transport, Mitochondria doi:10.1016/j.meatsci.2013.07.115 doi:10.1016/j.meatsci.2013.07.116 78 Influence of mitochondrial efficiency on beef lean color stability R.O. McKeitha,⁎, D.A. Kingb, A.L. Graysona, S.D. Shackelfordb, J.W. Savella, T.L. Wheelerb, aTexas A&M University, College Station, United States, b USDA-ARS US Meat Animal Research Center, Clay Center, United States Objectives: Loss of electrons in the electron transport chain has been implicated as a source of variation in feed efficiency of meat producing animals. The present study was conducted to evaluate the effects of electron loss during electron transport on beef lean color stability. Materials and methods: Beef carcasses (n = 91) were selected from a commercial beef processor and longissimus lumborum pH and marbling score were determined as the carcasses were presented for grading. Beef, loin, and strip loin subprimals were aged until 13 d postmortem, when longissimus lumborum steaks were cut for simulated retail display. Instrumental color attributes [lightness (L*), redness (a*), yellowness (b*), hue angle] were determined on d 0, 1, 4, 7, and 11 of simulated retail display. Overall color change from d 0 (ΔE) was calculated for d 1, 4, 7, and 11 of simulated retail display. Additional steaks were used for determination of electron loss from the electron transport chain, oxygen consumption, metmyoglobin reducing activity, glycolytic potential, and myoglobin concentration determination. Electron loss was determined as the percentage increase in fluorescence units resulting from incubating (37 °C for 20 min) isolated mitochondria in the presence of 2′-7′ dichlorofluorescein diacetate with succinate as a substrate for electron transport. Results: Longissimus lumborum steak lightness on d 0 of display was positively correlated (P b 0.05) to electron loss (r = 0.28), marbling score (r = 0.40), and glycolytic potential (r = 0.25). Myoglobin concentration (r = −0.41), metmyoglobin reducing activity (r = −0.51), oxygen consumption (r = -0.41), and muscle pH (r = -0.29), were negatively correlated (P b 0.05) to d 0 L* values. Redness (a*) on d 0 of display was negatively correlated (P b 0.05) to metmyoglobin reducing activity (r = −0.21), oxygen consumption (r = −0.28), and muscle pH (r = −0.35). Overall color change during 11 d of simulated retail display was associated (P b 0.05) with increased electron loss (r = 0.35) and decreased metmyoglobin reducing activity (r = −0.21), oxygen consumption (r = −0.22), and muscle pH (r = −0.32). Increased electron loss was associated (P b 0.05) with decreased metmyoglobin reducing ability (r = −0.23) and muscle pH (r = −0.39). Increased electron loss was also associated (P b 0.05) with increased glycolytic potential (r = 0.24) and marbling score (r = 0.26). Conclusion: These data suggest that greater electron loss is associated with decreased metmyoglobin reducing activity and, consequently, reduced beef lean color stability. Electrons lost during electron transport form reactive oxygen species which then must be reduced by the cell. Lower reducing ability associated with increased
79 Effects of injection enhancement with sodium tripolyphosphate, carrageenan, and sea salt on beef retail display properties and color stability V. Sharma, N. Lee⁎, G. Nagaraj, R. Singh, A. Mohan, Food Science & Technology, University of Georgia, Athens, United States Objectives: The application of ‘injection enhancement’ has been shown to improve beef tenderness and juiciness. The current industry practices of subjecting different quality grade beefs to the same enhancement strategies may not adequately represent differences in quality attributes and other additional problem associated with enhanced beef. The objective of this study was to assess the effects of injection enhancement on display color properties and sensory traits of beef strip loins of different quality grades. Materials and methods: Subprimals from USDA Choice and Select ((IMPS # 180 from A-maturity beef carcass) were randomly selected (n = 12) and assigned to one of the following injection enhancement treatments: A) Control (non-enhanced); B) 0.3% Sodium Tripolyphosphate (STPP) + 0.25% Carrageenan (CG) + 1% Sea Salt (SS); Treatment C) 0.3% STPP + 0.5% CG + 1% SS; and Treatment D) 0.3% STPP + 2.5% Potassium Lactate (PL) + 1% SS. The subprimals were enhanced at 110% of their green weight and the steaks were fabricated (2.54 cm thick) and packaged on styrofoam trays with soaker pads and PVC wrapped. The trays were stored and displayed under fluorescent lighting at 2–4 °C for 7 days for 0, 1, 2, 3, 4, 5, 6 and 7 days of retail display and storage. Instrumental color characteristics during retail storage and display were recorded using HunterLab MiniScan EZ. The experimental design was a split-plot design, with loin serving as experimental unit. The steaks served as the sub-plot and the data was analyzed using the Mixed Procedure (PROC MIXED) of SAS (SAS Institute, Inc., Cary, NC). Results: The display color properties for the choice steaks had higher (P b 0.05) L*, a*, and b*-values than the select steaks. The a*values for the choice steaks injected with treatment D exhibited increased redness than any other treatments and were significantly different (P b 0.05) from the select steaks. For select steak L*-values for all the treatments were significantly different (P b 0.05) from the control (P b 0.05). Visual score and the discoloration score also suggest that treatments C and D outperformed other treatments and were significantly different (P b 0.05) for both choice and select grade steaks. Choice quality grade steaks enhanced with treatment D had lower (P b 0.05) discoloration score than the select and outperformed select steaks in low discoloration during display days of 4, 5, 6, and 7. Conclusion: Results from these experiments suggest that injection-enhancement of meat with STPP, CG, SS, and PL in combination can effectively extend the color shelf-life of post-rigor beef by providing more reducing conditions for myoglobin, thus increasing