Retail display evaluation of steaks from select beef strip loins injected with a brine containing 1% ammonium hydroxide. Part 2: Cook yield, tenderness, and sensory attributes

The impact of 2 different brines on the palatability and tenderness of select beef strip loin steaks was evaluated. Brines were differentiated by the type of alkaline agent, 4.5% sodium-based phosphate (control brine; CON) or 1% ammonium hydroxide (ammonium hydroxide treatment; AHT), incorporated into the formula. Injected steaks were placed in high oxygen (80% O(2)/20% CO(2)) MAP, stored 4 d at 4 °C in dark storage to simulate transportation, and then placed in retail display. Steaks were selected randomly on day 0, 7, and 14 retail display to measure pH, cook loss, shear force, and sensory characteristics. The pH for AHT steaks (pH 5.96) was slightly higher than CON steaks (pH 5.86; P < 0.05). Cook loss was lower (21%) for CON than AHT steaks (23%). There was neither a treatment nor day effect on tenderness as measured by Warner-Braztler shear force (P > 0.05). Sensory evaluation indicated that on day 0, retail display the initial juiciness, sustained juiciness, tenderness 1st impression, tenderness overall impression, and connective tissue in AHT steaks was not different from CON steaks (P > 0.05). A day effect (decrease) for those sensory parameters was observed only for sustained juiciness (P < 0.05). AHT steaks were rated higher in cooked beef flavor while CON steaks were higher in peppery and salty flavor. There was no difference in soapy and ammonia intensity between treatments. Results indicated that despite lower performance in cook loss the replacement of 4.5% sodium-based phosphate in a meat injection brine with 1% ammonium hydroxide produced a beef loin steak with comparable tenderness and palatability. Practical Application: The research in this study compares steaks that have been injected with a commercial brine formulated with sodium phosphates to steaks that have been injected with a brine where the sodium phosphate in the formulation was replaced with 1% ammonium hydroxide. Ammonium hydroxide is an USDA-FSIS approved ingredient in brines injected into fresh meats. Successful replacement of sodium phosphate with ammonium hydroxide would allow processors to significantly reduce the sodium content of injected fresh meat.     

Response surface modeling to predict fluid loss from beef strip loins and steaks injected with salt and phosphate with or without a dehydrated beef protein water binding adjunct

This study was conducted using response surface methodology to predict fluid loss from injected beef strip steaks as influenced by levels of salt and sodium phosphates (SP) in the injection brine. Also, a beef-based dehydrated beef protein (DBP) water binding ingredient was evaluated. Paired U.S. select beef strip loins were quartered before being injected with 110% of initial weight with brines containing various concentrations of salt and SP (CON) or salt, SP and 5% DBP. Steaks were sliced, overwrapped and stored in the dark for 4 d. Purge values ranged from 0.6% to 4.6% for CON and 0.3% to 2.1% for DBP. Fluid losses when accounting for the fluid lost from injection to slicing were as high as 6.8% for CON brines, but only 2.8% for DBP brines. The equations generated here and the DBP product could help producers achieve acceptable purge while reducing sodium use.     

Evaluation of a dehydrated beef protein to replace sodium-based phosphates in injected beef strip loins

A dehydrated beef protein (DBP) was evaluated as a replacement for the phosphate added to beef injection brines. U.S. Select strip loins (n=20) were injected to 110% of their initial weight with a brine containing 3.6% salt and 4.5% sodium phosphate (CON) or 3.6% salt and 5% dehydrated beef protein (DBP). DBP loins had less fluid loss after 30 min. Steaks from both treatments lost similar amounts of fluid during storage. Total fluid loss was lower for DBP injected product. Lipid oxidation (TBARS) products were 0.23-0.60 mg/Kg higher for DBP steaks. DBP steaks were slightly less red than CON steaks according to instrumental measurements. Sensory panel evaluation, however, indicated no differences in redness. DBP steaks were less tender according to trained sensory panel. Results indicated the DBP to be effective in increasing brine retention and a viable alternative to phosphates when used in brines injected into beef strip steaks.     

RETAIL APPEARANCE OF ELECTRICALLY STIMULATED BEEF

Top round steaks (adductor) and ground beef from the top round were obtained from both sides of ten U.S. Choice carcasses. Left sides were electrically stimulated (ES) with 17 impulses (1.8 set duration, 1.8 set interval) of 550 volts of alternating current at 5 amps. Steaks and ground beef from top rounds from nonstimulated right sides served as control (CON) samples. Steaks and ground beef were displayed under simulated retail conditions for 4 and 3 days, respectively. Steaks were weighed prior to and at the termination of the display interval to determine percentage weight loss. Samples for microbiological evaluation were obtained prior to and at the termination of the display interval. No significant differences were observed for muscle color, surface discoloration or overall appearance for samples of ground beef at any retail display interval. With one exception, muscle color was brighter and surface discoloration was reduced for round steaks from ES sides. Few significant differences in overall appearance were observed between ES and CON samples during the display period. No significant differences between ES and CON samples were observed for bacterial counts either initially or at the termination of the display period for either steaks or ground beef samples. Percentage weight loss was not significantly different between ES and CON steaks. These data suggest that electrical stimulation may enhance, and certainly does not detract from, the appearance of round steaks displayed under retail market conditions.     

Evaluation of 0.1% Ammonium Hydroxide to Replace Sodium Tripolyphosphate in Fresh Meat Injection Brines

ABSTRACT:  Paired USDA Select beef strip loins ( n  = 10), aged 2 d, were injected with either an alkaline-based (3.6% sodium chloride, 1% Herbalox seasoning, adjusted to pH 10 with ammonium hydroxide [approximately 0.1%, FFC grade]) or a phosphate-based (3.6% sodium chloride, 1% Herbalox seasoning, 4.5% sodium tripolyphosphate) brine. Steaks were evaluated for 19 d. Overall, phosphate-injected steaks performed better than alkaline-injected steaks with respect to cook yield, water holding capacity, lipid oxidation, color stability, tenderness, and juiciness. Phosphate-injected steaks also had less purge than alkaline-injected steaks, as confirmed by composition analysis. Phosphate-injected steaks were higher in moisture and ash content, and were nearly 2% lower in protein content. Alkaline-injected steaks had significantly lower aerobic (approximately 1 log lower) and anaerobic (approximately 2 log lower) plate counts. Final meat pH probably contributed to the differences observed between treatments. The final pH of phosphate-injected steak was 5.99 while that of alkaline-injected steak was 5.73. Further research should be conducted to determine the concentration of ammonium hydroxide needed in the alkaline-based brine to increase the final meat pH to similar levels found in the phosphate-injected steaks.     

Antimicrobial effect of ammonium hydroxide when used as an alkaline agent in the formulation of injection brine solutions

Paired U.S. Department of Agriculture Select strip loins were injected with either a conventional brine (4.5% potassium and sodium polyphosphate blend [Brifisol 750], 3.6% NaCl, 1% Herbalox seasoning HT-S, and 90.9% ice water) or an ammonium hydroxide (AH) brine (1% AH, 3.6% NaCl, 1% Herbalox seasoning HT-S, and 94.4% ice water). The steaks were sliced, high-oxygen modified atmosphere packaged, placed at 5°C in dark storage for 5 days, and then transferred to a retail display at 5°C for another 14 days. Steaks injected with AH brine appeared to have lower counts of psychrotrophic, mesophilic, and gram-negative bacteria. Immediately after injection, there was ～1 log CFU/g difference between treatments in gram-negative bacterial counts. No differences in coliform and lactic acid bacterial counts were found.     

Influence of Injection, Packaging, and Storage Conditions on the Quality of Beef and Bison Steaks

The combined effects of injection, packaging (modified atmosphere packaging [MAP] with 70% O₂/ 30% CO₂ and vacuum packaging [VP]), storage temperature (‐1 °C and +4 °C), and storage time on the color, microbial and oxidative stability of beef and bison longissimus lumborum (LL) steaks were investigated. Beef LL steaks in MAP retained their bright red color longer than bison steaks. Bison steaks developed higher 2‐Thiobarbituric acid reactive substances (TBARS) during storage, and this might have influenced the resulting rapid loss of redness from the bloomed meat. Storage at ‐1 °C in MAP provided greater color stability and a longer storage life for both meat species studied. Injection of salt/phosphate had a beneficial effect on the color stability of steaks during retail display; however, this positive effect was more pronounced for bison steaks compared with those of beef. Steaks stored overnight under MAP before retail display maintained the highest a* values for up to 5 d compared with those stored under vacuum. MAP‐OV steaks generally maintained the highest OMB content for up to 5 d during retail display compared with those stored under vacuum. Nevertheless, OMB levels were significantly (P < 0.05) lower in bison steaks compared with those of beef irrespective of packaging treatments. Injected steaks and those stored at ‐1 °C had significantly (P < 0.05) higher OMB levels compared with non‐injected counterparts and those stored at +4 °C, respectively. MAP is an excellent option for short‐term storage due to its positive effects on meat color, but for longer storage, VP may be necessary. Storing meat under vacuum and then placing it under MAP just before retail display might be another option to increase shelf life.     

Effects of Electrical Stimulation and Hot Boning on Color Stability of Aerobic and Vacuum Packaged Restructured Beef Steaks

Color stability of restructured beef steaks processed from beef boned 4 hr postmortem (HB) and 96 hr postmortem (CB) was determined using a Hunter color difference meter and a semi-trained color evaluation panel. Steaks were formulated using ground tenderized (2.5 cm) restructurable meat (75% of formulation), salted preblended meat (3% NaCl + 0.267% BHA, 25% of formulation) and enough ground fat to form steaks of 10% fat. Steaks were aerobically wrapped and vacuum packaged. Hunter L, a, b, a/b values and color panel scores during a 7-day retail display revealed that HB steaks had superior color stability. This was attributed to the ability of NaCl to inhibit glycolysis in the HB preblended meat and to act as a prooxidant of myoglobin in the CB preblended meat.     

Effect of Prerigor Pressurization on the Retail Characteristics of Beef

Loin steaks were obtained from eight utility cows and ground beef from the bottom round of four choice steers. One side was randomly assigned to be prerigor pressurized (PRP) and the other side served as control (CON). Steaks and ground beef were displayed under simulated retail conditions for 5 and 3 days, respectively. PRP significantly improved lean color of the steaks for the first 4 days of display period. PRP steaks were significantly less discolored at the 5th day. No significant difference for any of the measured traits was observed for samples of ground beef. PRP had no detrimental effect on the case-life of steaks or ground beef.     

Color and thiobarbituric acid values of cooked top sirloin steaks packaged in modified atmospheres of 80% oxygen, or 0.4% carbon monoxide, or vacuum

Case-ready fresh beef is typically packaged in a modified-atmosphere with approximately 80% oxygen and 20% carbon dioxide. Recently, USDA approved distribution of fresh meats in a master bag system using 0.4% carbon monoxide (CO). This study compared effects of packaging system (vacuum, 80% oxygen, 0.4% carbon monoxide), fresh meat storage time (7-21 days) and cooking temperature (49-79 °C) on extent of myoglobin denaturation, color and rancidity in cooked top sirloin steaks. Steaks packaged in 80% oxygen or CO retained desirable red color for 14 and 21 days storage, respectively. Steaks stored in 80% oxygen exhibited the greatest TBA values and myoglobin denaturation at all storage times and cooking temperatures. Steaks stored in high oxygen developed brown interior color at internal temperatures as low as 57 °C, the premature browning effect. Premature browning and rancidity associated with steaks packaged in 80% oxygen was prevented by packaging in 0.4% CO or vacuum.     

ENHANCEMENT EFFECTS ON SENSORY AND RETAIL DISPLAY CHARACTERISTICS OF BEEF ROUNDS

Beef round roasts were injected (to 110% of original weight) to result in 0.4% sodium chloride and 0.4% phosphate on a finished weight basis. Steaks from enhanced roasts were more (P<0.05) juicy, tender and salty than those from control roasts. However, enhancement had a detrimental effect on the color of the steaks during retail display. After two days in display, enhanced steaks had lower visual color scores indicating darkening and discoloration. At 4 days, a* and b* values were lower for enhanced steaks indicating that they were less red and yellow than controls. Aerobic plate counts suggested that enhanced steaks were more susceptible to microbial growth during retail display. Although enhancement positively affected sensory characteristics, the negative effect of a shortened shelf-life was apparent.     

Boning Methods and Binders Affect Bind and Sensory Characteristics of Structured Beef

Steaks, fabricated with hot- (HB) or cold-boned (CB) beef and structured with salt/phosphate (SP), sodium alginate (ALG), or ALG and albumin, were packaged aerobically and anaerobically and displayed at 2°C for up to 30 days to determine effects of boning methods and binders on structured steak properties. Using SP and CB meat resulted in darker (p< 0.05) non-bloomed and bloomed steaks. Adding albumin had little effect on changing color of ALG steaks. Steaks with stronger cohesion (p<0.05) were produced when SP was used. Structured steaks fabricated with CB meat were more tender than those made using HB meat. In addition, steaks made with either meat type exhibited similar binding properties (p<0.05).     

Color, lipid oxidation, sensory quality, and aroma compounds of beef steaks displayed under different levels of oxygen in a modified atmosphere package

High oxygen modified atmosphere packaging (MAP) is currently used by the industry to maintain an attractive color in fresh meat. However, it can also promote lipid oxidation and sensory changes. The aim of this study was to compare the quality of beef steaks displayed under different levels of oxygen. For that purpose, meat was stored with 50%, 60%, and 80% of oxygen for 4 and 8 d at retail conditions. A control treatment with steaks vacuum packaged, without exposure to retail display, was included, and color, lipid oxidation, organoleptic characteristics, and aroma compounds were analyzed. Steaks displayed under high oxygen MAP with 50% of oxygen showed the lowest color stability, according to hue values. Higher oxygen levels did not necessarily correspond with higher rancidity levels in the raw meat. Thiobarbituric Acid Reacting Substances (TBARS) values were higher than 2.2 mg malonaldehyde (MDA)/kg muscle in all the samples displayed for 8 d at retail conditions. These samples exhibited the highest intensities of rancid and the least intense beef odors and flavors. The ketones: 2,3-butanedione, 2-octanone, 2,3-pentanedione, 2-heptanone, 4-methyl-2-pentanone, and the aldehydes: pentanal, 2-methyl-butanal, and 2-furfurylthiol, 1-octen-3-ol and 2-methylpropyl-acetate, were proposed as candidates for the aroma differences between the cooked beef steaks stored under vacuum and high oxygen packs. PRACTICAL APPLICATION: High oxygen modified atmosphere packaging (MAP) is used to increase shelf-life and color at the retail level. However, oxygen deteriorates faster some quality attributes, being a contributor to lipid oxidation that could be perceived at consumption. This study attempts to find the best gas composition in a MAP in order to maintain the color, minimizing the oxidation. Aromatically relevant chemicals have been analyzed by gas olfactometry-gas chromatography as a key to measure beef oxidation after display.     

Dietary vitamin E supplementation effects on the color and sensory characteristics of enhanced beef steaks

The objective of this study was to evaluate the effects of dietary vitamin E supplementation on characteristics of enhanced beef cuts during retail display. Twelve steers were fed either a control (E-) diet or a diet supplemented with dl-alpha tocopheryl acetate (E+) for 117 days prior to slaughter. Paired strip loins, clods, and inside rounds served as the control (C) or were pumped (P) to 110% of raw weight to contain 0.4% sodium chloride and 0.4% phosphate on a finished weight basis. Steaks were cut (2.5 cm) for sensory evaluation and retail display. No flavor or texture differences existed in strip steaks due to vitamin E. Enhanced steaks were more tender, juicy and salty than controls, however they discolored more rapidly than did controls. Steaks from supplemented cattle were slightly, but significantly, less discolored, indicating that vitamin E may provide some improvements in color stability of enhanced meat products. Vitamin E supplementation may improve short term color stability (up to 2 days in display) of retail beef enhanced by injection of a salt-phosphate solution.     

Influence of different gas compositions on the short-term storage stability of mother-packaged retail-ready lamb packs

Longissmus dorsi muscles were removed from Suffolk cross-breed lambs (aged 4-9 months) and cut into steaks. Lamb steaks were over-wrapped on trays and placed in vacuum pack bags. Bags were divided into 3 groups and flushed with gas mixtures containing 100:0, 90:10 or 80:20/CO(2):N(2). Mother packed lamb bags were stored for 4 days (T2) and 7 days (T3), respectively, in darkness at 4 °C, prior to retail display. The effect of aerobic packaging alone on lamb meat quality was used as the control (T1). Under retail display, all over-wrapped trays were held under refrigerated conditions (4 °C, 616 lx) for up to 8 days. Steaks were assessed for microbial growth, oxidative and colour stability as well as pH every 2 days. Mother-packing in 100:0/CO(2):N(2) was the most effective way of extending the storage life of retail ready lamb prior to display, particularly over longer storage periods. TVCs for T3 lamb meat using all gas compositions remained below 2.0×10(6) CFUs/g meat up until day 6 compared to day 4 in both T1 and T2 lamb. Lipid oxidation in lamb mother-packed for 7 days occurred at a faster comparative rate than discolouration and microbial growth and was the major determinant of shelf-life. However, under simulated retail display in aerobic packages, TBARS values did not increase significantly. There was no significant difference between Hunter 'a' values for T3 lamb meat and the control, but T3 meat mother-packed in 100:0/CO(2):N(2) had higher 'a' values than those of the control and T3 meat packed in other gas compositions. Lamb steaks in T3 previously mother-packed in 100:0/CO(2):N(2) were also significantly (p<0.05) higher than those of T2 on day 0. T3 meat also maintained initial colour values over those of the control.     

Tenderness and Retail Display Characteristics of Beef Tenderloin Steaks Comparing Kidney Fat Removal Times Under Different Processing and Storage Systems

The effects of electrical stimulation, kidney fat removal time, tenderloin removal time, and storage and packaging treatment on tenderness and retail display characteristics of beef tenderloin steaks were studied. Electrical stimulation increased overall desirability scores on days 2 through 4 of retail display. Steaks from sides that had kidney and pelvic fat removed prior to chilling had higher Warner-Bratzler shear force values, darker muscle color and higher retail evaluations for overall desirability on days 2 through 4 of display than did steaks from conventionally dressed sides. Tenderloin steaks that were vacuum packaged and stored 14 days had higher bacterial counts, more uniform lean color and less visual purge in the retail package than did steaks retail displayed immediately after tenderloin removal.     

Effects of enhancement with varying phosphate types and concentrations, at two different pump rates on beef biceps femoris instrumental color characteristics

The effect of enhancing beef biceps femoris muscles (n=45) with solutions comprising 2.0% sodium chloride and either sodium hexametaphosphate (SHMP), sodium tripolyphosphate (STPP), or tetrasodium pyrophosphate (TSPP) at either 0.2% or 0.4% of product weight on instrumental color during simulated retail display was investigated. All solutions were injected into muscle samples at either 112% (12% pump) or 118% (18% pump) of raw product weight. Muscles treated with all three phosphate types had lower (P<0.05) L* and b* values compared to untreated muscles (CNT). Steaks enhanced with STPP had similar (P>0.05) a* values as CNT, whereas SHMP- and TSPP-treated steaks generally had lower a* values than CNT. Across phosphate type, excluding day 3 of display, steaks treated with phosphate at 0.4% had similar (P>0.05) a* values as CNT, whereas those with 0.2% phosphate addition had lower (P<0.05) a* values than CNT. Across five days of display, STPP maintained higher (P<0.05) a* values than steaks treated only with sodium chloride, whereas SHMP did not differ (P>0.05) from sodium chloride-treated steaks. While STPP maintained a similar (P>0.05) saturation index as CNT, SHMP and TSPP generally had decreased (P<0.05) vividness during display. Additionally, excluding day 3 of display, phosphate concentration at 0.4% maintained similar vividness as CNT, whereas 0.2% phosphate concentration caused decreased (P<0.05) vividness, compared to CNT. The 630/580nm ratio results indicated that SHMP had less (P<0.05) oxymyoglobin than CNT throughout display. Disregarding day 3 of display, both STPP and TSPP had similar (P>0.05) oxymyoglobin proportions as CNT. These results indicate that STPP was the most effective phosphate type for maintaining color. Additionally, 0.4% phosphate concentrations can maintain color better than 0.2% phosphate concentrations. However, none of the phosphate/salt combinations produced superior color, compared to untreated steaks.     

Physical and Sensory Characteristics of Vacuum Packaged Beef Round Steaks as Influenced by Postmortem Age and Storage Temperature

Two steaks were removed from the semitendinosus, semimembranosus and biceps femoris muscles at 3, 6 or 9 days postmortem and vacuum packaged. Steaks were stored for 48 hr at 2°C or 7°C before retail display. Steaks cut at 3 days had less (P < 0.05) surface discoloration than those removed at 6 or 9 days. In most comparisons, steaks removed at 3 days were more desirable (P < 0.05) in overall appearance than steaks removed at either 6 or 9 days and stored at either temperature. Storage temperature did not accelerate lean color development for vacuum packaged beef round steaks. With increasing time postmortem before fabrication into steaks, longer storage periods may be needed before display to allow devet opment of proper lean color.     

Effects of Preslaughter Exercise, Electrical Stimulation, Type of Packaging Tray, Display Temperature, and Time on Acceptance and Shelflife of Beef Steaks

Eight steers, of which four were exercised prior to slaughter, were slaughtered and one side of each carcass electrically stimulated (ES). Steaks from combined wingrib and sirloin were packaged in two types of plastic foam trays, overwrapped with PVC and displayed in refrigerated display cabinets either at 0°C or 5°C meat surface temperature. Display temperature and period of display significantly influenced shelflife and overall appearance of steaks. ES enhanced tenderness and improved muscle color but caused more weight loss during display when compared with steaks from unstimulated carcasses. All factors investigated had a significant influence on percentage weight loss during display while stress and tray depth also negatively influenced cooking weight loss encountered during cooking.     

Effects of Various Phosphates on the Palatability, Appearance and Storage Traits of Flaked and Formed Restructured Beef Steaks

Seven blends (9.1 kg raw meat) were formulated with 0.75% NaCl and 0.25% or 0.5% sodium tripolyphosphate (STP), sodium hexa-metaphosphate (SHMP) or sodium acid pyrophosphate (SAPP). Steaks from all blends were “slightly” to “moderately” desirable in flavor and overall satisfaction scores. Steaks made with STP had higher shear force values and work required to shear values than all other restructured steaks indicating an increase in binding occurred with added STP. Restructured steaks formulated with 0.5% STP or SHMP had more desirable raw color scores than the control or steaks made with SAPP. Storage life of all phosphate added restructured steaks was past 90 days frozen storage, and steaks containing STP had thiobarbituric acid values below 1.0 at 120 days storage.