Effect of Antioxidants on Lipid Stability in Restructured Beef Steaks

Two natural antioxidant formulations–containing mixed tocopherols, ascorbyl palmitate and citric acid–and TBHQ were evaluated in restructured beef steaks formulated to contain 18% fat and 0.75% NaCl. Lipid oxidation was monitored over 12 months of frozen storage. TBHQ significantly (p < 0.05) lowered TBA numbers in raw and freshly cooked samples and in samples that were cooked and held 4 hr at 4°C. Natural antioxidants provided significant (p <0.05) protection in freshly cooked meat and were as effective as TBHQ in retarding lipid oxidation. Sensory evaluation and GC quantitation of hexanal were also used to monitor oxidation but the correlation between the three methods was not significant.     

Color and Color Stability of Frozen Restructured Beef Steaks: Effect of Processing Under Gas Atmospheres with Differing Oxygen Concentration

Restructured beef steaks were manufactured under gas atmospheres with differing oxygen concentration and subsequently vacuum-packaged. The effect of the different gas atmospheres on the color and color stability of frozen restructured beef steaks initially and at 1-month intervals for three months was investigated. Overall metmyoglobin concentrations for restructured beef steaks were not different (P > 0.05) from that of the intact steaks either initially or over storage time. The rates of overall metmyoglobin formation increased when oxygen concentration of the gas atmosphere was increased. Restructured steaks manufactured using pure carbon dioxide gas had the least amount of overall discoloration both initially and over storage time.     

Color and Its Stability in Restructured Beef Steaks during Frozen Storage: Effects of Various Binders

Color and its stability were evaluated in restructured steaks made with various binders (calcium alginate, crude myosin extract, whey protein concentrate, wheat gluten, soy isolate or surimi) vs controls (intact ribeye muscle, restructured steaks with no additives or with NaCl and sodium tripolyphosphate). Steaks made with various binders showed similar effects on initial surface metmyoglobin concentration and sensory color attributes, except steaks made with calcium alginate or soy isolate protein. During 12-wk frozen storage, steaks made with various binders (except soy protein isolate) had similar color stabilities.     

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.     

Color and Color Stability of Frozen Restructured Beef Steaks: Effect of Sodium Chloride, Tripolyphosphate, Nitrogen Atmosphere, and Processing Procedures

This study investigated the effect of mixing and grinding, tempering, addition of sodium chloride and sodium tripolyphosphate and processing under a nitrogen atmosphere on the color of restructured beef steaks initially and at 1-month intervals for 3 months of frozen storage. Mixing and grinding and manufacture under a nitrogen atmosphere had the greatest detrimental effect on the extent of discoloration initially; this was probably due to low oxygen concentration. Tempering and the addition of sodium chloride without sodium tripolyphosphate produced the most rapid increase in rate of discoloration during frozen storage. Tripolyphosphate partially counteracted the detrimental effect of sodium chloride, however, this effect did not appear to be due to the higher pH produced by the phosphate or the chelating ability of the phosphate. Surface discoloration and overall color were highly correlated with surface metmyoglobin (r= -0.87) and overall met-myoglobin (r= -0.94).     

Antioxidants in Restructured Beef/Pork Steaks

The effects of added antioxidants on restructured combination (50:50) beef-pork steaks were studied. Steaks were formulated to contain 20% fat and 0.75% salt. Antioxidants used at a 0.02% level (based on fat content of meat) were butylated hydroxyanisole (BHA), tertiary butyl hydroquinone (TBHQ), and a combination of BHA and TBHQ. Cooked steaks were evaluated for sensory properties and overall acceptability, initially and after 4, 8, 12, 16, an 20 wk of freezer storage. Steaks were also evaluated after the various storage times for 2-thiobarbituric acid (TBA) values, subjective color by panel evaluation, objective color with the Hunter color difference meter, tensile strength, shear value and cooking loss. Flavor and overall acceptability were significantly better in treated samples as compared to control samples. BHA was more effective in protecting color and TBHQ was more effective in protecting flavor (P<0.05). All treated samples showed lower TBA values than control samples (P<0.05).     

Restructured Beef Steaks from Hot-Boned and Cold-Boned Carcasses

Restructured steaks were manufactured from paired hot-boned (HB) and conventionally chilled beef (CB) rounds from carcasses that averaged USDA Good, yield grade 2. Salt (0.75%) was added to half of each HB and CB treatment during mixing. Panelists in triangle tests could not distinguish between HB and CB restructured products. Trained sensory panel scores confirmed triangle test results for flavor, texture and acceptability when restructured HB and CB steaks were compared. Panelists in triangle tests detected a difference (P < 0.01) between salted and unsalted restructured steaks. Trained panelists rated salted samples higher (P < 0.05) for flavor, texture, acceptability and cooking loss, but lower for discoloration.     

Effects of Hot-Boning and Particle Thickness on Restructured Beef Steaks

Restructured steaks were made using hot-boned or aged beef made from sliced particles (2.5 mm or 5.0 mm thick). Beef slices were formed to make restructured steaks. The steaks were evaluated for cooking characteristics, textural properties and sensory attributes. Restructured steaks made from hot-boned beef were generally considered less tender and received lower texture desirability, flavor desirability and overall palatability ratings as compared to steaks made from aged beef. Restructured steaks made from larger meat slices (5.0 mm) were less tender and received lower texture desirability ratings than restructured steaks made with thinner slices (2.5 mm).     

Sensory, Instrumental Texture Profile and Cooking Properties of Restructured Beef Steaks Made with Various Binders

Restructured steaks made with various binders were evaluated using subjective and objective texture profile analysis of the following treatments: intact ribeye muscle, calcium alginate, salt/tripolyphosphate, crude myosin extract, whey protein, wheat gluten, soy protein isolate, surimi and no additives. Steaks made with calcium alginate or crude myosin extracts had superior binding. Steaks with 1.5% surimi had similar textural properties to those with calcium alginate or crude myosin extract. Whey, wheat gluten or soy isolate protein in restructured steaks detrimentally affected product flavor. Calcium alginate, crude myosin extract and surimi could be potential binders in the manufacture of restructured steaks without deterimental effects on quality.     

Restructured Reindeer Steaks: Effects of Flake Size, Phosphate, and Salt on Sensory Properties

Steaks, fabricated from forequarters from field-slaughtered Alaskan reindeer, were prepared from meat flaked to two sizes (1.295 and 1.905 cm), with (0.5%) and without phosphate, and with (0.5%) and without salt. Phosphate did not appreciably affect sensory properties. Larger flakes and salt improved quality and acceptability, therefore, additional steaks were fabricated from meat flaked with a larger cutting head (4.064-cm) and with three levels of salt (0.0, 0.5 and 0.75%). Steaks containing 0.75% salt were less chewy, softer, juicier, and more acceptable than those made with 0.5% salt but did not differ from those containing no salt. Feasibility of producing restructured steaks from reindeer forequarters was demonstrated.     

Effect of Chloride Salts and Antioxidants on Sensory and Storage Traits of Restructured Beef Steaks

The effects of antioxidants (0.01 or 0.02% of total fat), salt level (0.375 or 0.750%) and salt type (NaCl, KCl or a 65% NaCl + 35% KCl combination) in a 2 × 2 × 3 factorial arrangement on the quality of restructured beef steaks were determined. Meat blends with 0.02% antioxidant had lower thiobarbituric acid (TBA) values than those with 0.01% after 85 to 155 days of frozen storage. Steaks with no salt (pooled across antioxidant levels) had lower TBA values than steaks with any salt type after 85 days storage or either level of salt after 155 days storage. Steaks with either level of added salt resulted in higher ratings for juiciness, saltiness and overall palatability than steaks with no added salt. Juiciness, flavor desirability, saltiness and overall palatability ratings generally were higher for restructured steaks made with NaCl or NaCl + KCl compared to those made with KCl. KCl at 35% of total salt could serve as a NaCl substitute in restructured beef steaks.     

Effects of Pre-rigor Pressurization, Method of Restructuring, and Salt Level on Characteristics of Restructured Beef Steaks

Pre-rigor pressurized beef muscle was processed either by chunking and forming or flaking and forming and then mixed with either 0.00, 0.25 or 0.50% NaCl prior to the manufacture of restructured steaks. To compare the effects of pre-rigor pressurization, a post-rigor, nonpressurized, flaked and formed formulation (containing 0.50% NaCl) was also processed. Data from texture profile panel, Instron and cooking studies were collected. Steaks from pressurized muscle were similar in most characteristics to steaks processed from nonpressurized muscle. Chunking and forming produced a more fibrous, harder and cohesive steak with greater detectable connective tissue than flaking and forming. If pre-rigor pressurized beef is employed in the manufacture of restructured steaks, acceptable texture properties appear obtainable without the use of NaCl.     

Quality Characteristics of Restructured Beef Steaks Manufactured by Various Techniques

Beef (9–11% fat) was restructured with each of six mechanical treatments including chunking, fiberizing, slicing, chunking + slicing, slicing + water, and tenderizing each in combination with addition of 0.5% sodium chloride (salt)/0.5% phosphate, 0.5% Na-alginate/0.5% Ca-lactate, 0.5% Na-pectate/0.5% Ca-lactate, or no additives (control). Beef steaks restructured with salt/phosphate had lower (P<0.05) purge losses: higher binding force and bind scores than control products. Steaks restructured with Na-alginate/Ca-lactate had lower cooking losses and higher bind scores than controls. Use of Na-pectate/Ca-lactate did not improve (P>0.05) purge loss, cooking loss, binding force or sensory properties. Chunked meat or mixtures of chunked and sliced meats in combination with salt/phosphate or Na-alginateica-lactate resulted in steaks with acceptable bind and textural properties.     

Effects of Mechanically Separated Beef with Various Chloride Salts in Restructured Beef Steaks

The effects of various chloride salts (NaCl, MgCl₂, KCl or 65% NaCl + 35% KCl) in combination with mechanically separated beef (MSB at 0, 10 or 20%) on the quality of restructured steaks formulated from bullock chucks were determined. As level of MSB increased, objectionable connective tissue, flavor desirability and overall palatability decreased and off-flavors increased. The development of oxidative rancidity during frozen storage was not affected by MSB level and MSB had little effect on textural traits. NaCl and NaCl + KCl treated steaks received superior flavor and overall palatability ratings over steaks containing MgCl₂ or KCl. Oxidative rancidity developed faster in steaks containing NaCl than the other salt types. Partial replacement (35%) of NaCl with KCl resulted in restructured steaks with sensory properties equal to and storage life superior to steaks with NaCl alone.     

Effect of Phosphate Type and Concentration, Salt Level and Method of Preparation on Binding in Restructured Beef Rolls

The effect of combinations of phosphate type [tetrasodium pyrophosphate (PP), sodium tripolyphosphate (TPP), sodium tetrapolyphosphate (TTPP), and sodium-hexametaphosphate(HMP)], phosohate concentration (0.125%-0.500%). and salt level (0.6%-2.0%) on the binding in restructured beef rolls was studied. The rolls were prepared either with or without a homogenate that contained all the added salts. Preparation method had little effect on binding. The effectiveness of the phosphates was: PP > TPP > TTPP > HMP. Changes in binding produced by varying phosphate type, phosphate concentration and salt level could be explained in terms of changes in ionic strength and pH. Between 90% and 96% of the variation in binding could be explained in terms of these two variables.     

Oxidative Stability of Restructured Beef Steaks Processed with Oleoresin Rosemary, Tertiary Butylhydroquinone, and Sodium Tripolyphosphate

Antioxidant activities were evaluated in raw restructured beef steaks stored at ?20°C six months and in cooked steaks at 4°C six days. During refrigerated storage, thiobarbituric acid-reactive substances (TBARS) and sensory scores indicated sodium tripolyphosphate (STPP) provided (p<0.01) protection against warmed-over flavor development. No significant differences existed between OR (0.10%)/STPP and TBHQ/STPP, due probably to STPP. During frozen storage, a linear concentration effect of OR existed (p<0.01) for both TBARS values and sensory scores indicating OR was an effective antioxidant which combined with STPP produced an additive protective effect during frozen storage. Hexanal content and phospholipid fatty acid profiles also changed during frozen storage. Correlation coefficients between TBARS values and sensory scores were generally nonsignificant.     

Effects of Blade Tenderization and Proteolytic Enzymes on Restructured Steaks from Beef Bullock Chucks

Three studies were conducted to determine the effects of blade tenderization (BT), fungal protease, ficin and papain on sensory ratings, textural properties and frozen storage life of restructured steaks from beef bullock chuck. Neither blade tenderizing of chuck muscles prior to incorporating it into restructured steaks nor the use of 0.05% or 0.10% fungal protease had an effect on the amount of connective tissue or textural properties of the cooked product. The addition of 0.10% fungal protease to restructured steaks increased the frozen storage life of the restructured steaks from 82 days (0%) to 149 days and over 157 days for 0.05%. The addition of ficin and papain had a detrimental effect on texture, flavor and overall satisfaction ratings. The methods tested in the present study are not suitable treatments for reducing the amount of detectable connective tissue in restructured steaks from beef bullock chucks.     

Functional, Sensory, and Microbiological Properties of Restructured Beef and Emu Steaks

Beef and emu steaks were restructured with 5% fibrinogen/0.25% thrombin (F), 0.5% algin/0.5% calcium lactate (A), or 0.5% phosphate/1.5% salt (P). P and A treatments had higher cooked binding strengths and cook yields than the F treatments (P < 0.05). The pH and cook yields of restructured emu were higher than beef (P < 0.05). Binding strength of emu was lower than beef in all binding systems (P < 0.05). F solution had an aerobic plate count (APC) of 39,000/g and increased the microbial count in restructured emu steaks from 940 to 7500/g (P < 0.05). Cooking to 60°C reduced APC to < 250/g (P < 0.05) with progressively greater bacterial kill after cooking to 66°C or 75°C.     

Microbial Characteristics of Three Formulations of Precooked, Vacuum-packaged Restructured Beef Steaks

Restructured steaks were manufactured with hot or cold boned beef using alginate, alginate + dried egg albumin, or salt/phosphate formulations. Raw steaks were sampled for aerobic (26° and 35°C), and gram-negative enteric counts. Cooked vacuum-packaged steaks were sampled for aerobic, gram-negative enteric, lactobacilli and staphylococci and for the presence of Salmonella, Aeromonas, Yersinia, and Listeria during 7 wk storage (2°C). No differences in counts due to formulation were found for raw or cooked steaks. Higher aerobic counts (P<0.10) were observed for raw steaks manufactured from hot-boned sides than from cold-boned sides. Aerobic counts increased (P<0.01) with storage time. Staphylococcus aureus was the only pathogen isolated from cooked steaks.     

Extending Beef Bullock Restructured Steaks with Soy Protein, Wheat Gluten or Mechanically Separated Beef

Nine blends were formulated from young bullocks to contain 0, 10 or 20% mechanically separated beef (MSB), textured soy protein (TSP) or vital wheat gluten (VWG), (Control = no extender). All blends were analyzed for chemical, sensory and visual properties. Control and extended, restructured steaks were not different in juiciness, tenderness or cohesiveness scores or for calcium content. Blends extended with TSP or VWG had a high incidence of off-flavor and all extended, restructured steaks had less desirable visual properties than control blends. Storage life was not affected by type or level of extender. Restructured steaks extended with MSB were not equal to the control, but were superior to TSP or VWG extended steaks.