Composition and physicochemical characteristics of restructured beef steaks containing walnuts as affected by cooking method

The study was conducted to determine the influence of various cooking methods - conventional oven, microwave oven, electric grill and pan-frying on the composition and physicochemical characteristics of restructured beef steaks formulated as low fat (L, 2.0% fat), medium fat (M, 13.0% fat) and 20% added walnut (W, 12.6% fat). Composition, retention coefficients for different compounds, cooking loss (CL) and texture were affected by both formulation and cooking. There was considerable retention of moisture, fat and minerals (as ash) in W samples after cooking. CL was highest (P<0.05) in M sample and lowest (P<0.05) in W samples. Microwaved restructured steaks had higher (P<0.05) kramer shear force (KSF) and bind strength (BS), while pan-fried and conventionally oven-cooked steaks had lower (P<0.05) KSF. The thiobarbituric acid-reactive substances (TBARS) content was low in all restructured steaks but was affected by both cooking and formulation. Although cooking can change the proximal composition of steaks, lipid retention (>90%) was greatest in the case of the W sample, thus assuring that the ultimate objective of these restructured meats, namely to provide a source of walnut and walnut fat, would be successful.     

Physicochemical and sensory characteristics of restructured beef steak with added walnuts

The effects of different proportions (0, 5, 10, 15%) of added walnuts on the physicochemical and sensory characteristics of restructured beef steak were evaluated. The addition of 10 and 15% walnut reduced (P<0.05) cooking loss. Increasing proportions of walnut in the beef steak increased (P<0.05) water binding and reduced (P<0.05) fat binding properties. The addition of walnut did not affect (P>0.05) textural properties in uncooked restructured beef steak, but in cooked products Kramer shear force and bind strength were reduced (P<0.05) when 10% or more of walnut was added. Product morphology characteristics suggest that walnut interferes with the formation of protein network structures. Restructured steaks made with added walnut presented acceptable sensory properties. Incorporation of nuts in meat products can be use to confer potential heart-healthy benefits (Spanish Patent Application 200300367).     

Frozen storage stability of antioxidant-treated raw restructured beef steaks made from mature cows

Previous research has shown that beef quality decreased with the age of cattle. In this study, beef trimmings from nine mature cows (n = 9), equally representing three animal age groups (2–4, 6–8, and 10–12 yr), were restructured into steaks formulated with propyl gallate, alone or in combination with a beefy flavoring agent, to enhance palatability and stability during 6 months of frozen storage at −29 °C. Lipid oxidation, rancidity, and loss of beefy flavor in restructured steaks during extended storage were reduced by propyl gallate. The beefy flavoring agent inclusion masked mature, forage-fed beef off-flavors, intensified beefy flavor, and improved steak tenderness, juiciness and cooking yield. Thus, the combination of propyl gallate and beefy flavoring offers an effective means to enhance the palatability and storage stability of restructured beef prepared from mature cows.     

EFFECT OF SPLEEN IN RESTRUCTURED BEEF

Boneless beef chucks were converted to restructured beef steaks and formulated with 1% NaCl and 0.25% sodium tripolyphosphate (STP). Experimental treatments included (1) control-frozen, (2) control-5 days storage at 0°C, (3) 1% spleen pulp-frozen and (4) 1% spleen pulp-5 days storage at 0°C. Treatments 2 and 4 were evaluated only after storage for 5 days; whereas, treatments 1 and 3 were studied at 5 and 70 days. Spleen pulp enhanced (P<0.05) color development during frozen storage for a short period but offered no (P>0.05) contribution to color preservation during prolonged storage. Visual color and overall appearance were affected more by storage time and conditions than by the addition of spleen pulp. Spleen pulp had no effect (P>0.05) on product cohesiveness, texture, tenderness and flavor of frozen restructured beef steaks but improved the tenderness of unfrozen samples.     

Restructured beef with different proportions of walnut as affected by meat particle size

Microstructure, texture, colour and sensory properties of precooked restructured beef made with different proportions of walnut (0, 5, 10, 15%) were studied in relation to meat particle size (grinder plate hole: 0.6 and 1.4 cm). In general, increasing amounts of walnut were matched by decreasing Kramer shear force (KSF), bind strength and elongation values. When walnut (5 and 15%) was added, products made with coarsely ground meat presented higher KSF values than those made with finely ground meat. Walnut decreased lightness and increased redness and yellowness. Morphology characteristics suggest that walnut interferes with the formation of a gel protein network. Sensory properties were judged acceptable with 5 and 10% of walnut; however, the products scored highest with 10% walnut in finely ground products and 5% walnut in coarsely ground products.     

Nutritional profile of restructured beef steak with added walnuts

Amino acid, fatty acid profile, cholesterol, vitamin E and mineral contents were assessed in restructured beef steak with 20% added walnut (20W). Compared with control restructured beef steak (0% added walnut), the product with added walnut presented a lower (P < 0.05) lysine/arginine ratio, larger (P < 0.05) quantities (mg/100 g product) of monounsaturated (MUFA) and n3 polyunsaturated (PUFA) fatty acids (mainly -linolenic acid), a lower (P < 0.05) n6/n3 PUFA ratio and a higher (P < 0.05) polyunsaturated/saturated fatty acid ratio. The replacement of raw meat material by walnut reduced (P < 0.05) the cholesterol content and increased (more than 400 times) the amount of γ-tocopherol. Iron, calcium, magnesium and manganese contents of 20W sample were greater (P < 0.05) than in the control. Some changes induced by added walnut in the nutritional quality of the restructured product may present health benefits.     

Flavor and Oxidative Stability of Ground Beef Patties as Affected by Source and Storage

Chuck muscles and fat from silage plus grain- and forage-fed steers were stored 7 days at 4°C before patty manufacture or processed into patties and stored at 4°C or ?32°C. The thiobarbituric acid values were constant from 0 to 4 days for frozen patties but decreased (P<0.05) for refrigerated patties. Evaluated by an 11-member trained sensory panel, frozen patties had lower (P<0.05) rancid flavor intensity than refrigerated patties; rancid flavor increased from 0 to 2 or 4 days storage in refrigerated patties. Frozen patties from silage plus grain-fed steers had higher (P<0.05) beefy flavor intensity scores than those from forage beef. However, diet source had no effect (P>0.05) on refrigerated patties.     

Effect of Salt and Phosphate on the Texture and Color Stability of Restructured Beef Steaks

The effect of salt and phosphate on the textural and color properties of restructured beef steaks was investigated. Restructured steaks were manufactured from U.S. Choice beef chucks to contain one of four salt-phosphate levels: 0.0%–0.0% (control); 0.5%–0.0%; 0.0%–0.5%; and 0.2%–0.2%, respectively. Salt and phosphate (0.2% each) decreased cooking loss and increased bind equal to phosphate (0.5%) alone. Phosphate reduced the amount of oxidation. All steaks decreased in redness over the period of frozen storage. The addition of phosphate to restructured beef steaks containing salt enhanced texture with no deterimental effects on color.     

Physicochemical and sensory properties of restructured beef steaks containing beef heart surimi

Summary Restructured beef steaks containing beef heart surimi were prepared. Changes in flavour, texture, thiobarbituric acid-reactive substances (TBARS), and compression force of the restructured steaks were evaluated after frozen storage (−29 °C) for 1, 30, and 90 days. Incorporation of propyl gallate-washed beef heart surimi improved the steak flavour score by 7%, texture score by 30%, and cooking yield by 4%, compared to non-surimi control steaks. Addition of water-washed surimi (without propyl gallate) also improved physical properties of restructured steaks, but it induced off-flavour and rancidity development.     

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.     

Quality characteristics of low-salt restructured poultry with microbial transglutaminase and seaweed

Characteristics of restructured poultry steaks as affected by addition of Sea Spaghetti seaweed (3% dry matter) combined with NaCl reduction and a microbial transgutaminase/caseinate (MTGase/caseinate) system as a cold binding agent were studied during chill storage. The incorporation of Sea Spaghetti caused a slight (P<0.05) increase in purge loss but reduced cooking loss in the products. Addition of MTGase/caseinate did not affect water binding properties. The added seaweed and the MTGase/caseinate system both increased (P<0.05), the Kramer shear force (KSF) of raw products, making them easier to handle. No such effect was observed in cooked products. Products with Sea Spaghetti had higher levels (P<0.05) of total viable counts and lactic acid bacteria, and also higher levels of tyramine and spermidine. All products were judged acceptable by a sensory panel. During chill storage no important changes were found in the target properties due to composition.     

热水协同超高压快速复鲜冷冻牛肉工艺优化

目的:利用热水协同超高压快速复鲜冷冻牛肉,抑制重结晶。方法:以汁液损失率、肉色以及硬度值为指标,通过单因素以及正交优化得出最优复鲜工艺。结果:当采用热水温度40 ℃,压力150 MPa,保压时间40 min时,与常压解冻后的冷冻牛肉相比汁液损失率降低了10%,硬度降低了50%,肉色与新鲜牛肉无显著(p>0.1)色差。结论:按此复鲜工艺解冻复鲜后的牛肉显著(p<0.05)降低了汁液损失率以及肉的硬度,提升了解冻速率,抑制了重结晶,具有广阔的市场前景。     

Influence of Polyphosphate on Storage Stability of Restructured Beef and Pork Nuggets

Influence of polyphosphate on sensory and chemical characteristics of battered and breaded, cooked, restructured beef and pork nuggets was evaluated over 20 wk storage. Beef and pork nuggets manufactured with polyphosphate had lower (P<0.05) initial thiobarbituric acid (TBA) values than those manufactured without polyphosphate (controls); and values remained lower (P<0.05) than control treatments over 20 wk of storage. Sensory panelists detected less (P<0.05) off-flavor in pork nuggets manufactured with polyphosphate than nuggets in control treatments. Detection of off-flavor in pork nugget control treatments may be attributed to higher TBA values (increased lipid oxidation) in the pork product. Addition of polyphosphate protected nuggets from lipid oxidation and subsequent off-flavor development.     

Effect of long frozen storage on the formation of triglyceride alteration compounds of pan-fried functional restructured beef steaks

The influences of pan-frying in extra virgin olive oil (EVO) and frozen storage of functional restructured beef steaks on the contents of polar material (PM) and thermal oxidation compound of the fat extracted from them were determined. Two types of functional restructured meats: 20% walnut-added (W, 13% fat) and low fat (L, 2% fat) were studied in comparison to conventional medium fat (M, 13% fat) restructured beef steaks. Differences in the PM or the thermal oxidation and hydrolytic compounds were mainly due to meat formulation with fried L samples showing the highest PM and polymer concentrations and fried W steaks the lowest. After one year of frozen storage the PM content increased in all samples but markedly in L and W steaks. Polymers decreased in L and increased in W and M steaks. Thermal oxidation compounds increased in W and M steaks while hydrolysis increased markedly in L samples. Long-term storage of all fried steaks is not recommended, whether functional of not since lipid degradation occurs. Although these alterations after one year-frozen storage are still far from their discarding limit, the consumption of just cooked functional steaks is highly recommended.     

Effects of Trimming and Added Connective Tissue on Compositional, Physical and Sensory Properties of Restructured, Pre-cooked Beef Roasts

Restructured beef roasts were prepared using trimmed (intermediate or extensive) and chunked (kidney plate or hand knife) beef shoulder clods with varying levels (0, 10, 20 or 30%) of added connective tissue (flaked with Comitrol^R). Intact beef top rounds (control) and all restructured roasts were water cooked to 62.8°C internal temperature. Increasing connective tissue increased (P<0.05) tenderness and fat of restructured products with no deleterious effect (P>0.05) on product bind. Addition of 30% connective tissue decreased (P<0.05) juiciness and overall acceptability of the products; however, products with addition of 10% or 20% connective tissue were acceptable. Sensory data indicated restructured roasts were as acceptable as intact top rounds.     

Restructured Reindeer Steak Quality as Affected by Antioxidants and Frozen Storage

Restructured steaks were fabricated from forequarter muscles from field-slaughtered Alaskan reindeer. Steaks were formulated with an antioxidant (1:1 mixture of BHA and TBHQ with a propylene glycol carrier) at 0.00, 0.01 and 0.02% of the fat and 0.5% salt. Steaks were flash-frozen, vacuum-packaged and stored at ?18°C. Instrumental and sensory testing was conducted after storage (2, 6, 10, 14, 18, 22 wk). Minimal effects occurred on moistness, greasiness, softness and chewiness. Gamy flavor intensity decreased and off-flavor intensity fluctuated with storage and antioxidant. Effects of antioxidants on color were not notable. Use of the antioxidant system is not justified by any oxidative or color effects. Frozen storage was not detrimental to restructured steak quality.     

洋葱汁添加量及滚揉时间对预制牛排品质和贮藏稳定性的影响

为改善传统牛排煎制后汁液流失、肉质干硬、咀嚼性差的现状,本文首先通过对牛排蒸煮损失、色差、质构以及感官评价等指标的测定,来筛选洋葱汁预制牛排中洋葱汁的添加量(0、3%、6%、9%、12%、15%),然后对最佳洋葱汁添加量下预制牛排的滚揉时间(0、5、10、15、20、25 min)进行优化,最后对洋葱汁预制牛排的贮藏稳定性进行分析。结果表明,洋葱汁的添加和滚揉操作的进行均对牛排的食用品质有显著影响(p<0.05)。随着洋葱汁添加量的增加以及滚揉时间的延长,牛排的蒸煮损失、硬度和咀嚼性均呈现先下降后上升趋势,感官评分总体可接受性与之完全相反,先上升后下降。当洋葱汁添加量为9%,滚揉时间为10 min时,调理牛排的蒸煮损失达到最小值,分别为13%和14.33%;弹性达到最大值,分别为0.95、0.94 mm;此时牛排的口感以及总体可接受性评分最佳(p<0.05)。此外,添加了洋葱汁的牛排硫代巴比妥酸值(thiobarbituric acid values,TBARS)和过氧化值(peroxide values,POV)都有明显下降(p<0.05)。综合蒸煮损失、色差、质构和感官评分的结果,选择调理牛排的洋葱汁最佳添加量为9%,最佳滚揉时间为10 min。本研究结果为牛排规模化生产提供有效参考。     

RESTRUCTURED BEEF AND TURKEY STEAKS

Raw Materials from U.S. Choice beef chucks boned 24 h postmortem and frozen boneless turkey thighs stored approximately 120 h were flaked and incorporated in four restructured formulations with each containing 1.0% NaCl and 0.25% sodium tripolyphosphate (STP). Formulations included beef (B), beef plus 0.5% sugar (BS), 50% turkey (BT) and 50% beef and 50% turkey plus 0.5% sugar (BTS). At 0, 21 and 84 day, subjective evaluations were conducted for discoloration, cohesiveness, muscle cut resemblance and overall appearance. Objective measurements included Hunter Color and TBA values. Overall appearance and discoloration (measured visually and objectively) were affected more by storage time than by raw materials and flavor adjuncts. The effect of raw materials and sugar on the sensory attributes was minimal except that the formulations containing turkey had higher TBA values.     

Impact of Added Encapsulated Phosphate Level on Lipid Oxidation Inhibition during the Storage of Cooked Ground Meat

The effect of levels (0.1%, 0.2%, 0.3%, 0.4%, 0.5%) of added encapsulated (e) phosphate (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation inhibition during storage (0, 1, and 7 d) of ground meat (chicken, beef) was evaluated. The use of eSTP and eSPP resulted in lower and higher cooking loss (CL) compared to eHMP, respectively (P < 0.05). Increasing encapsulated phosphate level (PL) enhanced the impact of phosphates on CL in both chicken and beef samples (P < 0.05). Encapsulated STP increased pH, whereas eSPP decreased pH (P < 0.05). pH was not affected by PL. The highest orthophosphate (OP) was obtained with eSTP, followed by eSPP and eHMP (P < 0.05). The level of OP determined in both chicken and beef samples increased (P < 0.05) during storage. Increasing PL caused an increase in OP (P < 0.05). The highest reduction rate in the formation of thiobarbituric acid reactive substances (TBARS) and LPO for both meat species were obtained with eSPP, followed by eSTP and eHMP (P < 0.05). Increasing PL resulted in lower TBARS and LPO (P < 0.05). Findings suggest that encapsulated phosphates can be a strategy to inhibit lipid oxidation for the meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by increasing PL.     

Frozen storage stability of vacuum-packaged precooked restructured steaks manufactured from mature cow beef

Beef trimmings from nine cows, equally representing three animal age groups (2-4, 6-8, and 10-12 year), were restructured into steaks formulated with propyl gallate, alone or in combination with a beefy flavoring agent, to enhance palatability and storage stability. Steaks were fully cooked prior to being stored under vacuum for 6 months at −29 °C. Animal age did not affect steak quality and lipid stability, whereas sensory palatability scores and reheating yield decreased significantly beyond 3 months. Propyl gallate did not impart any additional protection against lipid oxidation beyond that provided by vacuum packaging. On the other hand, inclusion of beefy flavoring agent masked all mature, forage-fed beef off-flavors, intensified beefy flavor and improved steak tenderness, juiciness and reheating yield. The incorporation of a beefy flavoring agent was shown to be an effective means to enhance the palatability of vacuum packaged precooked steaks manufactured from mature cows.