Changes in Tenderness, Color, and Water Holding Capacity of Broiler Breast Meat during Postdeboning Aging

ABSTRACT:  The impact of postharvest aging on the tenderness, color, water holding capacity, and appearance of broiler breast fillets after deboning was investigated. A total of 360 broilers were processed and deboned at either 1.5-, 3-, or 6-h postmortem (PM) and aged at 4 ± 1 °C for up to 6 d. Tenderness was predicted by the Meullenet–Owens razor shear. Drip loss, cook loss, color, and muscle-shape profiles were also evaluated during the 6-d aging duration. Deboned fillets were in the tenderness range corresponding to "neither tough nor tender" for the first 2 d of aging and changed into "slightly tender" after 3 d of aging according to the instrument-tenderness perception equivalent scale. Tenderization due to postdeboning aging seemed to be more pronounced for fillets deboned in a prerigor state (that is, 1.5- and 3-h PM). Over the aging period, tenderness improved by 6.9 and 7.4 percentage points for the 1.5- and 3-h PM treatments, respectively, while those fillets deboned in a postrigor state (6-h PM) exhibited no significant difference in tenderness. Drip and cook loss of fillets consistently increased over the aging period. The color of fillets tended to become less red and more yellow during aging although there was no significant difference in  L *. Overall, the tenderizing effects of deboned broiler breast fillets during the storage of 6 d were minimal but seemed to be affected by fillet height and length as determined through analysis of covariance (ANCOVA) and K-means clustering analysis. Thicker and tougher fillets were more susceptible to the tenderizing effects during postdeboning aging.     

Combined effect of electrical stimulation, aging time and marination on quality of chicken breast fillet processed under commercial conditions

BACKGROUND: Electrical stimulation (ES) in poultry processing is reported in the literature with varying degrees of effectiveness. Furthermore, the combined effects of ES and polyphosphate marination are not completely known. The objective of this study was to evaluate the combined effect of ES, aging time prior to deboning and phosphate marination on meat quality of broiler breast fillets. RESULTS: The implementation of ES accelerated pH decline in fillets at any aging time studied regardless of marination treatment, but no differences (P > 0.05) were found in pH of fillets deboned without aging. Warner–Bratzler (WB) shear values of ES fillets significantly decreased (P < 0.05) at 2 h of aging whereas WB of non‐ES fillets decreased at 6 h of aging in breast meat, with or without marination. In non‐marinated fillets the ES treatment reduced (P < 0.05) cooking loss in meat aged 0, 2 and 4 h. In marinated fillets the ES treatment decreased cooking loss at 2, 4, 6 and 8 h of aging. CONCLUSION: ES in carcasses aged 2 or 4 h improves tenderness and reduces cooking loss. Marination improves tenderness in both stimulated and non‐stimulated fillets, at all aging times. Copyright © 2012 Society of Chemical Industry     

Raw-meat packaging and storage affect the color and odor of irradiated broiler breast fillets after cooking

Raw breast fillets were divided into two groups and either vacuum or aerobically packaged. The fillets in each group were subdivided equally into two groups and then irradiated at 0 or 3 kGy using a Linear Accelerator. After 0, 3 and 7 days of storage at 4?°C, fillets were cooked in an 85?°C water bath (cook-in-bag) to an internal temperature of 74?°C. Oxidation-reduction potential (ORP) of raw fillets was measured before cooking, and color and sensory characteristics were analyzed after cooking. Irradiation decreased the ORP of meat, but the potential in aerobically packaged fillets increased during storage. After cooking, color a*-value of irradiated fillets was higher than that of the non-irradiated. Irradiation of raw meat also changed color L* and b* values after cooking. Aerobic storage reduced the redness of cooked meat induced by irradiation. Irradiated raw broiler fillets stored for 0 day and 3 day under aerobic conditions before cooking produced a oxidized chicken-like odor. The odor, however, disappeared after 7 days of storage under aerobic conditions before cooking. For raw broiler samples stored under vacuum conditions, significant differences in color and odor between irradiated and non-irradiated fillets remained throughout the 7-day storage period after cooking. Irradiation had only a minor influence on lipid oxidation of raw breast fillets as indicated by low TBARS values. This study indicates that the effect of irradiation on color and odor of broiler breast fillets after cooking can be reduced significantly through shelf-display of raw fillets under aerobic conditions. Storage under vacuum conditions before cooking is not effective in reducing irradiation-induced changes in the color and odor of breast fillet after cooking.     

液氮/液氨速冻鮰鱼片理化性质与组织结构变化

研究分析液氮与液氨速冻对斑点叉尾鮰鱼肉品质的影响。新鲜斑点叉尾鮰分割鱼片后分别进行工业隧道式液氮喷淋速冻（－90 ℃、35 min）、隧道式液氨速冻（－35 ℃、90 min）,速冻样品置于－18 ℃下贮藏90 d。分析比较新鲜鱼肉以及速冻鱼肉在不同冻藏时间解冻损失率、蒸煮损失率、加压失水率、剪切力、pH值、K值、挥发性盐基氮（total volatile basic nitrogen,TVB-N）含量、三甲胺（trimethylamine,TMA）含量与硫代巴比妥酸反应物（thiobarbituric acid reactive substance,TBARs）值,应用荧光显微镜观察鱼肉组织微观结构变化。结果表明：与新鲜鱼肉相比,速冻鱼肉蒸煮损失率增加,加压失水率、剪切力、pH值降低,K值、TVB-N含量、TMA含量、TBARs值均呈上升趋势;随着冻藏时间延长,速冻鱼肉理化性质发生劣变;鱼肉速冻后肌肉细胞面积减小,细胞间隙增大;相比液氨速冻,液氮速冻更有利于保持鱼肉持水性、新鲜度以及组织结构完整性,可有效抑制鱼肉冻藏期间的品质劣变。综上,液氮速冻可以有效保持冷冻鱼肉品质,冻藏30 d内,液氮速冻鱼肉品质特性更接近于新鲜鱼肉。     

EVALUATION OF DUCKLING BREAST MEAT SUBJECTED TO DIFFERENT METHODS OF FURTHER PROCESSING AND COOKING

Breast fillets (128 total) deboned from commercially processed 7-week-old Pekin ducklings were subjected to one of four tenderization treatments: control, mechanically tenderized, marinated, or tenderized and marinated, and one of two cooking methods, oven-baked or gourmet-cooked. Treatments were evaluated for cooked yield and tenderness. Mechanical tenderization resulted in the lowest cooked yield, 60.0%, followed by the control, 64.5%. Mechanical tenderization and the control treatment were not significantly different for shear, with an average of 7.0 kg shear/g sample. Marination, with or without mechanical tenderization, resulted in signficantly greater cooked yield, 72.6 and 72.9 % respectively, and more tender meat, 4.9 and 5.1 kg shear/g meat respectively. Oven baking resulted in a signficantly greater cooked yield than gourmet cooking. Results indicate that marination, with or without mechanical tenderization, can significantly improve the cooked yield and tenderness of duckling breast fillets.     

Cryoprotectants Affect Physical Properties of Restructured Trout During Frozen Storage

ABSTRACT: Cryoprotectants other than sucrose/sorbitol were evaluated to reduce the sweetness of restructured trout products during frozen storage. Bacterial growth, lipid oxidation, thaw loss, cook yield, color, and texture were evaluated after 1 d, 3 mo, and 6 mo of storage at-20 °C. Sucrose/sorbitol, trehalose, andtrehalose/sorbitol at 8% equally exhibited a cryoprotective action and minimized thaw loss and texture changes, whereas sodium lactate did not at 2% during 6 mo of frozen storage. Raw, carbohydrate-treated products had less L * values than the control and sodium lactate products. After cooking, no difference in L * value was observed. Cryoprotectants and frozen storage time did not affect bacterial growth and lipid oxidation of raw products.     

预冷处理对冻罗非鱼片品质的影响

拟在现有冻罗非鱼片工艺中加入预冷工序。将新鲜罗非鱼片用冰水浸渍,放入不同温度(-4、-7、-18℃)条件下冻藏,定期测定pH值、色差、失水率、挥发性盐基氮(total volatile base nitrogen,TVB-N)值和质构等参数,分析预冷对冻藏品质的影响。结果显示,预冷对p H值影响最显著的温度为-7℃,10~20 d时-7℃预冷处理组罗非鱼片p H值仍在继续下降,而其对照组已开始回升。随着贮藏时间延长,罗非鱼片色差亮度L*值与红度值a*均呈现下降趋势,且贮藏温度越低,下降幅度越小,同时发现对照组L*值和a*值普遍低于预冷处理组。同时,贮藏温度越低,失水率越高,30 d罗非鱼片失水率达到最高值,-18、-7℃对照组此时失水率达7.47%、6.82%。-4℃及-7℃预冷处理对罗非鱼片TVB-N值影响较大,20 d后与对照渐趋一致;但30 d时-18℃罗非鱼片预冷处理组与对照组仍有较大差别,TVB-N值分别为8.04 mg/100 g和9.87 mg/100 g。20 d前随贮藏温度降低罗非鱼片预冷处理组与对照组的咀嚼性差异增大,之后则趋于一致。贮藏期间硬度无显著差异,弹性仅在-4℃内罗非鱼片处理组与对照组间有较明显差异,其余差异均不显著(P0.05)。内聚性的变化因无明显规律不作为评判指标。综上,预冷处理对罗非鱼冻鱼片部分冻藏品质指标有较明显的改善作用,利于保持鱼片品质,可作为生产企业的借鉴。     

Comparison of Variable-Blade to Allo-Kramer Shear Method in Assessing Rainbow Trout (Oncorhynchus mykiss) Fillet Firmness

Abstract: A variable‐blade (VB) attachment was compared to the Allo‐Kramer (AK) shear attachment for texture analysis of rainbow trout fillets from 2 experiments; effects of attachment configuration, storage regimen, and cooking temperature are evaluated. In the 1st experiment, AK detected differences in force measurement, and VB showed that the perpendicular orientation yielded the highest response (P < 0.05). Fillets refrigerated (4 °C) for 0 d were firmer than fillets stored for 14 d (337.36 compared with 275.90 g/g). Raw fillets were firmer than cooked fillet (333.79 compared with 279.46 g/g). In the 2nd experiment, frozen storage at –25 °C for 30 d after refrigerated storage (R3F30 and R7F30) decreased VB shear force (P= 0.0019) and AK energy of shear (P= 0.0001) by 1.5‐ and 2‐fold compared to those evaluated after refrigerated storage for 3 and 7 d (R3 and R7), respectively. Cooking increased VB and AK texture for all storage regimens (P < 0.05). In both studies, instrumental texture did not correlate with alkaline‐insoluble hydroxyproline (P > 0.05). Shear direction affected force generated by the VB attachment, and this attachment could discriminate shear force differences due to cooking and frozen‐storage. Practical Application: Fillet texture was determined by a recently developed device and compared to texture determined by the Allo‐Kramer shear attachment; both responses were related to collagen content. The VB attachment defined fillet texture as affected by cooking and storage condition.     

Phosphate Type Affects the Quality of Injected Catfish Fillets

ABSTRACT:  Catfish fillets were injected to 115% over green weight prior to tray-packing and storage at 4 °C for 1, 4, 8, and 11 d. Fillets were evaluated for yields, surface color, pH, cooking loss, tenderness, purge loss, and shelf-life. All phosphate treatments increased ( P  < 0.05) fillet tenderness, but the agglomerated blend of sodium phosphates (AGSP) increased ( P  < 0.05) pH and yields, and decreased ( P  < 0.05) CIE  L * and CIE  b * values. Psychrotrophic plate counts (PPC) of fillets treated with the agglomerated blend of polyphosphates (AGPP) were lower ( P  < 0.05) than the control at each storage time, but PPC of all samples reached 7 log CFU/g by day 8 of storage. All agglomerated phosphates and STP (sodium tripolyphosphate) improved yields and quality when compared to the nonmarinated control. However, AGSP was the most effective phosphate at increasing pick-up and yields and decreasing cooking loss due to the pH effect that causes more water to be trapped within the food system. Major quality differences may not have occurred between STP and agglomerated phosphates (other than AGSP) since injection relies solely on pH and ionic strength for marinade pickup, whereas tumbling also relies on mechanical action, which relies more on the presence of various phosphate chain lengths and solubility to impact yields. All phosphate treatments improved the quality of tray-packed, refrigerated catfish fillets that were enhanced through multineedle injection. However, AGSP also increased fillet pH, optimized yields, and improved color.
Practical Application: Use of an agglomerated phosphate blend with a high pH (AGSP) maximized the yield of catfish fillets that were marinated through multineedle injection. In addition, STP and agglomerated phosphate blends increased the yield and tenderness of catfish fillets when compared to the nonmarinated control.     

低盐腌制对乌鳢冷藏过程中品质变化的影响

本文以乌鳢(Ophicephalus argus)为研究对象,研究了冷藏(4±1) ℃条件下分别以0.5%、1.0%、1.5%的食盐腌制对乌鳢鱼肉品质变化规律的影响,通过感官评分、pH、色泽、嫩度、蒸煮损失、汁液损失、盐溶蛋白、硫代巴比妥酸值(TBARS)、挥发性盐基氮(TVB-N)等指标,探究了不同浓度食盐对生鲜及腌制鱼肉贮藏品质的影响。结果表明:随贮藏时间的延长感官分值逐渐降低,对照组(0%食盐组)于第8 d就已失去食用价值,而T₃组(1.5%食盐组)在第12 d时仍可食用。在贮藏过程中,盐溶蛋白呈下降趋势;pH呈现波动性变化;蒸煮损失总体呈下降趋势。此外,TBARS值、汁液损失率、挥发性盐基氮含量在贮藏期间呈增长趋势。研究表明,T₃组(1.5%食盐组)在一定程度上减缓冷藏过程中乌鳢鱼片的品质变化,但会降低肌肉保水性、促进脂肪的氧化。     

不同冻结速率对鸡胸肉品质的影响

为研究冻结速率对鸡胸肉品质的影响,将24只三黄鸡屠宰并预冷8 h后取胸肉作为研究对象,样品分为3个处理组,分别置于-15、-25、-35℃下冻结,测定冻结速率、解冻汁液流失率、加压失液率、蒸煮损失率、色差、蛋白质溶解度、TBARS值、Ca2+-ATPase活力的变化。结果表明:冻结速率对鸡胸肉解冻汁液流失率、加压失液率、蒸煮损失率、色差、TBARS值、Ca2+-ATPase活力有显著影响(P<0.05),而对蛋白质溶解度无显著影响(P>0.05),且冻结速率越大,鸡胸肉品质越好。     

紫苏水提物联合蒸煮处理对脆肉鲩鱼片冻藏过程中品质的影响

为了研究蒸煮处理及紫苏水提物对脆肉鲩鱼片冻藏品质的影响,以紫苏水提物浸泡的生鱼片（生鱼片组）、紫苏水提物浸泡再进行蒸煮制备的熟鱼片（熟鱼片组）、蒸馏水浸泡的生鱼片（对照组）为研究对象,研究这3 组鱼片在冻藏过程中质构、持水性、盐溶性蛋白含量、Ca2＋-ATPase活性、硫代巴比妥酸（thiobarbituric acid,TBA）值、挥发性盐基氮（total volatile base-nitrogen,TVB-N）含量和感官评分的变化。结果表明：熟鱼片及生鱼片组通过最大冰晶生成带的时间比对照组长;与对照组和生鱼片相比,熟鱼片在冻藏过程中一直维持较高的硬度、弹性、咀嚼性、TBA值和较低的持水力、盐溶性蛋白含量、TVB-N含量;与对照组相比,生鱼片组的质构特性、持水力、盐溶性蛋白含量和Ca2＋-ATPase活力更高,而TBA值和TVB-N含量更低,冻藏300 d后,生鱼片TBA值是贮藏初始时的3.85 倍,TVB-N含量低于20 mg/100 g;感官评价结果进一步表明,3 组样品感官品质在冻藏过程中不断下降,其质地、口感以及汤汁浑浊度评分从高到低依次是熟鱼片、生鱼片和对照组。研究结果证明了紫苏水提物联合蒸煮处理更有利于冻藏过程中脆肉鲩鱼片品质的维持。     

Validation of a Combi Oven Cooking Method for Preparation of Chicken Breast Meat for Quality Assessment

ABSTRACT: Quality assessment results of cooked meat can be significantly affected by sample preparation with different cooking techniques. A combi oven is a relatively new cooking technique in the U.S. market. However, there was a lack of published data about its effect on quality measurements of chicken meat. Broiler breast fillets deboned at 24‐h postmortem were cooked with one of the 3 methods to the core temperature of 80 °C. Cooking methods were evaluated based on cooking operation requirements, sensory profiles, Warner–Bratzler (WB) shear and cooking loss. Our results show that the average cooking time for the combi oven was 17 min compared with 31 min for the commercial oven method and 16 min for the hot water method. The combi oven did not result in a significant difference in the WB shear force values, although the cooking loss of the combi oven samples was significantly lower than the commercial oven and hot water samples. Sensory profiles of the combi oven samples did not significantly differ from those of the commercial oven and hot water samples. These results demonstrate that combi oven cooking did not significantly affect sensory profiles and WB shear force measurements of chicken breast muscle compared to the other 2 cooking methods. The combi oven method appears to be an acceptable alternative for preparing chicken breast fillets in a quality assessment.     

不同温度冻藏对军曹鱼片品质的影响

研究不同冻藏温度(－ 10、－ 18、－ 30℃)对军曹鱼片部分理化指标、质构特性及感官品质的影响。结果表明,冻藏温度对军曹鱼片的解冻汁液流失率、蒸煮损失率、盐溶蛋白含量、Ca2+-ATPase 活性和TBA 值(硫代巴比妥酸)均有显著性影响(P ＜ 0.05)。冻藏时间越长、冻藏温度越高,汁液流失率、蒸煮损失率、TBA 值增加越大,盐溶蛋白含量、Ca2+-ATPase 活性下降也越多,即保水性降低、蛋白质变性程度增大、脂肪氧化加快。TPA(质构分析)发现军曹鱼片的硬度和耐嚼性随着冻藏时间的延长均呈显著增加趋势(P ＜ 0.05),而回复性则显著下降(P ＜ 0.05);冻藏温度越低,相应的硬度和耐嚼性就越小,而回复性则越大。感官评价表明冻藏导致军曹鱼片的品质下降,冻藏温度越高,品质劣变就越严重。采用较低的温度(－ 30℃)冻藏可以最大限度的保持军曹鱼片的品质。     

不同冻藏条件对鸡胸肉品质特性的影响

为研究不同冻藏条件对鸡胸肉品质特性的影响,本实验以新鲜鸡胸肉为原料,于-16、-26和-36 ℃分别冻藏1、2、3、4、5、6个月,分析比较不同冻藏温度和时间对鸡胸肉的系水力、色泽、蛋白质变性程度、嫩度、脂肪酸败及新鲜度的影响情况。结果表明,随着冻藏温度的升高及冻藏时间的延长,pH呈现先降低后升高的趋势,鸡胸肉的解冻损失率、蒸煮损失率、剪切力以及b*值也逐渐增加,L*值、总蛋白及肌原纤维蛋白溶解度显著降低(p<0.05),但对肌浆蛋白的溶解度无显著影响(p<0.05);a*值则在冻藏前1个月显著增加(p<0.05),但随后逐渐降低,且随着冻藏温度升高而减小(p<0.05)。衡量系水力指标的解冻损失和蒸煮损失结果,衡量色差的L*、a*和b*值以及衡量蛋白变性指标的三大蛋白溶解度和TBARS值与TVB-N值均表明,鸡胸肉在冻藏温度为-36~-26 ℃及冻藏时间为5个月内能有效维持较好的鸡胸肉食用品质。此外,各指标间的相关性分析表明,不同冻藏条件下解冻损失率、蒸煮损失率、剪切力、TVB-N值、TBARS值、a*值、b*值、蛋白溶解度与新鲜鸡胸肉呈现显著的差异(p<0.05),而pH、L*值与新鲜鸡胸肉差异不明显(p>0.05)。本文为快速发展的冷冻禽肉的加工及贮藏环境提供了理论依据。     

Effect of pH and prefreezing treatment on the texture of yellowtail rockfish (Sebastes flavidus) as measured by the Ottawa Texture Measuring System

Texture is very important to the organoleptic quality of fish products. Poor frozen storage conditions or improper prefreezing treatment can result in unacceptably tough fillets. With some species, undesirable soft, mushy texture develops during chill storage.
This study is concerned with the influence of treatment prior to freezing (samples were frozen pre-rigor, in-rigor, post-rigor and after 6 days' chill storage in ice or refrigerated sea water) on the texture of yellowtail rockfish stored frozen as whole gutted fish or as fillets. The effect of pH was also studied. Texture was measured objectively using the Ottawa Texture Measuring System on samples stored for 6 months at −28°C.
A very good negative correlation was found between pH level and toughness as measured using a Kramer shear-compression cell in the Ottawa Texture Measuring System. Fish stored in refrigerated sea water prior to freezing were appreciably more tender. There was no statistical difference in texture (shear press force) values between samples stored as whole fish versus samples stored as fillets.     

Relating instrumental texture, determined by variable-blade and Allo-Kramer shear attachments, to sensory analysis of rainbow trout, Oncorhynchus mykiss, fillets

Texture is one of the most important quality attributes of fish fillets, and accurate assessment of variation in this attribute, as affected by storage and handling, is critical in providing consistent quality product. Trout fillets received 4 treatments: 3-d refrigeration (R3), 7-d refrigeration (R7), 3-d refrigeration followed by 30-d frozen storage (R3F30), and 7-d refrigeration followed by 30-d frozen storage (R7F30). Instrumental texture of raw and cooked fillets was determined by 3 approaches: 5-blade Allo-Kramer (AK) and variable-blade (VB) attachment with 12 blades arranged in perpendicular (PER) and parallel (PAR) orientations to muscle fibers. Correlation between instrumental texture and sensory hardness, juiciness, elasticity, fatness, and coarseness was determined. Muscle pH remained constant at 6.54 to 6.64. Raw fillets lost 3.66% of their original weight after 30-d frozen storage. After cooking, weight loss further increased to 15.97%. Moisture content decreased from 69.11 to 65.02%, while fat content remained constant at 10.41%. VBPER detected differences in muscle sample strength (P= 0.0019) and demonstrated effect of shear direction reported as maximum force (g force/g sample). AKPER detected differences in energy of shear (g × mm; P= 0.0001). Fillets that received F30 treatments were less extensible. Cooking increased muscle strength and toughness. Force determined by VBPER was correlated with sensory hardness (r= 0.423, P= 0.0394) and cook loss (r= 0.412, P= 0.0450). VB attachment is accurate, valid, and less destructive in fillet texture analysis. PRACTICAL APPLICATION: A new shearing device was validated with sensory analysis. Settings and parameters obtained could be used to define fillet texture quality associated with muscle fiber orientation.     

FREEZING OF RAW BEEF: INFLUENCE OF AGING, FREEZING RATE AND COOKING METHOD ON QUALITY AND YIELD

The combined effects of aging, freezing rate, frozen storage and cooking method on beef quality and yield were studied in a multifactorial experiment, using 1.5 cm slices of LD muscles from young steers. Aging for 2 wk resulted in significantly more tender, but slightly less juicy frozen meat than aging for 4 days. Prolonged frozen storage gave tougher meat and a larger tenderness difference between aging times. Freezing rates of 13, 2.0 and 0.04 cm/h differed but little in their effect on sensory quality, but slightly lower yield and redness value were noted for the lowest rate. Pan frying directly from the frozen state resulted in slightly higher juiciness and cooking yield, with larger differences in yield between freezing rates, than cooking after previous thawing. Significant interactions were noted for cooking method × freezing rate and for aging time × frozen storage time