Effects of Heating System, Temperature and Rate of Heating on Sensory Characteristics of Beef

Sensory scores for appearance and texture of oven-roasted beef semitendinosus were compared with those of samples heated in glass tubes in a water bath. Roasts heated in 93 and 149°C ovens appeared to be less done and were moister than water bath samples heated at comparable rates. Samples heated to 60°C in both systems appeared to be less done and were moister and less mealy than samples heated to 70°C. Few differences in sensory scores for textural parameters were attributed to heating system, endpoint or heating rate. Correlations between scores for intact roasts and objective measurements for the small samples were not always of the same direction or strength as were the relationships between scores and objective values for roast samples.     

Marinade pH Affects Textural Properties of Beef

Marinades of different pH were prepared from 0.1M phosphate buffers ranging in pH from 3.25 to 10.15, 0.1M sodium chloride, 0.4M phosphoric acid or 0.7M acetic acid. Beef cores were marinated and composition, texture, and structural properties were evaluated. Low and high muscle pH after marinating had positive effects on texture and resulted in increased water-binding capacity, moisture content and decreased cooking losses. Electron microscopy indicated a loss of the M-line at low pH and a loss of Z-line material at high pH. Overall, both high and low marinade pH altered the textural properties of meat although, more rapid changes occurred at lower pH.     

无硝配方及受热差异对牛肉粒作用效果的研究

肉类的无硝或低硝腌制方法是值得探索的课题。本研究以牛肉为试材,采用红曲色素、VC、EDTA二钠、柠檬酸、乙基麦芽酚等添加剂,进行了无硝、低硝腌制系统的研究。在发色、保鲜等特性方面,各样品与亚硝酸盐常规用量(156×10-6)的对照比较,结果显示:采用的无硝和低硝的腌制剂对牛肉的腌制效果,在色度、新鲜度方面可达到和优于对照所能达到的指标,且无硝腌制剂样品中亚硝酸盐残留量显著的低于对照,而采用低硝(30×10-6)腌制剂的样品亚硝酸盐残留量与对照无显著差异。另外,因腌制后热处理的程度差异,导致了肌红蛋白的不同的变性程度,影响了腌制剂的发色等效用,因此,应根据产品制作时的受热参数的不同进行腌制剂的配比。     

Effect of Inorganic Polyphosphates on Ground Beef Characteristics: Microbiological Effects on Frozen Beef Patties

Microbiological effects of 0.4% sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP), and three commercial phosphate blends were studied in frozen (90 days, ?20°C) and subsequently temperature-abused (24–25°C, 24 hr) beef patties. Phosphates did not significantly (p>0.05) reduce mesophilic, psychrotrophic, presumptive 5. aureus and lactic acid bacterial numbers during frozen storage of the patties, but one of the commercial blends and TSPP inhibited bacterial growth upon subsequent elevated-temperature abuse. However, bacterial inhibition by phosphates during temperature abuse was not sufficient to prevent spoilage of the patties.     

Effects of Flake Size on Textural and Cooking Properties of Restructured Beef and Pork Steaks

Flaked and formed beef and pork steaks were manufactured using eleven different Comitrol cutting heads selected to give a wide range in flake size. Data from texture profile panel, Instron and cooking studies were collected. As flake size increased, visually detected fi-brousness, first bite hardness, cohesiveness of the chewed mass, number of chews required for swallowing, amount of connective tissue detected by sensory panel and shear force all increased, while uniformity of the chewed mass decreased. Textural properties in beef and pork steaks were affected in a similar manner by flake size. Thickness of the flake particle was as important as width of the flake particle in affecting texture.     

从力学性质测试与感官鉴定分析加热方式对马铃薯组织结构的影响

马铃薯片分别以沸水、蒸汽和微波三种方式加热一段时间后,测其中心温度,并经力学性质测试和感官鉴定两种方法对其组织结构变化进行评价。实验发现不论哪种加热方式,两种评价结果都存在着相互对应的关系;薯片组织结构变化的程度,并不完全取决于加热后食品中心达到的温度,而主要与加热方式和加热速率有关。     

Qualitative and Quantitative Textural Assessment of Cooked Ground Beef Patties

Cohesiveness of extruded, sliced hamburger patties from two manufacturers was studied in relation to cooking performance. Tensile determinations of ultimate strength and toughness were related to cohesiveness as measured with an Instron Universal Testing Machine. Light and environmental scanning electron microscopy was used to relate physical and macroscopic observations. Very cohesive samples had values of ultimate strength 7>1.45N and toughness >3.70 × 10^?4J, and noncohesive samples had values of ultimate strength <0.90N and toughness <1.50 × 10^?4J. Tensile results allowed discrimination between levels of cohesiveness among ground beef patties and could serve as a monitoring device to ensure consistency and indicate failure of the product at the serving outlet.     

Dynamical Changes of Beef Intramuscular Connective Tissue and Muscle Fiber during Heating and their Effects on Beef Shear Force

Changes of meat shear force and its characteristics during cooking have been extensively studied, but great variability existed due to the cooking method among different studies. This study was designed to focus on the dynamic changes of beef intramuscular connective tissue (IMCT) and muscle fiber during water-bath heating and their effects on beef shear force. At 4 d postmortem, beef semitendinosus muscles were divided into 11 steaks and then cooked respectively to an internal temperature of 40, 50, 55, 60, 65, 70, 75, 80, 85, and 90°C (the remainder was not cooked as control). Collagen content and its solubility, transition temperature of perimysia and endomysia, fiber diameter, and Warner–Bratzler shear force values (WBSF) were determined. The results showed that fiber diameter decreased gradually during cooking, concomitant with the increases in filtering residue and WBSF. The maximum transition temperature (T _max) of endomysial components was lower than that of perimysial components (50.2 vs. 65.2°C). Muscle fiber and IMCT (especially perimysia) shrank during cooking, resulting in the increase of WBSF when the internal temperature was lower than 75°C, but further cooking led to the disintegration of perimysial structure, lowing up the increase of WBSF between 75 and 90°C. For beef semitendinosus muscle, the internal temperature of 65°C is a critical cooking point where meat gets tougher.     

Textural and Chemical Characteristics of Recombined Precooked Beef Chuck Roasts as Influenced by Boning Time and Salt Level

The effects of hot-boning (HB) and salt level (SL) (0, 0.5, 1.0%) on recombined precooked roasts from three beef chuck recombined whole muscles were investigated using a system that employed electrical stimulation, blade tenderization, vacuum massage and the addition of phosphate. SL and muscle type (MT) significantly affected proximate composition (protein, fat and moisture). Maximum yields were obtained with hot-boned treatments at the highest salt level. Instron measurements were affected by MT, HB and SL. Results of this study indicate that binding of large meat pieces together to form low calorie recombined, precooked roasts can be achieved.     

Processing Ingredients Affecting Oxidative and Textural Stability of Restructured Beef Roasts

Restructured beef roasts containing 0.3% sodium tripolyphosphate (STP) and 1% soy protein isolate (SPI); or STP only; or SPI only; or no STP or SPI were cooked at 70 or 100°C to an internal temperature of 65°C, then stored at 4°C for 0 and 3 days. In control roasts, the higher cooking temperature resulted in higher (p ≤ 0.05) TBA values. STP and SPI inhibited oxidation but the effect was not detected sensorially. Significant interactions (p ≤ 0.05) indicated that STP was more effective at higher cooking temperatures and SPI at lower temperatures. Total moisture of the cooked product was significantly greater with STP but no differences in juiciness and tenderness were detected sensorially.     

Textural Characteristics of Queso Blanco

Instrumental evaluation of Queso Blanco texture as influenced by several factors was carried out using the Instron testing machine. Variables investigated were salting temperature of the curd, moisture content, and age of the cheese. Cheese hardness (maximum force) increased linearly with age over a 17-day period and was inversely related to moisture content. Hardness was not significantly affected by salting temperature of the curd. Stress decay under constant strain was greater with curd that had been salted at low temperatures. These observations are of value in process control.     

Effect of Steam-Assisted Hybrid Cooking on Textural Quality Characteristics,Cooking Loss,and Free Moisture Content of Beef

Semitendinosus muscles were cooked in a steam-assisted hybrid oven and also convection ovens at three different oven temperatures (180, 210, and 240°C) until three different end point temperatures [65°C (medium-rare), 72°C (medium), 80°C (medium-well)] were reached. Textural properties of cooked beef were investigated by the Warner Bratzler shear test and texture profile analysis. Cooking loss and free moisture content of muscle tissue was determined for each cooking condition. In addition, sensory analysis was carried out in order to compare with the instrumental results and correlations between instrumental texture parameters and sensory results. Steam-assisted hybrid oven cooking of beef resulted in a tougher texture, higher cooking loss, and lower free moisture content than convection cooking. High correlation coefficients (r² > 0.70) were observed between instrumental texture measurements and sensory results for all ovens, especially in terms of tenderness. The free moisture content and adhesiveness values were also correlated well with juiciness (r² > 0.70) for all oven types.     

蒸煮与微波加热对牛肉肌内脂肪中脂肪酸组成的影响

取中国黄牛(公牛)的半腱肌(n=10)用来测定不同加工方式(蒸煮和微波加热)处理在不同中心温度水平(60、70、80 ℃)条件下脂肪酸组成的变化.结果显示,肌内脂肪中极性脂肪、中性脂肪及总脂中脂肪酸组成变化不一致.蒸煮时中性脂肪(NL)中多不饱和脂肪酸(PUFA)增加,而饱和脂肪酸(SFA)保持不变,P/S升高.而蒸煮时极性脂肪(PL)和总脂(TL)中PUFA含量减少,SFA含量升高,导致P/S下降.微波加热时NL、PL和TL中SFA显著增加,PUFA含量降低,但极性脂肪(PL)中PUFA含量降低不显著(p＞0.05),导致NL、PL和TL中P/S显著下降(p＜0.05).M/S比值在两种加工条件下基本没变化.在蒸煮和微波加热条件下,n-6/n-3比值在中心温度达到80℃时比加热到60℃或70℃显著升高.结果提示,大理石花纹丰富的牛肉蒸煮烹饪对脂肪酸的保护效果好于微波加热;牛肉应尽量避免在过高温度(80℃)下处理,以减少营养成分的损失,利于人体健康.     

腊肉源酵母菌对发酵牛肉品质特性的影响

在发酵牛肉加工中,添加源于河南信阳腊肉的季巴蒙毕赤酵母以及四川绵阳腊肉的汉逊德巴利酵母作为发酵菌株,以研究特色腊肉源单菌株发酵对发酵牛肉品质的影响,选择地方特色产品和空白作为对照,进行产品水分含量、水分活度（aw）、pH值、蛋白质含量、亚硝胺含量、质构及感官评价等特性指标的测定与分析。结果表明,两株菌株单菌株发酵牛肉硬度适中,弹性和咀嚼性显著高于传统产品,其整体可接受性和传统腊肉未见显著差异,而且水分含量,pH值与亚硝胺含量显著低于传统腊肉制品。综合分析显示两种酵母菌均可作为发酵剂用于发酵肉制品生产,以提升产品品质和安全性。     

高静压对黄桃质构相关组分模拟体系的影响

以黄桃质构相关组分(细胞壁物质)为模拟体系,探究了高静压处理、热处理以及贮藏过程对细胞壁物质持水性及其果胶各组分和纤维素含量变化的影响。结果表明:与热处理相比,高静压处理对细胞壁物质的持水性、果胶各组分含量和纤维素含量均无显著影响。与常温贮藏相比,低温贮藏对高静压处理及热处理的细胞壁物质的持水性、各果胶组分含量和纤维素含量无显著影响。相关性分析显示:碱溶性果胶与水溶性果胶之间,碱溶性果胶、水溶性果胶与持水性之间相关性较高。     

Effect of Inorganic Polyphosphates on Ground Beef Characteristics: Some Chemical, Physical, and Sensory Effects on Frozen Beef Patties

Chemical, physical, and sensory effects of 0.4% sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP) and three commercial phosphate blends were studied in frozen beef patties over a 90-day storage period at ?20°C. Addition of phosphates significantly (P<0.05) increased pH, soluble orthophosphates, Hunter color a values, cook yields and overall acceptability scores. Phosphate addition did not affect (p>0.05) proximate analysis, texture, and flavor scores. Hunter L (lightness) and b (yellowness) values were also unaffected by phosphates. Overall quality of patties, as measured by thiobarbituric acid (TBA) numbers and cooking yields, was improved by all phosphates. There were indications that phosphates interfered with the distillation TBA test.     

Aging and Enhancement Effects on Quality Characteristics of Beef Strip Steaks

ABSTRACT: Strip loins were removed 48 h postmortem from beef sides ( n = 20 pairs) to assess the effects of enhancement before or after aging on quality attributes of beef strip steaks. Strip loins were enhanced to 108% of original weight to contain 0.4% alkaline phosphate, 0.3% salt, 0.1% natural flavoring (on a final weight basis), and added water for comparison with non-enhanced samples. Regardless of when enhancement occurred relative to aging, enhanced samples were more tender, juicy, and salty than their non-enhanced counterparts. Enhanced samples were lighter, less red and less yellow, and had lower L *, a *, and b * values than non-enhanced samples; however, they generally had lower hue angles indicating that their color was closer to the true red axis of the color scale. Samples enhanced before aging achieved maximum tenderness after 14 d, whereas those enhanced after aging experienced no tenderness changes. Warner- Bratzler shear values were lower and pH values were higher in enhanced steaks than in controls.     

Rheological and Textural Characteristics of Date Paste

The rheological properties of two commercial date pastes were investigated in the temperature range of 20–70°C. From typical flow behavior curves, it was observed that date pastes exhibited pseudoplastic behavior. The shear stress-shear rate data were fitted using six common rheological models. The Casson model best described the experimental data at all temperatures. The Arrhenius model described successfully the temperature dependence of apparent viscosity of date pastes (R² > 0.99) with an E_a value in the range of 25,392.6–25,485.7 kJ/kmol. The textural attributes measured were: hardness, springiness, gumminess, cohesiveness, chewiness, and adhesiveness for the texture profile analysis test, and firmness, adhesive force, mean load, and total positive area for the Ottawa test. There was a significant difference in textural attributes between two varieties of date paste studied. Texture profile analysis results showed that all parameters obtained for black date pastes were higher than golden date pastes except for springiness and cohesiveness. However, the Ottawa results showed that golden date pastes were firmer and less adhesive than black date pastes.