The effect of muscle, cooking method and final internal temperature on quality parameters of beef roast

The aim of the study was to evaluate the influence of cooking conditions (dry air and steam) and final internal temperature (75, 85, 95°C) on the physico-chemical properties of beef infraspinatus (INF) and semimembranosus (SEM) muscles as well as their tenderness and juiciness. Cooking method and temperature influenced moisture, total collagen content in cooked meat and cooking loss, whereas muscle type affected fat, total collagen content and cooking loss. Warner-Bratzler shear force values were affected by cooking method, which also influenced juiciness of roasts. Temperature affected tenderness and juiciness, whereas muscle type influenced juiciness. The most desirable tenderness had INF heated in steam and dry air to 95°C. Processing SEM in dry air to 85 and 95°C lowered the juiciness of the roasts. There were significant correlations between physico-chemical, sensorial and image attributes, however high accuracy of prediction (r(2)>0.8) was achieved only for SEM muscle.     

SENSORY PROPERTIES OF PORK, AS INFLUENCED BY COOKING TEMPERATURE AND BREED

Samples of M. longissimus dorsi were taken from identically reared pure bred pigs of the Hampshire (n= 50), Swedish Landrace (n= 30) and Swedish Yorkshire (n= 51) breeds and sensory evaluated after being fried to 60, 68 and 80°C. A sensory profile comprising three juiciness attributes, i.e., visible juiciness, initial juiciness and dryness in mouth, four tenderness attributes, i.e., hardness, stringyness, chewing time and chewing residual, and the attribute elasticity was developed. The relationships between the different attributes were to some extent influenced by final frying temperature. A final frying temperature of 68°C — or even somewhat lower — seems to be the most suitable one from a sensory point of view. The meat is then juicy and tender, no longer having any “rawness” left, as at 60°C. There is a marked influence of breed on the eating quality. Hampshire is more tender and more juicy than Swedish Landrace, which in turn is more tender and more juicy than Swedish Yorkshire. A breed difference was also noted in the susceptibility to heating. A higher loss in eating quality was noted for Hampshire and Swedish Landrace than for Swedish Yorkshire when the final frying temperature was increased. Hampshire had a somewhat higher frying loss than the other two breeds, but it did not result in the least juicy product which indicates that the sensory property juiciness is not directly correlated to the cooking yield.     

Effect of cooking temperature and time on the physico-chemical, histological and sensory properties of female carabeef (buffalo) meat

The effect of cooking temperature (80-100°C) and time (30-60min) on collagen solubility of Semimembranosus muscle in carabeef were investigated. The pH, cooking loss, shear force value, collagen content, collagen solubility, sensory evaluation and histological observations of water bath cooked and pressure cooked Semimembranosus meat samples were measured. Increase in pH, cooking loss, collagen solubility and tenderness scores with decrease in shear force value and collagen content was observed with increases in cooking temperature and time. However, no statistical difference was observed for shear force values, collagen solubility values and tenderness scores in pressure cooked meat and meat cooked in a water bath at 100°C for 45min, inferring that cooking of buffalo meat at 100°C for 45min improved collagen solubility and tenderness to the same extent as that due to pressure cooking.     

The effect of cooking conditions on the eating quality of pork

Two experiments were conducted to examine the effects of cooking parameters, including final internal temperature (65, 72·5 or 80°C), on the eating quality of pork. Assessments were made by a 10-member trained taste panel. In Experiment 1 on loin steaks (m. longissimus) from 28 carcasses weighing 66 ± 1·9 (SD) kg, increasing the final internal temperature from 65 to 80°C had the following effects on mean scores (1-8): tenderness -1·0; juiciness -1·5, pork flavour +0·6 and abnormal flavour -0·5. The medium temperature of 72·5°C was suggested as ideal. In Experiment 2 on leg roasts (m. gluteobiceps) from 96 carcasses weighing 65 + 2·7 (SD) kg, increasing the final internal temperature from 65 to 80°C had the following effects on mean scores (1-8): tenderness -0·2 (not significant), juiciness -0·6, pork flavour +0·3 and abnormal flavour -0·5. The effects of final internal temperature were therefore smaller in roasts and temperatures towards the upper end of the range would be recommended for ideal eating quality, balancing small losses in tenderness and juiciness against gains in flavour scores. Although the experiments were not designed to examine source and sex effects there was evidence that tenderness can be improved through the use of Duroc genes and pelvic suspension of carcasses and no evidence of differences in eating quality between entire males and females.     

Water distribution in porcine M. longissimus dorsi in relation to sensory properties

The water distribution in M. longissimus dorsi (LD) from purebred Hampshire and Swedish Yorkshire pigs was recorded by proton-pulse-NMR. Three domains of water were seen with this type of method, designated as free, extracellular and intracellular water, respectively. The relative proton population for the free water increased from 1·8% in raw, to 3·3% in fried, samples from Hampshire and to 4·2% for the Yorkshire samples. The relaxation time of the extracellular water increased for Hampshire samples from 100 ms, when raw, to 108 ms and 114 ms for samples fried to centre temperatures of 68°C and 80°C, respectively. For Yorkshire samples it decreased from 122 to 108 and 109 ms, respectively. The relative proton population of the extracellular water decreased after frying (raw: 24·5%, 68°C: 18·6% and 80°C: 13·9%) for Hampshire samples, whereas the corresponding populations of protons for those of Yorkshire were 16·5%, 19·2% and 16·6%. The intracellular water had relaxation times of about 40 ms (raw), 30 ms (68°C) and 28 ms (80°C) for both breeds. The relative proton populations were: for Hampshire, 74·1% (raw), 77·7% (68°C), 83·4% (80°C) and, for Yorkshire, 81·6% (raw), 75·5% (68°C) and 77·2% (80°C). On average, the samples of Hampshire were more juicy and tender than those of Yorkshire. The sensory properties were related to the water distribution, but obvious influences of breed and end-point temperature at frying were noted for the relationships. In general, the juiciness and tenderness of fried LD samples could fairly well be predicted by the water distribution in raw meat. However, due to the influence of breed and temperature, different variables are best for the prediction. Also, when the sensory properties were related to the water distribution in fried samples, the influences of breed and end-point temperatures were noted.     

Effect of different air/steam convection cooking methods on turkey breast meat: physical characterization, water status and sensory properties

Turkey breast samples were cooked using a forced convection oven at three relative humidity levels (RH=8, 35 and 88%) at 100°C. Cooking parameters (temperature, cook value, and yield), textural and sensory properties as well as water status of the samples were evaluated. The application of different RH levels resulted in different cooking performances and cooked meat quality. Low steam cooking conditions (RH=35%) significantly increased cooking yield (7% higher than the high steam cooking), moisture content and water-holding capacity and had a positive effect on perceived tenderness, as shown by sensory analysis, where steam cooked samples were perceived as the most tender. The more mobile protons of (1)H T(2) (relaxing at times longer than 1s) in low steam samples were related to the higher perceived tenderness. Low steam cooking allowed for less water consumption, making this process an attractive cooking method as compared to high steam, as it also resulted in higher quality cooked turkey meat.     

Prediction of sensory characteristics of beef by near-infrared spectroscopy

Sensory hardness, tenderness and juiciness of M. Longissimus dorsi muscles from 10 beef carcasses at three ageing stages were predicted by near-infrared (NIR) spectroscopic analysis in the reflection (NIRR) and transmission modes (NIRT) during 14 days ageing at 2°C. Predicting the sensory variables hardness and tenderness from NIRR measurements using principal component regression (PCR), yielded correlation coefficients in the range 0·80-0·90. The root mean square errors of prediction for the predictions of hardness and tenderness were in the range 0·5-0·7, given in sensory assessment units. Juiciness was not well predicted. Prediction of sensory variables from NIRT measurements did not give satisfactory results. Including samples from all carcasses, cows and young bulls in the models resulted in good predictions from NIRR measurements of frozen and thawed samples. However, the best prediction results were generally obtained from separate calibrations of the samples from the bulls. The potential of NIR spectroscopy in the prediction of sensory variables in whole meat needs to be further investigated on a larger number of samples with different breeds, animals and process treatments included.     

Thermomechanical properties of beef muscle

Differential scanning calorimetry (DSC) was used to follow the three major endothermic transitions (T(1), T(2) and T(3)) of beef muscle during heating. Borchardt and Daniels reaction kinetics were used to predict the three time and temperature treatments required to sequentially eliminate each transition. Longissimus dorsi and semimembranosus muscles were removed from beef carcasses suspended by Achilles tendon or pelvis. Samples prepared by heating for 5 min at 57°C (I), 70°C (II) and 81°C (III) were assessed by sensory panel for tenderness, juiciness and residual connective tissue. Weight loss, Warner-Bratzler (W-B) shear and microstructure using transmission electron microscopy (TEM) were also determined. The I treatment showed a significant difference in tenderness and residual connective tissue between muscles, but not between contraction states. The II treatment produced collagen shrinkage and a significant drop in W-B shear and residual connective tissue, coupled with increased tenderness in semimembranosus muscle. An increased W-B value, decreased juiciness, increased weight loss and a reduction in sarcomere and A-band length accompanied the III transition. Muscles from carcasses that had been suspended by the pelvis were found to be significantly more tender than the same muscles from Achilles hung carcasses. It is concluded that DSC is capable of determining amount of protein denaturation and, hence, degree of cooking.     

Diverse lamb genotypes. 3. Eating quality and the relationship between its objective measurement and sensory assessment

The effect of genotype on eating quality was evaluated on m. Longissimus thoracis et lumborum (LTL) muscle of 60 lambs. The lambs were sired by a selection of Texel (T), Poll Dorset (PD), Border Leicester (BL) and Merino (M) rams, crossed with Border Leicester x Merino (BLM) and Merino (M) ewes giving six genotypes (TxBLM, PDxBLM, TxM, PDxM, BLxM and MxM). The relationships between sensory panel assessment of eating quality attributes and pH, cooking loss and shear force were also investigated. No significant differences were observed between genotypes for panel assessment of tenderness, juiciness, aroma liking, aroma strength, flavour liking, overall acceptability and rating. MxM lambs had a significantly (P<0.05) higher flavour strength than BLxM lambs. pH was a poor indicator of any eating quality attributes, except aroma strength (r=0.3, P<0.05). Warner Bratzler shear force value (WB) and tenderness showed a significant (P<0.001) negative correlation (-0.7). Tenderness, flavour and juiciness were the most important sensory attributes, explaining 86.5% of the total variation in overall acceptability.     

DIVERSITY OF PERCEPTIONS OF MEAT TENDERNESS AND JUICINESS BY CONSUMERS: A TIME-INTENSITY STUDY

Seven judges, untrained in sensory assessment, were trained in the use of Time Intensity (TI) and asked to monitor the tenderness and juiciness of a range of cooked beef and pork samples. The subjects were given no definitions concerning sensory cues to monitor in their assessments, nor did they confer with each other. The shapes of the TI curves they recorded for tenderness and juiciness differed between individuals, although there were similarities in the curve shapes for the 2 attributes for each individual. Correlations between the intensity parameters of the curves (maximum intensity and area under curve) and the chewing time were not significant for the subjects as a group for tenderness, although significant correlations were found for some of the subjects when examined individually. The results indicate that subjects differ in their concepts of sensory tenderness and juiciness, and that perceived tenderness does not correlate with chewing time for all subjects. In more general terms the study supports the use of TI assessments for interpreting individual differences in sensory perceptions.     

AGING AND COOKING EFFECTS ON SENSORY TRAITS OF PORK FROM PIGS OF DIFFERENT BREED LINES

The effects of postmortem aging time (2, 9, and 16 days) and endpoint cooking temperature (60, 70, and 80C) on the eating characteristics of pork longissimus (LD) muscle were evaluated. Gilts (n=60) were from 4 different commercial hybrid genotypes (15 pigs/genotype) selected to produce a range of intramuscular fat. Results suggest that LD muscle from genotype 2, which was selected for its propensity to increase marbling had higher intramuscular fat content, tenderness and juiciness scores than that from the other genotypes (P < 0.05). Increasing aging time from 2 to 16 days increased sensory juiciness and tenderness, and decreased instrumental shear force and cooking loss (P < 0.05). Aging for nine days decreased shear force (P < 0.05) but had no effect on tenderness and juiciness scores and cooking loss when compared to 2 days aging. Increasing endpoint temperature increased cooking loss and shear force, and decreased tenderness (P < 0.05) and juiciness.     

MEAT TEXTURE CHARACTERISATION: COMPARISON OF CHEWING PATTERNS, SENSORY AND MECHANICAL MEASURES

The texture of beef, varied by muscle (semimembranosus and semitendinosus), myofibrillar status (ageing time and cold-shortening) and cooking temperature (60C and 80C), was determined by a sensory profile, chewing patterns (determined from surface electromyograms) and mechanical properties of the cooked meats measured at low and high deformation in compression, shear (cutting) and by dynamic (viscoelasticity) tests. The meat factors were discriminated differently by the different measurements showing that they detected differently the various origins of meat texture. Only the maximum modulus before 70% compression and sensory assessments and EMG gave discrimination among all the meat factors. Two main sensory dimensions were found from the profile: juiciness and tenderness with a third related to the determination of elasticity. Juiciness, which varied most between cooking temperatures, was better related to mechanical parameters at low strain rather than high strain and to initial muscular activity rather than later muscular activity. Conversely, tenderness was better related to high strain mechanical properties and to measurements in the middle or later part of the mastication process suggesting that tenderness assessment requires structural disintegration of meat.     

Cooking loss and juiciness of pork in relation to raw meat quality and cooking procedure

The study comprised two experiments with the aim to investigate the influence of raw meat quality and cooking procedure on cooking loss and juiciness of pork. The first experiment determined the cooking loss at 60, 70 and 80 °C centre temperature of 10 raw meat qualities (defined according to ultimate pH, drip loss, breed and rearing conditions) when cooked as steaks on a pan or as a roast in oven at a oven temperature of 90 or 190 °C. The differences in cooking loss between the raw meat qualities and the cooking procedures did decrease as the centre temperature increased and were almost negligble at 80 °C. Low water holding capacity (WHC) and low pH resulted in high cooking loss while no difference in cooking loss was observed between meat having medium or high WHC and pH. In the second experiment four raw meat qualities (standard, Duroc, low pH and heavy carcass weight) chosen from the first experiment to ensure a wide variation in cooking loss, were cooked in oven at 90 or 190 °C oven temperature. Juiciness was assessed three times during the chewing process. The results suggested that juiciness experienced initially in the chewing process depended only on the water content of the meat, whereas juiciness experienced later in the chewing process was determined by a combination of the water and intramuscular fat contents and the saliva production during chewing.     

Comparison of instrumental and sensory evaluation of texture of cured and cooked beef meat

The instrumental and sensory texture attributes of beef muscles (M. longissimus dorsi and M. semimembranosus) were compared after curing and thermal treatments. Shear, compression and puncture tests were carried out with an UTM Instron 4301 and the sensory evaluation was made with the score method. The force values obtained for puncture test gave a greater degree of correlation with the sensory tenderness, hardness and elasticity than the shear test forces. The shear test forces were found to significantly correlate with sensory tenderness only for muscles with perpendicular orientation of fibres to the direction of shear blade movement. The evaluation of beef texture with compression test was dependent on the level of sample deformation degree. The force values of compression were found to correlate significantly with elasticity and juiciness of meat up to 60% deformation levels, but at deformation levels higher than 60% appeared significant correlation with tenderness and hardness. The obtained results showed the usefulness of puncture test with proposed parameters for the instrumental measurements of beef texture.     

Optimization of whey protein concentrate and sodium chloride concentrations and cooking temperature of sous vide cooked whole-muscle beef from Argentina

Response surface methodology was used to optimize the effect of cooking temperature (CT: 65-75°C) and the incorporation of whey protein concentrate (WPC: 0-3.5%) and sodium chloride (NaCl: 0-2.5%) on technological, physical and sensory characteristics of cooked whole-muscle beef. Post-injection weight loss diminished when NaCl concentration increased. Moreover, the increment of both additives produced a reduction of cooking loss. An opposite effect was observed with the increment of CT. As it was expected, a total yield improvement was achieved by increasing both ingredients and diminishing CT. Equivalent yields are achieved complementing both ingredients, meaning that if one ingredient concentration is reduced the other has to be increased. Shear force values were not affected by the studied factors. Instead, lightness was reduced by their increment. At 65°C, injected muscles had lower flavour and odour scores than control. At all CT analyzed, the incorporated brines improved juiciness and tenderness-related attributes. Present results recommend the use of a CT of 70°C and maxima WPC and NaCl concentrations of 2.6% and 1.9%, respectively.     

OBJECTIVE-SUBJECTIVE ASSESSMENT OF MEAT TENDERNESS

Compression, shear, adhesion and cooking loss measurements were compared with sensory assessments of tenderness and juiciness. Multiple regression analyses of compression, shear and cooking loss accounted for 83.4% of the total variance in tenderness for samples presented to the panel as 1.5 cm cubes, and 73.2% for those presented as thin strips cut across the fibers. Cooking losses accounted for about 75 % of the variance in juiciness scores. Regression equations indicated that higher cooking losses, and hence decreased juiciness, increased sensory toughness. The relative contribution of compression (connective tissue toughness) and shear (myofibrillar toughness) measurements varied considerably with sample treatment and fiber orientation of samples as presented to the panel.     

The Effect of Post-Cooking Holding Times on Sensory Assessment of Low- and High-Fat Beefburgers

ABSTRACT: The effect of post-cooking holding-time on sensory assessment of low (89 g/kg) and high (218 g/kg) fat beefburgers was assessed. Burgers were served to panelists approximately 3 or 18 min after cooking. Fat content influenced fattiness, moistness/juiciness and overall appearance (P < 0.05), overall acceptability and overall texture (P< 0.01) and tenderness and crumbliness (p<0.001). Burgers with the higher fat content had higher scores. Holding-time influenced sensory overall appearance only with lower scores at extended holding times (P < 0.01). Treatment differences were small, mostly less than one sensory scale unit. Higher lightness and yellowness values were found for burgers with higher fat contents.     

MODIFIED PREGELATINIZED POTATO STARCH IN LOW-FAT GROUND BEEF PATTIES

Effects of modified pregelatinized potato starch (MPPS) in 5 and 20% fat ground beef patties were evaluated. In formulas containing starch, MPPS comprised 3.0% and added water 5.0% of the raw mixture. Use of 20% rather than 5% fat in the ground beef improved sensory tenderness measured early in chewing, while lowering many Instron measurements. The 20% fat patties had more intense beef flavor. MPPS increased tenderness, but reduced juiciness and beef flavor. The addition (1% of formulation) of concentrated butter flavor to ground beef with MPPS produced beef flavor equivalent to all-beef patties. The use of MPPS increased cooking yields and moisture content following cooking and reduced fat retention of 20% patties. MPPS increased heating rate while retaining substantial moisture during cooking. Inclusion of MPPS in beef patty formulations offers improvements in tenderness and cooking yield, while reducing fat retention during cooking.     

EFFECTS OF COOKING AND SUBSEQUENT REHEATING ON THE PROPERTIES OF LOW-FAT BEEF PATTIES

Low-fat (10%) beef patties manufactured with 0.5% iota carrageenan, were subjected to one-time cooking from the raw to fully cooked state or precooking and later reheating before evaluating sensory, shear force and cooking properties. The samples were reheated in a convection oven or in a simultaneous top and bottom contact grill set either at 121 or 191C. Precooking followed by reheating produced only slight changes in sensory properties (reduced tenderness, increased juiciness and increased beef flavor). Convection oven cooking improved tenderness only for one-time cooked patties. With the double contact grilling system, the 121C surface temperature enhanced tenderness (sensory and shear force) and cooking yields of precooked-reheated patties. Low-fat beef patties formulated with iota carrageenan appear capable of being subjected to a variety of cooking approaches and temperatures without major changes in cooked patty properties.