Cooked yields, color, tenderness, and sensory traits of beef roasts cooked in an oven with steam generation versus a commercial convection oven to different endpoint temperatures

A CVap steam generation oven was compared with a Blodgett convection oven to examine effects on yields, cooked color, tenderness, and sensory traits of beef Longissimus lumborum (LL), Deep pectoralis (DP), and Biceps femoris (BF) muscles cooked to 1 of 3 temperatures (65.6, 71.1, or 76.7°C). Four roasts were cooked in the CVap for a constant time, and 2 roasts were cooked in the Blodgett until they reached target temperatures (3 replications). Cooking yields were higher (P<0.05) for BF and LL roasts in the CVap. Slice shear force (SSF) for BF roasts was lowest (P<0.05) in the CVap but lowest (P<0.05) for DP roasts in the Blodgett. No oven effect (P>0.05) was found for LL roasts. Sensory tenderness for BF roasts in the CVap was higher (P<0.05) than those in the Blodgett. Juiciness was higher (P<0.05) for LL roasts in the Blodgett. The CVap oven offers some tenderization (BF) and cooking yield advantages (BF and DP) over forced-air convection cooking.     

Influence of Rate and Length of Cookery upon Product Attributes of Pre- and Post-Rigor Beef

Paired sides of 15 steer carcasses were used to determine the effects of low temperature, long duration cooking upon muscle (semimembranosus, SM; semitendinosus, ST) shortening, cooking and tenderness attributes of beef roasts that were removed 1 hr (hot-boned, HB) and 48 hr postmortem (cold-boned, CB). The cooking treatments were: (1) 1st hr at 47°C then raised 5.6°C/hr through the 5th hr (69°C); (2) 1st hr at 52°C then raised 5.6°C/hr through the 4th hr (69°C); and (3) 1st hr at 58°C then raised 5.6°C/hr through the 3rd hr (69°C) and thereafter at 80°C until an internal temperature of 66°C was reached. Shear values and panel ratings showed HB roasts to be slightly less tender than CB roasts. Cooking yields were higher for HB than CB roasts.     

Steam Assisted Hybrid Cooking Behavior of Semitendinosus Muscle: Heterocyclic Amines Formation,Soluble Protein Degradation,Fat Retention,Surface Color,and Cooking Value

Beef (Semitendinosus muscle) was cooked in natural convection, forced convection and steam assisted hybrid oven and saturated steam oven at different oven temperatures until the geometric center of samples reached different end temperatures. Heterocyclic amine (HCA) compounds formation, soluble protein degradation kinetics, cook value, changes in fat content, surface colour and overall acceptance of cooked beef were determined. Soluble protein degradation of beef was considered as first order reaction kinetics and the reaction rate constants, k, were determined in the range of 0.014-0.052 min^?1. In steam assisted hybrid oven had higher reaction rate constants compared to that of the convection ovens. The effect of cooking temperature on soluble protein degradation for natural convection, forced convection and steam assisted hybrid oven followed the Arrhenius type of equation with activation energies of 12.45, 14.57 and 60.16 kJ/mol, respectively. Lower HCAs contents, shorter cooking times, lower cook values and lower fat retention were obtained by steam assisted hybrid oven cooking. Steam assisted hybrid cooking could be considered as an alternative cooking method to obtain a healthier product without compromising the eating habits of conventional methods due to better appearance (moderate burned surface) than saturated steam oven samples and a product retaining the most of the nutritional values.     

Turkey Quality as Affected by Ovens of Varying Energy Costs

Energy consumption of microwave, convection, and conventional ovens was monitored as boneless turkey roasts were cooked. The microwave and convection ovens were more energy efficient than was the conventional oven. Total cooking losses and expressible moisture indices did not differ among the roasts. Shear values for microwave roasts were higher than those for convection roasts but were similar to those of conventional roasts. An experienced sensory panel found no differences in doneness, appearance, juiciness, and flavor among roasts after they had been stored in a refrigerator overnight but did find that the microwave roasts were less tender than were the others. A 72-member consumer panel did not express any preferences among the roasts in a multiple-paired comparison test.     

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.     

Palatability of bison semimembranosus and effects of marination

The present study was conducted to investigate the palatability of bison semimembranosus muscle (SM) and the effects of injection with sodium chloride and sodium tripolyphosphate on cooking yield, colour, shear force and consumer acceptability. Twenty paired SM were obtained from 10 intact male bison (aged 24-30 months); each of these muscles was divided longitudinally into two sections. One section was injected to 110% of its original weight to contain 0.5% sodium chloride and 0.3% sodium tripolyphosphate, while the other was kept as a non-injected control. HunterLab a* (redness) and b* (yellowness) values did not differ (P>0.05) between injection treatments; however, injected steaks had lower L* values (darker) compared to controls. Control samples from bison SM were very lean and high in protein but not very tender. Marination by injection was able to significantly reduce shear force values of SM; that is, injected steaks/roasts had significantly (P<0.001) lower shear force values (63.9 N) compared to control samples (102.3 N). Cooking yields for the steaks/roasts from the injected sections were significantly (P<0.001) higher compared to those from control non-injected sections when cooked to either 71 or 77?°C. Bison samples cooked by moist-heat had significantly (P<0.001) lower cooking losses and shear force values compared to those cooked by dry-heat. As expected, steaks/roasts were more tender and had higher cooking yields when cooked to a medium level of doneness (71?°C) compared to an internal temperature of 77?°C (well done). A panel of 80 consumers preferred injected steaks cooked to 77?°C endpoint over other combinations, followed by non-injected steaks cooked to 71?°C, whereas injected steaks cooked to 71?°C and non-injected steaks cooked to 77?°C were equally but least preferred. Hence, injection seems to be protecting against moisture loss at high end-point cooking temperatures.     

The Effects of Marination and Cooking Regimes on the Waterbinding Properties and Tenderness of Beef and Bison Top Round Roasts

ABSTRACT: The combined effect of marination and different cooking regimes on the cooking yield and palat-ability of bison and beef top round roasts was investigated. Semimembranosus (SM) muscles from beef and bison top rounds were injected with a marinade to achieve 20% extension by weight and 0.5% sodium chloride and 0.3% sodium tripolyphosphate levels and then subdivided into 4 roasts and cooked by following 4 cooking regimes: cooking at a constant temperature of 75°C (control; C); similar to the control treatment except that roasts were held at an internal temperature of 55°C for 45 min (Hold45) or 90 min (Hold90) prior to final cooking at 75°C; initial cooking at 55°C with a 5°C increase in oven temperature every hour (Step-up) until the 71°C internal temperature was achieved. Cooking yield, expressible moisture, purge, and shear force of processed roasts were determined. Marination by injection improved the yield and tenderness of beef and bison SM roasts. The cooking yield for injected samples (78%) was significantly (P < 0.05) higher compared with noninjected controls (68%). Injected SM roasts from bison had lower cooking losses than those from beef, whereas control samples from these 2 species did not differ in their cooking yields. Injected beef SM was more tender than bison SM; however, marination significantly reduced the shear force values of SM roasts for both species (i.e., shear force values of 82 N in control samples was reduced to 63 N in injected ones). The cooking regimes, Hold45, Hold90, and Step-up (which allowed a longer time at 55 to 60°C), gave products with lower ( P < 0.05) shear force values than those of the controls. Based on the cooking yield and time involved, the Hold 45 treatment performed the best.     

Tenderness and collagen composition of beef semitendinosus roasts cooked by conventional convective cooking and modeled, multi-stage, convective cooking

Beef semitendinosus roasts were cooked in a forced-air convection oven using conventional or modeled, multi-stage cooking. Conventional cooking was defined as cooking at 163°C to a core endpoint of 65°C. The model method was developed using a finite difference heat and mass transfer model optimized for a three-stage cooking process that included preheating, holding, and finishing. Model cooking resulted in lower (P<0.05) Warner–Bratlzer peak shear force values than conventional cooking (3.3 vs 4.7 kg). Collagen total unaltered fraction was lower (44 vs 55%, P=0.05) and enzyme labile fraction was higher (56 vs 45%, P<0.05) in the model-cooked samples than in conventionally cooked samples. The three-stage cooking process results in a more tender product without adversely affecting product yield.     

External Fat Cover Influence on Raw and Cooked Beef 2. Cooking Time, Losses, Press Fluid and Shear Force Values

SUMMARY: The semitendinosus muscle was used in a study of the influence of the external fat cover and the oven temperature on the characteristics of cooked beef. Roasts were cooked either with or without the external fat cover to an internal temperature of 58°C (rare). Two oven temperatures, 163° or 218°C, were used. The roasts cooked at 218°C required a shorter time in the oven than did the roasts cooked at 163°C but the presence or absence of the external fat cover had very little effect on the min per lb. Roasting at an oven temperature of 218°C caused significantly greater total cooking losses than roasting at 163°C. The cooking losses were increased significantly by cooking the roasts with the fat cover on, as compared with removing the external fat The increase was mainly due to an increase in the drip losses. The presence or absence of the external fat cover had a significant influence on the quantity of press fluid obtained from the samples. A greater amount of fluid was pressed from the roasts without the fat cover. The posterior ends of the muscle were more tender (as indicated by Warner Bratzler shear force values) than the anteriomr ends. The lower oven temperature also caused significantly more tender roasts.     

Electrical Stimulation, Hot-Boning and Prerigor Cookery Effects on Lamb Longissimus Tenderness

Paired halves of 32 lamb carcasses were either electrically stimulated (ES) or not (NES), then assigned to one of the following treatments: (1) hot-boned, cooked prerigor, frozen and reheated (HEPRC); (2) conventionally chilled and boned, cooked, frozen and reheated (CB-ARC); (3) hot-boned, frozen and cooked (HB); and (4) cold- boned, frozen and cooked (CB). Electrical stimulation lowered (P < 0.05) peak force (PF) of chops from CB-ARC, HB and CB treatments. Nonstimulated HB-PRC chops had a lower (P < 0.05) PF than ES, HB-PRC chops. Lower (P < 0.05) compression values were noted for HEPRC and CB-ARC chops than for HB and CB chops. Electrical stimulation reduced (P < 0.05) PF regardless of cooking method. Chops cooked in the microwave had lower (P < 0.05) work values than chops cooked in the convection oven.     

Differences Between Conventionally Cooked Top Round Roasts and Semimembranosus Muscle Strips Cooked in a Model System

Roasts cooked at 177°C by dry (OR) or moist (OFB) heat to 60°C were compared with muscle strips cooked in a model system to 60°C at a rate similar to oven raosting 1.4-kg roasts at 177°C. OFB roasts were less tender, less juicy, had less rare beef flavor, less red and yellow color, more total cooking loss, and shorter cooking time than did OR roasts. Strips had lower values for Instron measurements of hardness, chewiness, shear cohesiveness, and firmness than did OR or OFB roasts. Although strips were cooked in a moist atmosphere, they were more like OR roasts than like OFB roasts. Variance for a given measurement was similar between roasts and strips.     

Effects of Electrical Stimulation and Hot-Boning on Physical Changes, Cooking Time and Losses, and Tenderness of Beet Roasts

Beef semimembranosus and semitendinosus muscles were removed prerigor (1 hr postmortem) and postrigor (7 days postmortem) after one-half of the left and right sides were electrically stimulated. The influence of electrical stimulation and hot-boning upon physical changes; cooking losses; shear force; taste panel evaluation; and time required to heat product to an internal temperature of 63°C was studied. There was no consistent influence of electrical stimulation upon physical changes of prerigor muscles or upon tenderness of pre– or postrigor roasts. Hot-boned and precooked roasts were less tender than cold-boned counterparts. Cooking yields were not altered by electrical stimulation. Prerigor roasts had 9% higher yields than postrigor roasts. Prerigor roasts from electrically stimulated sides required a longer time to cook to 63°C than roasts from the control sides. Hot-boning reduced the length of time of cooking (95 min/kg to 72 mm/kg of raw weight).     

Meat and storage effects on processing characteristics of beef roasts

Two experiments were done to determine the effect of storage conditions and meat cut on the processing characteristics of beef roasts. The first experiment examined the effect of storage condition (fresh/frozen), cap on/off, thawing regime and holding time post thawing on purge, brine uptake, cook yield and colour of raw and cooked roasts. The second experiment examined the effect of meat cut (insides/flats) and chilled storage for up to 8 weeks on processing characteristics of roast beef. Purge was greater for insides stored frozen without cap and air thawed. Frozen thawed cuts had increased brine retention after injection, after tumbling and after cooking. Flats had less purge and higher cook yields when manufactured into roast beef. Raw and cooked colour was not significantly affected by most factors investigated. Raw meat was more red than meat that had been frozen.     

Oxidative Stability and Sensory Attributes of Prerigor Cooked Beef Steak

Beef sirloin tip steaks from 12 steer carcasses were cooked prerigor and postrigor using three heating methods and stored at 4 °C or ‐20 °C. Prerigor cooked steak had lower cook loss, higher pH, higher shear force, and sensory hardness than postrigor cooked steak. Conventional oven cooking produced the lowest cook loss for prerigor steak. Prerigor cooked steak had lower thiobarbituric acid value than postrigor cooked samples after 2 wks at 4 °C or 3 mo at ‐20 °C. Sensory warmed‐over flavor intensity scores were low and showed no differences between prerigor and postrigor cooked steaks for refrigerated or frozen samples.     

LOW TEMPERATURE ROASTING OF THAWED OR FROZEN PORK LOINS

The effects of oven temperature (93, 121, 149, or 163°C) and state (thawed or frozen) on 64 loin roasts from 8 pigs were studied. Frozen roasts required 1.3 times longer to cook, were more juicy and acceptable, and contained more moisture than thawed roasts. Roasting at 121°C produced the least losses and no difference in meat palatability from the higher oven temperatures. The 93°C oven temperature produced the least juicy but the most tender muscle with the longest cooking times and highest losses. Animals were the largest source of variance in 14 of the 19 cooking and palatability traits studied.     

Influence of Storage Times After Cooking on Warner-Bratzler Shear Values of Beef Roasts

Fifty longissimus and 49 biceps femoris roasts were cut from five Choice-grade steer carcasses and used to evaluate differences in Warner-Bratzler shear values at different times after cooking. Five longissimus roasts and four or five biceps femoris roasts were cut from both sides of each carcass. Roasts were cooked to an internal temperature of 71°C then wrapped in aluminum foil and chilled (4°C) for 2, 24, 48, 72 or 168 hr prior to shear analysis. No differences in shear values by carcass side or by length of chill after cooking existed for biceps femoris roasts. Longissimus roasts were more tender when taken from the left side and when chilled for 2 hr vs longer chill periods. Roasts chilled for 24, 48, 72 or 168 hr had similar shear values. Cores taken from the medial portion of the longissimus roasts had lower shear values than cores taken from the central or lateral portions. Longissimus roasts were always more tender than roasts from the biceps femoris muscle and they were less variable in tenderness.     

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.     

PHYSICAL CHARACTERISTICS OF BEEF ROASTS PREPARED WITH DIFFERENT FOODSERVICE COOKING METHODS

Effects of cooking rate, fat trim level, aging period, endpoint temperature and oven type (conventional, forced air convection and forced air/steam combination) on yield, composition and cooking parameters for eight types of beef roasts were investigated. Generally, fast cooking, higher endpoint temperatures, complete removal of external fat and the use of forced air/steam combination ovens increased cooking losses. Fast cooking rates and forced air/steam combination ovens increased moisture loss in some roasts. Reduced levels of external fat did not dramatically affect yields or relative changes in composition due to cooking, but did increase cooking time per unit weight. Forced air/steam combination ovens may reduce the required length of preparation per unit raw weight while conventional ovens may increase cooking time. Rapid cooking of larger roasts with moist heat increased postcooking temperature rise. These results should aid in the revision of foodservice beef cookery guidelines.     

Effects of brine ingredients and temperature on cook yields and tenderness of pre-rigor processed roast beef

In semimembranosus (SM) muscles removed pre- and post-rigor and injected 10% (wt/wt) with brines formulated to give 2% salt, 1.5% glucose, 0.3% phosphate, 0.15% calcium chloride or 3% sodium lactate in the finished product and cooked within 1 h of injection, cook yields were not significantly affected by processing pre- or post-rigor. Within treatments, however, brine composition had a significant (P < 0.05) effect on cook yields; highest yields were obtained using salt (although this was not significantly different from the water injected control) and lowest yields with calcium chloride. Adding phosphate resulted in lower peak shear force values, and less energy was required to break the sample. The most tender roasts from pre-rigor meat were produced using salt, phosphate or lactate brines and the least tender using calcium chloride. Brine temperature (0-12 °C) during injection had little effect on cook yields or tenderness of the roast beef manufactured pre-rigor. The results indicate that accelerated processing of roast beef can result in finished product with acceptable yields and tenderness if salt and phosphate brines are used.     

Cookery method and end-point temperature can affect the Warner-Bratzler shear force, cooking loss, and internal cooked color of beef longissimus steaks

Steaks from 60 beef ribeye rolls were used to test the interactive effects of cookery method and end-point temperature on Warner-Bratzler shear force (WBSF) and internal cooked color. Pairs of longissimus thoracis (LT) steaks were assigned to combinations of 3 different end-point temperatures and 5 cookery methods. The forced-air convection oven (FAC) required the longest time and produced the reddest internal color, regardless of end-point temperature. The clam-shell grill (CLAM) required the least cooking time and resulted in the lowest cooking losses, but CLAM-cooked steaks also had the greatest WBSF values and least red internal color. Repeatability values for WBSF were acceptable (>0.60) for all degrees of doneness when steaks were cooked in the FAC and impingement oven, but steaks cooked on the CLAM were not repeatable. The relationship of myofibrillar toughening, moisture loss and cooked color changes in beef LT steaks also differed due to cookery methods.