Effect of Cooking on Cholesterol Content of Patties Containing Different Amounts of Beef, Textured Soy Protein and Fat

Ground beef patties were prepared to contain 0, 10, 20 or 30% rehydrated textured soy protein (TSP) and 8, 16 or 27% fat. Patties were cooked from the frozen state on a rack in a preheated oven at 177°C to an endpoint internal temperature of 75°C. The cholesterol content of raw ground beef patties decreased as the amount of TSP increased and also decreased as the fat content decreased from 27 to 16 or 8%. At initial fat levels of 8 and 16%, there were no significant differences in cholesterol retention (per-patty basis) during cooking among patties with initial TSP (rehydrated) levels of 0, 10, 20 and 30%; at an initial fat level of 27%, however, patties containing TSP (10, 20 or 30%) retained substantially higher (P < 0.05) amounts of cholesterol when cooked than did those without TSP.     

ADDITION OF CORN GLUTEN MEAL AND ZEIN TO GROUND PORK OF VARIOUS FAT PERCENTAGES1

Corn gluten meal and zein at levels of 0, 2.5 and 5% were added to ground pork of three fat percentages. Raw patties were analyzed for fat, moisture, protein contents and color. Selected patties, broiled to 77°C, were evaluated for proximate composition, total cooking loss, color and Instron compression. Five percent zein added to ground pork reduced cooking loss 4.2% when compared with ground pork without zein. Addition of corn gluten meal to pork did not influence yield. Instron compression values increased with the addition of zein and corn gluten meal. Increased fat altered the hue (increased hue angle due to increased b) of the interior of the cooked pork patties. Zein addition also increased the lightness of cooked pork patties. The addition of zein to ground pork patties decreased sensory tenderness and pork flavor intensity and increased off-flavor intensity.     

The storage stability and textural, physico-chemical and sensory quality of low-fat ground pork patties with Carrageenan as fat replacer

Low‐fat ground pork patties (<10% total fat) made with carrageenan added at either 0.25, 0.50 or 0.75% final concentration were processed and the compositional and sensory characteristics compared with control patties which contained 20% fat. The moisture content of raw and cooked low‐fat patties was significantly (P < 0.05) higher than control patties because of greater amounts of water added during formulation. Cooking yield, fat and moisture retention also improved significantly (P < 0.05) in low‐fat patties that had carrageenan incorporated when compared to a control product. The dimensions of the low‐fat patties were maintained better than those of the control product during cooking. The sensory attributes of low‐fat patties with 0.5% carrageenan were similar to those of the high‐fat control. The lipid profile revealed as much as a 47.7 or 44.1% decrease in total lipids and cholesterol content respectively, compared with the controls. The calorie content was reduced by 31.1% in low‐fat cooked patties compared with the controls. The texture profile of low‐fat patties that had been made with 0.5% carrageenan were similar to control patties with only a slight increase in hardness and gumminess in the low‐fat product. The low‐fat ground pork patties made in the present study remained stable without any appreciable loss of physico‐chemical, microbiological and organoleptic quality during refrigerated storage (4 ± 1 °C) for 21 and 35 days in aerobic and vacuum packaging respectively.     

Chemical, Physical, and Sensory Characterization of Ground Beef Containing 5 to 30 Percent Fat

Ground beef patties containing 5, 10, 15, 20, 25, and 30% fat were evaluated raw and after cooking to either 71 or 77°C. Cooking losses were lowest for 5–20% fat patties (24.7-26.0%), intermediate for 25% fat patties (28.9%), and highest for 30% fat patties (32.1%). Low-fat patties (5 and 10%) were firmer in texture, more crumbly at end-of-chewing, less juicy and flavorful, and caused less oily coating of the mouth than 20–30% fat patties. Warner-Bratzler and Lee-Kramer shear forces decreased as fat increased. Instron texture profile analysis also indicated greater peak forces, springiness, and cohesiveness for low-fat patties. Cooking to 77 vs 71°C accentuated differences in palatability between low- and high-fat patties.     

Effects of Metmyoglobin Reducing Activity and Thermal Stability of NADH‐Dependent Reductase and Lactate Dehydrogenase on Premature Browning in Ground Beef

Premature browning is a condition wherein ground beef exhibits a well‐done appearance before reaching the USDA recommended internal cooked meat temperature of 71.1 °C; however, the mechanism is unclear. The objectives of this study were: (1) to determine the effects of packaging and temperature on metmyoglobin reducing activity (MRA) of cooked ground beef patties and (2) to assess the effects of temperature and pH on thermal stability of NADH‐dependent reductase, lactate dehydrogenase (LDH), and oxymyoglobin (OxyMb) in‐vitro. Beef patties (lean: fat = 85:15) were packaged in high‐oxygen modified atmosphere (HiOX‐MAP) or vacuum (VP) and cooked to either 65 or 71 °C. Internal meat color and MRA of both raw and cooked patties were determined. Purified NADH‐dependent reductase and LDH were used to determine the effects of pH and temperature on enzyme activity. MRA of cooked patties was temperature and packaging dependent (P < 0.05). Vacuum packaged patties cooked to 71 °C had greater (P < 0.05) MRA than HiOX‐MAP counterparts. Thermal stability of OxyMb, NADH‐dependent reductase, and LDH were different and pH‐dependent. LDH was able to generate NADH at 84 °C; whereas NADH‐dependent reductase was least stable to heat. The results suggest that patties have MRA at cooking temperatures, which can influence cooked meat color.     

Display Life and Internal Cooked Color of Ground Beef from Vitamin E-Supplemented Steers

The retail display life of fresh ground meat and the internal color of patties cooked to four endpoint temperatures (55, 65, 71, and 77°C) were determined for ground beef (10% fat) from vitamin E-supplemented (500 and 2000 IU) or nonsupplemented steers. Vitamin E supplementation increased (P < 0.05) the retail dissolve life of the meat by 12 and 42 lir for 500 and 2000 IU, respectively Vitamin E did not akect (P > 0.05) internal cooked color or expressible juice color of the patties, and it did not cause premature browning or persistent redness. Increased levels of vitamin E supplementation decreased (P < 0.05) TBA values but had no effect on total reducing activity or oxidation-reduction potential.     

Fat and Cholesterol Content of Beef Patties as Affected by Supercritical CO2 Extraction

Beef patties (raw, raw freeze-dried, cooked, and cooked freeze-dried) were prepared for treatment with supercritical carbon dioxide extraction (SC-CO). Each type of patty was then assigned to one of four treatments: control, static extraction at 170 atm/50°C, dynamic extraction at 170 atm/50°C and dynamic extraction at 544 atm/40°C. Freeze drying of the patties prior to SC-CO₂ extraction improved removal of fat and cholesterol. Freeze drying enhanced (P<0.01) cholesterol extraction; however, precooking had limited effects (P>0.05) on cholesterol extraction. Supercritical fluid extraction could be effective to reduce the fat and cholesterol content of preformed meat products, without requiring communication of the sample.     

Effect of erythorbic acid on cooked color in ground beef

Consumers often use the color of cooked ground beef as an indicator of doneness. For safety reasons, it is recommended that the center of ground beef products be heated to 71°C. In some instances beef may appear done before reaching 71°C, a condition termed premature browning (PMB). Ground beef (15% fat), with added erythorbic acid (ERY) at 0.04 and 0.06% was formed into patties, wrapped in oxygen permeable film, and stored in the dark at 4°C. Patties were stored for either 10 h or 58 h and then cooked to internal end point temperatures of 60, 66, 71 or 77°C. Internal cooked color L(?), a(?) and b(?) values were measured. For beef patties stored 10 h, there was no effect of ERY on internal cooked color. After 58 h storage, ground beef with 0.04 and 0.06% ERY had higher a(?) values than controls at 60°C (P<0.05). Beef with 0.04% ERY cooked to an internal temperature of 66°C had higher a(?) values than 0.06% ERY and controls (P<0.05). There was no effect of ERY on color of beef patties cooked to 71 or 77°C. The presence of 0.04% ERY in ground beef patties stored 58 h appeared to maintain red color at internal temperatures of 60 and 66°C.     

Lipid Oxidation Potential of Beef, Chicken, and Pork

Beef and pork longissimus dorsi and semimembranosus muscles and chicken breast and thigh muscles were excised 24 hr postmortem from carcasses of marketweight grain-finished feedlot beef cattle, marke-tweight hogs on a typical finishing diet, and broilers on a commercial grain diet. Muscle samples were immediately ground and formed into patties and stored raw or after cooking, at 4°C (cooked) or ?20°C (raw and cooked). TBA values (on sample weight basis) of frozen raw samples were higher for beef and pork than for chicken, as was heme iron content. However, TBA values of cooked samples were highest for chicken thigh muscles, which contained the most polyunsaturated fatty acids, at all storage temperatures.     

Comparison of antioxidant effects of milk mineral, butylated hydroxytoluene and sodium tripolyphosphate in raw and cooked ground pork

The antioxidant effects of 0.5-2.0% milk mineral (MM) was tested in raw and cooked ground pork stored at 2?°C or -20?°C, compared to butylated hydroxytoluene (BHT) and sodium tripolyphosphate (STP). TBA numbers were low and not different between raw meat treatments. TBA numbers were lower (P<0.01) for cooked treatments with MM or STP compared to controls or treatments with BHT. Experiments were also done to determine acceptability of pork samples with various TBA values, and to determine effect of holding time before serving on TBA values. Cooked pork patties held at 71?°C for 90 or 120 min had higher (P<0.05) TBA values than patties held for 0-60 min. Thus patties could be warmed for 60 min after cooking without significantly increasing TBA number. For paired-preference sensory testing, patties were cooked and stored at 2?°C for 0, 1, 2 and 3 days to obtain TBA numbers of 0.4, 1.5, 3.4 and 3.9 respectively. Panelists preferred (P<0.001) patties with TBA number <0.5, compared to patties with TBA numbers >1.4.     

TBA Values and 7-Ketocholesterol in Refrigerated Raw and Cooked Ground Beef

Thiobarbituric acid (TBA) values and 7-ketocholesterol were determined on raw and cooked ground beef patties after 0, 2, and 4 days of storage at 4°C. The mean 7-ketocholesterol at days 0, 2, and 4 was 9.65, 23.8, and 42.3 μg for 100g raw patties and 6.33, 277.9, and 484.7 kg for 100g cooked patties. The TBA values increased after 2 and 4 days for the raw and cooked patties. TBA values and 7-ketocholesterol were correlated with each other for raw (r²= 0.82) and cooked (r²= 0.98) patties. The peak suspected to be 7-ketocholesterol was confirmed by mass spectral analysis. The 7-ketocholesterol in the cooked patties stored two days represented a 0.3% oxidation of the free cholesterol.     

Composition, Cooking Loss, Color and Compression of Ground Pork with Dry- and Wet-Milled Corn Germ Meals

Dry- and wet-milled corn germ flour at levels of 0, 2.5 and 5% were added to ground pork of three fat percentages. Raw patties were analyzed for fat, moisture and protein contents and for color. Selected patties, broiled to 77°C, were evaluated for proximate composition, total cooking loss, color and Instron compression. Dry- and wet-milled germ flour addition at the 5% level decreased cooking losses 9 and 7.5%, respectively, when compared with control patties. Instron compression values decreased as the amount of dry-milled germ flour increased. The yellow color (b-value) increased and lightness (L-value) decreased with addition of wet-milled corn germ flour.     

Influence of Rapid Cooking Methods on the Survival of Trichinella spiralis in Pork Chops from Experimentally Infected Pigs

Pork chops (1.3, 2.5 or 3.8 cm thick) cooked to an internal temperature of 17 or 77°C by conventional oven, convection oven or flat grill contained no motile trichinae, whereas chops cooked to 66°C sometimes contained motile trichinae. Chops cooked by either charbroil or deep fat fry and pretreated in a microwave oven sometimes had motile trichinae even after cooking to an end point of 77°C. Chops, which had been frozen for 18 hr at -23°C and were thawed by microwave to 0°C then deep fat fried to an end point temperature, sometimes had infectious trichinae as confirmed by tests with rats and mice. Additional research is underway to verify the thermal death times and temperatures for T. spiralis larvae.     

Influence of bleached palm oil on the physicochemical and sensory properties of beef patty

The effect of palm oil on the physico-chemical and sensory properties of beef liver patty were studied. Seven batches (3units per batch) of beef liver patty with different palm oil content (5, 10, 20, 30, 40 and 50%) and a control with pork fat (30%) were manufactured by component mix at 1500 rpm for 1 min and cooked in an oven at 90?°C. Physico-chemical analysis of raw and cooked samples showed improvement of emulsion stability, water binding capacity, technological yield and hardness of patties substituted with lower proportions of deodorized bleached palm oil. No significant difference (P?>?0.05) was found between physico-chemical properties of liver patty formulated with 20% palm oil and the control (formulated with 30% pork fat). Sensory attributes generated by a semi-trained panel based mainly on texture, homogeneity (colour and aspect), odour and meltiness of the patties confirmed this tendency.     

Sensory, Shear, and Cooking Properties of Lower-Fat Beef Patties Made with Inner Pea Fiber

Lower fat (10% and 14%) ground beef patties containing inner pea fiber as dry powder or as part of a high fat mixture were compared to all‐beef patties (10%, 14%, and 18% fat). Patties processed with pea fiber had improved tenderness and cooking yields and showed less change in thickness during cooking, but required longer cooking times to reach 71 °C compared to all‐beef controls. Beef flavor intensity of pea fiber patties did not differ from 10% and 14% fat all‐beef patties. Different forms of pea fiber usage produced similar patty properties. Use of inner pea fiber in lower fat beef patties improved tenderness and cooking yield, without negative effects on juiciness and flavor.     

Effect of muscle source on premature browning in ground beef

Premature browning (PMB) describes cooked beef that may appear done before reaching 71 °C. Ground beef from paired Longissimus lumborum (LL) and Psoas major (PM) muscles was formed into patties. Patties were cooked immediately, and after 48 and 96 h storage at 4 °C. Total reducing activity (TRA) and external color were measured immediately prior to cooking. Patties were cooked to internal end point temperatures of 60, 66, 71 or 77 °C and internal cooked color (L(*), a(*) and b(*) values) was measured. Raw PM patties had greater L(*) values and lesser a(*) values than those from LL (P<0.05). For LL and PM, raw a(*) and b(*) values decreased with storage from 0 h to 96 h (P<0.05). At 0 and 48 h storage, cooked patties prepared from PM had greater a(*) values than those prepared from LL at all internal endpoint temperatures (P<0.05). Internal cooked a(*) values of patties from PM decreased with storage of raw patties, whereas it was stable for LL patties (P<0.05).     

Effect of natural antioxidants on oxidative stability of cooked, refrigerated beef and pork

ABSTRACT:  The effect of grape seed extract (GS; 0.01% and 0.02%), oleoresin rosemary (OR; 0.02%) and water-soluble oregano extract (WS; 0.02%) on oxidative and color stability of cooked beef and pork patties stored at 4 °C for 8 d was determined. Fresh beef or pork lean and trim were ground, mixed (30% fat), and divided into 5 portions. Antioxidants mixed with salt (2%) were added. Patties were formed, cooked to an internal temperature of 71 °C, overwrapped in PVC, and stored at 4 °C. Lipid oxidation, assessed using thiobarbituric acid reactive substances (TBARS) and sensory evaluation, instrumental and visual color, and pH were determined after 0, 2, 4, 6, and 8 d. Based on TBARS values and off-odors associated with lipid oxidation such as rancidity, wet cardboard (for beef patties), and grassy (for beef and pork patties), grape seed extract resulted in the best antioxidant activity in both meat species. It did not change instrumental color measures of redness, yellowness, or color intensity, and appeared to reduce visual green discoloration in beef patties. The higher GS concentration (0.02%) exhibited more antioxidant activity than the lower concentration (0.01%). Therefore, grape seed extract at 0.02% has the potential to reduce oxidative rancidity and improve shelf life of refrigerated cooked beef and pork patties.     

Effect of erythorbate, storage and high-oxygen packaging on premature browning in ground beef

Premature browning (PMB) was investigated in ground beef patties with (0.04%, w/w) and without erythorbate. In Experiment 1, patties were stored at 4 °C for 48 h; at -18 °C for 21 days; or at -18 °C for 21 days, thawed at 4 °C for 24 h; and cooked. Bulk ground beef was stored at -18 °C for 24 days, thawed for 24 h at 4 °C, and patties prepared and cooked immediately. In Experiment 2, fresh patties were overwrapped with oxygen-permeable film or packaged in 80% O(2)/20% N(2) (MAP), and stored for 48 h at 4 °C, or at -18 °C for 21 days, and cooked. Total reducing activity and color (L*, a* and b* values) were measured immediately prior to cooking. Patties were cooked to internal temperatures of 60, 66, 71 and 77 °C and internal cooked color was measured. Total reducing activity was higher for the erythorbate treatment than controls for all storage conditions (P<0.05). a* Values of cooked patties were higher for erythorbate than control treatments under all storage and packaging conditions at 60 and 66 °C (P<0.05). The presence of erythorbate in ground beef patties appeared to maintain red color at cooked internal temperatures of 60 and 66 °C. Frozen bulk storage appeared to increase the susceptibility of ground beef to PMB when compared to fresh and frozen patties. Patties cooked directly from frozen state appeared less susceptible to PMB than frozen-thawed and bulk storage. Ground beef appeared predisposed to PMB when stored in high-oxygen MAP at 4 °C for 48 h.     

Microwave Cooking Properties of Ground Pork Patties as Affected by Various Fat Levels

ABSTRACT: Ground pork patties were processed from pork hams to achieve fat levels of 5%, 10%, 15%, 20%, and 25%. Each patty was cooked in a microwave oven to 75 °C from a thawed state. As fat levels increased, cooking time decreased. Total cooking loss and drip loss were highest for 25% fat patties and lowest for 5% fat patties. High-fat patties (20% and 25%) had greater reductions in dia than did 5% to 15% fat patties, but had less change in patty thickness. Shear force values decreased as fat levels increased. Visual evaluations also indicated a greater presence of air pockets in high-fat patties. In raw patties, low-fat samples were darker (had lower L * values) and were redder (had higher a * values) than patties with more fat. However, these differences were relatively smaller when the patties were cooked. As fat levels increased, flavor, tenderness, juiciness, and oiliness ratings increased. These differences were not as apparent when comparing among low-fat patties or high-fat patties. Keyword: microwave, cooking, fat, pork patty     

Lipid Oxidation in Ground Beef Patties as Affected by Time-Temperature and Product Packaging Parameters

Oxidative rancidity in fresh and stored ground beef samples was measured using a thiobarbituric acid (TBA) assay with antioxidant protection. The independent variables were fat concentration (15 or 30%), package type (polyethylene or vacuum-packaged), freezer storage temperature (-12.2°, -23.3° or -34.4°C) and storage time (4, 8, 12, 16, or 20 weeks). At the end of each storage time samples were thawed and TBA values were determined on the samples before and after cooking. TBA values increased during the first 12 to 16 weeks after which time it decreased for both the cooked and uncooked samples. The higher fat samples, packaged in polyethylene, had higher TBA values for both cooked and uncooked patties. Uncooked patties stored at - 12.2°C had higher TBA values than those stored at -23.3°C or -34.4°C but cooked sample TBA values showed no dependence on storage temperature.