Cholesterol Content and Sensory Analysis of Ground Beef as Influenced by Fat Level, Heating, and Storage

Twelve treatment combinations including three fat levels, two internal endpoint temperatures, and two storage periods for ground beef patties were studied. Quality and sensory attributes as well as cholesterol content were evaluated. As fat level increased in raw patties, cholesterol content, drip and total cook loss, fat and cholesterol content of cook drip increased whereas red color intensity and evaporative losses decreased. Cholesterol content, evaporative and total losses, and beef-flavor intensity increased with higher internal endpoint temperature. Red color intensity of raw patties and cholesterol content of raw and cooked patties decreased with storage. No differences in cholesterol content could be attributed to fat content of raw product; therefore, choosing low fat ground beef to lower cholesterol may not be justified.     

INSTRUMENTAL AND SENSORY MEASUREMENT OF BEEF PATTY AND SAUSAGE TEXTURE

Beef sausages and beef patties of different texture were produced by varying the fat content in the raw mix over the range 5–30%. Batter shear stress and strain increased linearly with increased fat level (P<0.09 and 0.001, respectively). Although batter shear stress was not related to sensory scores, shear strain was directly related to moistness and inversely related to grittiness scores (P<0.05). Batter sensory moistness increased and firmness and grittiness deceased linearly with fat content (P<0.001). Changes in fat content did not affect the peak force of cooked patties, and there were poor correlations between patty peak force and sensory scores. Patty juiciness and softness increased and patty cohesiveness and chewiness decreased with fat content (P<0.001). Batter cook yield increased and patty cook yield decreased with increasing fat level (P<0.001). Sensory scores, using trained panelists, were more sensitive to the effect of fat content on patty and sausage texture than instrumental measurements.     

Enhancement of the nutritional status of beef patties by adding flaxseed flour

Flaxseed flour was used as a functional ingredient in the production of beef patties. Beef patties were produced with five different formulations; the addition of 3%, 6%, 9%, 12% and 15% flaxseed flour. Control samples were formulated with 10% and 20% fat addition. Raw and cooked beef patties were analyzed for moisture, protein, fat, ash, pH, color parameters and fatty acid profiles. Beef patties were evaluated for cooking loss and sensory properties. Fat and ash content of raw patties increased, while moisture and protein content decreased with increased flaxseed flour. The same trend (except fat content) was also observed after cooking. The addition of flaxseed flour did not affect pH values of raw and cooked beef patties. The addition of flaxseed flour improved the cooking loss but, increased the energy value (as kcal/100 g). L and a values of raw beef patties containing flaxseed flour were close to controls with 10% fat. α-linolenic acid content of raw and cooked beef patties increased as the level of flaxseed flour increased. The PUFA/SFA ratio increased from 0.04 in the control with 10% fat to 0.62 in the raw beef patties with 15% flaxseed flour. The n-6/n-3 ratio decreased from 5.76 in the control with 10% fat to 0.36 in the raw beef patties with 15% flaxseed flour. The nutritional status of beef patties was enhanced with minimal composition and sensory changes with 3% or 6% flaxseed flour addition.     

The characteristics of beef patties containing different levels of fat and oat flour

Three concentrations of oat flour (OF), 0, 2 and 4% (w/w), were added to beef patties which had either 5, 10 or 20% fat levels. Raw and cooked patties were analysed for protein, fat, moisture, ash and pH. Patties were further evaluated for cooking characteristics, colour parameters (L*, a*, b*) and sensory properties. Moisture content decreased in raw patties as a result of the addition of OF but OF increased the moisture content of cooked patties. OF addition did not change the protein, fat and ash contents of either raw or cooked patties. Increasing fat concentration decreased cooking yield. OF improved the cooking characteristics of patties. Reducing the fat significantly decreased the lightness values of patties. Patties with OF had slightly higher b* values than control treatments. Increasing fat level increased juiciness, flavour and texture scores and 4% OF increased the juiciness scores, OF had no effect on other sensory properties.     

PHYSICAL AND SENSORY PROPERTIES OF LEAN GROUND BEEF PATTIES CONTAINING METHYLCELLULOSE AND HYDROXYPROPYLMETHYLCELLULOSE1

Broiled, lean ground beef patties containing no additives, two levels of methylcellulose (MC, 0.5 or 1.0%) and two levels of hydroxypropylmethylcellulose (HPMC, 0.5 or 1.0%) were evaluated for raw and cooked composition, cooking losses, sensory attributes and Instron compression measurements. MC or HPMC addition did not significantly affect the fat, moisture or protein content of the raw and cooked patties. Patties containing HPMC received greater tenderness, juiciness and off-flavor sensory scores when compared with patties containing MC or no additive. MC or HPMC addition increased patty gumminess sensory scores and decreased Instron compression values. Sensory cooked meat flavor decreased with gum addition.     

Effect of oat's soluble fibre (β-glucan) as a fat replacer on physical, chemical, microbiological and sensory properties of low-fat beef patties

This study evaluated the effect of adding oat fibre source of β-glucan (13.45%) on physical, chemical, microbiological and sensory traits of low-fat (<10%) beef patties as compared to 20% fat control patties. Significant (p<0.05) improvements in cooking yield (74.19%), and retentions of fat (79.74%) and moisture (48.41%) of low-fat patties were attributed to the water binding ability of β-glucan. Because of larger water retentions moisture contents of raw and cooked low-fat patties were higher (p<0.05) than those of the control patties. Cholesterol content was similar across formulations. Low-fat and control beef patties remained stable in microbiological quality during 60days frozen storage. Low-fat patties were found to be of lower degree of likeness in the taste but juicer than control (p<0.05). Besides appearance, tenderness and colour were not affected by the addition of oat's soluble fibre. Oat fibre can be used successfully as a fat substitute in low-fat beef patties.     

Cooked Color in High pH Beef Patties as Related to Fat Content and Cooking from the Frozen or Thawed State

Beef patties were processed from high pH (>6.0) beef to contain 5, 10, 15, 20 or 25% fat. Patties were cooked to 71°C from the frozen or thawed state before evaluating color. Neither fat content nor state of patties when cooked exerted any major influence on color, but linear effects (p<0.01) in association with increased fat content included higher L* values and hue angles and lower a* values (15.2% reduction). Higher values for L*, b* (but not for 5% fat patties), and hue angles were observed for patties cooked thawed rather than frozen. The use of high pH beef lessened the effects of increased fat and cooking from the thawed state on increased brown color in cooked patties.     

Residual triose phosphate isomerase activity and color measurements to determine adequate cooking of ground beef patties

The objectives were to (i) compare the use of triose phosphate isomerase (TPI) activity and internal color scores for determination of cooking adequacy of beef patties and (ii) determine the effect of frozen storage and fat content on residual TPI activity in ground beef. Ground beef patties (24.4% fat) were cooked to five temperatures ranging from 60.0 to 82.2 degrees C. TPI activity decreased as beef patty cooking temperature was increased from 60.0 to 71.1 degrees C; however, no difference (P > 0.05) in activity (6.3 U/kg meat) was observed in patties cooked to 71.1 degrees C and above. Degree of doneness color scores, a* values and b* values, of ground beef patties decreased as internal temperature was increased from 60.0 to 71.1 degrees C; however, temperature had no effect on L* values. TPI activity in raw ground beef after five freeze-thaw cycles did not differ from the control. Three freeze-thaw cycles of raw ground beef resulted in a 57.2% decrease in TPI activity after cooking. TPI activity of cooked beef increased during 2 months of frozen storage, but TPI activity in ground beef stored for 3 months or longer did not differ from the unfrozen control. While past research has shown color to be a poor indicator of adequate thermal processing, our results suggest that undercooked ground beef patties could be distinguished from those that had been adequately cooked following U.S. Department of Agriculture guidelines using residual TPI activity as a marker.     

不同脂肪添加量的牛肉饼在反复冻融过程中的品质变化

探究不同脂肪添加量的牛肉饼在反复冻融过程中,其肌原纤维蛋白氧化、理化性质及感官品质的变化情况,阐明反复冻融、脂肪含量与蛋白氧化之间的关系,并分析由此导致的产品品质变化。将绞碎的牛背部脂肪按比例添加于绞碎的牛背最长肌肉中,分别添加相同的食盐等辅料,制得3组脂肪含量不同的牛肉饼,即未添加牛脂肪组(F_0)、添加10%牛脂肪组(F_(10))和添加20%牛脂肪组(F_(20))。真空包装后于-18℃冷冻贮藏,期间反复冻融5次循环,每次冻融后测定样品的感官品质、硫代巴比妥酸反应产物(thiobarbituric acid resctive substances,TBARS)值、色泽参数、解冻损失率,提取肌原纤维蛋白测定羰基含量、总巯基含量、蛋白溶解度,并通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)观察肌原纤维蛋白的聚集和降解程度。结果表明:随着冻融次数和脂肪含量的增加,牛肉饼的TBARS值、解冻损失率、亮度(L*)值、黄度(b*)值、羰基含量显著增加(P0.05),红度(a*)值、总巯基含量、蛋白溶解性显著降低(P0.05)。SDS-PAGE结果显示,随冻融次数和脂肪含量的增加,肌原纤维蛋白的肌球蛋白重链发生聚合,副肌球蛋白和肌动蛋白发生降解。牛肉饼经油煎熟制后进行感官评价,其品质随脂肪含量增加而提高,但随冻融次数增加而下降,特别是冻融3次之后的牛肉饼质地变硬,多汁性下降。相关性分析表明,冻融次数及脂肪含量均与蛋白氧化指标(羰基、总巯基、蛋白溶解性)及理化指标(TBARS值、解冻损失率、L*、a*、b*)极显著相关(P0.01)。实验表明,反复冻融引起牛肉肌原纤维蛋白氧化,导致牛肉饼品质下降;脂肪含量的增加提高了感官得分,但同时加速了蛋白氧化和理化性质的变化。所以在实际的生产中,适当的脂肪含量可提高牛肉制品的品质,但注意冷冻贮藏要保持温度尽可能低且恒定。     

FUNCTIONAL PROPERTIES OF SORGHUM FLOUR AS AN EXTENDER IN GROUND BEEF PATTIES 1

Patties were formulated with 20% fat ground beef and sorghum flour (SF) at 2, 4, and 6% levels (10, 20, and 30% as rehydrated 1:4 with water). Beef patties containing SF had higher pH, greater yield, less total cooking loss, less shrinkage in diameter, and less increase in thickness than those without SF. Water activity of cooked patties was not affected by addition of SF. Fat and water retentions of beef patties increased as the level of SF increased. Hunterlab a values (redness) for raw patties decreased as the level of SF increased, but a values for cooked patties were not influenced by level of SF. Shear force and compression of cooked patties decreased as the level of SF increased. Meat aroma and flavor decreased, but sorghum aroma and flavor of cooked patties increased as the level of SF increased. Tenderness of cooked patties increased as the level of SF increased, but juiciness of cooked patties was not affected.     

Eating quality of low‐fat beef burgers containing fat‐replacing functional blends

Tapioca starch, carrageenan, oat fibre, pectin, whey protein and a commercial mixture of carrageenan and locust bean gum were assessed for their ability to mimic fat characteristics in cooked low‐fat (10%) beef burgers. Thirteen different blends of the ingredients were formulated in order to examine their effects on quality parameters of low‐fat beef burgers. The beef burgers were tested for cook yield, water‐holding capacity (WHC), retention of shape, sensory and mechanical texture analysis. Most blends significantly (P<0.05) increased both cook yield and WHC, in particular blends containing tapioca starch, oat fibre, whey protein and the carrageenan/locust bean gum mixture. These blends substantially reduced both Warner–Bratzler and Kramer shear values. Sensory analysis showed that beef burgers containing tapioca starch, oat fibre and whey protein were acceptable in terms of flavour and texture. The low‐fat control was found to be the toughest and driest of the beef burgers examined. This study shows that blends of these ingredients can be used to offset the poor quality associated with low‐fat beef burgers. © 1999 Society of Chemical Industry     

Replacement of Beef Fat with Partially Hydrogenated Plant Oil in Lean Ground Beef Patties

Partially hydrogenated plant oils (corn, cottonseed, palm, peanut and soybean) were substituted (in part) for beef fat in lean (10% fat) ground beef patties to improve nutrient content of ground beef. Effects of such addition on composition and consumer acceptability were evaluated. Addition of hydrogenated plant oils had little effect on composition of raw or cooked patties. Those containing hydrogenated corn or palm oil were not different (P>0.05) from all-beef patties in cooking loss or overall acceptability. Therefore substitution of hydrogenated oils for beef fat in production of lean ground beef patties may be feasible.     

FACTORS AFFECTING COLOR PROPERTIES OF BEEF PATTIES COOKED ON AN OUTDOOR GAS GRILL

Visual and instrumental color properties were obtained on beef patties cooked on an outdoor gas grill. Factors evaluated as to their influence on color were fat content, (20–28% vs 6–10%) patty handling prior to cooking (fresh, thawed either as patties or bulk ground beef), endpoint in cooking (57, 66, 71C, slit in outer edge of patty during cooking showing brown color), lighting conditions and evaluation time post-cooking. Factors resulting in less pink/red color and more brown color in cooked patties were (1) higher fat content, (2) cooking bulk frozen, thawed, then pattied product, (3) higher endpoint temperature and longer time postcooking before evaluation. Termination of cooking by observing brown color in slits in patties cooked on a gas grill was not synonymous with a safe internal temperature.     

Fat Level, High Temperature Cooking and Degree of Doneness Affect Sensory, Chemical and Physical Properties of Beef Patties

Ground beef patties containing either 4 or 20% fat were cooked by electric grill (G) alone or in combination with overhead broiler unit (BG) to be (visually) either medium or well-done. Patties with 20% fat had higher beef flavor intensity, juiciness and tenderness scores, lower Instron shear and compression values, and lower cooking yields than 4% fat patties. However, 4% fat patties cooked to medium, had similar sensory ratings to 20% fat patties cooked well-done. About 20% of patties cooked to medium did not reach recommended internal temperatures and holding times for food safety.     

Quality evaluation of beef patties formulated with bambara groundnut (Vigna subterranean L.) seed flour

This study evaluated composite beef–bambara groundnut (Vigna subterranean L.) seed flour patties to determine the effect of bambara groundnut flour (BGF) inclusion on the quality and acceptability of the products. The effect of different levels of BGF (0%, 2.5%, 5.0% and 7.5%) on the proximate composition and pH indicate that BGF had no significant (p ? 0.05) effect on moisture, protein and carbohydrate of raw patties except ash and pH whereas there was significant (p ? 0.05) effect on all the parameters for the cooked patties. BGF significantly (p ? 0.05) reduced the shrinkage of the cooked patties from 9.13% to 6.76%, while percentage cooking yield, moisture retention, and fat retention increased significantly (p ? 0.05) with increasing BGF levels from 79.1% to 87.2%, 67.51% to 78.05% and 73.51% to 88.34%, respectively. The use of BGF significantly (p ? 0.05) increased the pH of cooked patties from 6.16 to 6.23. Beef patties extended with BGF up to 5% addition exhibited good quality attributes most acceptable to the consumers. The pH of the 0% BGF–beef patties decreased significantly during storage, up to day 14, and increased thereafter. However, the pH of the patties with BGF consistently decreased significantly up to day 21. The TBA values of both (0% and 5% BGF–beef patties) increased significantly (p ? 0.05) from 0.054 to 0.25 and from 0.05 to 0.24 mg malonaldehyde/kg, respectively. All sensory attributes decreased significantly (p ? 0.05) as storage time progressed. The physico-chemical, microbiological and sensory characteristics of the patties were found to be acceptable after 21 days refrigerated storage.     

Glandless Cottonseed, Peanut and Soy Protein Ingredients in Ground Beef Patties: Effect on Rancidity and Othei Quality Factors

Defatted flours and protein concentrates and isolates produced from glandless cottonseed, peanut, and soybean were used in rehydrated state (1:2 dry material/water) to replace 10% of the meat in ground beef patties. Fat content of both all-beef and extended patties was adjusted to 20%. Patties were baked on racks to varying final internal temperatures. Extended patties were compared with all-beef patties for rancidity development, cooking properties, and sensory quality. All the oilseed protein ingredients retarded oxidative rancidity development in cooked refrigerated patties, with the highest antioxidant potential shown by the cottonseed protein ingredients. Extended patties had higher cooked yields than all-beef patties, contamed less fat, and were not significantly different from all-beef patties in sensory quality.     

ffect of Initial Fat Level and Cooking Method Cholesterol Content and Caloric Value of Ground Beef Patties

Ground beef patties were formulated to contain 0, 5, 10, 15, 20, 25 or 30% fat. The patties were either broiled or pan-fried for a predetermined time, then frozen. A sample from each treatment was thawed and reheated by a microwave oven and then refrozen. Fat, moisture, protein, ash, and cholesterol content, were determined for patties from each treatment. Cholesterol content of cooked patties was not related (P>0.05) to initial fat content. Caloric content of cooked patties was curvilinearly related to fat content of original (raw) patties due to the increased loss of fat during cooking as initial fat level increased.     

PROCESSING PARAMETER EFFECTS ON SENSORY AND INSTRUMENTAL TEXTURE CHARACTERISTICS OF REDUCED-FAT GROUND BEEF PATTIES

Effects of fat content (8 or 24%), processing temperature (–2, 1, 4C), plate size (2, 5, 5 mm), mixing time (3, 5, 8 min), and patty formation pressure (50, 100, or 150 kg) on characteristics of low-fat ground beef patties were evaluated. Reduced fat patties required less force to break when ground at –2C (2 mm plate) than when ground at 4C. Rubberiness increased as plate size increased. Rubbery scores were lowest at 4C/2 mm plate. Reduced-fat patties had lower cook losses. Increasing grinding temperature from –2 to 4C decreased break force, Kramer shear and cohesive texture. Break force was highest for patties mixed 8 min at –2C. Patty forming pressure affected breaking strength, cohesiveness, and cook loss. Production of reduced-fat ground beef patties by grinding through a 2mm plate at 4C, mixing for 2 min and forming patties at 150 kg pressure minimized rubbery texture and instrumental measures of patty hardness.     

Fatty Acid Composition and Caloric Value of Ground Beef Containing Low Levels of Fat

Ground beef patties containing five different levels of fat – 5, 10, 15, 20, and 25%– were cooked by boiling, browning, pan-frying, microwaving, roasting or broiling. Proximate composition, fat retention, energy content (kcal/100g), and fatty acid composition of raw and cooked patties were examined. Percentage fat retention decreased as fat content of the raw patty increased. Microwaving to “well done” and boiling resulted in ground beef with less fat than other methods of cooking at the higher fat levels. The proportion of fatty acids changed very little with increasing fat percentage and because of cooking method.     

蒸汽爆破对豆渣膳食纤维的影响及在韧性饼干中的应用

本文研究了蒸汽爆破(SE)处理对豆渣膳食纤维组成及含量的影响,以及添加汽爆豆渣对韧性饼干感官品质的影响。结果表明,汽爆处理对豆渣膳食纤维组成及含量有较大影响,随汽爆强度增加,豆渣可溶性膳食纤维(SDF)含量呈上升趋势,在1.5 MPa/30 s时达最大值36.28%;汽爆强度进一步增大,TDF和SDF含量都呈下降趋势。豆渣粉在韧性饼干中的添加量不宜超过5%,否则饼干品质下降明显;豆渣经汽爆处理后,其添加量增至10%,对饼干品质有较大改善。研究表明,适宜强度的汽爆处理可大幅提高豆渣中SDF含量,改善豆渣在韧性饼干中的添加应用效果,这为豆渣的开发利用提供了有效途径。