EFFECTS OF SOY CURD ON THE ACCEPTABILITY AND CHARACTERISTICS OF BEEF PATTIES

Soy curd-beef patties were made containing 0%, 5%, 10%, 20%, 75% and 100% (w/w) of curds which had been pressed at 300 psi, 600 psi and 1100 psi during manufacture. Taste panel tests showed that by increasing pressure on the soy curd or by the addition of flavoring to the curd before patty formation, increases in soy concentration became less detectable and the acceptability of the patties was drastically increased. Soy curd-beef patties made with 1100 psi curd and with color and flavor added were favorably accepted even at levels as high as 75% curd (w/w). The easy detectability of flavored soy in patties did not greatly change the high acceptability of the patties. The chemical composition, functional characteristics and physical properties of the soy-beef patties were also studied.     

EFFECT OF PROTEIN EXTENDERS ON FATTY ACIDS,CHOLESTEROL, SENSORY QUALITY AND COOKING LOSS OF BEEF PATTIES1

Ten different formulations of beef patties were processed to contain 20–50% fat from lean beef containing not more than 7% fat and beef fat consisting of not less than 90% fat and were extended with different levels of textured soy protein (TSP) at 5, 10 and 20% and single cell protein (SCP) at 2.5, 5 and 7.5%. The patties were stored at ?18°C for 6 months. Sensory quality evaluation showed that patties with 80% lean and 20% fat and patties with 40% lean, 40% fat and 20% TSP were the least acceptable, but lower levels of TSP and SCP addition were found to improve panel rating. A 17% increase in protein content and a reduction of about 13.5% in fat content was observed due to TSP and SCP incorporation. An average cooking loss in the different formulations was 33%, addition of protein extenders was found to reduce cooking loss by about 22% while fat loss averages 30.2%. A reduction of 21.1% of 18:1 and a reduction of approximately 18.7% of total FAME and 32% cholesterol were observed due to the addition of TSP and SCP.     

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.     

EFFECTS OF SOY PARTICLE SIZE AND COLOR ON THE SENSORY PROPERTIES OF GROUND BEEF PATTIES

A study was conducted to assess the effect of both size and color of textured soy protein particles on the visual and textural properties of extended (20% replacement) ground beef patties. A trained texture profile panel judged the hardness, cohesiveness, chewiness, moistness, and oiliness of nine different samples. In addition, judgments of the visual attributes of darkness, size of particles, and density of particles were made. Significant effects of soy ingredient were found for all judged attributes. It was concluded that soy ingredients having particle sizes smaller than the diameter of the openings of the grind plate used to process the meat/soy mixture produced the greatest change in the texture of the ground beef patties, because these particles passed through the grind plate unscathed, producing an easily discernable matrix of large meat particles and small soy particles. It was also concluded that carmel-colored soy ingredients produced less lightening of the cooked samples than uncolored soy ingredients.     

ACCEPTABILITY OF BEEF PATTIES EXTENDED WITH PORK AND/OR TEXTURED SOY PROTEIN1

Four beef or beef/pork ground meat blends were extended with textured soy protein (TSP) at 0, 10, 20 and 30% levels. Ground beef/pork/textured soy protein (TSP) patties with 30% TSP were rated lowest by consumers for raw color and appearance and overall cooked appearance. A beef (50%) and pork (30%) blend containing no TSP was rated highest by consumers for tenderness, flavor and overall desirability and higher by a trained sensory panel for flavor and overall desirability than blends containing TSP. Overall desirability ratings for visual and palatability characteristics of beef/pork meat patties were higher than for beef/pork/TSP blends. Results indicated a distinct advantage for palatability of the beef/pork blend as compared to beef/pork/TSP combinations.     

FREEZING OF RAW BEEF: INFLUENCE OF AGING, FREEZING RATE AND COOKING METHOD ON QUALITY AND YIELD

The combined effects of aging, freezing rate, frozen storage and cooking method on beef quality and yield were studied in a multifactorial experiment, using 1.5 cm slices of LD muscles from young steers. Aging for 2 wk resulted in significantly more tender, but slightly less juicy frozen meat than aging for 4 days. Prolonged frozen storage gave tougher meat and a larger tenderness difference between aging times. Freezing rates of 13, 2.0 and 0.04 cm/h differed but little in their effect on sensory quality, but slightly lower yield and redness value were noted for the lowest rate. Pan frying directly from the frozen state resulted in slightly higher juiciness and cooking yield, with larger differences in yield between freezing rates, than cooking after previous thawing. Significant interactions were noted for cooking method × freezing rate and for aging time × frozen storage time     

EFFECTS of THERMAL TREATMENTS ON TEXTURE of SOY PROTEIN ISOLATE TOFU

Effects of three thermal treatments; boiling at 100C and retorting at 110 and 121C, on texture of soy protein isolate tofu were studied for a range of heating times. Retorted tofu showed a shrinkage of 18–25% of its original size and a loss of 6–12% of its original moisture. Tofu processed at high temperatures and long heating times developed higher values of texture profile parameters than tofu processed at lower temperature and shorter heating times. the thermal treatment of tofu at elevated conditions also caused an increase in sensory hardness and a decrease in moistness and overall acceptability of the tofu. the increase in texture profile values appeared to be mirrored by a decrease in protein solubility in 1% sodium dodecyl sulfate solvent and a reduction in moisture content of the tofu. the formation of disulfides linkages at elevated temperatures and during heating at 100C stabilized protein aggregates that were initially formed by hydrophobic interactions. Formation of the disulfides and shrinkage of tofu as a result of moisture loss were suggested as the major reason for decreased sensory values of thermally processed soy protein isolate tofu.     

EFFECTS OF TOCOPHEROLS AND β-CAROTENE ON BEEF PATTIES OXIDATION

The effect of a tocopherol mixture (mainly composed of γ and Ø isomers) and β-carotene on lipid oxidation in cooked beef patties was studied. Ground beef was mixed with each or both compounds at designated concentrations. After mixing, cooking and storing at 4 ° 1C for 0, 2 and 5 days, the 2-thiobarbituric acid reactive substances (TBARS) and hexanal peak areas were determined. The results slowed that β-carotene had no antioxidant activity in this system. The tocopherol mixture at 200 ppm level slowed down the lipid oxidation by 56.7% for 2 days and 61% for 5 days of storage in cooked meat at 4 ° 1C, respectively.     

EFFECTS of FAT-SUBSTITUTES, FAT LEVELS and COOKING METHODS ON the QUALITY of BEEF PATTIES

Ground beef patties containing 2fat levels (5%, 10%), and 3 fat-substitutes (Lean-Bind (LB), Rice-Complete 3 (RC), Sta-Slim 171 (ST)) were processed using 3 cooking methods (microwave, roasting and pan-frying). Patties containing 20% fat, without fat-substitutes, were processed as a control. Textural properties of cooked patties were evaluated using Kramer shear, puncture, and Texture Profile Analyses. Press-juice, cooking losses and color parameters were also measured. Patties containing ST or LB and 10% fat, cooked by pan-flying, were more tender and juicier than other treatments including control, and had higher product yield than the control. ST provided the lowest cooking losses and the highest press-juice due to strong gelation ability and water holding capacity of ST Fat level did not affect color lightness (L*) or redness (a*) of the patties. However, both fat-substitute and cooking method affected L*, a* and b* (yellowness). Pan frying improved press-juice and reduced cooking losses, thus increased product yield, and provided tender patties compared to microwaved and roasted patties.