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Beef
Kinds of Beef Terms modified by Beef Selected AbstractsINFLUENCE OF PLATE TEMPERATURE AND MODE OF REHYDRATION ON TEXTURAL PARAMETERS OF PRECOOKED FREEZE-DRIED BEEFJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2003ANA MARIA IRENE BARTOLOMEU AYROSA The effects of various plate temperatures and rehydration procedures in texture of precooked freeze-dried beef, were evaluated. Frozen precooked commercial beef was freeze-dried at 20, 40, 60 and 80C during 24 h. The rehydration procedure involved two main variables: distilled water at room-temperature and at 80C, for 30 min. The texture profile analysis was performed with a TA-XT2 Texture Analyzer (SMS) for freeze-dried rehydrated samples and compared to frozen precooked beef. The results showed that with a same drying period, the 60C plate temperature and rehydrated in distilled water at room-temperature resulted in a better product texture, in regards to texture parameters hardness and chewiness. [source] MANUFACTURING FUNCTIONALITY OF CHILLED VENISON AND BEEFJOURNAL OF FOOD QUALITY, Issue 5 2007M.M. FAROUK ABSTRACT The functional properties of venison and beef semimembranosus muscle stored at ,1.5C for 4 weeks were compared. Sarcoplasmic protein solubility (SPS), malondialdehyde (MDA) and reactive sulfhydryl (SH) contents were higher in venison compared with beef (P < 0.001). Cooked batter torsion stress, tensile strength, rigidity and yield were higher in beef compared with venison (P < 0.01). Venison and beef did not differ in total protein solubility (TPS), emulsion activity index (EAI) and emulsion stability (ES) (P > 0.05). TPS, EAI, ES, MDA, torsion stress and strain, tensile strength and extensibility in meats from both species increased, and SPS and SH decreased with chilled storage time (P < 0.01). Within the parameters of this study, chilled beef had a better manufacturing functionality compared with venison. Manufacturing functionality in meats from both species improved with chill storage time, but the improvement was more marked in beef compared with venison. PRACTICAL APPLICATIONS The following are some of the practical applications of this research: (1) processing parameters used to optimize the manufacturing functionality of beef are not suitable for venison because the latter tenderize much faster than beef with negative implications to manufacturing functionality; (2) the current practice of not vacuum packaging frozen manufacturing meat will have a more deleterious effect on the functionality of venison compared with beef because of the higher rate of lipid oxidation in venison; and (3) the best time to use chilled venison and beef for maximum functionality is at 2 or 3 weeks of storage at ,1.5C. [source] EFFECT OF THAWING METHODS ON TEXTURAL QUALITY OF SOUS-VIDE STEWED BEEF ASSESSED BY SENSORY AND INSTRUMENTAL ANALYSESJOURNAL OF FOOD QUALITY, Issue 5 2001N.J.N. YAU ABSTRACT This study compared four different thawing methods using sensory test with magnitude estimation, preference test with hedonic scale and physical analyses. The four methods were tap-water, refrigeration, microwave reheating, and boiling-water reheating. For physical analyses, there were differences (p,0.001) among treatments in drip loss and expressible juice. For drip loss, the microwave reheated samples were the highest and the refrigeration and tap-water treated samples were the lowest. For expressible juice, tap-water and refrigerated samples were higher (p,0.01) than the microwave and boiling-water reheated samples. Microwave and boiling-water reheated samples had higher hardness and cheviness and lower juiciness and fiber-looseness. The refrigerated and tap-water thawed samples had reverse sensory properties. Naive panelists preferred the refrigerated and tap-water treated samples to the microwave and boiling-water reheated samples for juiciness, tenderness, and overall preference. Physical parameters from textural profile analysis were not different among the thawing methods. Expressible juice was the best indicator for sensory hardness, juiciness, fiber-looseness and chewiness among the physical parameters. Usually a quadratic regression model fit best when expressible juice was used to predict sensory textural properties. [source] IDENTIFICATION OF NONMEAT INGREDIENTS FOR INCREASING FAT HOLDING CAPACITY DURING HEATING OF GROUND BEEFJOURNAL OF FOOD QUALITY, Issue 4 2001E.T. ANDERSON ABSTRACT Eleven starch-, fiber-, and protein-based ingredients were evaluated for their fat holding capacity (FHC) in ground beef during heating. A test for FHC was developed where 20 g samples of 20% fat ground beef containing a 10% (wt/wt) addition of the selected ingredient were heated using low power microwave energy until internal temperatures were ,90C. Volumes of cooked-out water and fat were measured. FHC was determined based on the amount of fat released during cooking. High fiber ingredients retained more water and also had the highest FHC. Ground beef mixed with inner pea fiber retained the most fat, while the all-beef controls retained the least fat. Inner pea fiber appears to be a useful ingredient in the development of food products required to retain maximum amounts of fat during heating. [source] EFFECT OF SPICES ON GROWTH AND SURVIVAL OF SALMONELLA TYPHIMURIUM DT 104 IN GROUND BEEF STORED AT 4 AND 8CJOURNAL OF FOOD SAFETY, Issue 2 2006MILAGROS UHART ABSTRACT Few studies have addressed the use of spices against pathogens associated with meat. The effects of garlic, ginger and turmeric were evaluated against Salmonella Typhimurium DT 104 that were inoculated either in spice paste or in buffered peptone water (BPW) or in heat-treated ground beef and stored at 4 and 8C for 10 days. Data from the spice pastes study showed a decrease in Salmonella Typhimurium DT 104 counts, and the greatest reduction (3.39 log) was observed in garlic paste stored at 4C. Garlic in BPW data showed a reduction of 1.5 and 1.0 log in Salmonella Typhimurium counts at 4 and 8C, respectively. Ground beef stored at 4C showed no growth or a slight reduction in growth in samples with spice, while all samples at 8C showed an increase in Salmonella Typhimurium counts. Results show that the spices inhibit or inactivate Salmonella Typhimurium DT 104 when they are in direct contact. However, when spices are added to a complex food system such as ground beef, the inhibitory activity of these spices considerably decreases. [source] SIMULTANEOUS RECOVERY AND DETECTION OF FOUR HEAT-INJURED FOODBORNE PATHOGENS IN GROUND BEEF AND MILK BY A FOUR-COMPARTMENT THIN AGAR LAYER PLATEJOURNAL OF FOOD SAFETY, Issue 2 2006VIVIAN C.H. WU ABSTRACT A four-compartment thin agar layer (4-TAL) system was developed to improve operation efficiency and recover injured foodborne pathogens simultaneously. The system consisted of a layer of nonselective agar overlaid on four different selective agars (xylose lysine desoxycholate [XLD], cefsulodin irgasan novobiocin [CIN], modified Oxford medium [MOX] and MacConkey sorbitol agar [MSA]) housed in a four-compartment petri dish. We applied this system to simultaneously recover heat-injured (55C, 10 min) Escherichia coli O157:H7 (MSA), Listeria monocytogenes (MOX), Salmonella Typhimurium (XLD) and Yersinia enterocolitica (CIN) from ground beef and pasteurized milk. No significant difference (P > 0.05) occurred between the single recovery unit (nonselective agar overlaid on one selective agar in a standard petri dish) and the 4-TAL for detecting four heat-injured pathogens in tested samples. Both TAL methods showed greater recovery of four heat-injured pathogens than the pathogen-specific selective media (P < 0.05). The 4-TAL system appears to be efficient for recovery and detection of injured pathogens in food in terms of operation, material and labor costs, and space of incubation. [source] INACTIVATION OF BACTERIAL SPORES BY COMBINED ACTION OF HYDROSTATIC PRESSURE AND BACTERIOCINS IN ROAST BEEFJOURNAL OF FOOD SAFETY, Issue 4 2003N. KALCHAYANAND ABSTRACT Foodborne bacterial spores are normally resistant to high hydrostatic pressure; however, at moderate pressure, they can be induced to germinate and outgrow. At this stage, they can be killed by bacteriocin-based biopreservatives (BP-containing pediocin and nisin at 3:7 ratio; BPX, BP + 100 ,g/mL lysozyme; BPY, BPX+ 500 ,g/mL Na-EDTA). Based on this principle, spores of the meat spoilage organism, Clostridium laramie (1,2 × 102 spores/bag) alone or a mixture of four clostridial spores (5 × 103 spores/bag), Clostridium sporogenes, Clostridium perfringens, Clostridium tertium, and Clostridium laramie, were inoculated in roast beef in the presence of 5000 AU/g of bacteriocin-based biopreservatives. The roast beef samples were subjected to hydrostatic pressure (HP) at 345 MPa for 5 min at 60C and stored at 4 or 12C for 84 days or at 25C for 7 days. The HP treatment of roast beef samples inoculated with a mixture of clostridial spores could be stored for 42 days at 4C. The HP in combination with either BPX or BPY extended the shelf-life of roast beef up to 7 days at 25C. The combined treatment of HP and BP controlled the growth of C. laramie spores and extended the shelf-life of roast beef for 84 days when stored at 4C. [source] GROWTH KINETICS OF CLOSTRIDIUM PERFRINGENS IN COOKED BEEF,JOURNAL OF FOOD SAFETY, Issue 2 2003LIHAN HUANG ABSTRACT The objective of this work was to investigate the growth kinetics of a three-strain cocktail of Clostridium perfringens in cooked beef. The study was conducted by growing the heat-activated spores in ground beef under isothermal conditions between 17,50C. A four-parameter Gompertz equation was used as a primary model to fit the growth curves along with a modified Ratkowsky model to analyze the temperature dependence of the bacterial growth. Results indicated that the Gompertz model could accurately describe the growth of C. perfringens in cooked beef. The estimated theoretical minimum, optimum, and maximum growth temperatures of this organism in cooked beef were 9.8, 47.1, and 50.8C, respectively. A linear relationship between the durations of the lag and exponential phases of growth curves was observed in this study. Such a linear relationship can be used to generate a linear isothermal growth curve complete with the lag, exponential, and stationary phases without complex mathematical computation. The kinetic models and growth parameters obtained from this study potentially can be applied to the food industry to design appropriate cooling schedules and estimate the growth of C. perfringens in thermally processed beef products under temperature abuse conditions. [source] CONSUMER PREFERENCES FOR PATHOGEN-REDUCING TECHNOLOGIES IN BEEF,JOURNAL OF FOOD SAFETY, Issue 2 2001KRISTA FINGERHUT ABSTRACT Two surveys were conducted by mail to evaluate consumers' preferences for beef treated by the steam and hot-water pasteurization technologies, in a comparison with beef treated by irradiation and nontechnology treated "regular" beef. More than 64% of the respondents reported that they preferred ground beef treated by irradiation to that treated by the two pathogen-reducing technologies. More than 87% of the respondents stated that they preferred ground beef treated by the two technologies to nontechnology treated beef. Sixty percent of the respondents reported that they were willing to pay for beef treated by the two pathogen-reducing technologies with an averaged willingness-to-pay of 0.36/lb over nontechnology treated beef. Compared with their counterparts; women, those having a better self-reported health status, and those with children at home (, 18 years of age) were more likely to report a preference for beef treated by the two heat-related pasteurization technologies. The income level of the respondents was negatively associated with their preference for beef treated by the two heat-related pasteurization technologies. The strong consumer preference coupled with willingness-to-pay for beef treated by the two pathogen-reducing technologies, suggest that consumers are willing to bear the cost of using these technologies if beef packers would invest in such technologies as a means of improving the quality of their products. [source] EFFECT OF LACTIC ACID AND LACTIC ACID BACTERIA TREATMENT ON MYOFIBRILLAR PROTEIN DEGRADATION AND DYNAMIC RHEOLOGY OF BEEFJOURNAL OF TEXTURE STUDIES, Issue 3 2007M. SIGNORINI ABSTRACT Lactic acid has been used as an efficient decontaminant in meats aimed for direct consumption or product fabrication. However, reports on the functionality of proteins extracted from lactic acid-treated meat are scattered. The objective of this work was to study the degradation and gelling ability of myofibrillar protein extracts obtained from beef treated with lactic acid of chemical and microbial origins, stored at 4 and 20C. The gelling ability was considerably reduced by lactic acid treatment as a result of protein denaturation in acid conditions at both storage temperatures. Scanning electron microscopy showed loose structures resulting in low penetration resistance and storage modulus. Treatments with lactic acid or lactic acid bacteria (LAB) had similar effect on tan,, affecting gel rigidity but not elasticity. Penetration in gels obtained from LAB-treated meat was highly correlated with myosin degradation. Lactobacillus carnis -treated meat produced compact gels with high penetration resistance and storage modulus, although the structure became looser with storage time. LAB treatment, although not as efficient as lactic acid as a meat preservative, is a milder process causing less severe changes in meat structure rheology. PRACTICAL APPLICATIONS The potential of lactic fermentation by selected strains is somewhat limited as compared to lactic acid preservation of meat substrates, regarding pH reduction and its consequence on pathogens and spoilage microorganism population reduction. However, lactic acid bacteria (LAB) treatments are milder; therefore, changes in protein structure and rheology are less severe. Lactic acid in its chemical form promotes protein changes, whereas LAB does not. As myofibrillar protein configuration is responsible for most meat functional properties, such as gel and emulsion formation, it is important that protein structure remains unchanged as much as possible. Using nonproteolytic strains, protein degradation can only be altered by endogenous or bacteria-produced enzymes, which can be inhibited by several means. Meat preservation by lactic fermentation with selected strains can be an alternative when keeping meat protein functional properties unaltered. [source] Fat Content Influences the Color, Lipid Oxidation, and Volatiles of Irradiated Ground BeefJOURNAL OF FOOD SCIENCE, Issue 6 2009H.A. Ismail ABSTRACT:, Ground beef with 10%, 15%, or 20% fat were added with none, 0.05% ascorbic acid + 0.01%,-tocopherol, or 0.05% ascorbic acid + 0.01%,-tocopherol + 0.01% sesamol, and irradiated at 0 or 2.5 kGy. The meat samples were displayed under fluorescent light for 14 d at 4 °C. Color, lipid oxidation, volatiles, oxidation-reduction potential (ORP), and carbon monoxide (CO) production were determined during storage. Irradiation increased lipid oxidation and total volatiles of ground beef regardless of fat contents. Ascorbic acid +,-tocopherol + sesamol treatment was the most effective in reducing lipid oxidation during storage. The production of ethanol in nonirradiated ground beef increased dramatically after 7 d of storage due to microbial growth. Total aldehydes and hexanal increased drastically in irradiated control over the storage period, but hexanal increased the most by irradiation.,L*-values was decreased by irradiation, but increased in all meat regardless of fat contents as storage period increased. Irradiation reduced the redness, but fat contents had no effect on the,a*-value of ground beef. Sesamol lowered, but ascorbic acid +,-tocopherol maintained the redness of irradiated beef up to 2 wk of storage. The yellowness of meat was significantly decreased by irradiation. The reducing power of ascorbic acid +,-tocopherol lasted for 3 d, after which ORP values increased. Irradiation increased CO production regardless of fat content in ground beef. In conclusion, up to 20% fat had no effect on the quality change of irradiated ground beef if ascorbic acid +,-tocopherol was added. [source] Modeling the Effect of Marination and Temperature on Salmonella Inactivation during Drying of Beef JerkyJOURNAL OF FOOD SCIENCE, Issue 4 2009Yohan Yoon ABSTRACT:, This study modeled the effect of drying temperature in combination with predrying marination treatments to inactivate Salmonella on beef jerky. Beef inside round slices were inoculated with Salmonella and treated with (1) nothing (C), (2) traditional marinade (M), or (3) dipped into a 5% acetic acid solution for 10 min before exposure to M (AM). After 24 h of marination at 4 °C, samples were dehydrated at 52, 57, or 63 °C. Total counts (tryptic soy agar supplemented with 0.1% sodium pyruvate, TSAP) and Salmonella (XLD agar) were enumerated after inoculation and at 0, 2, 4, 6, 8, and 10 h during drying. For calculation of death rates (DR, log CFU/cm2/h), shoulder period (h), low asymptote, and upper asymptote, cell counts from TSAP were fitted to the Baranyi model. The DRs were then further expressed as a function of storage temperature. Inactivation occurred without an initial lag phase (shoulder period), while correlation (R2) values of fitted curves were , 0.861. The DRs of C (,0.29 to ,0.62) and M (,0.36 to ,0.63) treatments were similar, while DRs of the AM treatment were higher (,1.22 to ,1.46). The DRs were then fitted to a polynomial equation as a function of temperature. After validation, good (C and M) or acceptable (AM) model performances were observed (R2= 0.954 to 0.987; bias factors: 1.03 [C], 1.01 [M], 0.71 [AM]; accuracy factors: 1.05 [C], 1.06 [M], 1.41 [AM]). The developed models may be useful in selecting drying temperatures and times in combination with predrying treatments for adequate inactivation of Salmonella in beef jerky. [source] Effect of Actinidin on the Protein Solubility, Water Holding Capacity, Texture, Electrophoretic Pattern of Beef, and on the Quality Attributes of a Sausage ProductJOURNAL OF FOOD SCIENCE, Issue 3 2009M. Aminlari ABSTRACT:, The objective of this study was to study the effect of actinidin, a sulfhydryl protease from kiwi fruit, on the protein solubility (nitrogen solubility index [NSI]), water holding capacity (WHC), texture, and SDS,PAGE pattern of beef and to evaluate the effect of pretreatment of beef with actinidin on the quality attributes of a sausage product. Actinidin was partially purified by precipitation with ammonium sulfate, followed by DEAE-Sephadex column chromatography. Actinidin significantly (P < 0.05) increased NSI and WHC of beef; the highest NSI and WHC (approximately 20% and 8% increase, respectively) was observed when beef was incubated with 0.9 unit enzyme/g beef. Texture analysis indicated increased tenderization (10% decrease in shear force) when slices of cattle beef were treated with actinidin at 37 °C for 2 h. SDS,PAGE results indicated appearance of several low molecular weight bands (<10 kDa) after treating beef with different levels of actinidin for 30 or 60 min. Slight changes in protein band in the range of 100 to 120 kDa and 13 to 25 kDa were also observed. Use of actinidin-tenderized beef significantly improved emulsion stability, texture, and organoleptic properties of the sausage product. [source] Chitosan Protects Cooked Ground Beef and Turkey Against Clostridium perfringens Spores During ChillingJOURNAL OF FOOD SCIENCE, Issue 6 2006Vijay K. Juneja ABSTRACT:, We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by the biopolymer chitosan during abusive chilling of cooked ground beef (25% fat) and turkey (7% fat) obtained from a retail store. Chitosan was mixed into the thawed beef or turkey at concentrations of 0.5%, 1.0%, 2.0%, or 3.0% (w/w) along with a heat-activated 3-strain spore cocktail to obtain a final spore concentration of 2 to 3 log10 CFU/g. Samples (5 g) of the ground beef or turkey mixtures were then vacuum-packaged and cooked to 60 °C in 1 h in a temperature-controlled water bath. Thereafter, the products were cooled from 54.4 to 7.2 °C in 12, 15, 18, or 21 h, resulting in 4.21, 4.51, 5.03, and 4.70 log10 CFU/g increases, respectively, in C. perfringens populations in the ground beef control samples without chitosan. The corresponding increases for ground turkey were 5.27, 4.52, 5.11, and 5.38 log10 CFU/g. Addition of chitosan to beef or turkey resulted in concentration- and time-dependent inhibition in the C. perfringens spore germination and outgrowth. At 3%, chitosan reduced by 4 to 5 log10 CFU/g C. perfringens spore germination and outgrowth (P, 0.05) during exponential cooling of the cooked beef or turkey in 12, 15, or 18 h. The reduction was significantly lower (P < 0.05) at a chilling time of 21 h, about 2 log10 CFU/g, that is, 7.56 log10 CFU/g (unsupplemented) compared with 5.59 log10 CFU/g (3% chitosan). The results suggest that incorporation of 3% chitosan into ground beef or turkey may reduce the potential risk of C. perfringens spore germination and outgrowth during abusive cooling from 54.4 to 7.2 °C in 12, 15, or 18 h. [source] Evaluation of Garam Masala Spices and Phosphates as Antioxidants in Cooked Ground BeefJOURNAL OF FOOD SCIENCE, Issue 5 2006Mihir N. Vasavada ABSTRACT:, This study determined antioxidant effects and sensory attributes of individual ingredients (black pepper, caraway, cardamom, chili powder, cinnamon, cloves, coriander, cumin, fennel, ginger, nutmeg, salt, star anise) of an Indian spice blend (garam masala) in cooked ground beef. Thiobarbituric acid (TBA) values were measured as an indicator of rancidity for cooked samples on 1-, 8-, or 15-d refrigerated storage. Cooked samples were evaluated by a trained panel (n= 13) for the intensity of rancid odor/flavor, beef flavor, and spice flavor and correlated with TBA values of same day samples. We also investigated possible additive effects between spice antioxidants and iron binding (type II) antioxidants on lipid oxidation by measuring TBA values. All spices had antioxidant effects on cooked ground beef, compared to controls. Among spices, cloves were the most effective in controlling lipid oxidation, with TBA values of 0.75, after 15-d refrigerated storage. All spices at their recommended levels lowered rancid odor and flavor in cooked ground beef, compared to controls. As expected, most spices also imparted distinctive flavors to cooked ground beef. There was a positive correlation (0.77) between TBA values on 15-d refrigerated storage and rancid odor/flavor. Type II antioxidants (iron-binding phosphate compounds) were more effective than individual type I antioxidants (spices and butylated hydroxytoluene; BHT) for maintenance of low TBA values in cooked ground beef during storage. Additive effects were observed with rosemary + milk mineral or sodium tripolyphosphate (STP) compared to rosemary alone. [source] Evaluation of Antioxidant Effects of Raisin Paste in Cooked Ground Beef, Pork, and ChickenJOURNAL OF FOOD SCIENCE, Issue 4 2006M.N. Vasavada ABSTRACT:, The objective of this study was to evaluate the possible antioxidant activity of raisin paste added to raw ground beef, pork, or chicken before cooking to 163 °C. Samples were held at 2 °C for up to 14 d. TBA values were measured using a distillation method, to avoid yellow color interference found in "wet" TBA methods. Sample meat flavor intensity, rancid flavor intensity, and raisin flavor intensity were evaluated by a trained panel (n = 6). Addition of raisin paste lowered (p < 0.05) TBA values and decreased panel scores for rancid flavor scores of all meat samples in a concentration-dependent manner. Highest antioxidant effects were obtained with a minimum of 1.5%, 2.0%, or 2.0% raisin paste in cooked ground beef, pork, or chicken, respectively. There was a high correlation (0.93, 0.94, 0.94) between TBA values and sensory rancid flavor scores in beef, pork, and chicken samples respectively. Addition of a reducing sugar (glucose) was nearly as effective as raisins for maintenance of low TBA values and rancid flavor scores, probably due to antioxidant effects of Maillard browning products. There was no detectable raisin flavor in cooked ground beef samples with added raisins. However, all meats with added glucose had a higher raisin flavor intensity score than controls, indicating that panelists associated sweetness with raisin flavor. Maillard browning (sample darkening) was evident after cooking of ground chicken with either raisins or glucose. [source] Mortadella Sausage Formulations with Partial and Total Replacement of Beef and Pork Backfat with Mechanically Separated Meat from Spent Layer HensJOURNAL OF FOOD SCIENCE, Issue 3 2005Marco A. Trindade ABSTRACT: Mortadella sausages were formulated with 0%, 20%, 40%, 60%, 80%, and 100% mechanically separated layer hen meat (MSLM) replacing the beef and pork backfat as raw materials. Treatments were compared by determination of shear force, sensory acceptance, and stability during cold storage (microbial analysis, thiobarbituric acid-reactive substances [TBARS], color, and descriptive sensory analysis). Mortadella with higher MSLM presented lower shear force values. TBARS index and sensory rancidity were not affected. The greater the amounts of MSLM used, the paler was the pink color observed in the sensory evaluations and the lower were the CIE a* values. All treatments presented minimal increase in the microbiological counts evaluated during storage. The limiting factor in the acceptance of the product was the perception of bone particles in mortadella containing 60% or more MSLM. [source] Empirical Distribution Models for Escherichia coli 57:H7 in Ground Beef Produced by a Mid-size Commercial GrinderJOURNAL OF FOOD SCIENCE, Issue 5 2004R.A. Flores ABSTRACT: The purpose of this research was to develop empirical models that describe the amount and distribution of ground beef contaminated with Escherichia coli O157:H7 when a contaminated beef trim is introduced into a batch of uncontaminated beef before processing in a mid-size commercial grinder (34 g/s). A beef trim was inoculated with a rifampacin-resistant strain of E. coli O157:H7 and added to a batch of noncontaminated trims at the grinding step. To study the distribution of the E. coli O157:H7rif in the ground beef, 6 treatments with different inoculum levels (1 to 6 log10 colony-forming units [CFU]) were tested. Removal or pick up of the residual contamination with E. coli O157:H7rif left in the grinder was evaluated. E. coli O157:H7rif was detected in 9% to 86% of the total ground beef for the 1 to 6 log10 CFU inoculum levels, respectively. E. coli O157:H7rif contamination was detected in the collar that fixes the grinder's die and blade to the hub. An exponential algorithm described the relationship between the quantities of ground beef containing E. coli O157:H7rif and the inoculum level (R2= 0.82). Distribution models based on a Chi-squared algorithm were developed for each inoculum level describing the contamination level as a function of the batch fraction processed (R2= 0.81 to 0.99). The results of this study corroborate that when beef processors test for pathogenic contamination in a mid-scale grinder, they should test the beef residues in the collar that fixes the grinder's die and blade to the hub. [source] Relationship Between Fragmentation of Myofibrils and Liberation of Phospholipids from Z-Disks Induced by Calcium Ions at 0.1 mM: Mechanism of Tenderization of Pork and Beef during Postmortem AgingJOURNAL OF FOOD SCIENCE, Issue 9 2003K. SHIMADA ABSTRACT We studied the myofibril fragmentation using porcine and bovine myofibrils to determine the mechanism by which myofibrils are fragmented during postmortem aging of meat. Both myofibril fragmentation and liberation of phospholipids from Z-disks were maximally induced by calcium ions at 0.1 mM. These phenomena showed identical dependencies on pH and temperature in the presence of calcium ions at 0.1 mM. All phospholipids in Z-disks, except for lysophosphatidylethanolamine, had affinity for calcium ions. Therefore, we concluded that liberation of calcium-phospholipid compounds from Z-disks causes weakening of the Z-disk structure, resulting in the myofibril fragmentation during postmortem aging of meat. [source] Warmed-Over Flavor and Lipid Stability of Beef: Effects of Prior NutritionJOURNAL OF FOOD SCIENCE, Issue 9 2002A. Yang ABSTRACT: Development of lipid oxidation and warmed-over flavor (WOF) in cooked meats during refrigerated storage was investigated in beef from pasture-fed cattle or grain-fed cattle supplemented with 0, 500, or 2500 IU vitamin E/head/d for 105 d. Meat from pasture-fed cattle contained as much ,-tocopherol as grain-fed cattle supplemented with 2500 IU vitamin E, but it was found to be less prone to lipid oxidation and development of WOF. It also contained a higher percentage of linolenic acid and lower content of linoleic acid than grain-fed beef. [source] Pasture and Grain Finishing Affect the Color Stability of BeefJOURNAL OF FOOD SCIENCE, Issue 7 2002M.C. Lanari ABSTRACT: We determined the effect of pasture feeding (P0) or sorghum feeding with 2500 IU/head/d; (G2500) or without (G0) vitamin E supplementation on the color stability of gluteus medius (GM), longissimus lumborum (LL) and semimembranosus (SM). Diets did not affect the total pigment concentration of the muscle. Color stabilities were G2500 > P0 > G0 for fresh GM and SM and G2500 > G0 > P0 for fresh LL. Color stabilities of aged beef from the P0 and G2500 treatments were similar and higher than those from unsupplemented animals. Color stability of minced beef ranked as: P0 aged > G0 and G2500 fresh > P0 fresh > G0 and G2500 aged. [source] Antioxidant Properties of Natural Plant Extracts Containing Polyphenolic Compounds in Cooked Ground BeefJOURNAL OF FOOD SCIENCE, Issue 4 2002J. Ahn ABSTRACT Thiobarbituric acid-reactive substances (TBARS) values, hexanal content, and sensory analysis were used to evaluate the effectiveness of selected natural antioxidants to reduce warmed-over flavor (WOF) development in cooked ground beef. The control without added antioxidant showed the highest TBARS value, hexanal content, and WOF scores. Grape seed extract (ActiVinTM) and pine bark extract (Pycnogenol®) significantly improved the oxidative stability of cooked beef. Compared to the control, ActiVinTM, Pycnogenol®, and oleoresin rosemary reduced the hexanal content by 97%, 94% and 73% after 3 d of refrigerated storage, respectively. WOF scores showed a similar pattern as TBARS values and hexanal contents. TBARS values, WOF scores, and hexanal contents were all well correlated. [source] Volatile Compounds of Raw Beef from 5 Local Spanish Cattle Breeds Stored Under Modified AtmosphereJOURNAL OF FOOD SCIENCE, Issue 4 2002K. Insausti ABSTRACT Volatile compounds of raw beef from Asturiana de los Valles, Morucha, Parda Alpina, Pirenaica, and Retinta cattle breeds were studied. Steaks were packaged under 60% O2, 30% CO2, and 10% N2, and 53 volatile compounds were tentatively identified by purge-and-trap extraction and gas chromatography with mass spectrometry after 0, 5, 10, and 15 d of chill storage. The degradation of beef quality with increasing storage time was evidenced by the increase in 2,3,3-trimethylpentane, 2,2,5-trimethylhexane, 3-octene, 3-methyl-2-heptene, 2-octene, and 2-propanone and by the decrease in dimethyl sulfide. Consequently, some of the volatile compounds, which are believed to be formed by thermal degradation of meat, might be formed during chill storage, and the rate of formation of some was dependent on the specific compound. [source] Effect of Aging Time on Volatile Compounds, Odor, and Flavor of Cooked Beef from Pirenaica and Friesian Bulls and HeifersJOURNAL OF FOOD SCIENCE, Issue 3 2002C. Gorraiz ABSTRACT: Volatile compounds, odor, and flavor produced by beef from bulls and heifers of the Pirenaica and Friesian breeds were studied during 7 d of aging. The Friesian breed beef had stronger fatty flavor and aftertaste than the Pirenaica, as well as differences in the content of several volatile compounds. Bull beef had stronger liver-like odor and flavor, and bloody flavor that were related to a higher 2-propanone content, while beef from heifers had stronger characteristic flavor. Aging of meat increased characteristic flavor and aftertaste. Ethanal showed a positive correlation with livery flavor and a negative correlation with the characteristic odor. The hexane seems to contribute to fatty flavor, 2-propanone was related to livery and bloody notes, and 2,2,4,6,6-pentamethylheptane to characteristic flavor. [source] Tenderization of Heated Sliced Beef by Succinylated Glycerol Monostearate, a Novel Meat TenderizerJOURNAL OF FOOD SCIENCE, Issue 4 2001K. Mori ABSTRACT Succinylated glycerol monostearate (SGMS) was most effective in reducing shear-force value when used as a surfactant to tenderize meat using sheep casings as a model of intramuscular connective tissue. Roasted beef slices that had been treated with 2% granular SGMS showed a marked decrease in toughness due to the penetration of SGMS along the perimysium during heating. Collagen fibrils in the perimysium were transformed into a sheet-like structure that seemed very likely to be a complex of SGMS and thermally denatured collagen. These structural changes could account for the tenderness of the roasted beef slices. [source] Prevention of Transient Discoloration of BeefJOURNAL OF FOOD SCIENCE, Issue 3 2001G. Tewari ABSTRACT Oxygen absorbent technology in conjunction with controlled atmosphere packaging(CAP) was used to prevent transient discoloration in master-packaged beef steaks. Two types of commercial O2 scavengers were used in the study. The master packs were stored at 1± 0.5 °C. The steaks from master packs were presented in a display-case for visual evaluation. Reflectance spectra from each steak-surface were obtained to estimate metmyoglobin content. Steaks packaged without O2 scavengers showed more discoloration, and had significantly higher proportions of metmyoglobin when compared to steaks with O2 scavengers, after most storage intervals (p < 0.05). Prevention of metmyoglobin formation was influenced by the number but not the type of O2 scavenger employed (p > 0.05). Keywords: oxygen scavengers, centralized meat operations, transient discoloration [source] Application of agglomerative hierarchical clustering to identify consumer tomato preferences: influence of physicochemical and sensory characteristics on consumer responseJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2006Marta Serrano-Megías Abstract A multiple regression model was developed to predict the acceptability of the four tomato varieties studied (Aranka, Cherry, Beef and Pitenza). Agglomerative hierarchical clustering showed the presence of four consumer clusters. One cluster preferred small tomatoes (Aranka and Cherry) and another cluster the larger tomatoes (Beef and Pitenza). In the sensorial analysis Aranka was the preferred variety, scoring more highly in taste, odour, acidity, sweetness and hardness. In the physicochemical analysis Aranka also obtained the highest values for titratable acidity (TA) and sugars (SSC), confirming that these parameters are important in tomato flavour. Lower values for both sets of parameters were reflected by lower consumer acceptability, with Beef and Pitenza receiving the lowest score for these flavours attributes (except odour). A significant correlation between the sensorial and physicochemical parameters was also observed: odour was positively correlated with calibre, while taste, acidity, hardness and acceptability were negatively correlated with calibre, pH and SSC/TA and positively correlated with SSC and TA. Copyright © 2005 Society of Chemical Industry [source] Optimal Generic Advertising with a Rationed Related Good: The Case of Canadian Beef and Chicken MarketsCANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2002J. A. L. Cranfield An optimal advertising rule is derived for a good sold in an open market (beef) when a related substitute good (chicken) is production rationed and whose imports are subject to trade restrictions. Such a rule is developed using a multi-market equilibrium displacement model that reflects demand interrelatedness, open trade of the advertised good (beef), with rationed production and restricted trade of the related good (chicken). The optimal rule nests earlier optimal advertising rules under a variety of conditions. Results underscore the importance of accounting for cross-product advertising effects. When these effects are present (absent), the optimal generic beef advertising intensity in Canada is shown to fall (rise) with elimination of supply management in Canada's chicken sector. L'auteur dérive une règie sur l'optimisation de la publicité pour un produit vendu sur un marché libre (b,uf) en présence d'un produit de substitution rationné dont on restreint les importations. Pour parvenir à une telle règie, l'auteur a utilisé un modèle de déplacement du point d'équilibre sur un marché multiple illustrant les liens entre la demande des produits concernés, le libre-échange du produit faisant l'objet de la publicité (b,uf) et la restriction de la production et des importations du produit apparenté (poulet). La règie d'optimisation englobe les règles antérieures sur l'optimisation de la publicité dans diverses situations. Les résultats soulignent qu'il est important de prendre en compte les retombées de la publicité sur les autres produits. Au Canada, en présence (absence) de telles retombées, le degré optimal de publicité générique sur le b,uf diminue (augmente) avec l'abolition de la gestion de l'offre de poulet. [source] INJUSTICE AND IRRATIONALITY IN CONTEMPORARY YOUTH POLICYCRIMINOLOGY AND PUBLIC POLICY, Issue 4 2004DONNA M. BISHOP Lionel Tate was 12 years old when he killed 6-year-old Tiffany Eunick. Tiffany had been staying at the Tate home and, by all accounts, got along well with Lionel. The two were playing at "wrestling" when Lionel decided to try out some moves that he had seen on television. He threw Tiffany across the room, inflicting fatal injuries. Despite the boy's tender age, the prosecutor transferred Lionel to criminal court on a charge of first-degree murder, an offense carrying a mandatory penalty of life without parole. The boy was given an opportunity to plead guilty to second-degree murder in return for a sentence of three years incarceration, but he rejected the offer. A jury subsequently convicted him of first-degree murder. At sentencing, the prosecution recommended leniency, which drew an angry response from the judge: If the state believed the boy did not deserve to be sent to prison for life, why hadn't it charged him with a lesser offense? Without any inquiry into the boy's cognitive, emotional, or moral maturity, the judge imposed the mandatory sentence.1 Raymond Gardner was 16 years old when he shot and killed 20-year-old Mack Robinson.2 Raymond lived in a violent urban neighborhood with his mother, who kept close watch over him. He had no prior record. He was an A student and worked part-time in a clothing store to earn money for college. On the day of the shooting, a friend came into the store to tell Raymond that Mack had a beef with him about talking to a girl, and was "looking to get him." The victim was known on the street as "Mack the Knife" because he always carried a small machete and was believed to have stabbed several people. To protect himself on the way home, Raymond took the gun kept under the counter of the shop where he worked. As he neared home, Mack and two other men approached and blocked his path. According to eyewitness testimony, Raymond began shaking, then pulled out the gun and fired. Mack ran into the street and fell. Raymond followed and fired five more shots into the victim's back as he lay dying on the ground. Raymond did not run. He just stood there crying. The prosecutor filed a motion in juvenile court to transfer Raymond on a charge of first-degree murder. The judge ordered a psychological evaluation, which addressed the boy's family and social background, medical and behavioral history, intelligence, maturity, potential for future violence and prospects for treatment. The judge subsequently denied the transfer motion. He found Raymond delinquent and committed him to a private psychiatric treatment facility.3 [source] Effects of crowding on populations of Aedes albifasciatus larvae under laboratory conditionsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2000Raquel M. Gleiser Abstract Aedes (Ochlerotatus) albifasciatus (Macquart 1838) (Diptera: Culicidae) is a neotropical flood water mosquito, incriminated as the main vector of the western equine encephalitis virus, and which affects beef and milk production in central Argentina. The short time required to hatch and develop from egg to adult, usually in temporary pools, suggests a strategy which allows for exploitation of transient pools, thus evading predation and interspecific competition. Under these conditions intra specific competition could represent a major density-dependent source of larval mortality, but the relative importance of density-dependent regulation of mosquito populations has generated controversy. Therefore we examined the effects of larval density on basic population characteristics of Ae. albifasciatus in the laboratory. Larvae were obtained by synchronous hatching of eggs laid by field-trapped females. Emerging larvae (L1) were used to build cohorts of different initial densities, kept in plastic trays with 400 ml of distilled water, and food supplied daily during the first 10 days (0.1 g per larvae day,1). Age-specific development time and specific and relative mortality were estimated, and their relation to initial larval density was assessed through linear and non-linear regressions and correlation analysis. First hatching was registered 3 h after flooding the eggs. Higher levels of pre-adult mortality were detected in groups with higher densities. Specific mortality and average time to enter a stage of L1 to L3 could directly be related to initial larval density, but no significant relations were found for L4 and pupae. Results suggest that crowding could be a factor capable of regulating the density of natural populations of Ae. albifasciatus. [source] | ||||||||||||||||||||||