Counts In Meat Research Articles

Effects of cobalt-sourced γ-irradiation on the meat quality and storage stability of crayfishes (Procambarus clarkii)

This study aimed to explore the influences of cobalt-sourced irradiation on the meat quality and storage stability of Procambarus clarkii. Pieces of tail meat of P. clarkii were processed, boiled, and packed in transparentretort pouchs and then exposed to 60Co-γ-ray (0, 1.25, 3.32, 5.30, and 7.24 kGy). Changes in meat indices such as pH, total plate count, and total volatile base-nitrogen (TVB-N), texture properties, were investigated. After irradiation at the optimum irradiation dose, crayfish meats was stored at 0, 4 and 8 °C respectively, samples were collected for determinations at 0, 3, 6, 9 and 12 days. With increased irradiation dose, the total plate count in meat significantly decreased, whereas TVB-N greatly increased (P < 0.05). The irradiation dose of 3.32 kGy can realize both sterilization effect and maintain the quality of crayfish meat to the maximum extent. Total plate count and TVB-N in crayfish meat slowly grew at a storage temperature of 0 °C, their contents reached or approached the edible threshold by 9th day of storage, thereby prolonging the shelf life to 9d. Research demonstrates that 3.32 kGy cobalt-sourced irradiation and 0 °C storage can provide some bacteriostasis to some extent and prolong the shelf life of boiled crayfish.

Improving the lipid oxidation of beef patties by plasma-modified essential oil/protein edible composite films

To regulate the lipid oxidation of meat induced by plasma treatment, this study combined plasma with essential oil/protein edible composite films. Effects of plasma on the physicochemical properties of the composite film, such as color, swelling rate, solubility, transmittance, water vapor permeability, and chemical bonds, were evaluated. Changes in basic physicochemical properties and volatile compounds of fresh beef patties coated with composite films after plasma treatment were evaluated. Results showed that plasma treatment had no significant effect on the physicochemical properties of films (p > 0.05). Plasma treatment could accelerate the penetration of essential oil into meat and improve the sterilization efficiency, the total bacterial count in meat decreased from 4.66 to 3.75 log CFU/g (p < 0.05). Meanwhile, composite films could significantly reduce the plasma-induced lipid oxidation from 0.16 to 0.06 mg MDA/kg (p < 0.05), and decrease the existence of 10 volatile compounds (including alcohols, aldehydes, ketones, and esters) in beef patties after plasma treatment. In general, the application of plasma combined with composite films in the preservation of fresh meat has a good application prospect.

Impact of probiotics and/or organic acids supplementation on growth performance, microbiota, antioxidative status, and immune response of broilers

The objective of the present study is to examine the effects of probiotics, organic acids, and their combination on growth performance, carcase characteristics, blood biochemical parameters, antioxidative status, immune responsiveness, and bacterial count in broilers. A total of 1,200 1-d-old unsexed broiler chicks (Ross 308) were randomly assigned in a completely randomised design according to a 2 × 3 factorial arrangement, with 2 levels of dietary probiotics (0% and 0.2%) possessing 4 × 109 cfu/g of Bacillus subtilis and Bacillus licheniformis and 3 levels (0, 0.03, and 0.06%) of organic acids blend of acetic and propionic acids for a total of 6 experimental treatments with 10 replicates each (20 birds/replicate). Dietary 0.02% probiotics increased final body weight. Addition of probiotics or organic acids increased plasma total protein concentration significantly. Dietary 0.02% probiotics increased plasma glutathione peroxidase (GSH-Px) concentration and enhanced humoral- and cell-mediated immune response. Supplementation of 0.03% and 0.06% organic acids improved cell-mediated immune response significantly. Interestingly, addition of probiotics and/or organic acids reduced total bacterial count in breast meat, and Salmonella was not detected in meat. A significant interaction between probiotics and organic acids was observed in plasma globulin concentration, plasma GSH-Px concentration, cell-mediated immune response at 24 h post-phytohaemagglutinin-P injection, intestinal Salmonella count, and total bacterial count in meat. It could be concluded that the inclusion of probiotics and/or organic acids enhanced humoral- and cell-mediated immunity and decreased the counts of E. coli and Salmonella in the gut, and reduced total bacterial count in breast meat. HIGHLIGHTS Probiotics and/or organic acids enhanced immunity. Probiotics and/or organic acids improved meat safety. Probiotics and/or organic acids could be used as growth promoters.

Influence of residual blood on the physico-chemical characteristics of beef during postmortem refrigerated storage

Inefficient and improper bleeding causes more blood and subsequently more haemoglobin (Hb) to be retained in the muscles, which acts as powerful promoters of lipid oxidation and may decrease the shelf life of meat and meat products. A study was carried out at the Meat Technology Unit, Kerala Veterinary and Animal Sciences University, Mannuthy to examine the effect of bleeding efficiency on certain physico-chemical characters of muscle samples upon post-mortem refrigerated storage at 4±1 ‘C. Muscle samples were collected from imperfectly bled (IB), scientifically slaughtered (SS) and cold slaughtered (CS) carcasses and were packed in HDPE packages and the pH, lipid oxidation and total viable count of the muscle samples were evaluated during a six-day post-mortem refrigerated storage at 4± 1′ C. The mean Hb concentration (mg/g) of IB and CS carcasses (0.07±0.003 and 0.09±0.008, respectively) were significantly (p<0.01) higher than that from SS carcasses (0.05±0.004). The pH values estimated for IB, SS and CS muscle samples on day 0 and day 6 were 6.35±012 and 5.66±0.035, 6.19±0.104 and 5.93±0.174 and 6.46±0.05 and 5.62±0.07, respectively. The thiobarbituric acid reacting substances value (TBARS, mg malonaldehyde/kg) increased significantly from 0.34±0.08 and 0.34±0.06 at day 0 to 1.02±0.18 and 0.75±0.05 for IB and CS muscles samples, respectively. The total viable count (TVC, log cfu/g) significantly increased from 5.29±0.07 and 5.24±0.02 at day 0 to 5.56±0.12 and 5.45±0.06, respectively for IB and CS muscle samples. No significant difference was found in the TVC and TBARS values for SS muscle samples. The results revealed that the level of bleeding had no significant influence on the muscle pH on storage at 4± 1′ C, but had effect on the oxidative stability as well as the microbiological quality. The microbiological quality and oxidative stability of meat samples which underwent complete bleeding were superior to the other samples on all days of storage. Thus, it was concluded that bleeding levels do affect meat quality. Hence, it can be concluded that higher levels of residual blood can result in enhanced lipid oxidation and higher total viable count in meat upon storage at 4± 1′ °C. However, lipid oxidation status and total viable count of cold slaughtered meat were not significantly different for samples from IB carcasses.

Intramammary infections and somatic cell counts in meat and pelt producing ewes with clinically healthy udders

Mastitis in sheep is common and is important both from an economic and from a welfare point of view. It can be either clinical or subclinical, bacterial or, more seldom, lentiviral. There are no data on the national prevalence of subclinical mastitis (SCM) or intramammary infection (IMI), and causative pathogens, in ewes in Sweden.Diagnosis of SCM and/or IMI is based on inflammatory indicators, measured in milk and additional bacteriology. Somatic cell count (SCC) is the most widely used indicator of SCM and/or IMI and can be measured either directly or indirectly with e.g. California Mastitis Test (CMT). However, the use of SCC as an indicator for mastitis and/or IMI in ewes is not fully evaluated, especially not in meat- and pelt producing herds. The aim of this study was therefore to investigate the prevalence of IMI and bacterial panorama in ewes with clinically healthy udders, in meat- and pelt producing herds in Sweden. Moreover, we wanted to define a cut-off for SCC and CMT for detecting ewes with IMI that would be suitable for use under field conditions.Udder half milk samples (n=2134) were collected at weaning and lambing from meat- and pelt producing ewes (n=773), in 22 farms in Sweden. Only clinically healthy animals were included in the study. Milk samples were analysed for bacteriology and SCC and were given a CMT score.Intramammary infection was found in 30% of the ewes and in 14% of the udder half milk samples. No bacteria were found in 74% of the milk samples, and mixed flora was found in 12% of the samples. Among the 287 milk samples where IMI was identified, coagulase negative staphylococci (CoNS) were most prevalent (58%) followed by Staphylococcus (S.) aureus (9%) and Mannheimia (M.) haemolytica (6%). Among the 165 CoNS findings S. simulans was the most common (26%), followed by S. warneri, S. equorum, S. xylosus, S. haemolyticus and S. chromogenes. A CMT score of ≥3 and a SCC of ≥500,000 cells/ml at weaning or CMT score ≥3 and a SCC of ≥400,000 cells/ml after lambing gave the highest possible Se at the same time as the highest possible Sp for identifying udder halves with IMI and may be used for screening for IMI in Swedish meet and pelt producing herds.To conclude, one third of Swedish meat- and pelt producing ewes without clinical signs in the udder had IMI in one or both udder halves at weaning and or after lambing, and CoNS was the most common bacterial finding. A high SCC (≥400,000–500,000 cells/ml) was associated with IMI and a difference in having a high (CMT 3–5) or low (CMT 1–2) between udder halves can be used as an indicator of IMI under field conditions.

The Effect of Using Some Aromatic Medical Herbs in Broiler Diet on Biochemical Characteristics of Blood, Immune Organs and Bacteria Count in Broiler Carcasses

The objective of this study is to determine the effect of diet supplementation with coriander seed and rosemary leaves or a mixture for them on biochemical characteristics of blood, immune organs and bacteria count in meat of broiler carcass (colony forming unit/g). A total of 1080 broiler chicks , Ross-308 at one day old, were randomly allocated for nine treatment groups . Chicks in each treatment group were subdivided for three replicates with 40 chicks for each replicate. Chicks in the first and second treatment are fed on diet supplemented with coriander seed (0.25 % and 0.50 % ) , respectively . While, chicks in the third and fourth treatment are fed diet with rosemary leaves (0.25 % and 0.50 %) , respectively . Also, Mixed of the two medical herbs are added to fifth, sixth, seventh and eighth treatment .Whereas, chicks in the ninth treatment are fed diet without medical herbs supplementation and used as a control group. At marketing age (42d) 12 blood samples are taken to measure the total protein and glucose in serum. Also 9 birds from each treatment group are culled to determine Bursa and spleen weight. Also, the relative weight of Spleen and Bursa Index are calculated. Total bacteria count (colony forming unit(cfu)/ g )and coliform and Salmonella in each one gram of mixed meat from each treatment are recorded. Data show that dietary treatment doesn't significantly affect the serum protein contain, relative weight of bursa and bursa index. However the dietary treatment is significantly ( p < 0.05) increases the serum glucose and spleen relative weight . Total bacteria count, coliform and salmonella count are not affected by dietary treatment. In conclusion, diet supplementation with Rosemary or coriander seed has an effect on biochemical characteristics of blood, immune organs and bacterial count.

A Study on Standard of Buffalo Meat Hygiene in Dharan

Hygiene standard of buffalo meat in Dharan was assessed by microbiological analyses and field survey method. Ten samples of buffalo meat, knives, chopping board and hands of butchers were examined for total plate count (TPC), total coliforms, E. coli, Staphylococcus aureus, Salmonella and Shigella. Average of TPC, Coliforms, E. coli and S. aureus counts in meat were 3.59×107, 2.06×104, 1.69×103 and 9.67×103 cfu/g respectively. Salmonella was detected in 80% samples and all samples were Shigella positive. The average TPC count of chopping board, knives and hands were found to be 3.15×104, 3.47×103 and 2.01×104 cfu/ cm2 respectively. The average Coliform, E. coli and S. aureus counts of chopping board were found to be 1.11×103, 9.8× 101 and 6.2×102 cfu/cm2. The average Coliform, E. coli and S. aureus counts of knives were found to be 1.31×103, 1.66×102 and 2.83×102 cfu/cm2. The average Coliform, E. coli and S. aureus counts of the palms of butchers were found to be 1.95×103, 1.66×102 and 1.77×102 cfu/cm2. Two chopping boards, three knives and three hands were found Salmonella free. Five chopping boards, three knives and two hands were detected for Shigella. The field survey of 31 meat shops showed that the hygiene condition of meat sold in Dharan was found unsatisfactory. DOI: http://dx.doi.org/10.3126/jfstn.v7i0.10617 J. Food Sci. Technol. Nepal, Vol. 7 (99-101), 2012

Response of microbial time temperature indicator to quality indices of chicken breast meat during storage

A prototype of lactic acid bacteria-based time temperature indicator (TTI) was applied to vacuum packed chicken breast meat. Responses of the microbial TTI produced in our laboratory were measured in titratable acidity (TA) during storage. The TTI responses were correlated with the meat qualities over the storage periods at different temperatures. The relationships between the coliform bacteria (CB) counts of meat and the TA of TTI were almost the same for all storage temperatures, because CB counts and TTI had the most similar Arrhenius temperature dependence. The other meat quality indices also showed the similar tendency in the relationships but disagreement between the temperatures increased in the order of lactic acid bacteria counts, volatile basic nitrogen, aerobic mesophilic bacteria counts, and thiobarbituric acid reactive substance. In conclusion, the microbial TTI prototype was found to be a beneficial tool in predicting the quality changes of chicken breast meat during storage.

Effect of Modified Lysozyme on the Microflora and Sensory Attributes of Ground Pork

The effects of lysozyme monomer and thermochemically modified lysozyme on the microflora and sensory attributes of heated and unheated ground pork were investigated in this study. The dimer and trimer fractions of the modified lysozyme were 36.1 and 33.5%, respectively. The modified lysozyme exhibited higher hydrophobicity (40,600 U/mg of protein) and lower enzymatic activity (1,020 U/mg of protein) than the hydrophobicity (890 U/mg of protein) and activity (17,950 U/mg of protein) of the lysozyme monomer. Portions of ground pork (150 g) without lysozyme or supplemented with 5 mg/g lysozyme or modified lysozyme and either not heated or heated at 60°C for 10 min were stored at 4 ± 1°C and sampled at various times between 1 and 144 h. Meat color was not affected by either additive. After storage for 72 h, the mean odor score for meat supplemented with modified lysozyme and heated decreased from 5.0 at 1 h to 4.1, while the scores for all the other preparations were ≤3.2. After 144 h, the counts of Pseudomonas and Enterobacteriaceae in meat that was supplemented with modified lysozyme and not heated were, respectively, 1.1 and 0.9 log less than in the controls, and the numbers in such meat that was heated were, respectively, 1.2 and 2.4 log less than the numbers in the controls. The counts in meat supplemented with lysozyme and the controls were comparable. Heat treatment increased the bacteriostatic effect of modified lysozyme on gram-negative bacteria.

Thermal Inactivation of Sodium-Habituated Staphylococcus aureus in Ready-to-Heat Sauces

The objective of this study was to evaluate the effect of sodium habituation on thermal resistance of Staphylococcus aureus in various ready-to-heat (RTH) sauces. The strain mixture of S. aureus strains KACC10768, KACC10778, KACC11596, KACC13236 and NCCP10862 was habituated up to 9% of NaCl. The inocula of NaCl-habituated and non-habituated S. aureus were inoculated in 5 g portions of pork cutlet, meat and Carbonara sauces at 7 Log CFU/g, and the samples were vortexed vigorously. The inoculated samples were then exposed to 60 and <TEX>$70^{\circ}C$</TEX> in a water-bath, and survivals of total bacteria and S. aureus were enumerated on tryptic soy agar and mannitol salt agar, respectively, every 30 min for 120 min. At 60oC, the cell counts of total bacteria and the significant difference in survivals between sodium-habituated and non-habituated S. aureus were observed only in the Carbonara sauce; the tailing effect, which is the period of no reduction of bacterial cell counts, was observed in pork cutlet, meat and Carbonara sauces subjected to <TEX>$60^{\circ}C$</TEX>. At <TEX>$70^{\circ}C$</TEX>, total bacterial populations and sodium-habituated and non-habituated S. aureus cell counts in meat and Carbonara sauce also significantly decreased (p<0.05) after 30 min of heat treatment, followed by the obvious tailing effect. Sodium-habituated S. aureus cell counts in meat and Carbonara sauces were higher (p<0.05) than those of non-habituated S. aureus at <TEX>$70^{\circ}C$</TEX>. The results indicate that sodium habituation of S. aureus cells may increase the thermal resistance of the pathogen in RTH sauces; moreover, heating RTH sauces for a short time before serving may not sufficiently decrease the cell counts of S. aureus, particularly for sodium-habituated strain.

Meat quality of heat stress exposed broilers and effect of protein and vitamin E

1. This study was designed to determine the effects of heat stress exposure on broiler fattening performance, meat quality and microbial counts. 2. Six groups were established: CHP (24°C + 210 g/kg crude protein (CP)), SHP (34°C + 210 g/kg CP), CLP (24°C + 190 g/kg CP), SLP (34°C + 190 g/kg CP), SHPVE (34°C + 210 g/kg CP + Vitamin E) and SLPVE (34°C + 190 g/kg CP + Vitamin E) groups. 3. It was determined that the body weights of the male animals included in Group CHP displayed statistically significant differences in comparison to those of Groups SHP, CLP and SLP. Furthermore, it was ascertained that the values of Group CLP also displayed statistically significant differences in comparison to those of Groups CHP, SHP and SLP. The feed consumptions in Groups CHP and CLP were significantly different from those of the remaining groups, excluding Group SHP. The highest feed conversion rate was determined in Group SHPVE. 4. When evaluated for chicken drumstick TBA values, Group CHP differed significantly from Groups SHP, SHPVE, CLP and SLP, whilst Group CLP differed significantly from Groups SHP, SHPVE and SLP. On the other hand, when evaluated for breast meat TBA values, Group CHP displayed statistically significant differences in comparison to Groups SHP, SLP and SLPVE, whilst Group CLP differed significantly from Groups CHP, SHP, SLP and SLPVE. 5. The sensitivity of breast meat to colour susceptibility was greater than that of chicken drumsticks. While storage period affected the TBA values and microbial counts of meat significantly, its effect on colour parameters was found to be variable. Trial groups significantly affected total aerobic mesophilic bacteria counts in chicken drumsticks, and Enterobacteriaceae and total aerobic mesophilic bacteria counts in breast meat. 6. In conclusion, heat stress adversely affected final body weights and the lipid oxidation of meat, whilst vitamin E alleviated these adverse effects.

Combination of Origanum vulgare L. essential oil and lactic acid to inhibit Staphylococcus aureus in meat broth and meat model.

This study assessed the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare L. essential oil and lactic acid against Staphylococcus aureus by the determination of Fractional Inhibitory Concentration (FIC) index and cell viability in meat broth and meat model. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the oil was 0.6 and 1.25 µL.mL-1, respectively. Lactic acid showed MIC and MBC of 2.5 and 5µL.mL-1, respectively. FIC indices of the combined application of the oil and lactic acid were 0.5 showing a synergic interaction. The essential oil and lactic acid showed similar (p>0.05) anti-S. aureus effect in meat broth over 96 h of exposure. Treatment with essential oil or lactic acid presented a smaller anti-staphylococcal effect in meat in comparison to meat broth. No significant difference (p>0.05) was found for the microbial counts in meat treated with each antimicrobial alone or in mixture. These results could arise as an interesting approach for the improvement of food preservation using more natural procedures, considering the current demand of consumer and sensory quality of foods.

Comparison of Bacterial Counts in Meat at 7°, 30°and 35°C

Comparative Studies on Viable Bacterial Count in Meat at Different Temperatures of Incubation.The viable bacterial count was determined in sliced commercial raw pork after incubation at 7, 30, and 35°C. It was compared among these temperatures. Then, formula were prepared mutually to estimate the viable bacterial count at each of the there incubation temperatures by using a regression formula.The following result were obtained.1) When converted into common logarithm, the viable bacterial count in the commercial raw pork showed almost the same distribution as the normal distribution, regardless of the incubation temperature, 7, 30, or 35°C.2) The viable bacterial count was compared between the culture at 7°C and that at 35°C and between the culture at 30°C and that at 35°C. It was higher in the culture at 35°C than that at any other temperature when it was relatively low. It was higher in the cultures at 7 and 30°C than in that at the other temperature when it was relatively high. There were significant differences in the viable bacterial count among the cultures at 7, 30, and 35°C.3) The viable bacterial count was higher in the cultures at 7 and 30°C than in that at 35°C when it was in the order of approximately 104.4) Relationships of correlation and regression were noticed among the viable bacterial counts of the cultures at the three incubation temperatures. It was demonstrated that the regression formula obtained was useful (regression coefficient, b≠0) .In conclusion, it was possible to estimate the viable bacterial count mutually in cultures at different temperatures of incubation by using the formula obtained for estimation.

Some Observations on the Bacteria in Frozen Pork Sausage

The general use of the locker plants for the storage of perishable products such as meat, poultry, fruits, and vegetables by individual families, represents one of the most recent developments in the field of food distribution and preservation. The preservation of food by freezing depends upon retarding the rate of microbial, enzymatic, and chemical changes. It is generally agreed that meat and meat products should be sharp frozen at -10? F. (-23.3? C), and stored at 0? F. (-17.8? C) or lower to retard such changes. Work conducted by the Kansas Agricultural Experiment Station indicates that the quality of fresh pork is preserved for a longer period when frozen and stored at the lower temperature.' The presence of micro-organisms in frozen meat may not be important from a pathogenic viewpoint, but their presence may be influential in determining the storage life of meat or meat products. The presence of large number of bacteria in meat may be attributed to the method of handling the meat prior to freezing, such as careless management or improper ageing. It is a recognized fact that psychrophilic organisms will continue to multiply at chill room temperatures. These high bacterial counts in meat have raised a question in regard to the keeping quality and storage life of the product. Since the locker industry has grown so rapidly, a need for further study on the effect of the bacterial flora upon the quality of such meats when frozen is necessary. In this study fresh pork sausage was used to determine the influence of bacteria upon the keeping quality. The sausage was made from fresh pork trimmings comprised of approximately 75 per cent lean and 25 per cent fat, and seasoned with 1 pound salt, 2 ounces pepper, and 2 ounces sage for each 50 pounds of meat. This formula is recommended by the Kansas Agricultural Experiment Station.2 Four trays of trimmings were prepared and designated as M, N, 0, and P. Each tray of trimmings was made from pork carcasses which were aged in the cooler for varied lengths of time as indicated in Figure 1. This aging period allowed time for the bacterial flora common to each carcass to multiply. The four blocks of sausage were prepared and placed in a 34? F. cooler for 24 hours prior to packaging. A series of one-pound packages