Ground Chicken Research Articles

Impacts of pre-rigor salting with KCl on technological properties of ground chicken breast

The objective of this study was to determine the impact of pre-rigor salting using KCl on the technological properties of ground chicken breast. Chicken breast muscle (M. pectoralis major and minor) was hot-debonded and salted with 2% NaCl (w/w), 1% NaCl+1% KCl mixture, or 2% KCl, respectively, within 30 min after slaughter. Post-rigor salting treatment was prepared with 2% NaCl at 24 h postmortem. All pre-rigor salting treatments showed higher ultimate pH, protein solubility, and final yield than post-rigor salting treatment (P < 0.05). However, the positive effects of pre-rigor salting on chicken breast differed by salt type. Pre-rigor salting with KCl resulted in higher ultimate pH and R-values of chicken breast than pre-rigor salting with NaCl (P < 0.05). Despite the high ultimate pH, pre-rigor salting with KCl resulted in lower protein solubility, final yield, and hardness of chicken breast than pre-rigor salting with NaCl (P < 0.05). These results indicate that pre-rigor salting with KCl could contribute to the maintenance of relatively excellent technological properties of pre-rigor chicken breasts compared to post-rigor salted chicken breast. However, this current study also suggests that the impact of KCl on technological properties in pre-rigor chicken breast, such as water-holding capacity, protein solubility, and texture, could be less effective than pre-rigor salting with NaCl at an identical percentage concentration.

Inactivation of extraintestinal pathogenic E. coli suspended in ground chicken meat by high pressure processing and identification of virulence factors which may affect resistance to high pressure

Extraintestinal pathogenic Escherichia coli (ExPEC) are responsible for urinary tract infections, inflammatory bowel disease, sepsis and meningitis. Retail poultry meat has been identified as the main reservoir for ExPEC in food. Information regarding ExPEC virulence factor (VF) or antibiotic resistance (AR) involvement with resistance to high-pressure inactivation in food is lacking. In this study we inoculated ground chicken meat with 22 individual isolates of clinical uropathogenic E. coli (UPEC) and newborn meningitis causing E. coli (NMEC), and isolates from retail chicken meat. We then determined their high-pressure inactivation kinetics (D10-value). The mean D10-value for all isolates (n = 22) was 3.26 min at 400 MPa. The mean D10-value for the UPEC, NMEC, chicken isolates were 5.0, 1.3, 2.23 and 4.98 min at 400 MPa, respectively. The D10 varied widely between the 22 isolates. The mean D10-value for the clinical isolates was 3.33 vs. 3.15 for the non-clinical isolates. The NMEC strains were more sensitive to HPP. ExPEC lacking chuA, cnf1, sinH, papG, hlyA, vat, yncD were more resistant to HPP, indicating ExPEC VF could play a role in high pressure resistance. HPP at 600 MPa for 3 min resulted in >6 log10 reductions for UPEC, NMEC, and retail chicken product isolates.

Effects of Pyruvic Acid, Succinic Acid, and Oregano Essential Oil on Salmonella, Natural Microflora, and Quality of Raw Ground Chicken

ObjectivesThe growing stringency of regulations related to pathogens in raw poultry and increasing consumer demand for more natural food ingredients makes it imperative to explore alternative antimicrobial agents. The aim of this study was to assess the anti-Salmonella effect of combinations of succinate or pyruvic acid with oregano essential oil in raw ground chicken. Additionally, their effect on natural microflora and quality of ground chicken over simulated retail display was evaluated.Materials and MethodsNalidixic acid (NA) adapted Salmonella Typhimurium was inoculated on skin-on broiler breast meat pieces. The antimicrobial treatments given to meat were 2 and 3% pyruvic acid (PA) or monosodium succinate (SA) in combination with 0.5% essential oil (EO). Agar at the concentration of 0.05% was added to water used to prepare antimicrobial solutions to disperse the essential oil. Mode of antimicrobial treatment was 30 s dip. The meat was then ground and evaluated for pathogen reduction. Data were analyzed using 1-way ANOVA. Surviving Salmonella were recovered on XLT-4 with 50 ppm NA. Non-inoculated meat was similarly treated with antimicrobial dip and ground. Ground chicken was packaged in foam trays with PVC overwrap, and evaluated for mesophilic aerobic plate count (APC), psychrotrophic count (PC), pH, instrumental color (CIE L*, a*, and b*), and expressible moisture over 8 d of simulated retail display.A factorial design was assigned to the experiment with antimicrobial treatments and display days as the fixed effect factors. Data were analyzed using a mixed general linear model that considered replicates as a random effect in addition to the mentioned fixed effects. All trials were conducted in three replicates.ResultsMaximum reduction obtained in Salmonella counts from ground chicken was 1.52 log CFU/g and 0.98 log CFU/g, resulting from 3% SA + 0.5% EO, and 3% PA + 0.5% EO, respectively. Three percent SA + 0.5% EO treatment resulted in ground chicken with approximately 1.2 log CFU/g lower APC on Day 8 that was significantly lower (P &lt; 0.05) than all other treatments. This treatment also resulted in less pH variation over the entire shelf life duration and lighter color of ground meat on Day 8.ConclusionThese results indicate that combination of monosodium succinate and oregano essential oil provides effective reduction of Salmonella and improved raw quality of ground chicken. This antimicrobial combination can be employed as a clean label ingredient for raw chicken applications.

Effects of partial and complete replacement of added phosphates with encapsulated phosphates on lipid oxidation inhibition in cooked ground meat during storage.

The objective of this research was to investigate the influence of various levels (0.0, 0.1, 0.2, 0.3, 0.4, 0.5%) of added encapsulated polyphosphates (sodium tripolyphosphate; sodium pyrophosphate) combined with unencapsulated polyphosphate to total 0.5% on the inhibition of lipid oxidation in cooked ground meat (beef, chicken) during refrigerated storage (0, 1, 7 d). The use of sodium tripolyphosphate (encapsulated sodium tripolyphosphate, unencapsulated sodium tripolyphosphate) led to lower cooking loss compared to sodium pyrophosphate in both meat species (p < 0.05). Increasing encapsulated sodium tripolyphosphate up to 0.3% decreased cooking loss in ground beef (p < 0.05). Added encapsulated polyphosphate at 0.5% had the same effect on pH as 0.5% unencapsulated polyphosphate in the cooked ground beef and chicken. A higher accumulation of orthophosphate was determined in the samples with sodium tripolyphosphate compared to those with sodium pyrophosphate (p < 0.05). Inclusion of a minimum of 0.1% encapsulated polyphosphate decreased thiobarbituric acid reactive substances and lipid hydroperoxides on 7 d. Increasing encapsulated sodium tripolyphosphate and encapsulated sodium pyrophosphate up to 0.2% in beef decreased thiobarbituric acid reactive substances at 7 d. Addition of 0.4% encapsulated sodium tripolyphosphate and 0.3% encapsulated sodium pyrophosphate in chicken prevented any increase in TBARS during storage. Incorporating encapsulated sodium pyrophosphate at 0.3% inhibited lipid hydroperoxide formation in beef and chicken. The meat industry could achieve enhanced lipid oxidation inhibition by replacing some of the unencapsulated polyphosphate with encapsulated polyphosphate in their product formulations.

Antimicrobial effects of pyruvic and succinic acids on Salmonella survival in ground chicken

This study was designed to assess the antimicrobial effect of pyruvic or succinic acid with oregano essential oil on Salmonella survival, composition of natural microflora, and resultant ground meat quality. Various concentrations of pyruvic (PA) and succinic acids (SA) with 0.5% essential oil (EO) were applied as immersion treatments for broiler breast meat. Salmonella Typhimurium was inoculated on breast meat to evaluate its post-treatment reduction in ground meat. For assessing impact of antimicrobial treatments on ground product, non-inoculated meat was treated with antimicrobials, ground, and stored for retail display in foam trays. Treated ground product was further evaluated for natural microbial counts, instrumental color, pH, and expressible moisture over 8 days of retail display. A combination of 3 g/100 ml SS + 0.5 ml/100 ml EO showed a maximum reduction of 1.52 log CFU/g for Salmonella on ground chicken. The same treatment (3 g/100 ml SS + 0.5 ml/100 ml EO) resulted in reduction of bacterial population ca. 1.2 log CFU/g aerobic plate count and lower pH and L* variation over the 8 d of storage. (P < 0.05) than all other treatments. Results obtained from this study indicate that broiler meat treatment with PA or SA with EO will provide effective reduction of Salmonella and improved raw ground meat quality.

Effect of Tapioca Flour on Physicochemical Properties and Sensory Descriptive Profiles of Chicken Breast Meat Patties

SUMMARY The objective of this study was to investigate the effects of tapioca flour (TF) on physicochemical properties and sensory qualities of chicken breast meat patties. The effects were also compared with some other commonly used meat binders. Ground chicken breast meat was either mixed with different concentrations of TF (1%, 2%, or 4% w/w) or mixed with 2% TF, potato flour, garbanzo flour, or egg white. Raw meat pH, color and cook loss and cooked meat expressible moisture, shear force, and sensory flavor and texture profiles were evaluated. The addition of TF reduced pH, cook loss, expressible moisture, and shear force and increased L* values (P 0.05) in pH, L*, and b* values; however, they had lower cook loss, expressible moisture, and shear force (P

Process risk model for Salmonella and ground chicken.

To develop a process risk model (PRM) for evaluating the safety of individual lots of ground chicken (GC) contaminated with Salmonella (Salm). Data for prevalence, number and serotype of Salm were collected with 25g samples of GC using a combination of methods (whole sample enrichment, quantitative polymerase chain reaction, cultural isolation and serotyping). These data were used to develop a predictive model for Salm contamination of GC as a function of serving size from 25 to 300g. This model was combined with a model for thermal inactivation of Salm in GC and a dose-response model for Salm to develop a PRM in Excel that was simulated with NeuralTools and @Risk. Of 100, 25g samples of GC examined, 19 tested positive for Salm. Three serotypes were isolated: Infantis (n=13), Enteritidis (n=5) and Typhimurium (n=1). The number of Salm ranged from 0 to 2·56 log with a median of 0·93 log per 25g of GC. The PRM predicted that Salm prevalence would increase (P<0·05) from 19 to 57% to 82 to 93% as serving size increased from 25 to 100g to 200 to 300g. However, the total number of Salm in a 100-kg lot of GC and total severity of illness (TSI) were not affected (P>0·05) by serving size. The PRM was also used to evaluate effects of serving size distribution, cooking, food consumption behaviour, consumer demographics and Salmonella virulence on TSI. How a lot of GC is partitioned and consumed does not affect TSI. Scenario analysis demonstrated that the PRM can integrate prevalence, number and serotype data for Salm with consumer handling, consumption and demographics data to identify safe and unsafe lots of GC for improved food safety and public health. Process-risk models like the one developed in this study represent a new, holistic approach to food safety that holds great promise for improving public health and reducing food recalls.

Growth of Clostridium perfringens in cooked chicken during cooling: One-step dynamic inverse analysis, sensitivity analysis, and Markov Chain Monte Carlo simulation

The objective of this study was to determine the kinetic parameters and apply Markov Chain Monte Carlo (MCMC) simulation to predict the growth of Clostridium perfringens from spores in cooked ground chicken meat during dynamic cooling. Inoculated samples were exposed to various cooling conditions to observe dynamic growth. A combination of 4 cooling profiles was used in one-step inverse analysis with the Baranyi model as the primary model and the cardinal parameters model as the secondary model. Six kinetic parameters of the Baranyi model and the cardinal parameters model, including Q0, Ymax, μopt, Tmin, Topt, and Tmax, were estimated.The estimated Tmin, Topt, and Tmax were 14.8, 42.9, and 50.5 °C, respectively, with a μopt of 5.25 h−1 and maximum cell density of 8.4 log CFU/g. Correlation analysis showed that both Q0 and Ymax are weakly correlated to other parameters, while the remaining parameters are mostly mildly to strongly correlated with each other. Although it may be difficult to estimate highly correlated parameters using a single temperature profile, one-step analysis with multiple different temperature profiles helped estimate them successfully.The estimated parameters were used as the prior information to construct the posterior distribution for Bayesian analysis. MCMC simulation was used to predict the bacterial growth using different dynamic temperature profiles for validation of the accuracy of the predictive models. The MCMC simulation results showed that the Bayesian analysis produced more accurate predictions of bacterial growth during cooling than the deterministic method. With Bayesian analysis, the root-mean-square-error (RMSE) of prediction was only 0.1 log CFU/g with all residual errors within ±0.25 log CFU/g. Therefore, Bayesian analysis is recommended for predicting the growth of C. perfringens in cooked meat during cooling.

Development of mycoinsecticide formulations with Beauveria bassiana and Metarhizium anisopliae for the control of lesser mealworm, Alphitobius diaperinus, in chicken broiler houses

Entomopathogenic fungi are promising alternatives to synthetic chemicals for controlling lesser mealworm populations in broiler houses. Granular formulations of two isolates of the fungi Beauveria bassiana and Metarhizium anisopliae based on ground chicken feed pellets produced 98 and 87% larval mortality, respectively, after 11 days’ exposure to ≈ 0.2 g conidia/54 g formulation m−2 in the laboratory. Oil based formulations with canola oil and Codacide™ were generally slower to produce mortality but still significantly effective. Granular formulations were effective on a range of broiler-house substrates (new and used litter, soil) of varying pH and moisture content. The efficacy of the M. anisopliae isolate appeared enhanced and the B. bassiana isolate inhibited on damp new litter (40% moisture). Substrate pH (3.45–6.38) did not discernibly inhibit fungal efficacy. Granular formulations of both fungal isolates tested at average broiler-house temperatures were ineffective at 35 °C but became active when re-tested at 30 °C. Granular mycoinsecticide formulations based on the two isolates are now ready for testing in commercial broiler houses.

Inactivation of extraintestinal pathogenic E. coli clinical and food isolates suspended in ground chicken meat by gamma radiation

Extraintestinal pathogenic Escherichia coli are common contaminants in retail poultry and involved inflammatory bowel disease, urinary tract infections and meningitis in both animals and humans. They cause significantly more illnesses and deaths in humans than Shiga toxin-producing E. coli (STEC). Ionizing radiation is used commercially for improving the safety and shelf-life of foods. In this study we inoculated ground chicken meat with 25 individual isolates of clinical uropathogenic E. coli (UPEC) and newborn meningitis causing E. coli (NMEC), isolates from retail chicken meat (CM), as well as retail chicken-skin isolates identified in our laboratory (CS). We then determined their gamma radiation inactivation kinetics (D10-value). The mean D10-value for all isolates (n = 25) was 0.30 kGy. The mean D10-value for the UPEC, NMEC, CM, and CS isolates were 0.25, 0.29, 0.29, and 0.39 kGy, respectively. The mean D10-value for the clinical isolates was 0.27 kGy vs. 0.34 kGy for the non-clinical isolates. There was no correlation between presence of virulence factors, antibiotic resistance, and radiation resistance. ExPEC were similar to that of STEC which were previously evaluated in our laboratory. The radiation doses needed to kill STEC poultry meat should also kill ExPEC.

Fatty acid composition and quality properties of chicken sausage formulated with pre-emulsified perilla-canola oil as an animal fat replacer

The potential use of an oil in water (o/w) emulsion made from perilla and canola oil in chicken sausage as an animal fat replacer was assessed. The (o/w) emulsion was made from 50% (wt/wt) perilla-canola oil mixture in a 30:70 ratio, 3.20% (wt/wt) polyglycerol polyricinoleate, 4.48% (wt/wt) soy protein isolate, 14% (wt/wt) inulin, and 28.32% (wt/wt) water. The sausages were manufactured with 60% (wt/wt) ground chicken breast, 20% (wt/wt) fat (beef tallow as a control), and 20% (wt/wt) ice water. Full replacement of animal fat with a perilla-canola oil (o/w) emulsion reduced the fat content and estimated calories but increased the moisture, protein, ash, and carbohydrate content. The proportion of α-linolenic acid (C18:3n3) was increased when animal fat was replaced with either a perilla-canola oil mixture or pre-emulsified perilla-canola oil, resulting in a lower n6 to n3 polyunsaturated fatty acid ratio than the control. The perilla-canola oil (o/w) emulsion improved emulsion stability and minimized cooking loss during sausage manufacturing. Higher L* value (lightness) and whiteness were observed in the sausages formulated with the perilla-canola oil mixture, followed by the pre-emulsified perilla-canola oil and the control. The perilla-canola oil (o/w) emulsion also increased the hardness but maintained an acceptable appearance, flavor, and overall impression similar to the control. The shelf life could be extended by vacuum packing and storing the cooked sausages formulated with a perilla-canola oil (o/w) emulsion for 30 D at 2 ± 1°C. Pre-emulsified perilla-canola oil could be used to replace animal fat in reduced-fat chicken sausage manufacture.

The Effect of Previous Life Cycle Phase on the Growth Kinetics, Morphology, and Antibiotic Resistance of Salmonella Typhimurium DT104 in Brain Heart Infusion and Ground Chicken Extract.

Growth models are predominately used in the food industry to estimate the potential growth of selected microorganisms under environmental conditions. The growth kinetics, cellular morphology, and antibiotic resistance were studied throughout the life cycle of Salmonella Typhimurium. The effect of the previous life cycle phase [late log phase (LLP), early stationary phase (ESP), late stationary phase (LSP), and early death phase (EDP)] of Salmonella after reinoculation in brain heart infusion broth (BHI), ground chicken extract (GCE), and BHI at pH 5, 7, and 9 and salt concentrations 2, 3, and 4% was investigated. The growth media and previous life cycle phase had significant effects on the lag time (λ), specific growth rate (μmax), and maximum population density (Ymax). At 2 and 4% salt concentration, the LLP had the significantly (p < 0.05) fastest μmax (1.07 and 0.69 log CFU/ml/h, respectively). As the cells transitioned from the late log phase (LLP) to the early death phase (EDP), the λ significantly (p < 0.05) increased. At pH 5 and 9, the EDP had a significantly (p < 0.05) lower Ymax than the LLP, ESP, and LSP. As the cells transitioned from a rod shape to a coccoid shape in the EDP, the cells were more susceptible to antibiotics. The cells regained their resistance as they transitioned back to a rod shape from the EDP to the log and stationary phase. Our results revealed that growth kinetics, cell’s length, shape, and antibiotic resistance were significantly affected by the previous life cycle phase. The results of this study also demonstrate that the previous life cycle should be considered when developing growth models of foodborne pathogens to better ensure the safety of poultry and poultry products.

Assessing the effectiveness of revised performance standards for Salmonella contamination of comminuted poultry

Revised Salmonella performance standards for ground chicken and turkey were chosen based on a risk assessment model that predicted a 25% reduction in occurrence of human exposures to Salmonella-contaminated comminuted products following implementation of the standards.To assess the validity of the risk assessment model and its predictions, this study uses a Bayesian framework to compare prior and posterior distributions for model parameters. Prior distributions are informed by 24 months of data collected before the performance standards were implemented. The posterior distributions are generated using a sampling-importance resampling algorithm based on 36 months of data collected after implementing the standards.For the comminuted turkey model parameters, prior and posterior distribution comparisons suggest that the 25% reduction target was accomplished. In contrast, the results for comminuted chicken suggest that the actual reduction in Salmonella was somewhat less than the 25% target. For both commodities, the analysis does not invalidate the risk assessment model, although it does suggest areas for modification in the future.

Effect of rosemary extract on microbial growth, pH, color, and lipid oxidation in cold plasma-processed ground chicken patties

Effects of adding 1% rosemary extract were determined on the microbial growth and quality characteristics of ground chicken breast patties treated with in-package dielectric-barrier-discharge (DBD) cold plasma (CP). Chicken patties were CP-treated at 70 kV for 180 s. Total plate counts (TPC), pH, color, and lipid oxidation (LPO) were measured at time 0 and day 5 of storage. ANOVA showed that there were no three-way (rosemary*CP*storage) interactions and no rosemary*CP interaction (P > 0.05) regardless of measured variable, indicating that rosemary extract has the same effects on CP treated patties as on non-CP treated samples regardless of storage. Adding rosemary extract resulted in reduced microbial growth, LPO, and L* values and increased pH, a*, and b* values in both CP treated and non-CP treated patties. In conclusion, rosemary is a promising additive for maintaining microbial quality and controlling LPO in CP-processed meat.

Thermal inactivation of extraintestinal pathogenic Escherichia coli suspended in ground chicken meat

Extraintestinal pathogenic Escherichia coli (ExPEC) is a foodborne pathogen responsible for urinary tract infections, sepsis, and neonatal meningitis. Retail poultry meat has been identified as a reservoir for ExPEC. Information regarding virulence factors (VF) or antibiotic resistance (AR) involvement in resistance to food processing technologies is lacking. In this study, ground chicken meat (GCM) was inoculated three different ExPEC multiisolate cocktails, including Uropathogenic E.coli (UPEC), Neonatal Meningitis causing E.coli (NMEC), and Food-Source (FS) isolates. D10 (55, 60, and 65 °C) (e.g. 7.34, 0.56, 0.05 min, respectively) and z-values (4.62–5.89 °C) were found consistent with, or slightly lower than, those of E. coli O157:H7 in low fat meat and poultry. There was little difference in D10 and z-value when ExPEC were recovered on APC Petrifilms versus E. coli Petrifilms. The D10 of 19 individual ExPEC isolates determined at 55 °C ranged from 1.84 to 7.58 min, with an average of 4.46 min. Differences in D10 were found between isolates possessing or lacking the fdeC, sinH, cnf1, gad, ompT, iha, FimH and Sat genes. These results indicate the ExPEC can be inactivated in poultry meat using the same conditions that are used for E. coli O157:H7. While the possibility exists that ExPEC genotype (VF) can influence survival to thermal processing, AR had no effect on resistance to heat in this study.

The Antimicrobial Properties of A Vinegar-based Ingredient on Salmonella Typhimurium and Psychrotrophs Inoculated in Ground Chicken Breast Meat and Stored at 3±1°C for 7 days

SUMMARY One of the most effective approaches for reducing consumer risk of foodborne illness in poultry is to utilize effective antimicrobials. The objectives of this study were to determine antimicrobial properties of a United States Department of Agriculture Food Safety and Inspection Services-approved vinegar-based ingredient (VBI) on Salmonella Typhimurium inoculated (105 CFU/g) ground chicken breast meat, and to ascertain effects of VBI on total psychrotrophic bacteria and meat pH during storage. Ground chicken was treated with 0% VBI (negative control), 0% VBI-plus inoculum (positive control), and inoculum plus 1, 2, and 3% VBI. Samples were packaged, stored at 3±1°C, and analyzed on days 0, 1, 3, 5, and 7 for total psychrotrophs, Salmonella, and pH. Meat treated with 1, 2, and 3% VBI had lower (P

The effectiveness of bokashi against growth of mustard Brassica juncea L., Brassica rapa L. Pokcay And Maize Zea mays L

This research aims to find out the effectiveness of Bokashi on growing plant. The Research used quantitative methods approach to true experimental Random Design, with complete (RAL) factorial 4 X 3 pattern, that is a factor of growing media and plant type. The plant-ing medium consists of 100% bokashi, 50% bokashi, and two media controls i.e. control by the media and the media ground chicken feces. Kind of plant used are mustard (Bassica juncea L.), pokcay (Brassica rapa L.) and maize (Zea mays L.). In this study there was 12 experimental which each experiment planted at 30 polybags, so there was 360 polybags. The area of the research is in the village of Kebon Agung, Jember Regency. Plants are observated over the three over the three weeks after planting. In the first week, the second week and the third week after planting. The observations focused on the ability of seeds to grow once planted that is growing or not growing. The data were analyzed with ANOVA and Duncan uses of SPSS v20. The results showed that the most effective media was 50% bokashi on Zea mays L.

Preservative effects of rosemary extract (Rosmarinus officinalis L.) on quality and storage stability of chicken meat patties

Abstract The effect of different level of rosemary extract (RE) (Rosmarinus officinalis Linn.) cultivated in Jordan, and other preservative on quality and stability of ground chicken meat was investigated. Treatments, were involved 1) Control (No additive), 2) 300 ppm (RE), 3) 350 ppm RE, 4) 300 ppm L-Ascorbic acid (E-300), 5) 200 ppm Sodium nitrite (E-250), 6) 5 ppm butylatedhydroxyanisole (BHA) for breast, and 14 ppm for thigh meat were prepared. TBARS, total carbonyl, and color values, were measured and analyzed at 0, 4, and 7 day. Samples of cooked thigh meat were prepared, and sensory evaluation was reported. Cooking loss %, ultimate pH, and total aldehydes were analyzed. Both RE and E-250 were showed the highest significant effect maintaining low values of TBARS and total carbonyl at 7 day. However, no significant differences were found among all treatments measuring ultimate pH values, and their cooking loss %. The RE and E-250 also showed the highest significant effect delaying aldehydes formation, and positively affect meat sensory attributes. In conclusion, RE (350 ppm) was very effective antioxidant and comparable to the other commercial antioxidants. Thus, RE could be a good substitution to many synthetic antioxidants used in meat industry.

Salmonella Harborage Sites in Infected Poultry That May Contribute to Contamination of Ground Meat

The role of invasive Salmonella in contamination of ground poultry is poorly defined. Salmonella harborage sites were determined in experimentally infected chickens and turkeys. Bioluminescent-tagged Salmonella were used to follow their spread in bone, meat, and skin following infection. Immunohistochemistry and culture were used to localize Salmonella. Chicken neck skin was positive for S. Heidelberg and S. Typhimurium throughout the experimental period, and the bacteria were localized on the stratum corneum of the epidermis and feather follicles. S. Heidelberg and S. Typhimurium were intermittently detected in drumstick muscle of chickens, with Salmonella primarily localized in connective tissues and lymphatics. Twenty percent of the drumstick muscles were culture positive for Salmonella in chickens at 42 days of age. Blood and tibiotarsus bone were culture positive for S. Heidelberg and S. Typhimurium during the first two weeks of infection. Salmonella levels in neck skin and muscle were <102 CFU/g in chickens at 42 days of age. Multiple S. Heidelberg isolates associated with foodborne outbreaks were used to infect chickens and turkeys to determine whether some strains attained high abundance in the muscle of infected birds. No chicken drumsticks or thighs were Salmonella positive by bioluminescence in chickens at 42 days of age (n = 210). In turkeys, all drumstick muscles (n = 132) and tibiotarsus bone (n = 93) were negative for S. Heidelberg. Thirty percent of the breast skins (n = 93) were culture positive for S. Heidelberg when turkey hens were 11 weeks old. S. Heidelberg were primarily localized on the stratum corneum of the epidermis in turkeys. Exclusion of skin from ground poultry products may be the best option for reducing Salmonella contamination in ground chicken and ground turkey.

Keratin Degradation by Aspergillus niger and Penicillium purpurogenum Isolated from Nigerian Soil

Keratin degrading Aspergillus niger and Penicillium purpurogenum were isolated from soils collected from human hair dumping ground using skim milk agar screening method. These fungi hydrolyzed skim milk casein indicated by halo zones of hydrolysis of 62mm and 64mm produced by them respectively. The fungal species also utilized keratin of ground human hair and chicken feather and hydrolyzed them to reducing sugars and proteins with P. purpurogenum being a better degrader of chicken feather and human hair producing 13.5 and 12.0 U/ml respectively than A. niger.