Meat Surface Research Articles

Dry-aged beef quality with the addition of Mucor flavus – Sensory, chemosensory and fatty acid analysis

Dry-aged beef is a premium product known for its unique taste and aroma. These characteristics are thought to partially depend on the composition of the microorganisms present on the meat surface during ageing. Recently several attempts to standardise this process were made. This study aimed to assess the effect of a fungal biostarter application on the profile of volatile compounds, fatty acid composition and sensory quality of dry-aged beef. The Longissimus muscle used in the experiment originated from 20 crossbred (10 heifers and 10 steers) animals from the crossing of Holstein-Friesian cows with beef breed bulls. A fungal biostarter composed of Mucor flavus strain KKP2092p was used for meat inoculation. Half of the material was aged without the use of a biostarter (Control samples). The dry-ageing of the meat was performed at a temperature of 1.5 °C with approximately 80–90 % relative humidity for 28 days. The use of Mucor flavus KKP2092p improved meat quality attributes (aroma liking, flavour and overall liking) as a result of the formation of specific volatile compounds. The profile of volatile compounds in the meat aged with Mucor flavus and control variants was differentiated. This study also indicated that Mucor flavus biostarter had an impact on the specific fatty acid composition. An insignificant effect of Mucor flavus on lipid oxidation expressed as mg/kg of malonaldehyde was also observed.

Sustainable gelatin-kappa carrageenan active packaging with Mekwiya date seeds to enhance goat meat quality and shelf life

This research aimed to elaborate a gelatin-Kappa carrageenan-based packaging with 0.22 %, 0.44 %, and 0.88 % w/v of Mekwiya date palm seeds extract (DSEMK). This extract improved the mechanical, physical, and thermal properties of the films. Moisture content, water solubility, and water vapor permeability were reduced from 17.54 ± 0.02 to 12.18 ± 0.02, from 77.61 ± 0.02 to 25.35 ± 0.29 %, and from 5.28 ± 0.29 to 1.69 ± 0.03 g s−1 m−1 Pa−1 × 10−10, respectively. During thermal degradation, DSEMK4 film had a residual weight of 27.99 %, compared to 20.67 % for the control. Despite a decline in the film's tensile strength from 24.19 to 8.94 MPa with the incorporation of DSEMK, elongation at the breaking point increased from 37.66 ± 0.16 to 46.17 ± 0.25 %. The film containing DSEMK4 displayed the highest phenolic contents and illustrated the best antioxidant effects in DPPH and FRAP assays, with IC50s of 756 and 1445 μg/mL, respectively and inhibited pathogen growth on the meat surface. Over storage at 4 °C, monitoring of pH, lipid and protein oxidation parameters, microbial spoilage, optical properties, and sensory attributes disclosed that the DSEMK-films successfully enhanced the meat quality and safety. These findings were supported by principal component analysis and heat maps.

Effects of in-package cold plasma treatment on poultry breast meat packaged in high CO2 atmosphere

High CO2 in packages significantly extends microbiological shelf life of poultry meat. Cold plasma is an emerging antimicrobial treatment, which generates various reactive gas species and inactivates microbials effectively. The objective of this study was to explore the potential effects of combining high CO2 package and in-package cold plasma (IPCP) treatments on the quality and safety of raw chicken breast meat. Non-inoculated samples and samples inoculated with Campylobacter jejuni and Salmonella Typhimurium were packaged in 0, 30, 70, or 100% CO2 (with make-up gas N2) and treated with IPCP at 70 kV for 3 min. Ozone formation, microbial counts, drip loss, pH, and color were measured. There was no interaction effect between high CO2 package and IPCP on microbial counts, drip loss, and color measurements. IPCP reduced spoilage microbial growth by 0.43 log (from 7.00 log to 6.57 log, P = 0.033) and C. jejuni populations by 0.67 log (from 4.82 log to 4.15 log, P < 0.001) on meat surface but did not affect S. Typhimurium (P = 0.206). Increased CO2 in packages had more effect on spoilage microbial growth (more than 1.5 log from 8.08 log to 6.35 log, P < 0.001) and S. Typhimurium populations (more than 0.5 log from 4.94 log to 4.39 log, P = 0.004) than IPCP but did not affect C. jejuni (P = 0.163). IPCP resulted in increases in changes in L* by 1.67 units (0.70 versus 2.37, P = 0.016) and a* values by 0.56 units (0.73 versus 1.29, P < 0.001) and decreases in b* values by 0.91 units (0.46 versus -0.45, P = 0.015). High CO2 levels caused increases in changes in L* values by 4.35 units (-0.82 versus 3.53, P < 0.001) with no effects on a* and b* values (P > 0.05). Data demonstrate that there are no combined effects by high CO2 package and IPCP on meat quality and safety of raw chicken breast meat under our experimental conditions. Either high CO2 package or IPCP can retain microbial quality and safety, even though they may cause changes in appearance of stored chicken breast meat.

Genomic tailoring of autogenous poultry vaccines to reduce Campylobacter from farm to fork

Campylobacter is a leading cause of food-borne gastroenteritis worldwide, linked to the consumption of contaminated poultry meat. Targeting this pathogen at source, vaccines for poultry can provide short-term caecal reductions in Campylobacter numbers in the chicken intestine. However, this approach is unlikely to reduce Campylobacter in the food chain or human incidence. This is likely as vaccines typically target only a subset of the high genomic strain diversity circulating among chicken flocks, and rapid evolution diminishes vaccine efficacy over time. To address this, we used a genomic approach to develop a whole-cell autogenous vaccine targeting isolates harbouring genes linked to survival outside of the host. We hyper-immunised a whole major UK breeder farm to passively target offspring colonisation using maternally-derived antibody. Monitoring progeny, broiler flocks revealed a near-complete shift in the post-vaccination Campylobacter population with an ~50% reduction in isolates harbouring extra-intestinal survival genes and a significant reduction of Campylobacter cells surviving on the surface of meat. Based on these findings, we developed a logistic regression model that predicted that vaccine efficacy could be extended to target 65% of a population of clinically relevant strains. Immuno-manipulation of poultry microbiomes towards less harmful commensal isolates by competitive exclusion, has major potential for reducing pathogens in the food production chain.

Assessment of water relaxometry of meat under different ageing processes using time domain nuclear magnetic resonance relaxometry

This study assessed water relaxometry of beef exposed to different ageing techniques by examining the inner and surface regions using time-domain nuclear magnetic resonance (TD-NMR) relaxometry. Beef strip loins were aged under vacuum (Wet), under vacuum using moisture absorbers (Abs), under vacuum using moisture absorbers and with mechanical tenderisation (AbsTend), or without any packaging (Dry). The ageing technique significantly influenced various meat parameters, including dehydration, total loss, and the moisture content of the meat surface. The transverse (T2) relaxation times provided a more sensitive indicator of the changes in meat water relaxometry than the longitudinal (T1) relaxation times. The Dry samples exhibited distinct differences in the T2 signals between the surface and inner regions of the meat. In particular, for the inner region, there were significant differences in signal areas between the Wet and Dry samples, and the Abs and AbsTend samples were positioned closely together between the Dry and Wet samples. The principal component analysis supported these findings: it indicated some differentiation among the ageing techniques in the score plot, but the differentiation was more pronounced when analysing the surface region. Additionally, there was a strong correlation between dehydration and the T2 values, leading to a clustering of the samples based on the ageing technique. The overlap between the Abs and AbsTend samples, situated between the Dry and Wet samples, suggests the potential of these treatments to produce meat with properties that are intermediate to Wet and Dry meat. Furthermore, tenderisation did not lead to greater dehydration.

Lamb meat colour is minimally affected under reduced oxygen concentration in modified atmosphere packaging

This study investigated how modified atmosphere packaging (MAP) with lower oxygen concentrations affects meat surface redness compared to standard 80% oxygen MAP for sheepmeat. Colour measuring instruments assessed redness (oxymyoglobin to metmyoglobin ratio and a*) in M. longissimus lumborum (loin) and M. semimembranosus (topside) from 50 Merino lambs. After 5 or 20 days of vacuum storage, meat samples were re-packaged into one of five MAP treatments (0, 20, 40, 60, or 80% oxygen), and colour was measured after 2, 6, or 10 days of retail display. Decreasing oxygen from 80% to 40% showed no negative impact on loin redness during retail display. Topside samples under 40% oxygen exhibited lower oxy/met values than 80% oxygen MAP at 2 and 6 days, with no difference after 10 days. This finding highlights the potential to reduce MAP oxygen content to 40% without compromising surface redness, potentially mitigating adverse effects on eating quality.

Development of a rhodamine-based fluorescent probe for ATP detection for potential applications in meat freshness assessment

Adenosine triphosphate (ATP) plays a vital role in physiological processes and is an essential indicator of microbial content in food. Herein, a new sensitive, rapid and water-soluble probe for ATP detection was developed. Rhodamine B and pentaethylenehexamine were employed to design and synthesise the probe rhodamine-pentaethylenehexamine (RP) for selective ATP detection. The synthesised probe RP was characterized using Fourier transform infrared, NMR and dynamic light scattering size distributions. Upon the addition of ATP, the probe exhibited a distinct change in fluorescence intensity, with fluorescence emission at 580 nm. A linear relationship was observed between fluorescence intensity and ATP concentrations at 0–50 μmol/L, with a limit of detection of 10.97 × 10−9 mol/L. The results of the zeta potential and molecular dynamics simulation demonstrated that the detection mechanism of the probe RP is associated with the electrostatic adsorption interaction between the multi-positively charged sites of RP and the negatively charged triphosphate structure of ATP. Our study provides new insights into improving charge site identification in small molecule detection. Furthermore, the successful detection of ATP on meat surfaces indicates that RP has the potential to assess meat freshness.

Preventing Microbial Growth in Game Meat by Applying Polyphenolic Extracts from Olive Mill Vegetation Water.

We studied the efficacy of different formulations of polyphenol extracts (mainly containing hydroxytyrosol and tyrosol) from olive mill vegetation water on the microflora on the surfaces of game meat cuts with high or low initial bacterial loads. Meat with a high microbial load (>5 Log cfu/g; mean value = 6.83 ± 0.45 standard deviation) was immersed for 10 or 60 sec into 25% and 10% solutions of microencapsulated freeze-dried and non-encapsulated polyphenolic extracts. Aerobic colony, Enterobacteriaceae, Pseudomonas spp., and lactic acid bacteria counts were determined on treated samples compared to controls after 7 days of storage (in vacuum-packed conditions at +3 °C). Significant differences were registered only for aerobic colony count for a 10% liquid extract treatment (0.64 log reduction). In contrast, the dipping or immersion of game meat with low initial microbial loads (<5 Log cfu/g; mean value = 3.58 ± 0.72 standard deviation) in 10% solutions of the polyphenol extracts effectuated significant reductions in all bacteria counts (p < 0.002) at 7 and 14 days of storage for different extracts, independently from the application methods. The use of the extracts to inhibit bacterial growth in game meat should only be considered if a good hygienic baseline is guaranteed.

The Study of Increasing Shelf-Life of Meat by Using Nanocellulose-Chitosan Composite Film Obtained from Agricultural By-Products

Background: This research was conducted to design a bionanocomposite film for meat packaging with regard to environmental aspects. Methods: Cellulose nanoparticles (CNPs) were used as nano-reinforcing factors were generated using non-edible agricultural by-products. The bionanocomposite film which was recently developed contains CNPs and chitosan (CS); then, the nanocomposites were explored via SEM, FTIR, agar disc diffusion tests and X-ray crystallography (XRD). Finally, the film was used to pack meat pieces. Results: Investigation of the morphological and physical reports of the solid films indicated that the CNPs are well scattered in bionanocomposite film. The addition of CNPs within a CS improved Young’s modulus by about 12135% and the tensile strength by 583%. In addition, XRD photographs indicated that CNP peak appeared after being added to CS context. Antimicrobial activity demonstrated that nanocomposites exerted restrictive effect on Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus bacteria. Using CS-nanocellulose composite as a packing film on meat surface leads to decreasing bacteria growth compared to nylon packing materials at 4˚C after 8 days of storage. Conclusion: Findings indicated that the recently designed CNP-CS films are a better replacement for common food packaging substances.

Driving forces shaping the microbial ecology in meat packing plants.

Meat production is a complex system, continually receiving animals, water, air, and workers, all of which serve as carriers of bacteria. Selective pressures involved in different meat processing stages such as antimicrobial interventions and low temperatures, may promote the accumulation of certain residential microbiota in meat cutting facilities. Bacteria including human pathogens from all these sources can contaminate meat surfaces. While significant advancements have been made in enhancing hygienic standards and pathogen control measures in meat plants, resulting in a notable reduction in STEC recalls and clinical cases, STEC still stands as a predominant contributor to foodborne illnesses associated with beef and occasionally with pork. The second-and third-generation sequencing technology has become popular in microbiota related studies and provided a better image of the microbial community in the meat processing environments. In this article, we reviewed the potential factors influencing the microbial ecology in commercial meat processing facilities and conducted a meta-analysis on the microbiota data published in the last 10 years. In addition, the mechanisms by which bacteria persist in meat production environments have been discussed with a focus on the significant human pathogen E. coli O157:H7 and generic E. coli, an indicator often used for the hygienic condition in food production.

Reduction of Campylobacter jejuni contamination by using UVA-LED and sodium hypochlorite on the surface of chicken meat.

Campylobacter jejuni causes gastroenteritis in humans and is a major concern in food safety. Commercially prepared chicken meats are frequently contaminated with C. jejuni, which is closely associated with the diffusion of intestinal contents in poultry processing plants. Sodium hypochlorite (NaClO) is commonly used during chicken processing to prevent food poisoning; however, its antimicrobial activity is not effective in the organic-rich solutions. In this study, we investigated the potential of a new photo-disinfection system, UVA-LED, for the disinfection of C. jejuni-contaminated chicken surfaces. The data indicated that UVA irradiation significantly killed C. jejuni and that its killing ability was significantly facilitated in NaClO-treated chickens. Effective inactivation of C. jejuni was achieved using a combination of UVA and NaClO, even in the organic-rich condition. The results of this study show that synergistic disinfection using a combination of UVA and NaClO has potential beneficial effects in chicken processing systems.

Stochastic inactivation evaluation of foodborne pathogens during ohmic heating of poultry meat

Abstract The objective of this study is to stochastically assess the inactivation probabilities of four common foodborne pathogens (Listeria, Salmonella, Escherichia coli, and Campylobacter) in chicken meat during ohmic heating (OH) in a salt solution. A mechanistic model was used to accomplish this, coupling heat transfer, laminar fluid flow, and the electric field, and solved numerically using COMSOL Multiphysics® v5.6. The 3D model represented 1000 particles randomly placed on the meat’s surface to determine the 7-log reduction of bacterial load probability. These particles are virtual representatives of bacterial colonies in the model. The influence of uncertain input parameters (specific heat capacity and electrical conductivity) and OH conditions (salt concentration of the heating medium, applied voltage, and heating time) was explained using logistic regression. The same analysis was repeated for the slowest heating point of chicken meat, as well. According to the findings, cold spots are observed at the corners of the meat piece during OH, requiring additional attention to the meat surface temperature to prevent under-processing. Sensitivity analysis revealed that the applied voltage and brine concentration are the main factors affecting the inactivation probabilities of pathogenic bacterial cells on the chicken meat surface. Salmonella and Listeria may require higher electrical conductivity of chicken meat and longer processing times. The developed model enables predicting inactivation probabilities of microorganisms that can be found on the outer surface by measuring the core temperature of the meat. However, especially for bacteria with higher heat resistance, it is better to consider the cold spot temperature found in the corners of the food material during OH.

Assessment of the bacteriological qualities of meat and contact surfaces in markets in Abia State, Nigeria

Background: Microbial contamination of meat comes from external sources during cutting, handling, and processing of the meat. This study was carried out to assess the bacteriological qualities of meat and contact surfaces in markets in Abia State, Nigeria. Methods: This research involved the use of a Hazard Analysis Critical Control Point (HACCP) checklist to investigate the sanitation and hygiene practices of meat sellers and a laboratory study of red and white meat, water, and meat-contact surface samples. A total of 425 meat samples collected from 425 meat sellers from some randomly selected markets in Abia State were used for the study. There were also 20 water samples, 22 samples from table surfaces, 22 samples from knife surfaces, and 14 samples from transport vehicles. The multistage simple random sampling technique through balloting was employed to determine communities/markets for the study. Samples for the study were collected and analyzed using standard microbiological techniques such as culturing and the bacteria were enumerated and identified using biochemical and chemical tests. Results: The prevalent bacterial isolates include Staphylococcus sp (78.80%), Bacillus sp (73.17%), Enterococcus sp (64.00%), Escherichia coli (62.11%), Salmonella sp (62.11%), Klebsiella sp (51.29%), Micrococcus sp (44.94%) and Campylobacter sp (43.52%). SPSS analysis using the one-way ANOVA showed no significant difference (p &gt; 0.05) in bacteria isolated from markets in the three Senatorial Zones of the State. Staphylococcus sp was isolated in 61.11% of the tables, 50.00% of vehicles, 41.67% of knives and 46.32% of water; Salmonella sp was isolated in 47.22% of the tables, 36.11% of vehicles, 30.56% of knives and 43.85% of water; Bacillus sp was isolated in 41.67% of the tables, 44.44% of vehicles, 33.33% of knives and 23.70% of water; Campylobacter sp was isolated in 27.78% of the tables, 25.00% of vehicles, 30.56% of knives and none in water. There was no significant difference (p &gt; 0.05) in bacteria isolated from the contact surfaces and water from the markets in the three zones of the State. Conclusion: The bacteriological quality of meat in markets in Abia State could be said to be poor due to the isolation of Indicator bacteria such as E, coli, Salmonella, and Campylobacter from the studied meat samples. The presence of E. coli in the studied meat samples is an indicator of feacal contamination and a red alert for the Public health sector. It is recommended that meat sellers undergo proper training and regularly update their knowledge of meat safety.

Influence of Ageing Time and Method on Beef Quality and Safety.

The effectiveness of dry ageing with regard to retaining meat quality is still subject to debate. At 4 d post mortem, samples of boneless strip loins were excised from young Charolais carcasses and then stored for a further 26 d in a cooler, either vacuum-packaged (VP) or dried-aged (DA). Loin samples were also dissected 7 d post mortem as a control treatment (CT). Chemical, instrumental and microbiological data (n = 18) were determined in longissimus dorsi and underwent ANOVA to estimate the differences in the ageing fixed factor split into two orthogonal contrasts: control vs. aged and VP vs. DA. Ageing loss (both surface dehydration and water purge) was greater in DA compared to VP samples, resulting in the lowest moisture content and highest crude protein and fat percentage in DA loins. The ageing method did not affect meat surface colour, except for redness, which had the lowest value in DA samples. Meat tenderness improved a similar amount following both VP and DA ageing treatments. Compared to the control, prolonged ageing raised both the peroxide value and the total microbial count, especially in DA samples, though both remained within the recommended limits. In summation, both ageing methods improved beef meat tenderisation, preserving its shelf life.

&lt;em&gt;Brochothrix thermosphacta&lt;/em&gt; as a microbiological indicator in determining the expiration date of meat products

Microbial spoilage of food products leads to significant losses with negative social and economic consequences. In order to better control contamination and microbiological spoilage of food products, a new GOST P 70354-22 has been introduced. Meat and meat products. General requirements and procedure for testing to justify expiration dates (publication date 09/29/2022). Great importance is attached to the identification and quantification of the additional microbiological indicator Brochothrix termosphacta in meat, meat and meat-containing products packed using vacuum or modified gas atmosphere. Brochothrix sp. may become the dominant type of meat spoilage in MHA packaging and vacuum packed in the presence of sufficient oxygen. Brochothrix causes mucus and stickiness of the meat surface, unpleasant odors. Brochothrix also causes mucus and stickiness on the meat surface. GOST P 70354-22 describes a method for detecting and counting the number of bacteria Brochothrix sp. For their cultivation, a dense selective medium STAA was proposed. It allows you to isolate, identify and determine the amount of Brochothrix in samples. The technique described in GOST P 70354-2022 was tested. According to the results of cultivating primary crops, we observed the growth of characteristic small, round, shiny, gray-white colonies of Brochotrix on the surface of a special medium. The studied bacteria were oxidase-negative and catalase-positive.

Antibacterial film based on κ-carrageenan with benzyl isothiocyanate-β-cyclodextrin inclusion complex: Characterization and application in chicken preservation

To effectively utilize the potent antibacterial capacity of benzyl isothiocyanate (BITC), attempts have been made to apply it in the natural biopolymeric film by solving its high volatility. In this study, we encapsulated BITC in the carrier β-cyclodextrin (βCD) to form an inclusion complex to protect BITC from volatilization and then introduced the complex to κ-carrageenan (KC) to fabricate an antibacterial food packaging film. The addition of the BITC-βCD complex enhanced the storage modulus and promoted a denser network structure formation for KC hydrogel by rheological measurements and microstructure observations, respectively. In terms of antibacterial capacity, BITC-βCD-KC film displayed favorable antibacterial potential against both Staphylococcus aureus and Listeria monocytogenes after co-incubation for 18 h, with the inhibition zone diameters of 25.7 mm and 16.7 mm, respectively. As an active packing material, the BITC-βCD-KC film exhibited a sustained inhibition effect against the proliferation of these two bacteria on the chicken meat surface at 25 °C. Moreover, the chicken breasts packaged with BITC-βCD-KC film had a total viable count of 4.7 Log CFU/g, obviously lower than that of the unpackaged sample (9.8 Log CFU/g) after storage at 4 °C for 8 days. These results suggested that the KC film with the BITC-βCD inclusion complex might have promising potential as an antibacterial food packaging material for food preservation.

Proteomic analysis of Staphylococcus aureus exposed to bacteriocin XJS01 and its bio-preservative effect on raw pork loins

Antibacterial mechanism of bacteriocins against foodborne S. aureus is still to be explored, particularly in proteomics, and a deep and comprehensive study on application of bacteriocins for preservation of raw pork is required. Here, proteomic mechanism of Lactobacillus salivarius bacteriocin XJS01 against foodborne S. aureus 2612:1606BL1486 (S. aureus_26) and its preservation effect on raw pork loins stored at 4 °C for 12 days was investigated. The results showed that 301 differentially abundant proteins (DAPs) were identified between XJS01-treated and -free groups (control group) using Tandem mass tag (TMT) quantitative proteomics technology, which were primarily involved in amino acids and carbohydrate metabolism, cytolysis, defense response, cell apoptosis, cell killing, adhesion, and oxygen utilization of S. aureus_26. Bacterial secretion system (SRP) and cationic antimicrobial peptide resistance may be key pathways to maintain protein secretion and counteract the deleterious effects on S. aureus_26 caused by XJS01. In addition, XJS01 could significantly improve the preservation of raw pork loins by the evaluation results of sensory and antibacterial activity on the meat surface. Overall, this study showed that XJS01 induced a complex organism response in S. aureus, and it could be potential pork preservative.

Shelf-life of sheep &lt;i&gt;arrosticini&lt;/i&gt; packaged in protective atmosphere

The aim of this study was to evaluate the shelf-life of pre-packaged sheep arrosticini produced in a factory located in northern Italy. Samples were divided into two series and packaged in modified atmosphere with specific gas mixtures: conventional (C: 35% O2/15% CO2/50% N2) and experimental (E: 30% CO2/70% N2). All the samples were stored at 4°C for 10 days and subjected, after 5, 8 and 10 days (t5, t8, t10), to triplicate microbiological and chemical-physical (pH, total volatile basic nitrogen, thiobarbituric acid reactive substances) analyses. At the same time, the colorimetric analysis and a sensorial evaluation were carried out (pack tightness, presence of color or odor alterations), assigning a discrete score from 0 to 5. The samples showed initial total bacterial counts close to 5 Log CFU/g: these values gradually increased during storage, exceeding the threshold of 8 Log CFU/g in the C series; lower values were detected in the E series. A similar trend was highlighted for Enterobacteriaceae, with initial loads of about 3 Log CFU/g and an increase until t10, reaching values higher than 6 Log CFU/g in the C series and close to 5 Log CFU/g in the E series (P=0.002). E. coli also showed a similar trend, although with values approximately 1 Log lower than Enterobacteriaceae. Pseudomonas spp. showed initial counts close to 4.5 Log CFU/g, with a different increase in the C series (6.5 Log CFU/g at t10) and the E series (4.95 Log CFU/g) (P=0.006). The higher growth in the C series was also observed for lactic acid bacteria, with an increase from 3 to 5 Log CFU/g (3.8 Log CFU/g in the E series P=0.016). The other microbiological parameters showed very low counts and, in most cases undetectable counts (&lt;2 Log CFU/g) for the entire period considered. The initial values obtained from the measurement of the colorimetric indices were within the norm for this type of product: however, starting from t5, lower values of red index and lightness in the E series were measured, with an evident greying of meat surface. The results of the sensory evaluation indicated that the product showed optimal sensorial characteristics up to 8 days of shelf-life in the C series, while the use of an oxygen-free atmosphere, despite having a moderate inhibiting effect on the microbial populations, has led to an early modification of the product (5 days of storage), due to the presence of superficial greyish areas. The microbiological characteristics of arrosticini strictly depend on the hygienic conditions of slaughtering and production; even in optimal situations, the product is particularly perishable, and requires careful management of storage temperatures and times, to maintain its quality characteristics.

Bacteriological quality assessment of poultry chicken meat and meat contact surfaces for the presence of targeted bacteria and determination of antibiotic resistance of Salmonella spp. in Pakistan

During the slaughtering process, the meat product cross-contaminates with the surrounding contact surfaces. This study aimed to assess the level of microbial contamination of poultry chicken meat and contact surfaces at poultry slaughterhouses in the Hyderabad and Jamshoro districts of Pakistan. A total of 38 slaughter shops were selected, and from each shop, three types of samples were collected. All the samples were assessed for the presence of three microbes, Salmonella, Shigella, and E. coli by using some culture-based techniques, and for Salmonella, antibiotic resistance was also determined. Results revealed that Shigella was present in 86.8% of knives, 94.7% of chopping board and 97.3% of meat samples. While, the E. coli was present in 86.8% of knife, 97.3% of chopping board, and 97.3% of meat samples. Salmonella was detected in 97.3% of knives, 92% of chopping boards, and 97.3% of meat samples. All the isolates of Salmonella exhibited resistance to one or more antibiotics. Resistance to ampicillin, gentamicin, cefotaxime, erythromycin, neomycin, streptomycin, and sulphamethoxazole were evident in 91.7%, 25.6%, 32.1%, 40.3%, 33.9%, 34.8%, and 52.2% respectively. However, only 6.4% of isolates showed resistance to azithromycin (6.4%), and none of them showed resistance to ceftazidime. Moreover, 61.4% (67/109) of isolates were multiple drug-resistance (MDR). A high prevalence of Salmonella, Shigella, and E. coli in meat and on contact surfaces can be considered a major risk for human health. It is vital to continue developing strategies to limit the danger of foodborne diseases in slaughtering facilities.

Delmopinol hydrochloride inhibits Campylobacter jejuni on skinless poultry meat, stainless steel and high-density polyethylene food contact surfaces.

Delmopinol hydrochloride (delmopinol) is a cationic surfactant that is effective for treating and preventing gingivitis and periodontitis. This study evaluated the effectiveness of delmopinol for reducing attachment of Campylobacter jejuni to chicken meat, stainless steel and high-density polyethylene (HDPE). These test materials were spot-inoculated with a C. jejuni culture. After 10min, samples were sprayed with 0.5% or 1.0% delmopinol, 0.01% sodium hypochlorite, or distilled water. After a 1, 10, or 20min contact time, samples were rinsed which were serially diluted onto Campy-Cefex Agar. For additional samples, solutions were applied before inoculation with C. jejuni. Cultures remained undisturbed for 1, 10, or 20min. Samples were then rinsed and plated as above. When C. jejuni was inoculated before treatments, 1% delmopinol application led to mean log reductions of 1.26, 3.70, and 3.72 log cfu ml-1, greater than distilled water alone, for chicken, steel and HDPE respectively. When C. jejuni was inoculated after spray treatments, 1% delmopinol reduced C. jejuni by 2.72, 3.20, and 3.99 mean log cfu ml-1 more than distilled water for chicken, steel and HDPE respectively. Application of 1% delmopinol, resulted in a significantly (P<0.05) greater log reduction than a 0.01% sodium hypochlorite or distilled water application.