Validation of parameters in HACCP verification using univariate and multivariate statistics. Application to the final phases of poultry meat production

For Hazard Analysis and Critical Control Points (HACCP) systems verification in food industries, the selection of parameters that offer significant information about control system at each production stages is necessary. Total Count (TC), Pseudomonas (PS), Enterobacteriaceae (EB) and Staphylococcus aureus (ST) are organisms frequently measured on carcasses at slaughters. Their inclusion in HACCP system can be assessed by means of statistical techniques. Univariate and multivariate statistical methods are of great importance in order to identify most useful variables. In this study the use of these microbiological parameters in verification of refrigeration, and cutup and packaging operations has been evaluated. It has established the usefulness of these variables using statistical techniques. It makes clear the most discriminant effect of EB and TC to establish differences between the stages studied in this process.     

The influence of acid and alkaline treatments on pathogens and the shelf life of poultry meat

A study was carried out to determine the influence of acid and alkaline treatments on pathogens and the shelf life of poultry meat. The following acid and alkaline substances were used: 1% lactic acid, (Purac^R), a 1% formulation of active constituents (sugars, foodstuff phosphates, ascorbic/isoascorbic acid or their inorganic salts) with lactic acid as activator (Glutamal bioactive^R) and 10% trisodium phosphate (TSP). A total of 360 poultry carcasses were collected from a poultry processing plant and subjected to spray treatments at a pressure of 300 kPa and dipping treatments using the acids and alkali. Water was used as control. The carcass rinse method was used as the method of sampling. The microbiological data obtained were subjected to statistical analyses using the multifactor analysis of variance (ANOVA). Sensory evaluations were conducted using a seven-member panel to determine the acceptability or otherwise of the treated carcasses. Mean log₁₀ reductions (cfu/ml) achieved, based on the different treatments, modes of treatment and days of storage were between 0.4 and 2.5 for APC; 0.5 and 2.7 for Enterobacteriaceae; 0.2 and 2.4 for Pseudomonas, and 0.2 and 1.1 for Lactobacillus. The dipping treatment gave the best overall reduction effect. About 60% of the carcasses examined (day 0, only) were positive for salmonella. The sensory evaluations recorded high acceptability scores. The findings show that acids and alkaline substances are viable tools for the decontamination of poultry carcasses.     

Effect of extending processing plant operating time on the microbiological quality and safety of broiler carcasses

In Australia, increased consumer demand for chicken meat and socioeconomic pressures have forced poultry operations to extend plant operating time with delayed spin-chiller emptying and cleaning to maximise water use efficiency. There are concerns that these measures may compromise the microbiological quality and safety of the product. Therefore, the objective of this trial was to determine the microbiological status of broiler carcasses collected hourly during 24 h and 48 h continuous chiller operation within a three week period (total n = 196). Carcass rinses were analysed for total viable count, Escherichia coli and Campylobacter spp. counts, and Salmonella prevalence. Corresponding spin-chiller parameters (pH, oxidation-reduction potential [ORP], core temperature and HOCl concentration) were recorded. There was no statistically significant difference (P > 0.05) in bacterial populations and spin-chiller parameters when various sized chickens were processed. Therefore, the microbiological data and consequent quality were shown to be statistically equivalent between carcasses sampled from 24 h to 48 h continuous processing using a fully automated (water temperature, pH and chlorine control) spin-chiller. However, improvements to processing, including rehang and scald hygiene, and weight-specific hypochlorous acid concentrations, should be researched in order to further reduce bacterial contamination.     

Application of an electronic nose for quality assessment of modified atmosphere packaged poultry meat

The applicability of an electronic nose for the quality control of modified atmosphere (MA) packaged broiler chicken cuts was evaluated in different temperature regimes. The electronic nose results were compared with those obtained by microbiological, sensory and headspace GC analyses. The electronic nose could clearly distinguish broiler chicken packages with deteriorated quality from fresh packages either earlier than or at the same time as the sensory quality deteriorated. Concerning the microbiological quality, the counts of Enterobacteriaceae and hydrogen sulphide-producing bacteria were most consistent with the electronic nose results. The results indicated that the electronic nose was capable of detecting even early signals of spoilage in MA packed poultry meat.     

The establishment of critical control points at the washing and air chilling stages in poultry meat production using multivariate statistics

The selection of control points is one of the most important steps in the design of a Hazard Analysis and Critical Control Points (HACCP) system. Total Count, Pseudomonas and Enterobacteriaceae are microorganisms frequently analyzed on carcasses in slaughterhouses. Its usefulness can be assessed by means of univariate and multivariate statistical methods. In this study, the use of these microbiological parameters for verification of the effect of the stages of washing with pressurized water and air chilling has been evaluated. It makes clear that multivariate statistics appears as a valuable tool to check which points and stages of the process must be controlled, demonstrating that the washing stage produces significant decreases in contamination (so it must be considered a CCP). The air chilling stage maintains the decrease in the contamination as the carcasses come out of the washing process. This is due to the control of temperature under adequate limits. The chiller air temperature would be considered a CCP in a HACCP system.     

Variability of Escherichia coli and Enterobacteriaceae counts on pig carcasses: A systematic review

BackgroundIndicator bacteria are considered an interesting target for microbiological analysis in order to obtain information about the hygiene of processes and products. Quantitative analysis targeting indicator bacteria offers several advantages over pathogenic bacteria since indicator bacteria prevalence and counts are higher, and their distribution is more homogeneous, than pathogens. However, although microbiological criteria addressing indicator bacteria are already in place in industrialised countries such as the EU and US, information on factors affecting their counts on carcasses at slaughter is scattered.ObjectivesThe aim of this review was to provide valuable information about the variability of indicator bacteria along the pig slaughterline, and to suggest suitable means for the implementation of GMP (Good Manufacturing Practices) and process hygiene in pig slaughterhouses.ConclusionsAlong the slaughterline, scalding and chilling stages effectively reduce both Escherichia coli and Enterobacteriaceae counts on pig carcasses and have to be considered in the implementation of HACCP systems. Surface pasteurisation under experimental slaughter conditions was also effective; in contrast, washing did not reduce microbial contamination on pig carcasses. Evisceration was confirmed as a key contamination point, in particular regarding Enterobacteriaceae, but it has been suggested that bacterial load can be controlled by anal plugging if it is performed according to good manufacturing practices (GMP).     

Characterization of wheat-based biscuit cooking process by statistical process control techniques

A commercial wheat-based biscuit cooking process was characterized using statistical process control (SPC) techniques. These techniques included histograms, analysis of means (ANOM), control charts, process capability studies and Gauge Repeatability and Reproducibility (Gauge R&R). The production variables studied included raw material variables (wheat protein and moisture content) and product variables (biscuit breaking strength, moisture content and thickness of biscuit). The plant studied has three independent production lines, so product variables were analysed separately for each line. ANOM indicated that several process means were significantly different (α=0.05) from the grand mean (breaking strength line 3, product moisture content line 3 and thickness of biscuit in all lines). Control charts indicated that some observed variables were not in statistical control (wheat protein and moisture content, breaking strength line 3 and thickness of biscuit for lines 1–2). Results from capability studies showed that all observed variables except wheat moisture content were not capable. Notably, there was a large variation in the thickness of biscuit. Gauge R&R suggested that the measurement system used was inadequate, contributing to the variation found in the process characterization. Initial investigation of the relationship between raw material variables and product variables in each line found no correlation.     

Example of a microbiological criterion (MC) for verifying the performance of a food safety control system: Campylobacter Performance Target at end of processing of broiler chickens

New Zealand has focused on improving the food safety control systems for slaughter and dressing of broiler chickens in order to get a reduction in Campylobacter levels on carcasses at the end of primary processing. Each processor decides which good hygienic practice-based and hazard-based control measures to apply. Codex guidelines provide valuable information to assist with these decisions. To verify that the resulting control systems are effective, New Zealand established a microbiological criterion for Campylobacter which is applied after slaughter and dressing and initial chilling of broiler chickens. New Zealand calls this a regulatory Campylobacter Performance Target (CPT). Samples are tested by a direct plate enumeration method. Results are analysed using a “moving window approach” to aid data interpretation and decision-making. A “moving window limit” failure occurs when the log count for seven or more out of 45 samples in the moving window are greater than the established target of 3.78 log₁₀ cfu/carcass. If processors meet the “target” this verifies that their process is under control. If processors fail the “target” they are expected to take corrective actions to restore control. If the processor's actions do not restore control in a timely fashion, the regulator applies further controls. This example is based on actual data from New Zealand poultry processers. The application of this microbiological criterion is flexible and other countries may be able to adapt this approach to suit their particular circumstances.     

Water reuse in a shrimp processing line: Safety considerations using a HACCP approach

The large consumption of water involved in food manufacturing is prompting food processors to optimise the use. Treating and reusing or recycling water within the food plant results in substantial reduction of water use and wastewater production and discharge. If implemented, water reuse should be integrated into existing HACCP programs, and HACCP plans specifically addressed to the actual reuse should be elaborated. This paper evaluates the microbiological safety issues associated with water recycling during the production of shrimps (Pandalus borealis) in brine, and it indicates how the hazards may be effectively controlled using a HACCP approach. Following these procedures, process water recovered from peeling during shrimp processing and treated by means of reverse osmosis could be recycled within the same food unit operation.     

Implementation and effectiveness of the HACCP and pre-requisites in food establishments

The aim of this paper was to identify the most important weaknesses in the implementation and effectiveness of the pre-requisites and HACCP found in food establishments. To cover these objectives, official control audits of the manuals and their implementation in 1350 small and 66 medium size organizations: restaurants, hotels and cafeterias in one area of the Valencian region (Spain) were carried out from 2007 to 2010. The microbiological quality of 1054 ready-to-consume dishes was also evaluated as an indicator of the effectiveness of the control at Critical Control Points. The results showed that the main deficiencies in the implementation of the pre-requisites and HACCP were found in conditions and structural design followed by hygiene & cleaning. Moreover, the analysis of Listeria monocytogenes in dishes at the time of consumption shows that 99.6% were of good microbiological quality. This indicates that in relation to this hazard, the implementation of safety management systems in the majority of the food establishments was effective. These results demonstrate the crucial role played by official control to ensure the welfare of consumers and how it facilitates continuous improvement in the safety management of these businesses.     

Escherichia coli and Enterobacteriaceae counts on poultry carcasses along the slaughterline: A systematic review and meta-analysis

BackgroundThe slaughtering process consists of a highly coordinated system of different operations and is of critical importance for meat hygiene. The evaluation of the impact of different stages on bacterial counts is useful to monitor carcass contamination and to improve the hygiene of different stages. Escherichia coli and Enterobacteriaceae are considered an interesting target for microbiological analysis.ObjectivesThe aim of this review was to summarize literature data about the influence of slaughter stage on E. coli and Enterobacteriaceae counts along the poultry slaughterline.ResultsSystematic review of the available literature and the meta-analysis of the data collected revealed that scalding resulted in a significant reduction of E. coli counts. Washing and chilling were able to decrease E. coli counts in a statistically significant way; however, the observed reductions were of no practical importance. Enterobacteriaceae were reduced only by defeathering and washing but no practical significance was observed. None of the other stages of the slaughterline resulted in significant changes of indicator bacteria counts.Conclusions and implicationsInformation provided would be useful to suggest suitable ways for the implementation of processes hygiene in poultry slaughterhouses in particular GMP (Good Manufacturing Practices) and HACCP through the identification of suitable CCPs.     

Prevalence of Listeria spp. at a poultry processing plant in Brazil and a phage test for rapid confirmation of suspect colonies

Sites and occurrence of Listeria contamination in an industrial poultry processing plant were investigated by sampling carcasses at varying stages of processing and testing the hands and gloves of food handlers as well as the chilling water used in the process. In the course of nine visits to a local processing plant we collected a total of 121 samples: 66 from carcasses, 37 from workers' hands and gloves and 18 from the water used for chilling. Except for the water samples Listeria was isolated at all sampling sites. The species most often isolated was Listeria innocua, which accounted for 28 of the 31 (90.3%) isolates. The frequency of Listeria in the chicken carcasses was similar at bleeding, defeathering and end of evisceration stages (33.3%), reduced during scalding (16.7%), and rose immediately after initial evisceration stage (50%) to peak after packaging (76.2%). The carcasses were contaminated by L. monocytogenes serotypes 1b and 1c only during packaging. The prevalence of Listeria spp. on workers' hands and gloves was 46% mostly with L. innocua (40.5%) followed by L. monocytogenes 1b (11.8%). Chilling water presented more than 100 ppm of chlorine, which could explain why the samples were negative to Listeria. As the contamination by Listeria in the carcasses progressively rose both in number, species and strains during processing it seems reasonable to conclude that those carcasses become contaminated at the processing level. Improvement and innovation measures to control bacteria in general at the processing plant level are necessary to effectively reduce final product contamination by L. monocytogenes. In the course of this work we introduced a bacteriophage susceptibility test to confirm suspected Listeria colonies which was able to reduce the time of analysis to a minimum of 30 h depending on the isolation technique employed.     

Role of government in HACCP audit: a Cuban perspective

Since 1992 the Ministry of Fishery Industry (MIP) through its Quality Assurance Directorate (DAC) began HACCP implementation works as a basis of its Quality Management System, meeting in this way requirements of its major importers and tailoring to changes in inspection and quality control activities that were taking part worldwide.According to the Minister's Resolution No. 344/1996, HACCP is mandatory for all activities carried out by all entities of MIP, whose activity is related to the manufacturing of fish products from catching operations to its placing in the market.HACCP assessment in fishery establishment is performed in different ways:

• •Submission of HACCP-based Quality Assurance Program (QAP) to DAC for validation. This draft of QAP is revised and returned with suggestions and remarks for its redrafting and new submission.
• •Supervisions performed by DAC and National Fishery Inspection Office (ONIP) specialists to end products, manufacturing process' stages and facilities to verify the compliance of regulations, procedures, cleaning and sanitizing procedures and quality specifications standards.
• •Verifications by means of microbiological, physical, chemical and sensory testing to end products at the reference laboratory requested by DAC
• •Cost/profit assessment of HACCP implementation in fishery establishments with the utilization of Prevention–Appraisal–Failure Model (PAF), according to a procedure developed at the `FAO's Economical Engineering Workshop applied to Fishery Industry, March 1997'.
• •As on January 1998, regulatory audits to HACCP-based QAPs began to be performed in fishery establishments, verifying compliance of applicable documentation (Quality Assurance Programs; Cleaning and Sanitizing Procedures, Working Operational Procedures, and so forth) using the `General Procedure for HACCP Audit's performance in fishery establishments' with a group of auditors made up by DAC specialists and ONIP officer inspectors.

For the development of these activities in force up to date, we relied on the collaboration and consultancy of FAO/DANIDA GCP/INT/609/DEN Project in national courses, exchange of experience exchange and training with Inspection and Quality Assurance Bodies of other countries and as a multiplying effect of these activities, the consultancy and training carried out by experts from DAC of MIP to inspectors and industry's technical staff.     

Microbiological risk assessment in the beverage industry

This paper illustrates some of the developments and considerations in the field of quantitative microbiological risk assessment, applying a beverage industrial model based on laboratory based experiments, process exposure assessment versus finished-product microbiological quality control. In laboratory experiments, the authors investigated the effect of chlorination on Klebsiella oxytoca and the efficacy of industrial water treatment was estimated by applying a mathematical model based on destruction kinetics. The quantitative risk assessment model took into account the input contamination level, the chlorine concentration and the residence time distribution in the chlorination tanks with their probability distribution and the probability of Klebsiella oxytoca detection in the treated water as a function of the input cell concentration was calculated by using Monte Carlo simulation. The model was validated in a Pilot Plant for a six month period and the linear relationship between the predicted and observed probability of Klebsiella-detection was characterized with a determination coefficient of R²=0.905.     

Prevalence and quantification of Campylobacter contamination on raw chicken carcasses for retail sale in China

The quantitative contamination load of Campylobacter on raw chicken carcasses at retail outlets in seven provinces and cities of China was determined. A total of 1587 carcasses over 12 consecutive months were sampled. The overall Campylobacter contamination rate was 45.1% and 19.8% of contaminated carcasses was higher in the load than 3.0 log₁₀CFU/g. The median load was 2.1 log₁₀CFU/g with 1.4 log₁₀CFU/g as the 25th percentile and 2.9 log₁₀CFU/g as the 75th percentile, respectively. Using logistic regression, it observed the significant provincial and monthly variations in prevalence, freshly slaughtered chicken carcasses (63.1%) were found to be 2.3 times higher compared to chilled carcasses (32.9%), while no statistical significance was observed in prevalence among chicken carcasses that had various packaging solution (P = 0.370) nor from different market types (P = 0.680) suggesting that possible cross-contamination had occurred during processing and transportation. The present study found that 52.1%, 59.9%, 2.9%, 8.8% and 8.3% of carcasses were contaminated with C. jejuni, C. coli, C. lari, C. fetus, and C. upsaliensis, respectively. A higher proportion of C. coli (45.4%) than C. jejuni (39.5%) were cultured from the contaminated carcasses and this finding was suggestive of a high degree of cross-contamination occurred not just among poultry products, but also with pork products before/at retail points in China. This study provided quantitative data suitable for a risk assessment model designed to evaluate useful intervention methods to facilitate a reduction in the risk of campylobacteriosis arising from the consumption of contaminated domestically produced chicken meat in China.     

PCR detection of Campylobacter sp. from turkey carcasses during processing plant in Iran

Turkey carcasses were sampled in one commercial poultry processing plant of Isfahan (Iran) to evaluate the contamination of carcasses to Campylobacter spp. along the processing plant by PCR method. A total of 348 samples were collected during six plants visit from May to December 2007. Campylobacter spp. were isolated from 62.1% (216 out of 348) of the samples. Out of 216 Campylobacter isolates, 175 (81.0%) were identified as Campylobacter jejuni and 41 (19.0%) as Campylobacter coli. The occurrences of Campylobacter spp. contamination after defeathering, evisceration and chilling were 75.9%, 77.6% and 32.8% respectively. The results indicate that the fecal recontamination of the avian skin occurred during defeathering and evisceration. However chilling process decreases Campylobacter spp. contamination of the turkey skin significantly.     

Hazard identification: from a quantitative to a qualitative approach

Hazard identification is a common step in the hazard analysis and risk-assessment processes. The fact that this step is shared between the two processes is creating some confusion about how they can be used in our food safety programs. Hazard analysis and risk assessment are fundamentally different and independent processes.Hazard analysis is a qualitative, local process conducted by a food plant's HACCP team. This process usually requires several weeks or months to complete. In contrast, risk assessment is a quantitative, global process in which a numerical degree of risk can be calculated for a particular hazard. It is usually conducted by a large consortium that includes regulatory, public health, academic, and industry participation. It is a longer process, typically requiring several months or years for completion.In hazard analysis, one major method for the identification of hazards consists of a review of the sensitive ingredients used in food production. Many food companies maintain sensitive ingredient lists for hazards such as Salmonella, Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, aflatoxin, allergens, etc. Another major method for the identification of hazards consists of an open-ended brainstorming process by the HACCP team, which in 1992 replaced the brief, formal hazard analysis process that was first used about 30 years ago. The limited number of questions considered in the formal process proved to be insufficient to address the needs of the food industry, which is continually dealing with new hazards, new products, new processes, new markets, and new regulations.HACCP systems are designed to control identifiable hazards. Additional hazards that may need to be included in HACCP plans include previously unknown hazards that are identified by epidemiological efforts, and “regulatory hazards” that are mandated in new food regulations.     

Reducing microbial counts on chicken and turkey carcasses using lactic acid

A 4% concentration of lactic acid, buffered to pH = 3.7, was applied by spraying directly after the inside-outside washer of a commercial chicken and a turkey production line with the aim of reducing microbial counts on the carcasses. Slight paling of the skin and slight greying of the leaf fat was observed on the carcasses but this was considered to be commercially acceptable. Microbial reductions varied with length of storage after killing, and after treatment with acid. For both chicken and turkey, there was a highly significant difference (p < 0.001) in aerobic plate counts between control and treated carcasses up to Day 9, but no difference on Days 13 and 16. The largest difference between the aerobic plate counts on control and treated carcasses was 2.1 log₁₀ cfu/g on chicken (Day 6) and 1.1 log₁₀ cfu/g on turkey (Day 9). The prevalence of Campylobacter on turkey carcasses on the day after slaughter was reduced significantly (p < 0.001) by the application of the acid. The results indicate that the application of lactic acid offers a method of reducing microbial counts on poultry and may have implications for shelf life and food safety.     

Prevalence and fluoroquinolones resistance of Campylobacter and Salmonella isolates from poultry carcasses in Rio de Janeiro,Brazil

To investigate the prevalence of Campylobacter and Salmonella in poultry carcasses in state of Rio de Janeiro, Brazil, 60 samples from 6 slaughterhouses were collected over a period of 6 months. A total of 82 Campylobacter isolates were obtained from twenty seven (45%) positive chicken carcasses, including 44 isolates (53.66%) of Campylobacter jejuni and 38 (46.34%) of Campylobacter coli. The identification of all strains was confirmed by PCR. Salmonella was isolated from 4 (6.67%) carcasses by conventional method and was detected in 5 (8.33%) of 60 chicken carcasses by PCR. Two Salmonella Albany and two Salmonella Typhimurium were identified. Antimicrobial susceptibility testing was primarily done by the disk diffusion method and later by assessing minimum inhibitory concentrations (MICs) against all the isolates. All the Campylobacter isolates were resistant to ciprofloxacin and enrofloxacin. It was observed high MIC values for enrofloxacin (64 μg/mL) in one C. jejuni and two C. coli strains, and for ciprofloxacin (≥128 μg/mL) in one C. jejuni and three C. coli strains. No Salmonella isolate was resistant to these antibiotics by both methods. These findings reveal a broad extent of fluoroquinolone resistance in Campylobacter isolates from chicken carcasses in Brazil and underline the need for prudent use of these antibiotics in poultry production to minimize the spread of fluoroquinolone resistant Campylobacter.     

Ratio between carcass-and skin-microflora as an abattoir process hygiene indicator

In two abattoirs, each slaughtering both cattle and pigs, 100 cattle and 100 pigs were randomly selected and sampled. From each animal, two samples were taken: a) immediately after sticking of bovines or stunning of pigs, approximately 2000 cm² hide (cattle) or 1500 cm² skin (pigs) areas were sponge-swabbed; and b) at the end of slaughter line but before chilling, the same areas on corresponding dressed carcasses were sponge-swabbed. In each swab-sample (400 in total), total viable count (TVC) and Enterobacteriaceae count (EC), as well as Escherichia coli O157 (in cattle) or Salmonella (in pigs) occurrence, were determined and used to assess process hygiene in the abattoirs. The results indicated that simply fitting mean TVC and/or EC on final carcasses into an acceptable, marginal or unacceptable process hygiene category (according to current microbiological EU process hygiene criteria) did not enable characterisation of each process with respect to its ability to reduce the transfer of incoming microbial loads (i.e. on skins) onto dressed carcasses. On the other hand, determining the ratio between mean TVC and/or EC on final carcasses and those on corresponding skins enabled more precise assessment of the hygiene of each abattoir process, as well as more reliable differentiation between abattoirs. On the other hand, occurrence of E. coli O157 in cattle or Salmonella in pigs (skins and/or carcasses), being dependant on varying factors including those on-farm/pre-abattoir, did not appear to be very useful for characterisation of the process hygiene but is valuable for the purposes of consumer exposure assessment and pathogen reduction.