bluuebunny/crossref_metadata_2025 huggingface dataset:
DETECTION OF SALMONELLAE IN CHICKEN AND FISH SAMPLES USING DNA PROBE
Authors: BANDEKAR J.R. , USSUF K.K. , NAIR P.M.
Published: April 2007

The use of DNA probes for rapid identification of foodborne pathogens is an emerging field. We have standardized a method for the detection of Salmonella in food samples by using a specific insertion sequence (IS‐200) of Salmonella chromosomal DNA as the probe. The procedure for colony hybridization, and washing conditions for the stringency were established. All the ten Salmonella strains, belonging to various serotypes tested were positive while 18 other bacterial cultures, mainly belonging to the family Enterobacteriaceae such as E. coli Shigella, Proteus etc., were negative in colony hybridization. The sensitivity of the detection was found to be 105 cfu using 32P‐labeled probe. We surveyed 16 chicken and 6 fish samples from local market using IS‐200 probe after preenrichment and selective enrichment. All the samples tested were found positive with DNA probe. The major strains of Salmonella isolated from these samples were S. gallinarum, S. typhimurium, S. enteritidis, S. choleraesuis and S. paratyphi A. These results were confirmed by standard Salmonella identification method.
LINKING MICROBIOLOGICAL CRITERIA FOR FOODS WITH QUANTITATIVE RISK ASSESSMENT
Authors: ROSE JOAN B. , HAAS CHARLES N. , GERBA CHARLES P.
Published: April 2007

The current annual risk of acquiring a foodborne disease in the United States is estimated at 2.7 × 10‐2. The risk of associated death is estimated at 3.7 × 10‐5. These represent a health care burden >$3 billion. Using a risk assessment model one can identify levels of microbial contamination which may be unacceptable in foods and appropriate controls needed to reduce these levels. Salmonella bacteria continue to represent a large percentage of the identifiable infections. A model developed from human dose‐response studies predicts the probability of infection for Salmonella at 7.5 × 10‐3 with exposure to a single CFU of the organism. Risks of severity (hospitalization), mortality, reactive arthritides, and mortality in the elderly are estimated at 3.1 × 10‐6, 7.5 × 10‐6, 1.7 × 10‐5, and 2.8 × 10‐4. Exposure to microbial contaminants needs to be evaluated on a single meal basis. For chicken, exposure may range from a single drum stick (38g) to a half broiler (176g) but averages around 80g. For beef between 51 and 85g may be consumed during a single meal. Therefore, methods for monitoring must be able to detect at least 1 CFU/80g. Risks for some pathogenic E. coli are estimated at 1,000 to 10,000 less than Salmonella. Therefore, use of coliforms as indicators needs to be assessed and related to occurrence and survival and regrowth potential of the enteric bacteria of greater public health concern. Because, 20% of the U.S. population may be considered to be in a special population category and at an increased risk of severe outcomes, no more than 20% failure of a standard should be acceptable.
RELATIONSHIPS BETWEEN PATHOGEN GROWTH AND THE GENERAL MICROBIOTA ON RAW AND PROCESSED MEAT AND POULTRY
Authors: UPTON MARY
Published: April 2007

Contaminants are capable of growth on meat and poultry products due to the nutrient composition of the products, the available water, the favorable pH and very often the temperature and other conditions of storage. These factors and processing conditions influence greatly the pattern of development of the spoilage and pathogenic microflora. This paper will consider the effects of the general bacterial flora on pathogenic bacteria occurring on meat and poultry as well as the impact of external factors on some of the different types of bacteria found on these products.
ANIMAL HEALTH AND THE ROLE OF THE VETERINARY FOOD HYGIENIST IN THE CONTROL OF MEAT BORNE INFECTIONS
Authors: COLLINS JOHN D.
Published: April 2007

The concept of “Healthy Food from Healthy Animals”relies upon the pre‐and postharvest implementation of an integrated approach for protecting the food product, from contamination or adulteration with harmful agents. This extended form of control is now an integral part of Hazard Analysis Critical Control Point Programs and provides a practical means of validating the health status of herds and flocks of food‐producing animals.

In this context the veterinary food hygienist, as a food company employee, has much to offer the agri‐food industry. She/He can appraise not alone the onfarm conditions but also the animal health and other data provided by the regulatory veterinarian assigned to the plant. Such information, complemented by the plant's own food quality and safety assurance program, can then be used to improve and promote the safety standards of the company. Extended health control programs emphasize the health and safety of the final product for the consumer at each stage of production and processing, and enable veterinary food hygienists, and others, to provide the agri‐food industry, and governmental agencies, with a scientific basis for harmonizing trade in meat and other animal‐derived foods.
USE OF VACCINE AND BIOLOGICAL CONTROL TECHNIQUES TO CONTROL PATHOGENS IN ANIMALS USED FOR FOOD
Authors: ZHAO SHAOHUA , MENG JIANGHONG , ZHAO TONG , DOYLE MICHAEL P.
Published: April 2007

An important component of a Hazard Analysis Critical Control Point (HACCP) approach applied to animal production is reducing the carriage of food‐associated pathogens by animals. Two approaches that have both great potential for reducing pathogen colonization of animals and merit for practical application include (1) vaccination and (2) competitive exclusion. Vaccination involves acquisition of immunity in an animal following exposure to an attenuated pathogen or an antigen of a virulent microorganism. Adherence factors that influence bacterial colonization of animals are useful antigens for vaccines. A strategy to developing a vaccine to reduce carriage of pathogens includes (1) identifying sites of colonization by the pathogen in the animal, (2) defining the mechanism of colonization, (3) characterizing genes that encode colonization factors, (4) transforming the colonization factor antigen genes into a suitable nonpathogenic vector, and (5) determining the optimal methods of immunization. Studies are underway to identify colonization factors of Escherichia coli O157:H7 for use in vaccine development to protect cattle from colonization by this pathogen. Competitive exclusion involves the use of microbial cultures that out‐compete pathogens from colonizing specific niches. A science‐based approach to identifying/developing useful competitive exclusion cultures is to: (1) define how a pathogen colonizes the site of interest, (2) isolate microbes that colonize the same site and produce metabolites that inhibit or kill the pathogen, and (3) verify that the inhibitory microbes, when introduced into pathogen‐free animals, can reduce or prevent colonization by the pathogen. This approach has been used successfully to identify defined bacterial cultures that can greatly reduce colonization of Campylobacter jejuni in poultry. Commercial implementation of techniques of these types is an essential part of the overall HACCP approach to reducing the prevalence of foodborne pathogens from farm to fork.
USE OF TIME/TEMPERATURE INTEGRATORS, PREDICTIVE MICROBIOLOGY, AND RELATED TECHNOLOGIES FOR ASSESSING THE EXTENT AND IMPACT OF TEMPERATURE ABUSE ON MEAT AND POULTRY PRODUCTS
Authors: LABUZA THEODORE P. , FU BIN
Published: April 2007

Temperature abuse is a main concern for chilled and/or MAP meat and poultry products since it will not only cause economic loss, but may also lead to a foodborne illness hazard. A major question for such products is whether organoleptic spoilage due to microbial or chemical action will occur before pathogen numbers or toxin levels become a risk when a product undergoes abuse temperatures. Time‐temperature integrators (TTI) have shown potential to indicate or estimate temperature abuse. However knowledge of predictive food microbiology is needed for each food to employ a TTI tag. The simple Monod and the nonlinear Gompertz function can be used to obtain growth parameters (i.e., lag time, exponential growth rate) from kinetic studies of microbial spoilage. The temperature dependence of these parameters is best evaluated by the Arrhenius or the square root model. Effects of temperature on other deteriorative processes can also be described similarly. Three approaches are presented to evaluate the extent and impact of temperature abuse on meat and poultry by use of TTI tags, which include the effective temperature, the equivalent time and the equivalent point approach. Other technologies to evaluate or to reduce the impact of temperature abuse are also discussed.
TOXICITY EVALUATION OF STRAINS OF CELLULOMONAS
Authors: DEY B.P. , FIELDS M.L.
Published: April 2007

Five strains of Cellulomonas (ATCC 482, ATCC 488, ATCC 491, ATCC 15724 and ATCC 21399) were evaluated for toxicity. Extracts of cells in both water and oil as well as the cell free spent broth injected into fertile chicken eggs were not lethal to the embryos. Viable organisms inoculated in rats, mice and rabbits by oral, subcutaneous and intraperitoneal routes respectively, did not cause generalized or localized infection nor abnormal changes in the vital organs. The sexual maturity, fertility and the vital organs of adult rats as well as the vital data of their progeny were not affected by feeding 10% protein from all strains.
INFLUENCE OF THE INTRINSIC PROPERTIES OF FOOD ON THERMAL INACTTVATION OF SPORES OF NONPROTEOLYTIC CLOSTRIDIUM BOTULINUM: DEVELOPMENT OF A PREDICTIVE MODEL1
Authors: JUNEJA VIJAY K. , MARMER BENNE S. , PHILLIPS JOHN G. , MILLER ARTHUR J.
Published: April 2007

The effects and interactions of heating temperature (70–90C), pH (5–6.5), sodium chloride (0–3%), and sodium pyrophosphate (0–0.3%) on the heat resistance of a six strain mixture of spores of nonproteolytic Clostridium botulinum type B and type E in turkey were examined. Thermal death times were determined in submerged vials heated using a water bath. Heated spores were recovered on Reinforced Clostridial Medium (RCM) supplemented with lysozyme (10 μg/ml). Decimal reduction times (D‐values) were calculated by fitting a survival model to the data with a curve fitting program. The D‐values were analyzed by second order response surface regression for temperature, pH, salt (sodium chloride) and sodium pyrophosphate levels. The four variables interacted to effect the inactivation of spores. Confidence intervals (95%) predicted heat resistance of spores in turkey. The data suggest that the effect of reduced pH in increasing the inactivation was more pronounced at high temperatures and may provide an adequate degree of protection from nonproteolytic C. botulinum spores in minimally processed foods, particularly if employed in conjunction with combinations of salt and sodium pyrophosphate.
THE EFFECT OF LYSOZYME AND BUTYLATED HYDROXYANIZOLE ON SPOILAGE AND PATHOGENIC BACTERIA ASSOCIATED WITH FOODS
Authors: RAZAVI‐ROHANI S. MEHDI , GRIFFITHS MANSEL W.
Published: April 2007

The effect of pH (5 to 7), NaCl concentration (0.5 to 5%) and chelating agents on the antibacterial activity of lysozyme and butylated hydroxyanizole (BHA) was investigated by the Spiral Gradient End Point test. Of all the bacteria tested (including 7 Gram‐positive and 8 Gram‐negative organisms), lysozyme was active only against Lactococcus lactis NCK 400. When EDTA was added, lysozyme was inhibitory for all of the Gram‐positive and 4 of the Gram‐negative species. Butylated hydroxyanizole was active against all the organisms tested, except for 2 pseudomonads, but these were inhibited when EDTA was added. The inhibition effected by lysozyme and BHA, both in the presence and absence of EDTA, was greatest at low pH and high NaCl concentrations. The inhibition by lysozyme was unaffected by other chelators (sodium citrate and monoglycerol citrate). However, sodium citrate promoted the inhibitory effect of BHA towards Gram‐negative bacteria and monoglycerol citrate lowered the minimum inhibitory concentration required by BHA to inhibit 5 of the 7 Gram‐positive bacteria by 10%.
INCIDENCE, SURVIVAL AND GROWTH OF LISTERIA MONOCYTOGENES IN READY‐TO‐USE MIXED VEGETABLE SALADS IN SPAIN
Authors: GARCÍA‐GIMENO ROSA M , ZURERA‐COSANO GONZALO , AMARO‐LÓPEZ MANUEL
Published: April 2007

A total of 116 commercial samples of mixed vegetable salads, packaged in plastic bags, were examined for the presence of Listeria monocytogenes during storage at 4C. Commercial products, belonging to 4 different batches, were sampled over a period of one year and stored for 300 h at 4C in the laboratory. Different sets of enrichment and plating media were used to recover organisms, with subsequent identification by Pasco System and serotyping techniques. Out of a total of 70 control (noninoculated) samples, 21 (30%) were observed to contain Listeria monocytogenes, belonging to serotypes 3a and 3b. A study of salad inoculated with 103 cfu/g Listeria monocytogenes showed that the initial inoculum increased less than tenfold over the experimental period (300 h). During storage of the product, CO2 reached nearly 30% and O2 was no longer detected at 60 h, due to the respiration of the vegetables. The pH inside the packages remained around 6. The specific growth rate in the salad was calculated using the Dmodel Program, which gave a rate of 0.003h‐1, a lower figure than that reported by other authors. This study found growth patterns different to those previously reported for salads with separate ingredients. Our results agree with previous reports that modified atmosphere does not greatly inhibit Listeria monocytogenes. This reflects a lower specific growth rate in this food compared to media, and illustrates the difficulty of validating, in complex food systems, mathematic models based on culture media.
DETERMINANTS THAT MAY BE INVOLVED IN VIRULENCE AND DISEASE IN Campylobacter jejuni
Authors: SMITH JAMES L.
Published: April 2007

Campylobacter jejuni is the major cause of bacterial gastroenteritis in the United States and developed nations. In addition to gastroenteritis, C. jejuni can cause extraintestinal diseases such as the reactive arthritides and Guillain‐Barré syndrome. Most of the illnesses induced by C. jejuni are not life‐threatening but can be severe and long‐lasting. A number of virulence determinants which are believed to be involved in the induction of gastroenteritis, reactive arthritides and Guillain‐Barré syndrome have been demonstrated in C. jejuni. These determinants include attachment and invasion molecules, outer membrane proteins, heat shock proteins, flagella, iron acquiring mechanisms, cytotonic and cytotoxic factors, arthritrogenic antigens that may trigger reactive arthritides and bacterial factors that may induce the Guillain‐Barré syndrome. The published literature concerning the pathogenic mechanisms of C. jejuni indicates that many of the virulence determinants of the organism are inadequately characterized and the role that they play in causing disease is not clear.
INACTIVATION OF SHEWANELLA PUTREFACIENS BY GAMMA IRRADIATION OF RED MEAT AND POULTRY
Authors: THAYER DONALD W. , BOYD GLENN
Published: April 2007

The resistance of Shewanella putrefaciens ATCC 8071, 8072, and 8073 to gamma radiation was determined in the presence and absence of air on mechanically deboned chicken meat (MDCM). The presence or absence of air (oxygen) did not significantly influence resistance to gamma radiation at 5C, and it was very sensitive with a D10 value of 0.11 ± 0.002 kilogray (kGy) on MDCM. A high percentage of cells surviving irradiation were shown by impedance measurements to have suffered injury. The bacteria were significantly more resistant to gamma radiation at temperatures below the freezing point. At a dose of 0.8 kGy lowering the temperature of irradiation by 10 degrees increased the survival of this food spoilage organism by a 1.66 log10. The type of meat (hamburger, ground beef round, ground pork, and ground turkey breast) did not significantly alter resistance of S. putrefaciens to gamma radiation under identical conditions (D10 value = 0.18 ± 0.01 kGy). The minimum radiation dose currently approved for poultry in the USA, 1.5 kGy, should eliminate S. putrefaciens from meats.
DETECTION OF THE VIABLE BUT NONCULTURABLE STATE IN ESCHERICHIA COLI O157:H7
Authors: RIGSBEE WILLIAM , SIMPSON LINDA M. , OLIVER JAMES D.
Published: April 2007

Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is recognized as a frequent cause of gastroenteritis ranging from mild to severe bloody diarrhea. The Shiga‐like toxin produced by EHEC can result in hemolytic uremic syndrome, now the major cause of acute kidney failure in children in the United States. Inadequately cooked beef is most commonly implicated in the transmission of EHEC, although only a small fraction of cattle appear to harbor the organism. In several studies EHEC positive herds were detected only in the summer months correlating with the occurrence of human infections. Numerous E. coli strains have been shown to enter a viable but nonculturable (VBNC) state as a result of environmental stresses, including low temperature. Using traditional plating methods and the BacLight Molecular Probe, we monitored EHEC strains incubated in river water (RW) and artificial sea water (ASW) at temperatures of 5C and 25C for their entry into the VBNC state. EHEC strains remained culturable for over 40 days in both ASW and RW incubated at 25C. In ASW, these levels were higher than a non‐EHEC control. At 5C, the number of culturable EHEC cells dropped gradually in both RW and ASW. Using the BacLight Molecular Probe, we were able to demonstrate that these cells, though not culturable, were viable indicating entry into the VBNC state. Our study suggests that temperature and not salinity is the primary signal for entry into this state.
EFFECT OF HIGH HYDROSTATIC PRESSURE, GAMMA‐IRRADIATION AND COMBINATION TREATMENTS ON THE MICROBIOLOGICAL QUALITY OF LAMB MEAT DURING CHILLED STORAGE
Authors: PAUL PUSHPA , CHAWLA S.P. , THOMAS PAUL , KESAVAN P.C. , FOTEDAR R. , ARYA R.N.
Published: April 2007

The effect of gamma irradiation (1.0 kGy) and high hydrostatic pressure (200 MPa for 30 min), either alone or in combination on the shelf‐life of lamb mince meat at 0–3C was studied. Untreated control samples initially had total microbial counts of 105 CFU/g, 102 CFU/g of coliforms and 104 CFU/g of Staphylococcus spp. Coliforms were eliminated by all the treatments. Staphylococcus spp. however, were reduced only by 1 log cycle when treated with irradiation alone and high pressure alone. These species were a mixture of mannitol‐fermenting and mannitol‐nonfermenting strains. In samples subjected to the combination treatment, Staphylococcus spp. appeared only after 3 weeks of storage and all were mannitol‐nonfermenting. On the basis of microbiological and sensory quality, the shelf‐life of the control sample was less than 1 week. All treated meat samples had a shelf‐life of 3 weeks, but only combination treated samples were free from potentially pathogenic Staphylococcus spp.
EFFECT OF CONCURRENT HIGH HYDROSTATIC PRESSURE, ACIDITY AND HEAT ON THE INJURY AND DESTRUCTION OF LISTERIA MONOCYTOGENES
Authors: STEWART CYNTHIA M. , JEWETT FREDERICK F. , DUNNE C. PATRICK , HOOVER DALLAS G.
Published: April 2007

The effect of concurrent use of high hydrostatic pressure, heat and acidity on Listeria monocytogenes Scott A and CA was investigated. In general, lethality was enhanced when cells were pressurized at higher temperatures or lower pH. Strain CA demonstrated an additional 3‐log10 reduction when pressurized at pH 4.0 as compared with pH 6.0 at 353 MPa, 45C for 10 min. Scott A was reduced an additional 1 log10 by increasing the temperature from 25C to 45C with pressurization at 252 MPa, pH 6.0 for 30 min. Exposure to 404 MPa at 45C for 30 min demonstrated complete injury or death of CA cells with an initial concentration of >108 CFU/mL. At least an 8‐log10 reduction was observed for both L. monocytogenes strains Scott A and CA when exposed to the combined treatments of 252 MPa, 45C, pH 4.0 for 30 min.
INFLUENCE OF OTHER FUNGI ON AFLATOXIN PRODUCTION BY ASPERGILLUS FLAVUS IN MAIZE KERNELS
Authors: AZIZ NAGY H. , SHAHIN AZZA A.M.
Published: April 2007

Experiments were designed to determine whether certain nontoxigenic fungi commonly isolated from maize kernels can affect aflatoxin B1 development when inoculated with A. flavus onto individual unsterilized, and autoclaved maize kernels. Trichoderma viride and Aspergillus niger were found to be strongly antagonist inhibiting the growth of A. flavus by 87 and 66% respectively, whereas Aspergillus versicolor, Fusarium moniliforme, Paecilomyces variotii and Emericella quadrillineata inhibited the growth of A. flavus by less than 51%. Less aflatoxin B1 was detected when A. flavus was paired with A. niger or T. viride than with the other test fungi. When A. niger or T. viride was introduced onto the kernels 72 h before inoculation with A. flavus, no aflatoxin B1 was detected in unsterilized kernels and the levels of aflatoxin B1 were greatly reduced from 700 ppb to 160 and 140 ppb in autoclaved kernels, respectively. When inoculation of A. flavus followed 72 h of incubation of either A. niger and T. viride, no aflatoxin B1 was detected. However, when both A. niger and T. viride were introduced 72 h after inoculation with A. flavus, the levels of aflatoxin B1 were reduced to 385 and 560 ppb, respectively in unsterilized and autoclaved maize kernels. Trichoderma viride and Aspergillus niger may be useful in biological control of aflatoxin contamination of maize kernels.; Accepted for Publication June 11, 1997
THE POTENTIAL FOR CRYPTOSPORIDIUM PARVUM OOCYST SURVIVAL IN BEVERAGES ASSOCIATED WITH CONTAMINATED TAP WATER
Authors: FRIEDMAN D.E. , PATTEN K.A. , ROSE J.B. , BARNEY M.C.
Published: April 2007

Cryptosporidium parvum is an enteric coccidian protozoan which produces an environmentally stable oocyst that is excreted in the feces of infected individuals. There have been ten documented water borne outbreaks in North America. If food or beverages were prepared from contaminated water, that food or beverage would also be a hazard. The objective of this study was to evaluate the survival of Cryptosporidium parvum in beverages. Viability of oocysts, as determined by morphology decreased over 24 h exposure in carbonated beverages. Uptake of vital dyes indicated a loss of >85% of oocyst viability in beer or cola stored at 4C. Loss of viability in tap water, orange juice or infant formula was ± 35%. It is likely that the low pH of the carbonated beverages was involved in the loss of oocyst viability and premature excystation of the sporozoites.
REMOVAL OF LISTERIA SPP. IN A CHEESE FACTORY
Authors: MENENDEZ S. , GODINEZ Ma.R. , RODRIGUEZ‐OTERO J.L. , CENTENO J.A.
Published: April 2007

A total of 311 samples of 10 mL for liquids and 400‐cm2 for surfaces were analyzed in a cheese plant in Galicia (Spain) within a period of 10 months (Feb.‐Nov. 1996). Forty‐six samples were positive for Listeria spp., 36 of which corresponded to L. innocua, 8 to L. monocytogenes and 2 to L. welshimeri. Twenty percent of raw milk samples were Listeria‐positive. Listeria was initially detected on some surfaces of production and ripening rooms, but was never detected after replacing old iron machinery with stainless steel machinery, avoiding the movement of the plant equipment outside the factory building, eliminating wooden boards in the ripening chambers and modifying the disinfection system.; Accepted for Publication May 23, 1997
INHIBITION OF LISTERIA MONOCYTOGENES BY CARNOBACTERIUM PISCICOLA IN VACUUM‐PACKAGED COOKED CHICKEN AT REFRIGERATION TEMPERATURES
Authors: CAMPOS CARMEN A. , MAZZOTTA ALEJANDRO S. , MONTVILLE THOMAS J.
Published: April 2007

Listeria monocytogenes inhibition by bacteriocinogenic Carnobacterium piscicola DX or nonbacteriocinogenic C. piscicola 2818 was examined in vacuum‐packed minimally processed chicken cubes with gravy at 4, 8 and 15C. C. piscicola DX and C. piscicola 2818 at 104 CFU/g were coinoculated individually with a pool of three Listeria monocytogenes strains at 102 CFU/g. At 4 and 8C, C. piscicola DX inhibited growth of L. monocytogenes by 3 logs, significantly (P < 0.05) more than did C. piscicola 2818. At 15C both C. piscicola strains inhibited L. monocytogenes by one log cycle. The pH of all inoculated systems decreased from an initial pH of 6.14 to final values ranging from 6.06 to 5.65 depending on the inocula used. Bacteriocin was detected in the systems coinoculated with C. piscicola DX. These studies demonstrate that lower temperatures and bacteriocin production enhanced L. monocytogenes inhibition by C. piscicola
AN EXPERIMENTAL STUDY IN CONSUMERS' WILLINGNESS‐TO‐PAY FOR AN IRRADIATED MEAT PRODUCT
Authors: GIAMALVA JOHN N. , BAILEY WILLIAM C. , REDFERN MARTIN
Published: April 2007

In a nonhypothetical laboratory experiment, participants were willing to pay an average of $0.71 for the right to exchange a typical meat sandwich for a sandwich irradiated to eliminate the potential risk of foodborne bacteria. Forty‐one of sixty participants (68.3%) were willing to pay some positive amount. Tobit analysis was used in order to allow for the fact that Willingness To Pay (WTP) was censored at zero. WTP was interpreted as the demand for irradiation to control foodborne disease. A positive WTP was interpreted as acceptance of irradiation. The aggregated WTP greatly exceeds the estimated direct costs of foodborne disease, and the estimated costs of irradiation for many food products. There was a positive relationship between WTP and the perceived risk of foodborne disease, and a negative relationship between WTP and years of education.
CONSUMER ATTITUDE AND AWARENESS TOWARDS FOOD‐RELATED HYGIENIC HAZARDS
Authors: SAMMARCO M.L. , RIPABELLI G. , GRASSO G.M.
Published: April 2007

The objective of this study was to investigate awareness and attitude regarding food‐related hygienic practices in the home. For this purpose and within a sanitary education program in pricary schools in a town of Central Italy, a questionnaire was used to collect information from parents of pupils. The questionnaire included questions in four major areas: personal hygiene and cleaning up procedures; meal preparation; food storage; and knowledge of key terms and concepts pertaining to food safety. Analysis of 183 questionnaires showed either risk of cross contamination, improper thawing of food, or inadequate storing and reheating of cooked foods during home food preparation and storage practice. Particularly, 73% of respondents thawed large pieces of frozen food at room temperature; 89% did not reheat cooked food after it had been stored; 75% stored raw meat and poultry in the upper shelves of refrigerators. Precise information on the lack of food safety practices will facilitate the development of proper consumer education programs.
CONTROL OF SALMONELLA IN POULTRY BY RADIOVACCINE
Authors: CRANDER RAMESH , RAJMANE B.V. , THOMAS PAUL
Published: April 2007

A radiovaccine was prepared from Salmonella typhimurium and Salmonella gallinarum cells killed by 5 kGy dose of gamma radiation. This vaccine induced an antibacterial response in chicks. Immunized chicks progressively eliminated the challenged organisms and no salmonellae could be isolated after a period of 35 days. In contrast, chicks from the control group harbored Salmonella The vaccine may find an application in raising “Salmonella free poultry”.
THERMAL RESISTANCE OF YERSINIA ENTEROCOLITICA AND LISTERIA MONOCYTOGENES IN MEAT AND POTATO SUBSTRATES
Authors: DOHERTY ALICE M. , McMAHON CAROL. M.M. , SHERIDAN J.J. , BLAIR I.S. , McDOWELL D.A. , HEGARTY T.
Published: April 2007

The heat resistance of a wild type and nalidixic acid resistant strain of Yersinia enterocolitica, and Listeria monocytogenes, was measured in meat (minced beef and minced beef homogenate) and potato substrates over the temperature range 50–60C. Comparisons of heat resistance were determined using D‐values calculated using a linear survival model. The results showed that the wild‐type strain of Y. enterocolitica was more heat resistant than the mutant (p<0.05). Under most conditions, the use of a nonselective/overlay recovery medium resulted in higher D‐values compared to a selective recovery medium (p<0.05). Analysis of the data using a nonlinear survival model (D1 and D2 ‐values) suggested the presence of heat resistant subpopulations and was particularly evident for the mutant strain, and in potatoes compared to minced beef.
COMPARISON OF SELECTIVE AND NONSELECTIVE ENRICHMENT MEDIA FOR THE ISOLATION OF LISTERIA SPECIES FROM RETAIL FOODS
Authors: WALSH D. , DUFFY G. , SHERIDAN J.J. , BLAIR I.S. , McDOWELL D.A.
Published: April 2007

Enrichment in a nonselective medium, Buffered Peptone Water (BPW) was compared with selective enrichment in University of Vermont Medium (UVMI and UVMII) for the isolation of Listeria spp. from foods. The selectivity of the 2 types of media for the pathogenic strain, Listeria monocytogenes, was also compared. In total, 221 food samples including beef burgers, ham, turkey, lettuce, broccoli, carrots, coleslaw, salads, fish, and ice cream, were purchased from local retail outlets and examined for the presence of Listeria species and L. monocytogenes using both enrichment media Listeria species were detected in 57 (25.8%) samples using UVM, and 56 (25.3%) using BPW. L. monocytogenes was present in 33(14.9%) samples enriched in UVM and in 29(13.1%) samples enriched in BPW. The advantages and disadvantages of selective and nonselective enrichment for detection of Listeria species from a range of foods are discussed.
MICROBIOLOGICAL QUALITY OF COLD MEALS SERVED BY AIRLINES
Authors: HATAKKA MAIJA
Published: April 2007

The microbiological quality of 675 cold meals prepared for serving on aircraft was studied in 1991–1994. The material consisted of appetizers, salads and desserts prepared in 33 countries. The geometric mean of aerobic colony counts, Escherichia coli and Staphylococcus aureus were significantly lower in desserts (p<0.05) than in salads and appetizers. Salmonella was not found in any of the samples. Staphylococcus aureus, Bacillus cereus and Clostridium perfringens were found in 50 samples (7%). In respect of E. coli, S. aureus and B. cereus, the samples exceeded the Routine microbiological standards for aircraft‐ready food; Accepted by the Association of European Airlines by 14%, 7% and 3%, respectively. There were considerable differences in aerobic colony counts, E. coli and B. cereus counts between countries where the food was prepared.
FACTORS AFFECTING THE EMERGENCE OF NEW PATHOGENS AND RESEARCH STRATEGIES LEADING TO THEIR CONTROL1
Authors: MILLER ARTHUR J. , SMITH JAMES L. , BUCHANAN ROBERT L.
Published: April 2007

Control of foodborne emerging or reemerging microbial pathogens has proven to be difficult. Even the Hazard Analysis Critical Control Point (HACCP) approach is intended to manage known hazards. We propose that each change occurring in the food chain – encompassing human, technological, and environmental factors – creates a new selection pressure that drives microbial adaptation and emergence potential. Escherichia coli O157:H7 is examined here, as a case study, to illustrate the multidimensional nature of pathogen emergence. While future emergence or reemergence events are expected, the fundamental questions of what, where, who, when, and how such events will unfold are unknown. Contingency planning can provide responses to probable hazard scenarios, with a goal of developing practical controls. Examples of potential microbial hazards and changes in the food chain are presented. Once a hazard, associated food, locale, and at‐risk population are identified, critical acute research questions need to be answered. Longer term research will improve our ability to respond to the next inevitable emergence event. Such coordinated endeavors will permit rapid modification and deployment of a science‐based hazard management system that will prevent or minimize human risks.
IRISH AND EUROPEAN CONSUMER VIEWS ON FOOD SAFETY
Authors: COWAN CATHAL
Published: April 2007

Results from two consumer surveys are presented. In the first, a EU FAIR (European Union Food, Agriculture and Industrial Research Programme), supported project, three‐thousand consumers (500 in each of six countries, Germany, Italy, Britain, Spain, Sweden and Ireland) were surveyed in March 1997 on their attitudes to the quality and safety of three meats, beef, pork and chicken. This paper deals with the safety aspects of the survey. Many consumers in all six countries said they were eating less beef and more chicken. Overall, the Spanish and Irish appeared to be the most concerned about the safety of meat, the British were somewhat less concerned. While many were confident that the food in shops is safe, there was a sizeable minority who believed the contrary. When looking for information on the safety of meat, butchers, whether independent or in supermarkets, are the group most trusted by consumers. In terms of consumer concerns, about 60 percent of beef consumers were very concerned about hormones, BSE (Bovine Spongiform encephalopathy), antibiotics and bacteria. Pork consumers had similar levels of concern as beef consumers about bacteria, antibiotics and hormones. For chicken there was a higher level of concern about bacteria(Salmonella)(68% were very concerned) and similar levels of concern to pork and beef for the other issues. Generally, fat was the issue of least concern for all three meats. Freshness was considered to be relatively the most helpful of 7 factors used for assessing safety of meat. The country of origin and what the animal was fed were also considered to be relatively helpful. Factors considered to be relatively less helpful were price and the name of the producer. In the second study, over 1200 pre‐leaving certificate Irish school children participated in autumn 1996 in a national survey assessing young people's attitudes to meat. Half of the respondents agreed with the view that eating beef means increasing the risk of getting CJD (Creutzfeldt‐Jakob Disease). Those who agreed were more likely to be less frequent eaters of beef and to have reduced their meat consumption in the post‐BSE period. It was found also that females were more likely to eat less meat than males and to have reduced beef consumption. The implications of some of the findings of these two surveys are discussed.
FACTORS INVOLVED IN RECENT OUTBREAKS OF ESCHERICHIA COLI O157:H7 IN SCOTLAND AND RECOMMENDATIONS FOR ITS CONTROL
Authors: PENNINGTON HUGH
Published: April 2007

This paper describes an outbreak of E. coli O157:H7 that occurred in central Scotland. Edipemiological and microbiological evidence has indicated that the outbreak was comprised of several separate but related incidents, relating to the lunch (attended by around 100 people) held in Wishaw Parish Church Hall, a birthday party held in a public house on November 23, 1996 and retail sales in Lanarkshire and Forth Valley. All isolates of E. coli O157:H7 from individuals in the outbreak belonged to phage type 2 and possessed the verocytotoxin gene VT2. Two hundred sixty‐two of these isolates have been subjected to pulsed‐field gel electrophoresis (PFGE): all had indistinguishable profiles. There were 496 cases in total. There have been 20 deaths (all adults) associated with the outbreak, the highest number of deaths associated with an outbreak of E. coli O157:H7 infection in the world. Of these, 8 people had attended the luncheon served at Wishaw Old Parish Church on November 27, 1996. The age range of those who died was 69 to 93 years. The outbreak was investigated by the Pennington Group who concluded that the circumstances of the central Scotland outbreak, and the inevitable uncertainties that may surround outbreaks generally, provide strong justification for the precautionary, preventative measures proposed and the recommendations made.
MICROBIOLOGICAL HAZARDS DURING PROCESSING OF CROQUETTES
Authors: CÓRDOBA Ma de G. , CÓRDOBA J.J. , JORDANO R.
Published: April 2007

Croquette is a prepared food made with meat or fish as its basic ingredients. Since it is a perishable, heavily handled product, microbiological hazards are associated with the process. Microbiological analyses were performed throughout the commercial processing of chicken croquettes to evaluate the microbial hazards. Moderately high levels of microorganisms were observed in raw materials, but the highest plate counts were noted following extrusion of the croquettes. Pathogenic bacteria, such as Clostridium perfringens, were detected during the process. The increase in the levels of microorganisms observed after extrusion and the presence of C. perfringens were associated with the semi‐solid paste called bechamel. Rapid cooling of the bechamel was critical to avoid microbial proliferation and represented an effective critical control point for the implementation of a HACCP program in the processing of croquettes.
INCIDENCE AND GERMICIDE SENSITIVITY OF SALMONELLA TYPHI AND VIBRIO CHOLERAE O1 IN ALFALFA SPROUTS
Authors: CASTRO‐ROSAS J. , ESCARTÍN E.F.
Published: April 2007

The prevalence of some enteric bacteria in alfalfa sprouts obtained from public markets and supermarkets in Queretaro City was determined. In addition, the antimicrobial effect of several commercial germicides was tested on alfalfa sprouts for reduction of native coliforms and inoculated Vibrio cholerae Ol or Salmonella typhi. Escherichia coli and Salmonella sp. were detected in 74% and 1.1% of 90 of samples, respectively, and no sample tested positive to V. cholerae Ol. Coliforms ranged from 7.3 to 8.5 log10 CFU/g. Treatment of alfalfa sprouts with 200 mg/L of hypochlorite, of a commercial iodophor, or of chlorine dioxide, or with 100 mg/L of Citricidal® for 5 min, reduced native coliforms only by 1–2 log10 CFU/g. Reductions of S. typhi and V. cholerae O1 with 200 mg/L of sodium hypochlorite and 100 mg/L Citricidal® were also no more than J.5 log10 CFU/g. Sprouts from seeds contaminated with V. cholerae O1 that were irrigated daily with water containing 100 mg/L chlorine dioxide, showed significantly lower V. cholerae Ol counts than seeds irrigated with tap water (p<0.05). However, V. cholerae O1 persisted after 8 days of sprouting, when the sprouts are ready for marketing. Treatment of seeds and sprouts with antimicrobials does not appear to be effective for reducing pathogens to safe levels.
INHIBITION OF LISTERIA MONOCYTOGENES AND OTHER BACTERIA IN SPANISH SOFT CHEESE MADE WITH LACTOCOCCUS LACTIS SUBSP. DIACETYLACTIS
Authors: MENDOZA‐YEPES MARIA J. , ABELLAN‐LOPEZ OLGA , CARRION‐ORTEGA JOSE , MARIN‐INIESTA FULGENCIO
Published: April 2007

The inhibitory effects of a lactose‐negative single‐strain starter culture of Lactococcus lactis subsp. diacetylactis were evaluated in Spanish soft cheese (Queso fresco, pH 6.5) against Listeria monocytogenes, Escherichia coli O157:H7, Enterobacter cloacae, Pseudomonas aeruginosa and Pseudomonas fluorescens. Queso Fresco made without starter culture and stored at 3 and 7C supported growth of all bacteria tested, with the exception of E. coli and P. aeruginosa which were unable to grow at 3C. When cheese was made with the starter culture and stored at 7C, L. monocytogenes, P. aeruginosa and E. coli did not grow, the growth of E. cloacae was delayed, and P. fluorescens grew uninhibited. In cheese stored at 3C, only P. fluorescens was able to grow.
PREVALENCE OF SELECTED UNSAFE FOOD‐CONSUMPTION PRACTICES AND THEIR ASSOCIATED FACTORS IN KANSAS1
Authors: ZHANG PING , PENNER KAREN , JOHNSTON JUDY
Published: April 2007

Results of a survey conducted between 1995 and 1996 in Kansas were analyzed to estimate the prevalence of four high‐risk food‐consumption practices and to identify population characteristics associated with each practice. The self‐reported prevalences were 26.5% for home‐canned vegetables, 8.7% for undercooked hamburger, 55.6% for raw or undercooked eggs, and 1.8% for raw milk. Rural residents and those who had a child between ages 13 and 17 were more likely to consume home‐canned vegetables. The consumption of undercooked hamburger was low for respondents with a child from one to four years old but was high for overweight respondents. Those respondents who had higher education and a child between ages 13 and 17 were more likely to consume raw or undercooked eggs. Lower income respondents were more likely to drink unpasteurized milk. The population characteristics identified in this study could be incorporated in the formulation and implementation of educational programs aimed at changing these high‐risk eating behaviors.
EFFECT OF ETHANOL VAPOR ON GROWTH AND TOXIN PRODUCTION BY CLOSTRIDIUM BOTULINUM IN A HIGH MOISTURE BAKERY PRODUCT
Authors: DAIFAS DAPHNE PHILLIPS , SMITH JAMES P. , TARTE ILSEMARIE , BLANCHFIELD BURKE , AUSTIN JOHN W.
Published: April 2007

To determine the effect of ethanol vapor on toxin production by Clostridium botulinum, studies were done in English style crumpets (aw 0.990, pH 6.5) challenged with 500 spores/g C. botulinum types A and proteolytic B and packaged in high gas barrier bags [ethanol transmission rate (ETR) 0.21 g/m2/day @ 25 C]. Crumpets were packaged in air with either commercially available ethanol vapor generators (Ethicap® 2, 4 or 6G) or cotton wool pads saturated with 2, 4 or 6 g of 95% food grade ethanol and stored at 25C. Toxin was detected in all inoculated control crumpets (0% ethanol) after 5 days at ambient temperature (25C). Ethicap® 2G delayed toxicity for 10 days while complete inhibition (>21 days) was observed in all crumpets packaged with 4 or 6G Ethicap® or with 2, 4 or 6 g of ethanol per pad. However, all crumpets were overtly spoiled by this time. Both headspace ethanol and absorption of ethanol by crumpets increased as a function of Ethicap® size/weight of ethanol. Based on these preliminary studies, ethanol vapor would appear to be an effective additional barrier to control the growth and toxin production by C. botulinum in high moisture bakery products and ensure the safety of these products at ambient temperature.
D‐ AND z‐VALUES OF SALMONELLA IN GROUND CHICKEN BREAST MEAT
Authors: MAZZOTTA ALEJANDRO S.
Published: April 2007

The heat resistance of a Salmonella composite of serotypes Typhimurium, Enteritidis, Montevideo, Mbandaka, Heidelberg and Thompson was evaluated in ground chicken breast meat using an end‐point procedure in pouches. A 7D process for Salmonella in chicken was approximately 3 s at 160F (71.1C) with a z‐value of 10.3F (5.7C). The data presented here may help cooked chicken products manufacturers design safe processes that meet the USDA Food Safety and Inspection Service performance standard.
FECAL COLIFORM CONTAMINATION OF BEEF CARCASSES DURING THE SLAUGHTERING PROCESS
Authors: YALÇIN SUZAN , NIZAMLIOǦLU MUSTAFA , GÜRBÜZ ÜMIT
Published: April 2007

The purpose of this study was to determine the fecal coliform counts of beef carcasses during different stages in the slaughter process. A total of nine carcasses were selected at random in the abattoir. The samples were taken by excision from three different sites; rump, brisket and shoulder. The samples were collected from the same carcasses at four different stages of processing; after dressing, after evisceration, after washing and after chilling for 24 h in a chilling room. The processing steps did not increase the fecal coliform counts on the rump samples. There were no significant differences in the samples of rump and shoulder among different processing steps. The contamination level of the brisket after washing was significantly higher than other processing steps. Brisket and shoulder parts are critical points for microbiological sampling as these sites showed higher microbial counts after chilling steps. The data obtained have relevance for the planning of washing methods for the production of clean and safe carcasses.
SAFETY OF IRISH BEEF – CONCERNS, AWARENESS AND KNOWLEDGE OF IRISH CONSUMERS
Authors: RIORDAN NICOLA , COWAN CATHAL , McCARTHY MARY
Published: April 2007

A survey of Irish consumers examined their concerns for the safety of food, their level of knowledge of safe food practices and their awareness of institutional structures to ensure the safety of Irish beef. Sixty‐four percent of the sample expressed concern for the safety of food. Concerns cited include freshness of food, BSE/CJD, antibiotic residue, hygiene standards and bacteria. They perceive many causes of food poisoning and their level of awareness of pathogens varies, depending on the pathogen. The level of knowledge of safe food practice in cooking was good. However, it was lower for food storage practices. Males and those with lower levels of education were less likely to be aware of adequate food safety procedures and need to be the focus of educational programs on safe food handling. As less than half the sample (49%) was aware of institutional structures and 32% of schemes that ensure the safety of Irish beef, it is concluded that it is imperative to more clearly communicate to the public the assurances of any scheme set up. There is also a need to increase awareness level of the bacteria Campylobacter.
PURIFICATION AND MECHANISTIC ACTION OF A BACTERIOCIN PRODUCED BY A BRAZILIAN SAUSAGE ISOLATE, LACTOBACILLUS SAKE 2a
Authors: ROSA C.M. , FRANCO B.D.G.M. , MONTVILLE T.J. , CHIKINDAS M.L.
Published: April 2007

Bacteriocin 2a is produced by a Lactobacillus sake strain isolated from Brazilian sausage. This bacteriocin was purified 72,000 fold by acid extraction from L. sake 2a, followed by cation exchange and reverse phase chromatography. Bacteriocin 2a dissipated the proton motive force in Listeria monocytogenes and reduced the intracellular ATP with no detectable increase in extracellular ATP. Bacteriocin 2a also mediated a concentration‐dependent efflux of carboxyfluorescein from liposomes made from L. monocytogenes lipids. These data indicate that bacteriocin 2a forms pores in the membrane of target cells.
CONSUMER ATTITUDES TOWARD FOOD SAFETY ISSUES
Authors: BREWER M.S. , PRESTAT C.J.
Published: April 2007

The objectives of this study were to survey consumer attitudes about the safety of the food supply in general, relate general concern levels with groups of specific items of concern, regulatory issues and prioritization of food safety funding areas, and to compare these results with results of a similar survey conducted in this lab in 1994. Factor analysis of 360 consumer responses showed six factors underlying the 31 specific items evaluated on individual 5‐point scales (1 = no concern, 5 = very strong concern). MANOVA using general level of food safety concern (independent variable) were significant. Univariate tests showed that as general level of concern with food safety increased, so did concern with chemical issues (artificial colors, pesticide residues, hormones, preservatives, irradiated foods, excessive processing of foods, and plastic packaging), spoilage issues (restaurant sanitation, shelf‐stable foods, pasteurized foods, refrigerated, prepared foods, improper food preparation, microbiological contamination and nutritional imbalances), health issues (vitamin, calorie, carbohydrate, fat, cholesterol and sugar content), regulatory issues (pesticide safety, fish and imported food inspection, and health labeling of food), deceptive practices (naturally occurring toxins, food ingredients associated with allergies and weight reduction diets advertised as healthy) and information issues (availability of detailed information at stores, markets and restaurants).