bluuebunny/crossref_metadata_2025_split huggingface dataset:
N‐NITROSOPROLINE AND N‐NITROSOSARCOSINE IN ESTONIAN FOODSTUFFS
Authors: HAMBURG ANDRES , HAMBURG ANU 
Published: April 2007

ABSTRACT The N‐nitrosoamino acids (NNA) N‐nitrosoproline (NPRO) and N‐nitrososarcosine (NSAR) are precursors of the carcinogenic N‐nitrosamines. Methodology using gas chromatography for their determination and data on their contents in 52 food products are presented. Food products consisted of smoked meats (12), smoked (9) and boiled (11) sausage, cheese (10), fish (7) and beer (3). Results showed that NNA formed during processing, particularly in meat, where levels of NPRO were as high as 353μg/kg. The compounds accumulated in the adipose tissue and surface portion of the product. Smoking caused increased formation of NPRO, while the use of liquid smoke minimized it. NPRO in meat products in natural casings was higher than in synthetic ones, and frying of boiled sausage and hams further enchanced NPRO formation. Like meat, smoked cheese and fish showed consistently higher NNA levels than the non‐smoked products. These data indicate means of reducing NNA contents in foods by modification of processing techniques.
EFFECTIVENESS OF CARNOBACTERIUM PISCICOLA LK5 FOR CONTROLLING THE GROWTH OF LISTERIA MONOCYTOGENES SCOTT A IN REFRIGERATED FOODS1
Authors: BUCHANAN R.L. , KLAWITTER L.A. 
Published: April 2007

ABSTRACT The potential for controlling the growth of Listeria monocytogenes in refrigerated foods using Carnobacterium piscicola LK5, a bacteriocin‐producing strain originally isolated from raw ground beef, was studied using co‐culture techniques. Eight foods, including UHT milk, canned “all‐beef”dog food (cooked meat), raw ground beef, irradiation‐sterilized raw ground beef, chicken roll, pasteurized crabmeat, canned creamed corn, and frankfurters, were inoculated with 103 cfu/g L. monocytogenes Scott A, with and without 104cfu/g LK5, and incubated at 5 and 19C. Samples were removed periodically and assayed for total aerobic plate count using Brain Heart Infusion Agar and L. monocytogenes using Vogel‐Johnson Agar or Modified Vogel Johnson Agar. The growth of L. monocytogenes was suppressed in milk, dog food, crabmeat, creamed corn, and frankfurters stored at 5C. The microorganism was less inhibitory at 19C. In sterile raw ground beef, LK5 inactivated the pathogen at 5C and prevented its growth at 19C. No activity attributable to LK5 was observed in refrigerated nonsterile ground beef or chicken roll; however, these products did not support the psychrotrophic growth of the pathogen even in the absence of LK5. LK5 was most effective in products where the background microflora was reduced by either thermal processing or irradiation treatment. The results indicate that C. piscicola LK5 has potential as a means for preventing the growth of L. monocytogenes in a variety of refrigerated food products.
CONSUMER FOOD SAFETY CONCERNS AND INTEREST IN PESTICIDE‐RELATED INFORMATION
Authors: BRUHN CHRISTINE M. , DIAZ‐KNAUF KATHERINE , FELDMAN NANCY , HARWOOD JAN , HO GENEVIEVE , IVANS ERNESTINE , KUBIN LAUREL , LAMP CATHI , MARSHALL MARY , OSAKI SUSAN , STANFORD GWENDOLYN , STEINBRING YVONNE , VALDEZ ISELA , WILLIAMSON EUNICE , WUNDERLICH EVELYN 
Published: April 2007

ABSTRACTConsumer food safety concerns and interest in pesticide related information was measured by personal interviews with 479 consumers in 14 counties in California. Although concern about pesticide safety was noted by almost half of the respondents, nutritional considerations had the greatest impact on food selection criteria. Of those who volunteered pesticide safety concerns, 15% indicated they sought organic produce and 13% said they avoided or reduced produce purchases. In addition to information about the human health effects of pesticide use, consumers expressed high interest in the environmental effects of pesticide use. Consumers currently use television and newspapers as information sources and prefer these to other sources.
INHIBITION OF LISTERIA MONOCYTOGENES BY LACTOCOCCUS LACTIS SUBSP. LACTIS ISOLATED FROM ITALIAN RAW HAM
Authors: STECCHINI MARA LUCIA , AQUILI VALERIA , SARAIS ILEANA , PITOTTI ANNA 
Published: April 2007

ABSTRACT A total of 168 strains of lactic acid bacteria were isolated from Italian raw ham and screened for antagonistic activity against Listeria monocytogenes by using an agar spot assay. Only one strain of Lactococcus lactis subsp. lactis produced antagonistic effects other than inhibition by low pH and hydrogen peroxide. The proteinaceous nature of the compound produced by L. lactis B10 was demonstrated by its inactivation by proteolytic enzymes. The cell‐free culture super‐natants (filtered and heat‐treated) showed a bactericidal mode of action. Bacteriocin produced by L. lactis B10 was inhibitory to other lactic acid bacteria and one strain of Staphylococcus aureus, but not to the gram‐negative bacteria tested.
CONSUMER WILLINGNESS TO PAY FOR SAFER FOOD PRODUCTS1
Authors: SHIN SEUNG‐YOULL , KLIEBENSTEIN JAMES , HAYES DERMOT J. , SHOGREN JASON F. 
Published: April 2007

ABSTRACT Existing estimates of societal costs of food‐borne pathogens use only out‐of‐pocket expenses, such as hospital charges, and ignore the cost of (or willingness to pay to avoid) the pain and suffering associated with a food‐borne disease. This paper develops and implements a method to determine consumers’willingness to pay for safer food products. The results show that, for each meal that may be contaminated, participants in this study would pay 55 cents to eliminate Salmonella and 81 cents to eliminate Trichinella spiralis.
SEAFOOD ALLERGY: PREVALENCE AND TREATMENT
Authors: LEHRER SAMUEL B. , HELBLING ARTHUR , DAUL CAROLYN B. 
Published: April 2007

ABSTRACTSeafood is a common cause of food allergy. Allergic reactions are reported by consumers following ingestion of seafood meat and by processing workers after occupational exposure to seafood by inhalation of vapors generated during cooking. Although seafood allergy is commonly observed in clinical practice, its precise prevalence is not established. Based on our estimates, approximately 100,000 to 250,000 Americans are at risk of developing allergic reactions to seafood products. In this study, skin testing, in vitro assays and double‐blind, placebo‐controlled food challenge were employed to investigate seafood allergy in shrimp‐allergic individuals. As in most food allergy studies only 1/3 of the alleged shrimp‐sensitive subjects had a positive shrimp challenge test. The combination of a positive shrimp skin test and shrimp RAST (>11% bound) had the best predictive value (87%) for a positive challenge response. Although occupational seafood allergy is not well‐studied, based on a Canadian investigation, it can be estimated that 57,000 American seafood workers are at risk of developing work‐related allergic reactions. Since seafood is a major food allergen in consumers and industrial workers, further studies are necessary. Despite developments of new antiallergic therapies, avoidance continues to be the best “treatment”for allergic ingestive, inhalative and occupational disease.
RESPONSE SURFACE MODELS FOR THE EFFECTS OF TEMPERATURE, pH, SODIUM CHLORIDE, AND SODIUM NITRITE ON THE AEROBIC AND ANAEROBIC GROWTH OF STAPHYLOCOCCUS AUREUS 196E1
Authors: BUCHANAN R.L. , SMITH J.L. , MCCOLGAN C. , MARMER B.S. , GOLDEN M. , DELL B. 
Published: April 2007

ABSTRACT The effects and interactions of temperature (12–45C), initial pH (4.5–9.0), NaCl (0.5–16.5%), and sodium nitrite (1–200 μg/ml) on the aerobic and anaerobic growth of Staphylococcus aureus 196E were studied using 50 ml portions of Brain Heart Infusion Broth in 250ml unsealed and sealed trypsinizing flasks, respectively. The flasks were inoculated to a level of approximately 103 cfu/ml, incubated on a rotary shaker, sampled periodically, and enumerated on Tryptic Soy Agar. Growth curves were generated by fitting the data to the Gompertz function using nonlinear regression analysis. The general growth characteristics of S. aureus in response to the five environmental variables were similar to those observed by other investigators including (1) enhanced growth in the presence of oxygen, (3) ability to grow at high sodium chloride concentrations, and (3) dependence of the bacteriostatic activity of sodium nitrite on pH and oxygen availability. Supplemental studies indicated that growth kinetics were independent of inoculum size, which allowed the Gompertz A term to be treated as a constant. However, the maximum population density (MPD) achieved by the cultures was dependent on the independent variables, requiring that it be modeled in addition to the Gompertz B and M terms. The MPD was then used to calculate the Gompertz C term. Quadratic and cubic response surface models were generated using various data transformations. Quadratic models using and LN‐transformation provided reasonable predictions of the effects of the four variables on the growth kinetics of S. aureus, and should prove useful for providing initial estimates of the behavior of S. aureus in foods.
GROWTH OF LISTERIA MONOCYTOGENES, AEROMONAS HYDROPHILA AND YERSINIA ENTEROCOLITICA ON COOKED MUSSEL TISSUE UNDER REFRIGERATION AND MILD TEMPERATURE ABUSE
Authors: HUDSON J. ANDREW , AVERY SHERYL M. 
Published: April 2007

ABSTRACTStrains of the psychrotrophic bacteria Listeria monocytogenes, Aeromonas hydrophila and Yersinia enterocolitica were inoculated onto samples of cooked mussel tissue and incubated at 5 and 10C under both aerobic and anaerobic conditions. These organisms were enumerated over a time course and data were analyzed to give values for the lag and generation times. All species grew under all conditions, and the rate of growth was similar under aerobic and anaerobic incubation. Predicted growth kinetic values from response surface models and measured growth rates for L. monocytogenes and A. hydrophila were in reasonable agreement, but similar comparisons for Y. enterocolitica gave shorter predicted lag and generation times than were measured. A combination of models from different sources would have given more accurate predictions than any one individual model.
INHIBITION OF STAPHYLOCOCCUS AUREUS IN BUFFER, CULTURE MEDIA AND FOODS BY LACIDIN A, A BACTERIOCIN PRODUCED BY LACTOBACILLUS ACIDOPHILUS OSU133
Authors: LIAO CHII‐CHERNG , YOUSEF AHMED E. , CHISM GRADY W. , RICHTER EDWARD R. 
Published: April 2007

ABSTRACTThirty seven strains of lactobacilli and leuconostocs were screened for bacteriocin production. A bacteriocin‐like substance (designated lacidin A) was detected in culture filtrate of Lactobacillus acidophilus OSU133. Lacidin A inhibited Enterococcus faecalis, L. acidophilus, Lactobacillus delbrueckii subsp. lactis, and Staphylococcus aureus. The bacteriocinogenic nature of lacidin A was confirmed by eliminating the inhibitory effects of acid, hydrogen peroxide and phage and by loss of activity upon hydrolysis with proteolytic enzymes. The bacteriocin is relatively heat‐stable and has considerable bactericidal action against S. aureus in phosphate buffer. Lacidin A also demonstrated bacteriostatic action against S. aureus in brain heart infusion and heat‐treated milk and liquid whole egg.
MATHEMATICAL MODELING OF MICROBIAL GROWTH: A REVIEW
Authors: SKINNER GUY E. , LARKIN JOHN W. , RHODEHAMEL E. JEFFERY 
Published: April 2007

ABSTRACTThe use of mathematical modeling of microbiological behavior to predict and evaluate food safety or shelf life is receiving considerable interest. Researchers are attempting to use mathematical equations that incorporate such critical growth factors as pH, aw, and NaCl content to predict microbial growth and/or toxin production in order to replace traditional time‐intensive challenge studies. Predictive equations can be divided into probabilistic, regression, Arrhenius, and square root models. Models vary greatly in theory and complexity. Predictive models are used to monitor processes ranging from temperature during distribution to inventory control. They have been shown to be useful in product development and shelf‐life estimation when safety is not an issue. Most models are generated by regression analysis of data obtained from laboratory experiments. Statistically based models, even when conservatively derived, are not appropriate as the only criterion for evaluating food safety.
ENRICHMENT OF SEVERELY AND MODERATELY HEAT‐INJURED LISTERIA MONOCYTOGENES CELLS
Authors: WANG SHU‐YING , HITCHINS ANTHONY D. 
Published: April 2007

ABSTRACTRecovery of injured cells of a 90% heat kill of Listeria monocytogenes strain Lm82 in Trypticase soy yeast extract broth (TSBYE) at 30C was determined in enrichment broth and modified enrichment broth. Although the surviving population was heterogeneous with respect to degree of damage, two fractions of surviving cells defined as moderately and severely damaged were considered. Progeny of moderately damaged survivors (NaCl‐sensitive but not enrichment medium‐sensitive) increased about 100‐fold in 5 h; severely damaged cells (enrichment medium‐ and NaCl‐sensitive) did not grow in this time period. Most of the severely damaged cells required 20 h or longer to recover in TSBYE and even longer in TSBYE plus selective agents. Recovery was accelerated either by adding sodium pyruvate or by reducing the oxygen level. The results were used to design a Mark I preenrichment/enrichment protocol based on the U.S. Food and Drug Administration's selective enrichment broth.
SHELF‐LIFE EXTENSION BY PHENYLGLYOXAL OF CLOSTRIDIUM SPOROGENES‐INOCULATED VACUUM‐PACKAGED GROUND BEEF
Authors: BOWLES BOBBY L. , MILLER ARTHUR J. 
Published: April 2007

ABSTRACTPhenylglyoxal (PG), an aromatic α‐dicarbonyl, is used in a variety of industrial, medical, and biological research applications. The compound delays spore germination and inhibits vegetative cells of both aerobic and anaerobic sporeforming bacteria, interacts with several critical bacterial growth factors, and is structurally similar to a number of approved food flavoring agents. Previous research demonstrated inhibitory activity against Clostridium sporogenes in model systems. Therefore, we investigated the shelf‐life enhancing effectiveness of PG in C. sporogenes‐inoculated vacuum‐packaged ground beef at 32C. During extended incubation under temperature abuse conditions, PG delayed undesirable color changes and prevented organoleptic spoilage. Five μg PG/g inhibited proteolysis, while 156 μg PG/g delayed conversion of myoglobin to metmyoglobin, prevented H2S production, maintained product quality and texture for 25 days, and reduced thermal resistance of C. sporogenes spores at 90C. The observed activity of PG suggests that similar activity might be found with currently approved α‐dicarbonyls. Furthermore, the compound's effect on thermal resistance may serve as an example of compounds that could be used to reduce thermal processing requirements of heat‐sensitive and/or minimally processed foods.
INFLUENCE OF LACTIC ACID AND MODIFIED ATMOSPHERE ON THERMAL DESTRUCTION OF LISTERIA MONOCYTOGENES IN CRAWFISH TAIL MEAT HOMOGENATE1
Authors: DORSA WARREN J. , MARSHALL DOUGLAS L. 
Published: April 2007

ABSTRACT Precooked homogenized crawfish tail meat was inoculated with Listeria monocytogenes, treated with lactic acid, and packaged in various atmospheres for D value determinations at 60C. D60 values using 0.0, 0.5, 0.75, and 1.0% lactic acid (LA) treated meat were 4.68, 4.41, 3.46, and 2.49 min, respectively. LA increased sensitivity of L. monocytogenes to heat but this was not solely due to a reduction of pH. Sensory analyses of odor, color, taste, and texture of uninoculated whole crawfish tail meat demonstrated no significant differences (P > 0.05) between LA treated samples and controls. D60 values for the bacterium in crawfish tail meat homogenate packed in air, O2, CO2, or N2 were 10.58, 9.22, 11.68, or 12.97 min, respectively, which were not significantly different (P > 0.05). When 1% LA was added, significant decreases (P < 0.05) in D60 values were observed in each packaging atmosphere. Similar (P > 0.05) D60 values for crawfish tail meat treated with 1% LA and packed in air, O2, CO2, or N2 were 3.44, 3.88, 3.48, or 3.08, respectively. These results show that heat treatments of 60C were lethal to L. monocytogenes in packaged crawfish tail meat homogenate regardless of package atmosphere. Additionally, LA increased the lethality of heat to the bacterium in all tested package atmospheres.
EFFECT OF POLYPHOSPHATES AND NaCl ON AEROMONAS HYDROPHILA K144
Authors: PALUMBO SAMUEL A. , CALL JEFFREY E. , COOKE PETER H. , WILLIAMS AARON C. 
Published: April 2007

ABSTRACT Polyphosphates are multifunctional ingredients added to many foods, particularly meat products. In addition to their moisture‐binding properties, polyphosphates have been reported to inhibit various bacteria. In the current study, four food‐grade polyphosphates were evaluated for their effects on the growth of Aeromonas hydrophila K144 in both a model system and a food system. Since polyphosphates can interact with other food factors, effect of these compounds were studied at different NaCl levels and temperatures. The model system was BHI Broth modified by the addition of polyphosphates (sodium pyrophosphate, sodium tripolyphosphate, Hexaphos, or Sodaphos) and NaCl; incubation was aerobic at 5 or 28C. The food system was ground pork with NaCl and polyphosphate added and inoculated with A. hydrophila. Individually, the polyphosphates were relatively noninhibitory in both BHI broth and ground pork, but NaCl and temperature interacted with the polyphosphates in the model system to increase generation and lag times of A. hydrophila. In BHI broth, a combination of 2% of any of the polyphosphates tested and 3.5% NaCl inactivated the bacterium; this inactivation was temperature‐dependent. By both a plating system and electron microscopy, the polyphosphate‐NaCl combination was shown to injure the bacterium. In the ground pork, the polyphosphate‐NaCl combination limited growth of the bacterium during refrigerated storage. These results suggest that polyphosphates could be useful to control the presence of A. hydrophila in certain foods.
CHARACTERIZATION OF AEROMONAS SPECIES ISOLATED FROM FOOD
Authors: RASHAD FERIAL M. , ABDEL‐KAREEM HUSSEIN 
Published: April 2007

ABSTRACT Characterization of ten Aeromonas spp. isolates from local foods and A. hydrophila ATCC 7965, revealed that all strains of A. hydrophila, A. sobria and one strain of A. caviae showed strong hemolytic activity. All of them were protease producers except one A. caviae strain. Some A. hydrophila and A. caviae strains fermented lactose, coagulated milk and reduced litmus. The majority of strains were resistant to at least 5 of 14 antibiotics tested. All the strains grew over the range of 5–42C except those of A. caviae which failed to grow at 42C. Frozen storage at ‐16C greatly decreased the viability of the tested strains. Radiation D10values of strains ranged from 0.109–0.253 kGy in nutrient broth and increased when some strains were irradiated in ground meat at room temperature. Both strains of A. hydrophila (ATCC andFI), A. sobria FI and A. caviae FI grew normally in the presence of 1 and 3% salt. Only A. hydrophila FI tolerated 6.5% salt. These four strains were able to grow in the presence of 0.05–0.3% potassium sorbate at pH 7.0, while at pH 5.0 the presence of sorbate prevented their growth.
INFLUENCE OF MOISTURE CONTENT AND STORAGE TEMPERATURE ON THE PRODUCTION OF AFLATOXIN BY ASPERGILLUS FLAVUS EA‐81 IN MAIZE AFTER EXPOSURE TO GAMMA RADIATION
Authors: HASSAN ATEF AHMED , AZIZ NAGY HALIM 
Published: April 2007

ABSTRACT The effect of gamma radiation on aflatoxin production by Aspergillus flavus EA‐81 in maize with different initial moisture levels was determined over a 15‐day period. The viability of A. flavus on maize decreased over time with increasing moisture contents and storage at 8C. After 45 days at 28C, levels of viable conidiospores of A. flavus increased from 4.5 × 107 to about 3.0 × 108 per gram of maize. Levels of aflatoxin B1 produced by A. flavus were 10 μg kg‐1 in the maize stored at 8C after 45 days. Production of aflatoxin was highest at 40% moisture and 28C. Irradiation of 1.0 or 2.0 kGy greatly reduced the level of mold growth relative to unirradiated controls. A dose of 4.0 kGy eliminated all viable fungi. Aflatoxin B1 production decreased with increased levels of irradiation and was negligible at 4.0 kGy. When maize was inoculated after irradiation and stored, the spore counts and aflatoxin levels were higher than in unirradiated and inoculated controls after 30 days. Apparently, the natural competitive microflora prevented growth and thus limited higher concentrations of aflatoxin in maize.
HEAT RESISTANCE IN DIFFERENT HEATING MEDIA OF LISTERIA MONOCYTOGENES ATCC 15313 GROWN AT DIFFERENT TEMPERATURES
Authors: PAGÁN R. , MAÑAS P. , ALVAREZ I. , SALA F.J. 
Published: April 2007

ABSTRACT This paper examines the influence of growth temperature on thermal resistance of Listeria monocytogenes ATCC 15313. Regardless of the incubation temperature, the heat resistance of Listeria monocytogenes increased during incubation until the stationary phase of growth was reached. The maximum heat resistance of cells grown at 4C, 20C or 37C was attained after 14 days, 36 h and 18 h of incubation, respectively. After longer incubation times the heat resistance of cells grown at 4C and 20C did not change but that of cells grown at 37C decreased. The maximum heat resistance was usually greater at higher incubation temperatures. However, the magnitude of these differences depended on the pH and composition of heating media. By raising the incubation temperature from 4C to 37C, the D62 value in pH 7 citrate‐phosphate buffer increased from 0.13 to 0.34 min. However, when skimmed milk was used as menstruum this difference was not observed. Cells grown at 37C attained maximum heat resistance at pH 7 but those grown at 4C, at pH 6. The magnitude of the effect of the incubation temperature on heat resistance was constant at all heating temperatures tested (z = 6 ± 0.8C). The higher heat resistance of cells grown at higher temperatures was not due to a greater capacity of heat damage repair
SOURCES OF CONTAMINATION DURING SLAUGHTER AND MEASURES FOR CONTROL
Authors: SHERIDAN J.J. 
Published: April 2007

ABSTRACT This paper is concerned with processes and procedures involved in the contamination of beef, lamb and pork carcasses during slaughter. The hides of beef and the fleece of sheep are major sources of carcass contamination. The spread of pathogens from beef hides to the carcass, operatives and surfaces in the abattoir is demonstrated. Efforts to clean the hide of cattle and the fleece of sheep are outlined, with reference to the success of these treatments in reducing carcass contamination. The effect of bringing very dirty or dungy animals to slaughter is considered in terms of the effect on carcass contamination after slaughter. The influence of tying the bung (or rectum) in reducing carcass contamination is discussed, as is the use of plastic bags as an additional control in preventing pathogen spread on pig carcasses. The relationship of this revised procedure in reducing the occurrence of yersiniosis in Norway is shown. The use of a commercially automated system to tie beef bungs is discussed in relation to reducing carcass contamination. A comparison between the removal of faecal contamination on carcasses by trimming or using a new steam‐vacuumized system is presented. The effect of preevisceration washing of beef carcasses is described and the rationale relating to bacterial removal using this treatment is discussed. The influence of evisceration as a source of carcass contamination is demonstrated in relation to sheep slaughter. The processes of carcass decontamination using washing with water at different temperatures, steam pasteurization and hot lactic acid are compared in relation to their ability to remove bacteria from beef carcass surfaces. Finally, the effect of line speed and the impact of technology advances on beef and sheep carcass contamination is reviewed.