Characterization and Behavior of Salmonella javiana During Manufacture of Mozzarella-type Cheese1

1990 ◽  
Vol 53 (6) ◽  
pp. 461-464 ◽  
Author(s):  
K. F. ECKNER ◽  
R. F. ROBERTS ◽  
A. A. STRANTZ ◽  
E. A. ZOTTOLA
Keyword(s):  
Manufacturing Process ◽  
Titratable Acidity ◽  
Penicillin G ◽  
Direct Plating ◽  
Log Reduction ◽  
Patient Isolate ◽  
Metabolic Activities ◽  
And Behavior

A patient isolate of Salmonella javiana implicated in an outbreak of salmonellosis in Minnesota was characterized and used to examine its response to Mozzarella manufacturing conditions. The strain possessed biochemical-metabolic activities typical of Salmonella species. Growth was observed in 6.5% NaCl Trypticase Soy Broth (TSB) but not in 12% NaCl TSB. This S. javiana strain was resistant to two antibiotics, penicillin G and erythromycin. Pasteurization trials indicated the strain did not survive pasteurization and that pasteurization affected a log reduction of greater than 9 cycles. Mozzarella-type cheese was manufactured from milk inoculated with S. javiana at levels of 1 × 104 and 1 × 106 per ml milk. Manufacturing process was monitored by following pH, titratable acidity, and temperature. Survival of S. javiana was monitored using traditional enrichment procedures and direct plating procedures. S. javiana survived and grew through the acid-ripening phase, but temperatures attained in cheese mass during stretching and molding (60°C, 140°F) killed all Salmonella present. No subsequent process steps were found positive for Salmonella.

scholarly journals Validation of a Traditional Italian-Style Salami Manufacturing Process for Control of Salmonella and Listeria monocytogenes†

2006 ◽  
Vol 69 (4) ◽  
pp. 794-800 ◽  
Author(s):  
K. K. NIGHTINGALE ◽  
H. THIPPAREDDI ◽  
R. K. PHEBUS ◽  
J. L. MARSDEN ◽  
A. L. NUTSCH
Keyword(s):  
Listeria Monocytogenes ◽  
Manufacturing Process ◽  
Raw Material ◽  
Cell Recovery ◽  
Recovery Method ◽  
Direct Plating ◽  
Selective Media ◽  
Injured Cell ◽  
Pathogen Populations ◽  
Proximate Analyses

Italian-style salami batter (formulated with pork shoulder) was inoculated with ca. 7.0 log CFU/g of either Salmonella or Listeria monocytogenes. Salami links (55-mm cellulose casings) were fermented at 30°C for 24, 40, or 72 h and then dried to target moisture/protein ratios (MPRs) of 1.9:1 or 1.4:1. Links were sampled after fermentation (24, 40, and 72 h) and after combined fermentation-drying treatments (MPRs of 1.9:1 and 1.4:1 for all fermentation periods), and microbiological and proximate analyses were performed at each sampling. Pathogen populations were enumerated by direct plating on selective agar and by an injured-cell recovery method. When enumerated by the injured-cell recovery method, Salmonella populations were reduced by 1.2 to 2.1 log CFU/g after fermentation alone (24 to 72 h) and by 2.4 to 3.4 log CFU/g when fermentation was followed by drying. Drying to an MPR of 1.4:1 was no more effective than drying to an MPR of 1.9:1 (P > 0.05). When enumerated directly on selective media, Salmonella populations were reduced from 1.6 to 2.4 log CFU/g and from 3.6 to 4.5 log CFU/g for fermentation alone and fermentation followed by drying, respectively. L. monocytogenes populations were reduced by <1.0 log CFU/g following all fermentation and combined fermentation-drying treatments, regardless of the enumeration method. These results suggest that the Italian-style salami manufacturing process evaluated does not adequately reduce high pathogen loads. Processors may thus need to consider supplemental measures, such as raw material specifications and a final heating step, to enhance the lethality of the overall manufacturing process.

scholarly journals Biochemical, Oxidative, and Lipolytic Changes during Vacuum-Packed Storage of Dry-Cured Loin: Effect of Chestnuts Intake by Celta Pigs

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
María Gómez ◽  
Aida Cachaldora ◽  
Sonia Fonseca ◽  
Rubén Domínguez ◽  
Javier Carballo ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Manufacturing Process ◽  
Meat Product ◽  
Titratable Acidity ◽  
Canonical Analysis ◽  
Lipid Fractions ◽  
Cured Meat ◽  
Oxidation Parameters

The effect of the inclusion of chestnuts in the finishing diet of Celta pig breed on the characteristics of dry-cured loin, a traditional Spanish dry-cured meat product, after the manufacturing process and the vacuum-packed storage was studied. In general, no significant differences between the diets (chestnut, mixed, and concentrate diet) were obtained for physicochemical (moisture, intramuscular fat, and titratable acidity) and lipolytic parameters. Lower pH and higher values for oxidation parameters (peroxide and TBA values) were obtained in loins from pigs fed with chestnuts. However, no differences were found for fatty acids from the different lipid fractions when diets were compared, with the exception of some minor fatty acids. Free fatty acids represented over 2.7% of the fat in the final product. The distinction between diets was procured when a discriminant canonical analysis was performed for fatty acid contents. After vacuum-packed storage, only a slight evolution of the studied parameters was obtained.

scholarly journals Effect of production process and high-pressure processing on viability of Salmonella spp. in traditional Italian dry-cured coppa

2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Roberta Taddei ◽  
Federica Giacometti ◽  
Lia Bardasi ◽  
Paolo Bonilauri ◽  
Mattia Ramini ◽  
...  
Keyword(s):  
Production Process ◽  
Manufacturing Process ◽  
Treatment Temperature ◽  
High Pressure Processing ◽  
Combined Processes ◽  
Combined Approach ◽  
Salmonella Spp ◽  
Raw Meat ◽  
Log Reduction ◽  
Additional Reduction

The aim of the study was to investigate the combined effect of the manufacturing process followed by HPP treatment on the inactivation of Salmonella spp. in artificially contaminated coppa samples, in order to verify the ability of the combined processes to achieve the objective of a 5-log reduction of Salmonella spp. needed for exportation to the U.S. Fresh anatomical cuts intended for coppa production were supplied by four different delicatessen factories located in Northern Italy. Raw meat underwent experimental contamination with Salmonella spp. using a mixture of 3 strains. Surface contamination of the fresh anatomical cuts was carried out by immersion into inoculum containing Salmonella spp. The conditions of the HPP treatment were: pressure 593 MPa, time 290 seconds, water treatment temperature 14°C. Surface and deep samples were performed post contamination (T0), end of the cold phase (T1), end of process (Tend), and after HPP treatment (postHPP) and Salmonella spp. Enumerated. The results of this study show a significant reduction of Salmonella spp. all through the production process (P<0.01) for all companies, followed by an additional reduction of bacterial counts due to HPP treatment (P<0.01), both in superficial and deep contaminations (P<0.01). The superficial overall reduction resulted of 1.58 to 5.04 log CFU/g during the production process. HPP treatment resulted in a significant (P<0.01) superficial and deep decrease in Salmonella spp. enumeration varying from 0.61 to 4.01 log and from 1.49 to 4.13 log. According to the data presented in this study, only the combined approach of coppa manufacturing process followed by HPP treatment always led to a 5-log reduction of Salmonella spp. required by USDA/FSIS guidelines.

scholarly journals Antimicrobial susceptibility and immunomodulatory properties of lamb isolate of lactobacillus mucosae, new probiotic candidate

2013 ◽  
Vol 60 (2) ◽  
pp. 1-6
Author(s):  
Andrea Bilková ◽  
Martina Dubničková ◽  
Hana Kiňová Sepová
Keyword(s):  
Mononuclear Cells ◽  
Relative Activity ◽  
Penicillin G ◽  
Stomach Mucosa ◽  
Human Mononuclear Cells ◽  
Bactericidal Activities ◽  
Metabolic Activities ◽  
Lactobacillus Mucosae ◽  
And Staphylococcus Aureus

Abstract In the process of selecting a new probiotic candidate, several bacteria were isolated from the stomach mucosa of a lamb. Among them, three lactobacilli strains were identified and partially characterised. The strain, Lactobacillus mucosae D, showed several characteristics appropriate to the probiotics. In this study, we have focused on the further characterisation of L. mucosae D and testing of its ability to modulate metabolic and immunomodulatory activities of human mononuclear cells in vitro. L. mucosae D is resistant to antibiotics, like penicillin G, oxacillin, vancomycin and chemotherapeutics ofloxacin and ciprofloxacin. In in vitro conditions, L. mucosae D caused a significant increase in phagocytic activity and index (relative activities 1.05 and 1.44, respectively) of human monocytes. It decreased bactericidal activities of monocytes against Escherichia coli (relative activity 0.73) and Staphylococcus aureus (relative activity 0.36), whereas, candidacidal activity was enhanced (relative activity 1.15). Metabolic activities, lysozyme and peroxidase activity, of mononuclear cells were not changed or increased, respectively. L. mucosae D displayed the ability to enhance production of pro-inflammatory cytokine, IL-1β, in monocytes in vitro (relative activity 2.60). Therefore, we state that lamb isolate, L. mucosae D, has the required attributes for being a potential probiotic candidate.

scholarly journals Evaluation of quality measurement of Olomouc cake of cheese (Olomoucké tvarůžky) during ripening

2012 ◽  
Vol 60 (5) ◽  
pp. 205-210 ◽  
Author(s):  
Daniela Strnadová ◽  
Hana Konečná ◽  
Miroslav Jůzl
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Manufacturing Process ◽  
Dry Matter ◽  
Quality Measurement ◽  
Titratable Acidity ◽  
Summer Period ◽  
Brevibacterium Linens ◽  
Spring Period

Olomouc cake of cheese (Olomoucké tvarůžky) is smear-ripened cheese, which is produced from sour industrial curd. Brevibacterium linens, which are added during the production process, are reproducing and make gold-yellow smear cover. The aim of this work was to assess the chemical analysis of the quality of Olomouc cake of cheese. Changes in chemical composition were evaluated during different stages of production and at the same time it was detected whether changes in chemical composition during the manufacturing process are same in spring as well as in summer, without statistically significant differences. Dry matter of Olomouc cake of cheese was ranged from 35 % to 39 %. The increase of dry matter during production is evident, but these changes were in the most cases not statistically signifiant (P > 0.05). The value of titratable acidity of the cheese considerably changes during the manufacturing process, it has a decreasing tendency. Titratable acidity of cheese after shaping was 106.64 (136.12) SH and at the end of life it was 49.91 (65.06) SH. These changes were very highly statistically significant (P < 0.001). Increasing the dry matter of cheese is also proportionatelly increase content of salt in cheese, although this changes are not statistically significant (P > 0.05) in cheese from summer period. Content of salt is increased from 5.30 % to 5.98 %, respectively 6.10 %. In spring period the oposite changes in most cases occured (P < 0.001), it is increased from 4.27 % to 6.20 %, respectively 6.94 %. When the chemical composition of the cheese in spring and in summer period is compared, there are no significant changes (P > 0.05).

scholarly journals Survival of Enterohemorrhagic Escherichia coli O157:H7 During the Manufacture and Curing of Cheddar Cheese†

1996 ◽  
Vol 59 (5) ◽  
pp. 460-464 ◽  
Author(s):  
CHRISTINE J. REITSMA ◽  
DAVID R. HENNING
Keyword(s):  
Escherichia Coli ◽  
Manufacturing Process ◽  
Cheddar Cheese ◽  
Enterohemorrhagic Escherichia Coli ◽  
Escherichia Coli O157 ◽  
Direct Plating ◽  
E Coli ◽  
Test Kit ◽  
Unit Reduction

The ability of enterohemorrhagic Escherichia coli O157:H7 to survive a standard Cheddar cheese manufacturing process and subsequent curing was determined. Two treatments with added E. coli O157:H7 were designed with target levels 1 × 103 CFU/ml and 1 CFU/ml of cheese milk. Cheese samples were analyzed for E. coli O157:H7 during manufacture at 14, 28, 42, 60, and 74 days, and at 28-day intervals thereafter until the organism could no longer be detected using direct plating or enrichment in two successive samples. Typical colonies on 3M Petrifilm® E. coli Count Plates were counted as presumptive E. coli O157:H7 and were confirmed with the 3M Petrifilm® Test Kit—HEC for hemorrhagic E. coli O157:H7. When no E. coli O157:H7 were detected in the cheese with the Petrifilm®plates, a 25-g sample of cheese was enriched in modified EC broth with novobiocin to detect viable E. coli O157:H7. Cheese made with 103 CFU/ml of milk showed a 2-log-unit reduction after 60 days of ripening, with viable E. coliO157:H7 still being detected in 25 g of cheese after 158 days. Cheese made with 1 CFU/ml of milk showed a reduction in E. coli Ol57:H7 to 1 or &lt;1 CFU/g in 60 days, with no E. coli being detected in 25 g of cheese at 158 days. However, both treatments resulted in the survival of E. coli O157:H7 during manufacture and for more than 60 days of curing at 2.75 to 3.76% salt in the moisture phase.

Viability of Escherichia coli O157:H7 in Fermented Semidry Low-Temperature-Cooked Beef Summer Sausage

1997 ◽  
Vol 60 (10) ◽  
pp. 1158-1162 ◽  
Author(s):  
MEHMET CALICIOGLU ◽  
NANCY G. FAITH ◽  
DENNIS R. BUEGE ◽  
JOHN B. LUCHANSKY
Keyword(s):  
Escherichia Coli ◽  
Low Temperature ◽  
Cold Water ◽  
Starter Culture ◽  
Escherichia Coli O157 ◽  
Internal Temperature ◽  
Direct Plating ◽  
E Coli ◽  
Log Reduction ◽  
Viable Cells

The population of inoculated Escherichia coli O157:H7 was monitored during the manufacture and storage of a semidry beef summer sausage processed by fermentation and cooking at a low temperature by heating to an internal temperature of 130°F (54°C). The all-beef batter (11% fat and nonmeat ingredients) was inoculated with the commercial starter culture Pediococcus acidilactici HP (≥8.6 log CFU/g of batter) and a five-strain mixture of E. coli O157:H7 (≥7 log CFU/g) and then hand stuffed into 2.5-inch (64-mm) diameter fibrous casings. The sausages were fermented at an initial temperature of 85°F (29°C) to a final temperature of 105°F (41°C) over ca. 13 h at 80% relative humidity (RH) to pH 4.6 or pH 5.0. After fermentation to pH 4.6, the internal temperature of the chubs was raised to 130°F (54°C) instantaneous over 3.6 h at 60% RH. After fermentation to pH 5.0, the internal temperature of the chubs was raised to 130°F (54°C) over 3.6 h at 60% RH and the chubs were maintained under these conditions for 0, 30, or 60 min. he chubs were cold water showered for 15 min and then chilled at 39°F (4°C) for 6 h before being vacuum packaged and stored at 39°F (4°C) or 77°F (25°C) for 7 days. Regardless of the target pH, fermentation alone resulted in only a 1.39-log CFU/g decrease in pathogen numbers. However, fermentation to pH 4.6 and heating to an internal temperature of 130°F (54°C) instantaneous reduced counts of E. coli O157:H7 by ≥7.0 log units to below detection levels (&lt;10 CFU/g). Pathogen numbers remained below levels detectable by direct plating, but viable E. coli O157:H7 cells were recovered by enrichment of samples during sausage storage at either refrigeration or abuse temperatures. In contrast, fermentation to pH 5.0 and heating to an internal temperature of 130°F (54°C) instantaneous resulted in a 3.2-log-unit decrease in counts of E. coli O157:H7. No appreciable reductions in pathogen numbers were observed thereafter following storage at either 39°F (4°C) or 77°F (25°C) for 7 days. Fermentation to pH 5.0 and heating to an internal temperature of 130°F (54°C) instantaneous followed by holding for 30 or 60 min resulted in about a 5- or 7-log reduction, respectively, in pathogen numbers. For chubs held for 30 min at 130°F (54°C), pathogen numbers decreased to 2.02 and &lt;1.0 log CFU/g at 39°F (4°C) and 77°F (25°C), respectively, after 7 days; viable cells were only observed by enrichment after storage at 77°F (25°C). For chubs held for 60 min at 130°F (54°C), pathogen numbers remained below levels detectable by direct plating, but viable cells were recoverable by enrichment after 7 days at both storage temperatures. These data will be useful guidelines to manufacturers for developing processing conditions to further ensure the safety of this category of fermented sausages relative to food-borne pathogens such as serotype O157:H7 strains of E. coli.

Validation of Pepperoni Process for Control of Shiga Toxin–Producing Escherichia coli

2012 ◽  
Vol 75 (5) ◽  
pp. 838-846 ◽  
Author(s):  
KATHLEEN A. GLASS ◽  
CHARLES W. KASPAR ◽  
JEFFREY J. SINDELAR ◽  
ANDREW L. MILKOWSKI ◽  
BRIAN M. LOTZ ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Limit Of Detection ◽  
The Other ◽  
Direct Plating ◽  
E Coli ◽  
Log Reduction ◽  
Three Samples ◽  
Processing Steps

The objective of this study was to compare the survival of non-O157 Shiga toxin–producing Escherichia coli (STEC) with E. coli O157:H7 during pepperoni production. Pepperoni batter was inoculated with 7 log CFU/g of a seven-strain STEC mixture, including strains of serotypes O26, O45, O103, O111, O121, O145, and O157. Sausages were fermented to pH ≤4.8, heated at 53.3°C for 1 h, and dried for up to 20 days. STEC strains were enumerated at designated intervals on sorbitol MacConkey (SMAC) and Rainbow (RA) agars; enrichments were completed in modified EC (mEC) broth and nonselective tryptic soy broth (TSB). When plated on SMAC, total E. coli populations decreased 2.6 to 3.5 log after the 1-h heating step at 53.3°C, and a 4.9- to 5-log reduction was observed after 7 days of drying. RA was more sensitive in recovering survivors; log reductions on it were 1.9 to 2.6, 3.8 to 4.2, and 4.6 to 5.3 at the end of cook, and at day 7 and day 14 of drying, respectively. When numbers were less than the limit of detection by direct plating on days 14 and 20 of drying (representing a 5-log kill), no more than one of three samples in each experiment was positive by enrichment with mEC broth; however, STEC strains were recovered in TSB enrichment. Freezing the 7-day dried sausage for 2 to 3 weeks generated an additional 1- to 1.5-log kill. Confirmation by PCR revealed that O103 and O157 had the greatest survival during pepperoni productions, but all serotypes except O111 and O121 were occasionally recovered during drying. This study suggests that non-O157 STEC strains have comparable or less ability than E. coli O157 to survive the processing steps involved in the manufacture of pepperoni. Processes suitable for control of E. coli O157 will similarly inactivate the other STEC strains tested in this study.

How Homo economicus lost her mind and how we can revive her

2018 ◽  
Vol 41 ◽  
Author(s):  
Peter DeScioli
Keyword(s):  
Economic Thought ◽  
History Of Economic Thought ◽  
Homo Economicus ◽  
Economic Theories ◽  
Target Article ◽  
History Of ◽  
The Mind ◽  
And Behavior

AbstractThe target article by Boyer & Petersen (B&P) contributes a vital message: that people have folk economic theories that shape their thoughts and behavior in the marketplace. This message is all the more important because, in the history of economic thought, Homo economicus was increasingly stripped of mental capacities. Intuitive theories can help restore the mind of Homo economicus.

The parent-offspring microbiome and neurobehavioral development

2019 ◽  
Vol 42 ◽  
Author(s):  
Jeffrey R. Alberts ◽  
Christopher Harshaw ◽  
Gregory E. Demas ◽  
Cara L. Wellman ◽  
Ardythe L. Morrow
Keyword(s):  
Mammalian Species ◽  
Social Emotional ◽  
Behavioral Measures ◽  
Neurobehavioral Development ◽  
Emotional Function ◽  
Neurobehavioral Outcomes ◽  
Methodological Approaches ◽  
And Behavior

Abstract We identify the significance and typical requirements of developmental analyses of the microbiome-gut-brain (MGB) in parents, offspring, and parent-offspring relations, which have particular importance for neurobehavioral outcomes in mammalian species, including humans. We call for a focus on behavioral measures of social-emotional function. Methodological approaches to interpreting relations between the microbiota and behavior are discussed.

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