Staphylococcus aureusreservoirs during traditional Austrian raw milk cheese production

2014 ◽  
Vol 81 (4) ◽  
pp. 462-470 ◽  
Author(s):  
Georg Walcher ◽  
Monika Gonano ◽  
Judith Kümmel ◽  
Gary C. Barker ◽  
Karin Lebl ◽  
...  
Keyword(s):  
Physicochemical Parameters ◽  
Production Chain ◽  
Staph Aureus ◽  
Cheese Making ◽  
Milk Samples ◽  
Processing Level ◽  
Bulk Milk ◽  
Microbiological Methods ◽  
Culture Independent ◽  
Cheese Production

Sampling approaches following the dairy chain, including microbiological hygiene status of critical processing steps and physicochemical parameters, contribute to our understanding of howStaphylococcus aureuscontamination risks can be minimised. Such a sampling approach was adopted in this study, together with rapid culture-independent quantification ofStaph. aureusto supplement standard microbiological methods. A regional cheese production chain, involving 18 farms, was sampled on two separate occasions. Overall, 51·4% of bulk milk samples were found to beStaph. aureuspositive, most of them (34·3%) at the limit of culture-based detection.Staph. aureuspositive samples >100 cfu/ml were recorded in 17·1% of bulk milk samples collected mainly during the sampling in November. A higher number ofStaph. aureuspositive bulk milk samples (94·3%) were detected after applying the culture-independent approach. A concentration effect ofStaph. aureuswas observed during curd processing.Staph. aureuswere not consistently detectable with cultural methods during the late ripening phase, but >100Staph. aureuscell equivalents (CE)/ml or g were quantifiable by the culture-independent approach until the end of ripening. Enterotoxin gene PCR and pulsed-field gel electrophoresis (PFGE) typing provided evidence that livestock adapted strains ofStaph. aureusmostly dominate the post processing level and substantiates the belief that animal hygiene plays a pivotal role in minimising the risk ofStaph. aureusassociated contamination in cheese making. Therefore, the actual data strongly support the need for additional sampling activities and recording of physicochemical parameters during semi-hard cheese-making and cheese ripening, to estimate the risk ofStaph. aureuscontamination before consumption.

scholarly journals Survey of pyrethroid, macrocyclic lactone and antibacterial residues in bulk milk tank from Minas Gerais State, Brazil

2017 ◽  
Vol 37 (2) ◽  
pp. 97-104 ◽  
Author(s):  
Lidia C.A. Picinin ◽  
Isabela M. Toaldo ◽  
Rodrigo B. Hoff ◽  
Fernando N. Souza ◽  
Mônica O. Leite ◽  
...  
Keyword(s):  
Minas Gerais ◽  
Veterinary Drugs ◽  
Veterinary Drug ◽  
Screening Methods ◽  
Production Chain ◽  
Milk Samples ◽  
Bulk Milk ◽  
Minas Gerais State ◽  
Confirmatory Tests ◽  
Bulk Milk Tank

ABSTRACT: A survey of veterinary drug residues in bulk milk tank from Minas Gerais State, Brazil, was carried out through a broad scope analysis. Here, 132 raw milk samples were collected at 45 dairy farms in Minas Gerais from August 2009 to February 2010, and analyzed for 42 analytes, comprising pyrethroids, macrocyclic lactones and antibacterials, using liquid chromatography coupled with mass spectrometry in tandem mode and gas chromatography with electron capture detection. Within all milk samples, at least one veterinary drug residue was identified in 40 milk samples (30.30%) by confirmatory tests, whereas 16 samples (12.12%) showed the presence of at least two residues. With regard to the Brazilian maximum residue levels, 11 milk samples (8.33%) were non-compliant according to Brazilian Legislation. The veterinary drugs detected in the non-compliant milk samples include penicillin V (one sample), abamectin (one sample) and cypermethrin (nine samples). Furthermore, the antibacterial screening methods failed to identify most of the positive samples that were detected by confirmatory tests, leading to a large discrepancy between the screening and confirmatory antimicrobial tests. Thus, the present study indicated that the veterinary drugs residues still represents a great concern for the milk production chain.

Addition to Thermized Milk of Lactococcus lactis subsp. cremoris M104, a Wild, Novel Nisin A–Producing Strain, Replaces the Natural Antilisterial Activity of the Autochthonous Raw Milk Microbiota Reduced by Thermization

2014 ◽  
Vol 77 (8) ◽  
pp. 1289-1297 ◽  
Author(s):  
ALEXANDRA LIANOU ◽  
JOHN SAMELIS
Keyword(s):  
Lactococcus Lactis ◽  
Great Part ◽  
Raw Milk ◽  
Control Treatment ◽  
Lactococcus Lactis Subsp ◽  
Milk Samples ◽  
Bulk Milk ◽  
C 30 ◽  
Sterilized Milk ◽  
Cheese Production

Recent research has shown that mild milk thermization treatments routinely used in traditional Greek cheese production are efficient to inactivate Listeria monocytogenes and other pathogenic or undesirable bacteria, but they also inactivate a great part of the autochthonous antagonistic microbiota of raw milk. Therefore, in this study, the antilisterial activity of raw or thermized (63°C, 30 s) milk in the presence or absence of Lactococcus lactis subsp. cremoris M104, a wild, novel, nisin A–producing (Nis-A+) raw milk isolate, was assessed. Bulk milk samples were taken from a local cheese plant before or after thermization and were inoculated with a five-strain cocktail of L. monocytogenes (approximately 4 log CFU/ml) or with the cocktail, as above, plus the Nis-A+ strain (approximately 6 log CFU/ml) as a bioprotective culture. Heat-sterilized (121°C, 5 min) raw milk inoculated with L. monocytogenes was used as a control treatment. All milk samples were incubated at 37°C for 6 h and then at 18°C for an additional 66 h. L. monocytogenes grew abundantly (>8 log CFU/ml) in heat-sterilized milk, whereas its growth was completely inhibited in all raw milk samples. Conversely, in thermized milk, L. monocytogenes increased by 2 log CFU/ml in the absence of strain M104, whereas its growth was completely inhibited in the presence of strain M104. Furthermore, nisin activity was detected only in milk samples inoculated with strain M104. Thus, postthermal supplementation of thermized bulk milk with bioprotective L. lactis subsp. cremoris cultures replaces the natural antilisterial activity of raw milk reduced by thermization.

scholarly journals Staphylococcal food poisoning from sheep milk cheese

1989 ◽  
Vol 103 (3) ◽  
pp. 449-458 ◽  
Author(s):  
F. J. Bone ◽  
D. Bogie ◽  
S. C. Morgan-Jones
Keyword(s):  
Food Poisoning ◽  
Detailed Examination ◽  
Human Consumption ◽  
Staph Aureus ◽  
Sheep Milk ◽  
Bulk Milk ◽  
Clinical Illness ◽  
The Uk ◽  
First Time ◽  
Cheese Production

SUMMARYCheese made from sheep milk was implicated in food-poisoning incidents in December 1984 and January 1985. Bacteriological examination of batches of cheese failed to reveal a viable pathogen but enterotoxin A produced byStaphylococcus aureuswas present. This was the first time that enterotoxin was detected in a food produced in the UK which was associated with poisoning and from which viableStaph. aureuscould not be isolated. Subsequent detailed examination of milk, yoghurt and cheese from the same producer revealed that contamination withStaph. aureuswas associated with post-infection carriage as well as clinical illness in ewes on the farm. Strains producing enterotoxin A were still intermittently present in the bulk milk used for cheese production nearly 2 years afterwards, apparently in the absence of clinical illness in the sheep. The possible effects of heat treatment are discussed. Any changes in legislation should cover all non-human mammalian milk used for human consumption.

The Effectiveness of Amoxicillin and Cefalexin in Two Species from Staphylococcus and Bacillus Isolated from Bovine Mastitis in Sudan

2019 ◽  
Author(s):  
Reem Rabie Mohammed Salih
Keyword(s):  
Bacillus Cereus ◽  
Bovine Mastitis ◽  
Bacillus Coagulans ◽  
Staph Aureus ◽  
Milk Samples ◽  
Sensitivity Tests ◽  
Bacillus Spp ◽  
Staphylococcus Spp

In this study 60 milk samples collected from mastitic cows to isolates and identify bacterial agents. The percentage of isolates was as follows: Staphylococcus spp 52%, Bacillus spp 26%, Enteroccocispp 3%; microccus 3%, Nesseria 2%, Branhamella 3%, Clostridium 1%, Bordetella 2%, Enterobacteria 3%, Aeromonas 4%, Fusobacterium 1%. In sensitivity tests used two antibiotics Amoxicillin and Cephalexin against two highest isolates in this study (Staph spp and Bacillus spp and found: Staph. aureus and Staph. hyicus were resistant to Amoxicllin and cephlaxin relatively, Bacillus coagulans and Bacillus cereus were susceptible to Amoxicllin and cephlaxin.

Proteolysis detection in milk: II. The effect of preincubation of raw and laboratory pasteurized bulk milk samples on tyrosine value and its relationship with bacterial populations

1973 ◽  
Vol 40 (3) ◽  
pp. 383-392 ◽  
Author(s):  
H. S. Juffs
Keyword(s):  
Major Contributor ◽  
Milk Supply ◽  
Bacterial Populations ◽  
Milk Samples ◽  
Bulk Milk ◽  
Upper Limit ◽  
Principal Source ◽  
Before And After

SummaryA study is reported of the effect of preincubation of raw and laboratory pasteurized bulk milk samples on the tyrosine value (TV) of milk and its relationship with bacterial populations. For raw samples, mean TVs before and after preincubation for 20±2 h at both 25 and 30 °C differed (P < 0·001). After preincubation at 30 °C, the TV of 47 % of raw samples exceeded that considered to represent the upper limit of variation in the TV of a normal bulk milk supply. At this temperature, however, there was no indication that proteolytic psychrotrophs were a major contributor to increased TV. With preincubation of raw samples at 25 °C, an increase to above the upper limit of variation occurred in only 20 % of samples; however, proteolytic psychrotrophs appeared more active at this temperature. In similar samples preincubated after laboratory pasteurization, large increases occurred in TV after 20 ±2 h at 30 °C, while at 25 °C the increases were much smaller and of the order found for preincubated raw samples. The results showed, however, that nonpsychrotrophic bacteria were also the principal source of proteinase giving rise to increased TVs in laboratory pasteurized samples.

scholarly journals PP-040 Real-time PCR assay for identification of Brucella abortus in bulk milk samples in Iran

2010 ◽  
Vol 14 ◽  
pp. S36-S37 ◽  
Author(s):  
S. Moshkelani ◽  
M. Javaheri Koupaei ◽  
S. Rabiei ◽  
A. Doosti
Keyword(s):  
Real Time ◽  
Brucella Abortus ◽  
Real Time Pcr ◽  
Pcr Assay ◽  
Milk Samples ◽  
Bulk Milk

Characterization of Serratia species and qualitative detection of Serratia marcescens in raw and pasteurized milk by an analytical method based on polymerase chain reaction

2021 ◽  
Vol 67 (2) ◽  
pp. 3453-3464
Author(s):  
Evelin Korcz ◽  
László Varga ◽  
Zoltán Kerényi
Keyword(s):  
Serratia Marcescens ◽  
Bacterial Species ◽  
Relevant Literature ◽  
Inhibitory Effect ◽  
Test Methods ◽  
In Vitro Assays ◽  
Pasteurized Milk ◽  
Milk Samples ◽  
Microbiological Methods

Serratia species are opportunistic pathogenic microorganisms primarily known as nosocomial infectious agents, which can also cause food quality problems. The appearance of the extracellular pigment-producing Serratia marcescens in cow’s milk causes its red discoloration, posing a challenge to the dairy industry and food certification laboratories. The detection of the bacterium by conventional procedures based on microbiological methods is time-consuming and labor-intensive, and in many cases does not lead to satisfactory results due to the competitive inhibitory effect of the accompanying microflora. Following the analysis of the relevant literature, the published endpoint PCR methods and the primers used for the detection of S. marcescens were evaluated in in silico and in vitro assays, and then the procedure was tested on farm milk samples. Using the method, a total of 60 raw and pasteurized milk samples were analyzed, more than half of which (i.e., 32) were identified as S. marcescens positive. The significance of our work is mainly represented by the application of the published test methods in food industry practice. Our results highlight to the importance of detecting this bacterial species.

642. Penicillin in milk: II. The incidence of penicillin

1956 ◽  
Vol 23 (3) ◽  
pp. 342-347 ◽  
Author(s):  
N. J. Berridge
Keyword(s):  
Significant Proportion ◽  
Cheese Making ◽  
Milk Samples ◽  
Significant Interference

An examination of over 5000 milk samples has shown that penicillin is frequently present. Its concentration, however, is usually below the level which is believed to be necessary to cause significant interference in cheese-making, but a significant proportion of the samples contained more than a third of this quantity. This suggests that conditions under which difficulty would arise are not remote.

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