L18: Safe water and Applied Food Microbiology Flashcards
Which laws determine potable/wholesome water?
Water Supply Regulations 2010/Water Act 2003
What is detailed by the water supply regulations?
The samples, the frequency and what analyses should be performed e.g. microbiological, aesthetic, chemical
What does water aesthetics include?
Colour, turbidity, taste
What does chemical contents of water include?
Inorganic, organic eg pesticides
What does the microbiological content of water include?
Coliforms, Clostridia, Crypto
Per what amount of water are microbes measured by?
Per 100ml, apart from crypto which is per 10L
What is aquifer/ground water?
Old water slowly filtered
What are the components of aquifer/ground water like?
Good microbiological and chemical properties
What are two examples of surface water?
Reservoirs and rivers
What can surface water be contaminated by?
Agricultural run-off, eutrophication, floods, humans, nitrates from farming, heavy metals from roads
Who inspects water?
Drinking Water Inspectorate
When can water sampling be done?
During treatment, storage or at customer taps
What does water sampling frequency depend on?
Sample point and test
What are the usual hazards from waste water?
Biological or chemical e.g. slurry/nitrates from farms, drugs, SRM, contaminated abattoir material, organic pollutants from industry
Which pollutant can cause cancer in beluga whales?
PAH (persistent organic pollutants)
What can some boat paints do to molluscs?
Become sterile due to endocrine disruption
In the UK, who controls discharge into sewers?
Water companies
Which law controls water discharge into sewers?
Water Industry Act
Who audits discharge into sewers?
Trade Effluent Inspectors
What is specified by the Water Industry Act?
Levels and what is permitted
Who produces a Consent to Discharge?
Businesses
Who controls and monitors what is discharged to water courses after it has been treated?
The Environment Agency
Who sets the standards for what is discharged to water courses after it has been treated?
EU Water Framework Directive
What two things are controls on what is discharged to water courses after it has been treated important for?
Bathing water and shellfish hygiene
What causes Legionnaire’s disease?
Legionella pneumophila
What is mild Legionnaire’s called?
Lochgoilhead disease, Pontiac fever
What does severe Legionnaire’s cause?
Pneumonia
What is mortality if severe Legionnaire’s?
10-25%
Where do you get Legionnaire’s from?
AC, spa, ingestion, biofilms
Which animals has Legionnaire’s cases been reported in?
Cattle
What is temperature growth range for Legionnaire’s?
Optimum at 40, active from 20
What disease outbreak has been caused by dams?
Schistosomiasis
What disease outbreak has been caused by irrigation projects?
Japanese B encephalitis
What is the reservoir of Japanese B encephalitis?
Pigs
What do toxic metabolites of Cyanobacterium cause in UK livestock and pets?
Occasional enteritis and death
What three things enhance eutrophication?
Raised phosphate, raised nitrogen, increased surface water temperaure
What bacteria can be present in a biofilm?
Mycobacterium, pseudomonas, legionella, fusobacteria, staphylococcus
What cfu/ml does a biofilm contain?
> 10,000
What is EU guideline of cfu/ml?
100
What is legislation on pharmaceutical contaminants like?
Little
What is the level of pharmaceutical contaminatants like?
Low grade
Who is responsible for testing water regularly?
FBO, water distributor
Who must audit water testing?
OV
Who must audit and inspect microbiological sampling of animal-derived food?
The OV
Is it the law to do microbiological sampling of animal-derived foods?
Yes
What are the two types of microbiological criteria?
Food safety criteria, process hygiene criteria
What does process hygiene criteria do?
Ensure production is operating properly
What must happen if food safety criteria are not met?
Must withdraw/recall
What must happen if process hygiene criteria are not met?
Find out why and ensure it does not happen again
What is an ACC?
Aerobic colony count (bacteria that can survive on the surface of carcases)
How does ACC give an idea of the keeping quality of the meat?
Includes spoilage organisms
How do enterobacteria get on the surface of a carcase?
Faecal or environmental contamination
What aspects of the microbiological tests must an OV audit?
Sampling method, bacteriological method, results, response to adverse events
What three things must the microbiological tests be done on?
Carcases, minced eat, environment
Which foods are checked for Listeria?
Baby food, cheese, pate, salmon
What is minced meat tested for?
Salmonella
What is the maximum allowed level of Salmonella?
None - must be absent
How many sample sites must you do for each carcase?
4
Which is the only species which is microbiologically sampled after it has been chilled?
Poultry
What are two methods of taking microbiological samples?
Excision or wet-dry swab technique
What three things do you culture for?
Total viable count, enterobacteria, Salmonella
What are critical limits like for samples taken by swabs?
20% lower
What are criteria like in baby food?
Higher
What do you test for in fish?
Histamine
What do you test for in live bivalve mollsucs?
E Coli
What do you test for in dry infant formula?
E Sakazaki
What do you test for in cheese?
Staph
What do you test for in ready to eat foods?
Listeria
What do you test for in meat, cheese, butter, eggs, sprouted seeds
Salmonella
How long must the OV keep records for?
18 months
How many weeks of data must the OV have available?
The last 13 weeks
How many consecutive satisfactory results must you have before moving to fortnightly testing?
6
What happens if you are outside the critical limits?
Must implement and document corrective procedures and return to weekly sampling
What must happen before an environemental sample can be taken?
Must be visibly clean
How many environmental samples do you need every 2 weeks?
10
What are two methods of taking environmental samples?
Agar plate or peptone broth wetted swabs
What length must each environmental sample cover?
20cm
