Dl: Preservation Of Meat

Question 1

Risk factors for contamination and spoilage and meat

Answer 1

• intrinsic factors of meat

- extrinsic processing

Question 2

Steps in ham production

Answer 2

• pig
• harvesting
• raw material intake
• injected with brine, massaged
• potted
• cooked/smoked
• cool
• packed, labelled, stored

Question 3

How is salmonella controlled on farm

Answer 3

• wearers and growers more than sows
• vague clinical signs (D+ dehydration septicaemia and CNS ARARE)
  > feaces, blood, tissue to dx
• source of organism may be in food and water
• may not be encouraged to call vet as clinical signs not very obvis
• most farms are salmonella +
  > ZAP (zoonosis action plan grading scheme)
• ZAP 1 vax available but not widely used
• EU legislation says we have to have a national control programme (hence monitoring ELISA test at abattoir and advice for farmers but minimal motivation for farmer)

Question 4

Control of salmonella at harvesting levels

Answer 4

> pre harvest
- withhold food? Full GIT more likely to burst, ^ feed intake will v salmonella load
- legislation on max withholding food times
harvest
- 2 knife method
- don’t cut gut
- separate sero+ and - differently (sero+ at end of day)
- don’t use plucks from sero+ , special clean
post
- heat treat sero+ carcasses (swab carcasses first)
- plug anus during dehairing and scalding (rarely done)
- cross contamination after scalding minimised

Question 5

Processing

Answer 5

> tenderising
- breaks down colagen
- pounding, enzymes, brining etc.
tumbling and massaging
- injected with curing salt solution , tumbling more violent than massaging
- improves water holding capacity
- heating after sets the proteins
curing
- salt or nitrate compounds (kills clostridium botulinum and improves colour)
- removes water and slows microbe growth
- salt >4% kills bacteria, rarely higher than 5 for taste

Question 6

Smoking curing and cooking

Answer 6

• smoking bacteriostatic only outside of meat (not very effective)
• flavour
• drying meat
  > cooling
• decrease microbe reproduction but don’t kill bugs already present
• cooking
• kill enzymes and microbes
• best to get rid of salmonella
• D value salmonella (time taken to kill 90% organisms) 60* for 1min

Question 7

Packaging and labelling

Answer 7

• MAP
• modified atmospheric packaging
• 30% co2 70% n2 processed meats
• 70% o2 30% co2 fresh meats

Question 8

Consumption

Answer 8

• wash hands
• gammon is uncooked ham
• fridge

Question 9

Why do we preserve meat

Answer 9

• delay spoilage, extend shelf life
• improve flavour
• promote safety