meat and meat products-canning, smoking and curing.ppt

meat preservation methods

1. Preservation of meat
Processing and preservation of meat
chilling
freezing
smoking
irradiation
cooking
canning
curing
1

2. 2
1.Chilling
Storage at 2-5
0
C
Relative humidity is kept 90%
slows down the microbial growth and
enzymatic
as well as chemical reaction
Shelf life of 5-7day

3. 3
2.Freezing
Storage temperature- -18
0
C to-20
0
C
Freezer burn: occurs due to progressive surface
dehydration resulting in the concentration of meat
pigment on the surface,
Freezing can be slow or rapid
Rapid freezing is desierable

4. 4
4.Irradiation
EM radiation are used
They destroy the microorganism by
fragmenting their DNA and causing
ionisation of inherent water.
Gamma rays are commercially used
50-100k rad dose—increases shelf
life of poultry by 19day

5. 5
5.Cooking of meat—thermal processing
cooking
Mild heating
•Below 100
0
C
•58-75
0
C is pasteurization
•Heating beyond
100
0
c to achieve
commercial sterility
•Shelf life of 2 year in cans
and 1 year in retort pouch
• Meat is then refrigerated

6. 6
3.Smoking
Provides bacteriostatic effect and a characteristic smoky
flavor.
Preservation is due to surface dehydration, lowering of
surface pH and antioxidant property of smoke
Aldehyde contributes most of the colour.
Phenol acts as bacteriostatic, formaldehyde as bactericidal.

7. 7

8. 8
6.Canning
Process of preservation by thermal sterilization of a product held in a
hermetically sealed container
Shelf life of at least 2 years at ambient temperature
Meat Preperation Preperation of gravy
Filling in cans
precooking (70
0
C for 15-30min)
Either manually or
mechanically
6.Canning
Process of preservation by thermal sterilization of a product held in a
hermetically sealed container
Shelf life of at least 2 years at ambient temperature
Meat Preperation Preperation of gravy
6.Canning
Process of preservation by thermal sterilization of a product held in a
hermetically sealed container
Shelf life of at least 2 years at ambient temperature
Meat Preparation Preparation of gravy

9. 9
cooling
retorting
Double seaming
Exhausting of air
Adjustment of
headspace
It minimise the strain
on the can seams due to
expansion of air during
heating
High temperature and
pressure (HTST or LTLT)
30
0
C-40
0
C
Labelled, storage and
marketed

10. 10

11. 11
7. Curing of meat
Done for specific colour and flavour development and for preservation
Curing ingredients—NaCl, NaNo
3,NaNo
2 and sugar
•Role of Nacl
Act by dehydration and alteration of osmotic pressure
Chloride ions directly act on microbes
Slows the action of photolytic enzymes

12. 12
Role of sodium nitrate and sodium nitrite
Served to stabilize the attractive colour and impart characteristic cured flavor
Colour reaction of cured meat:
NO
3 NO
2 NO

NO+Mb NoMMb NoMb


nitrosyl haemochrome
Reduction
Absence of light and air
Nitric oxide metmyoglobin
Nitric oxide
myoglobin
Heating or
smoking
(pink colour pigment)

13. 13
Permitted level of nitrate-500ppm and nitrite-200ppm.
Nitrites are bactericidal to Clostridium botulinum.
Nitrates and nitrites also retard the development of
rancidity.
Role of sugar:
Good food for nitrate reducing bacteria and
flavor and preservation