1. Welcome To Our Presentation
Group Members
Liton Chandra Barman
Tushar Ahmed
Jalal Uddin
2. MEAT PRESERVATION TECHNIQUES
The purpose of meat preservation is to add to the length of time that meat is
fresh, healthy, and bacteria free for human consumption. Meat is preserved
using many different processes. The process a specific meat is preserved under
is largely determined by what the meat will be used for when it is consumed.
Whatever the process, meat preservation is in place to save those who consume
the meat from contracting food-borne diseases
3. Why Preserve Meat
1. Delays products spoilage
2. Extends life of the products
3. Improves product quality
5. FREEZING
# Since the time frame of “world war 2” freezing has become most popular way to preserve meat
Temperature: Ideal temp.(-55ºc)
Commercially(-29ºc)
Domestically(-18ºc)
Works by stopping enzyme activity&
microbial growth of bacteria ,yeast & moulds
Almost 98% of water freezes at -20ºc
Complete crystal formation occurs at -65ºc
Fast freezing produce better quality than low freezing
Microbial growth stops at -12ºc
6. Disadvantage of freezing
During slow freezing formation of large ice crystal damage the cell and results in
a protein denaturation
Sometimes the texture of meat changed by this process
Duration of frozen meat lasting
Beef -12 months
Lamb- (6-9months)
Poultry-(3-6 months)
Pork-6 months
8. CHILLING
It is necessary to reduce the temperature of carcass immediately after evisceration to 4ºc within
4 hours of slaughtering
Two types : 1] Immersion chilling:
The product is immersed in chilled(0-4c)water
2] Air chilling:
Carcasses are misted with water in a room with chilled air .
Air chilling procedure is safer than the water chilling procedure with respect to
microbiological count .
It helps to prevent denaturing of proteins .
10. CANNING
Canning is the process of applying heat to foods that sealed in a jar in order to destroy any
microorganisms that can cause food spoilage
Mainly two types: 1) Water bath canning
2)Pressure canning
For meat we generally use pressure canning that produces steam at 240c temperature
During the canning process air is driven from the jar and a vacuam is formed as the jar cools and
seals.
12. DRYING
Drying may be done for the single purpose of dehydrating fresh meat for extension of storage
Drying & fermentation must go hand in hand to achieve the desired flavour and shelf life
Generally two types: 1)Sun drying
2)Solar drying * Tunnel dryer
*Multi collector dryer
Temperature: 70º-80ºc
13. Disadvantage of drying
Continuous evaporation and weight losses during drying causes changes of the shape of meat
through shrinkage
Meat pieces become smallest,thinner & darken in color
Texture of meat also changes from soft to firm to hard
14. IRRADIATION
Irradiation does not make foods radioactive, compromise nutritional quality, or noticeably
change the taste, texture, or appearance of food. In fact, any changes made by irradiation are
so minimal that it is not easy to tell if a food has been irradiated.
Food irradiation (the application of ionizing radiation to food) is a technology that improves
the safety and extends the shelf life of foods by reducing or eliminating microorganisms and
insects. Like pasteurizing milk and canning fruits and vegetables, irradiation can make food
safer for the consumer. The Food and Drug Administration (FDA) is responsible for regulating
the sources of radiation that are used to irradiate food
15. PROCESS OF IRRADIATION
There are three sources of radiation approved for use on foods.
Gamma rays are emitted from radioactive forms of the element cobalt (Cobalt 60)
or of the element cesium (Cesium 137). Gamma radiation is used routinely to
sterilize medical, dental, and household products and is also used for the radiation
treatment of cancer.
X-rays are produced by reflecting a high-energy stream of electrons off a target
substance (usually one of the heavy metals) into food. X-rays are also widely used
in medicine and industry to produce images of internal structures.
Electron beam (or e-beam) is similar to X-rays and is a stream of high-energy
electrons propelled from an electron accelerator into food.
16. ADVANTAGE OF IRRADIATION
Prevention of Foodborne Illness – to effectively eliminate organisms that
cause foodborne illness, such as Salmonella and Escherichia coli (E. coli).
Preservation – to destroy or inactivate organisms that cause spoilage and
decomposition and extend the shelf life of foods.
Control of Insects – to destroy insects in or on tropical fruits imported into the
United States. Irradiation also decreases the need for other pest-control
practices that may harm the fruit.
17. SMOKING
Smoking, as a mode of food preservation, is probably as old as cooking with fire.
Heat and smoke infuse a delicate flavor into fish, ham, poultry and meat and can
prevent the growth of microbes. While smoking done right is a very effective form
of food preservation, care must be taken to avoid contamination and food-borne
illness.
18. TYPES OF SMOKING
Hot Smoking
Hot smoking is done in the smokehouse or more modern electric kilns, usually over a short
period of time, just until the meat is cooked. The meat is cooked and smoked at the same
time over a burning fire or electric elements of a kiln.
Cold Smoking
“Cold Smoking” is done over a much longer period of time, e.g. 12-24 hours, over a
smoldering fire (below 85°F). Since foods are held in the temperature danger zone, rapid
microbial growth (40-140°F) could occur.
Liquid Smoke
Many consumers and commercial operations use liquid smoke to add smoke flavor to their
foods. Liquid smoke has advantages over traditional smoking in that it can be more
precisely controlled and the smoke flavor is instantaneous.
19. Advantages Of Smoking
Kills bacteria and slows growth of other types of bacteria
Adds some flavor to foods
Prevents fats from developing a terrible taste
Changes color (makes the food pleasing to the eye)
Can last longer in shelf life
21. Salting or Curing
salted meat is preserved or cured with salt.Salting,either with
dry salt or brine,was a common method.
Salt inhibits the growth of microorganisms by drawing water out of
microbial cells through osmosis. Concentrations of salt up to 20%
are required to kill most species of unwanted bacteria.
22. Advantage:
Makes water unavailable for microbial growth. Process does not destroy nutrients.
Disadvantage
Produces concentrated form of food. Inhibits microbial growth & autolytic
enzymes. Retains most nutrients.
23. Dehydration
Dehydration, in food processing, means by which many types of food can be
preserved for indefinite periods by extracting the moisture, thereby inhibiting
the growth of microorganisms.
Advantage
It’s the most nutritious way to preserve food – enzymes, vitamins, and
minerals aren’t destroyed by high canning temperatures.
Dehydrating food is a quick and easy way to preserve food.
Glass, plastic, or metal air-tight food containers can be used to store your
dehydrated fruit, vegetables, and meat.
Dried food doesn’t need to be refrigerated.
24. Disadvantage
Dehydrated foods have different properties than fresh ones, and they can be less
healthy.
Dehydration is a process that removes water, dehydrated foods are higher in
calories per ounce than their fresh counterparts.
It can be high-Sugar.
