Ksu meat preservation
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Transcript of Ksu meat preservation
Meat
Preservation
Meat Putrefication
• Meat is putrefied due to the action of bacteria , moulds , yeasts.
• To grow and proliferate the organisms temperature is necessary. Due to this classify the organisms,
• 1-Pschyrophiles: have optimum temperature range of -2 to 7*c.
• 2-Mesophiles: have 10 to 40*c.• 3-Thermophiles: have 43 to 66*c. • Organisms also need water for growth.
Why Preserve Meat???
• Delays product spoilage
• Extends life of the product
• Improves product quality
Preserve Meat
• To preserve the meat temperature must be
• 1- : -2*c by chilling or freezing.
• 2- : 66*c by pasteurization , cooking or sterilization.
• To preserve the meat , remove the water by dehydration , freezing , curing.
Types of Preservation Techniques
• Freezing• Cooking• Dehydration• Chemical • Fermentation• Irradiation
Types of Meat Preservation1. Drying-
Removal of water from meat.
2. Heating- Kills bacteria if temperatures reaches 160 degrees.
3. Refrigeration- Slows the growth of bacteria
4.4. Freezing-Freezing- 20 degrees below zero eliminates bacterial growth
5. Acidification- Low pH retards bacterial growth
Types of Meat Preservation6. Irradiation-
Low levels kill bacteria in fresh meat products
7. Canning- Packaging meat into sealed containers and heating meat to kill bacteria
8. Curing- Compounds make meats inhospitable to microbial growth.
9. Salting and Sugaring- Prevents microbial growth
10. Smoking- Forms antibacterial chemicals to the meats surface
Typical Methods of Food Preservation:
• High temperature– Pasteurization kills spoilage and pathogenic
organisms (1864 – Pasteur)– Longer temperatures and times can sterilize
foods
• Low temperature– Refrigeration or freezing inhibits microbial
growth
Typical Methods of Food Preservation:
• Dehydration– Air drying
• Chemical preservatives– Inhibitors of organism growth such as salt,
sodium nitrite, and propionates
• Bactofugation– Removing bacteria from liquids by
centrifugation
Freezing
• Optimum temperature (0°F or lower)
• Meat freeze at -1.4*C• Works by completely stopping
enzyme activity & inhibiting spoilage microorganisms
BacteriaYeastsMolds
Freezing
• REMEMBER: Thaw meat at refrigeration temps or in the microwave
• DO NOT THAW AT ROOM TEMPS
How long with frozen meat last?
• Beef – 12 months
•Pork - 6 months
• Lamb – 6-9 months
• Poultry – 3-6 months
Disadvantages of freezing
• Frozen meat stored too long become dry , less palatable and rancid.
• After thawing it is less durable than fresh-killed or chilled meat.
• When frozen meat is thawed it weeps or drips which consist mainly of water, salt, protein and demaged blood corpuscles.
• Loss of weight due to drip in beef is up to 3% while in mutton , lamb or pork loss is less than beef.
FREEZER BURN
• Yellowish –brown or whitish areas seen on the surface of frozen meats.
• It is due to excessive drying of the surface.• Phenomenon involves the formation of a • condensed layer of the muscular tissue just
under the surface. this prevents moisture coming to the surface from the depth of the meat.
Chilling of meat
• It is useful when meat is stored for short time up to 35 days.
• It is kept at b/w -1.4*c and 1*c preferably in the dark as light has the effect of oxidizing fats.
• Atmosphere keep dry to prevent the mould formation
• 5-10%CO2 helps to prevent the growth of mould and bacteria.
• It is important that temperature does not reach -1.4*c otherwise meat is frozen..
Cold shortening
• Toughness develops in lamb carcasses, if they are exposed to low temperature within about 16 hours after slaughtering
• pH is about 6.3 and ATP levels are high ,lowering of the temperature causes the muscle to contract. It starts normally at 15*c and become greater down to 0*c.
• Beef carcass do not chilled quickly b/c of the thickness of the muscles.
• Due to rapid fall in the pH there is no problem of cold shortening in the pig carcass.
Cooking
• Works by heating products to high temperatures to kill microorganisms
• 2 types of cooking– Pasteurization– Sterilization
Pasteurized Cooking
• Products are cooked to 150-170°F
• Kills most (but not all) microorganisms
• Product must be REFRIGERATED
• Example: “Hotdogs”
Sterilized Cooking• Products cooked under pressure to
250°F
• All microorganisms killed
• Products are shelf stable
• Example: Canned Hams
Smoking
• - Meat, fish and some other foods may be both preserved and flavored through the use of smoke, typically in a smoke house. The combination of heat to dry the food without cooking it, and the addition of the aromatic (phenolic)hydrocarbons from the smoke preserves the food.
Vacuum packing
• Vacuum-packing stores food in a vacuum environment, usually in an air-tight bag or bottle. The vacuum environment strips bacteria of oxygen needed for survival, slowing spoiling.
Canning
• Canning: food is sealed in a container such as a can or glass jar and heated to kill all living organisms, or at least to ensure that there will be no growth of residual organisms.
• Acidic foods should be heated to 100°C, whereas nonacidic foods should be heated to 121°C. Properly canned foods may not be sterile b/c heating them for the time required might alter the foods’ taste and nutritional value.
• Since some of the anaerobic organisms that can grow in cans are from the genus Clostridium, food from a can that is visibly altered, ex. bulged can, should not be eaten.
Dehydration
• Oldest forms of preserving meat
• Works by removing water from the product– water is required by all
microorganisms to grow NO WATER = NO GROWTH
Dehydration
• Dehydrate by air drying, heating, or freezing
• Example: “Beef Jerky”
Chemical
• Chemicals inhibit microorganism growth
–Salting or curing draws moisture from the meat through a process of osmosis.
• Examples– Salt– Sodium Nitrite– Sodium Lactate
Chemical Preservatives
• Sodium Benzoate
• Sorbate
• Proprionates
Chemical Preservatives• Sulfur Dioxide
• Nitrates and Nitrites
• BHA/BHT
Chemical
• Other benefits:– Add flavor to the product– Improve product shelf life – Develop a pink cured-meat color
• All Chemicals added to meat are FDA approved
Fermentation• Works by changing sugar into acid
• Acid prevents microorganisms from growing
• Tangy flavor and special texture developed
• Example: “Pepperoni”
Modified Atmosphere Preservation
• MAP – Modified Atmosphere Packaging• Carbon Dioxide• Types
– Hypobaric– Vacuum Packaging– MAP– Equilibrium Modified Atmosphere– Controlled Atmosphere Packaging
MAP Equipment
Irradiation• A new process to make
food SAFER!!!!
• Works by exposing meat to radiant energy
• Destroys most (but not all) microorganisms
“Radura” sign on labels
Irradiation
• Reduces spoilage
• Irradiated meat is still nutritious
• Irradiated meat needs to be COOKED
• IRRADIATED MEAT IS SAFE TO EAT!!!!
Irradiation unit
The 5 Factors in the Curing Process
1. Flavor
2. Color
3. Tenderness
4. Preservation
5. Yield
Preservation
3 main ingredients to preservation process
1. Salt
2. Sugar
3. Nitrite
FlavorFlavor is the primary reason consumers purchase meat more
than once
Salt- Predominant flavor in most processed meats
Sugar- Used to reduce the harshness of the salt flavor
Nitrite- Provide a characteristic flavor you recognize as a ham flavor
Smoked- Contains a smoke flavoring rather than being traditionally smoked
Color and Tenderness
Color- If nitrate is used the meat will take on a distinctive red color.
Tenderness- The type of process will affect the tenderness of the meat.
Examples: Jerky the meat is dry and tough
Ham usually fairly tender
YieldWhen meat products are cooked and smoked, some water and juices are lost,
making the product weigh less, thus reducing the product’s value.
1. Moisture- Helps prevent moisture loss during cooking and smoking
2. Increased Profits- Adds weight to products increasing the price of the product.
3. Curing- Used to deliver cure ingredients into the fresh meat prior to curing.
The Curing Process
Non-Meat Ingredients
• Not meat!!!
Ingredients
• Increase product yield
• Aid in color, texture or flavor development
• Increase product shelf-life
• Increase process efficiency
Questions• Please contact Dr. Elizabeth Boyle
or Ryan Timm at (785)532-1247email: [email protected]
Please contact Dr.M.Arshad.Javid email: [email protected]
OR • Call your county extension office