39. Methods of technological treatment of meat and meat products (heat treatment, chilling, freezing) Flashcards
What is aim of heat treatment?
- Microbial stabilization (elimination of pathogenic bacteria)
- Development of sensory characteristic (color, flavour, structure, texture)
- Stabilization of the structures
- Limiting effects of overcooking (water loss, degradation of organoleptic characteristics)
What is temperature for optimal flavor of meat?
60-65*C
What are the 3 cooking methods?
Water, steam oven or smoking
Q40
What are the pros with cooking in water?
- Shorter cooking time
- Good heat exchange
- Good regulation of temperature
What are the cons with cooking in water?
- Less hygienic
- Water bath takes up spaces
- Cooking loss from direct contact with water
What are pros/cons with cooking in a steam oven?
- Less heat exchange
- Longer cooking time
- Temperature differences in the oven cause irregular cooking.
What are the 7 types of smoking that can be done to meat?
(Simple steps)
- Cold smoke
- Warm smoke
- Hot smoke
- Composition of smoke
- Liquid smoke
- Smoking house
- Smoking generators
What is aim of meat chilling?
- Slow down the metabolic rate of meat and contaminating microbes (prevent action of MOʼs & extend shelf life)
- The goal is to decrease the core temperature from 39°C to 7°C ASAP and still maintain the weight.
In what temp should the different meat types be chilled?
Red meat, white meat, offal, fish
Red meat: 7C
White meat: 4C
Offal: 3C
Fish: 0C
What are the 3 methods of chilling?
Air chilling
Water chilling
Combined chilling
What is air chilling dependent on?
Temperature, velocity, RH, air exchange, weight and fat amount
What are the air chilling methods?
- Rapid cooling of meat
- Ultrafast cooling of meat
- Shock cooling of meat
What are the requirements for rapid air chilling?
Temperature: -1 to +2*C
Humidity: 85 - 90%
Time: 12-24h
What are the requirements for ultrafast air chilling?
Temperature: -5 to - 8*C
Humidity: 90%
Time: 2h
What are the requirements for shock cooling (air chilling method)?
Temperature: -14 to -25*C
Humidity: 95%
Time: 2h
What are some pros with water (immersion bath) chilling method?
Shorter cooling time, cheaper
How do chilling and cold storage affect meat quality in terms of ripening, weight loss, proteolysis, and lipolysis?
Ripening: During cold storage, enzymatic processes (like proteolysis) break down muscle proteins, improving meat tenderness and flavor.
Weight loss: Meat loses moisture due to evaporation and drip loss, especially if storage conditions are not optimal.
Proteolysis: Breakdown of muscle proteins (by enzymes like calpains and cathepsins), which contributes to tenderness.
Lipolysis: Breakdown of fat into free fatty acids, which can impact flavor positively (aged meat) or negatively (rancidity if oxidation occurs).
Why is cold shortening done? At what temperature?
Causes muscle contractions instead of rigor mortis, causing a net ATP deplatation,
which leads to Ca2+ ions leaking through the sarcoplasmic reticulum, and then increasing ATPase activity.
Temperature is lowered to 11°C fast, and pH is til kept above 6,
What must be labelled on freezing product?
Date of freezing
What are the temperatures for normal freezing temp, deep freezing and long term storage
- Normal freezing temp: - 12*C
- Deep freezing: -18*C
- Long term storage: -18*C for 2years
What are some pros with freezing?
- Prevent MO action
- Extend shelf-life
- Prevent parasitic diseases (trichinella and sarcocystis)
What are different freezing methods used?
- Contact freezing
- Air freezing
- Cryogenic freezing
How does contact freezing work and what freezing medium is used?
Meat is placed on a cold surface (plate, rotating plate, or continuous belt) to freeze it quickly by direct contact.
Medium - CaCl or MgCl
What is air freezing, and what are the different types?
Air freezing uses cold air to freeze meat and can be done in:
- Chamber freezers (static air, slower freezing)
- Tunnel freezers (airflow speeds up freezing)
- Continuous belt freezers (efficient for large-scale freezing)
