Meat and Alternatives Flashcards
Meat consumption in Canada most prevalent to least
Feed then chicken pork fish turkey lamb
Sources of fat:Fresh meat
beef, pork, lamb
8.5% is lower than what comes from processed meat (lunch meat, sausages, hot dogs) fat is a concern here
Largest sources of fat in Canadian diets
Fats and oils, milk products, and then bakes good
Reduction in fat in pork
Decrease due to how the meat is trimmed (removing more of the fat on the outside edge of the meat) reductions also come from how the animals are fed and housed.
Factors that impact fat content in animals
they are under less stress than indoors so they can take the energy from their good and convert it to muscle mass. Kinds of grain also impacts level of fat. Raising and taking care of animals impact fat content of animals
Primary source of beef
The steer 2/3 (15-24 months)
Other sources of beef
Heifers, cows, bulls
When is veal produced?
3 week to 4 month old animals
Veal vs calves age
Calves 4-9 months veal 3/4
Why is vela milk and tinder
They are not old so haven’t had time to develop muscle mass
Steer?
Castrated male and cassation helps them be more calm
Heifers
Younger female
Cow
Mature female
Bull
Not castrated not in grocery stores but in food processing the corned beef (tougher and not tender)
Pork primary soruce
Hog more than 4 months more than 55 kg
What is a pig defines as?
Less than 4 months old and less than 55 points
What is a pig defines as?
Less than 4 months old and less than 55 points
Gender of hog
Casterated male or female
Increased safety of pork
Less likely to be exposed to trichinellosis because they are stored indoors, so it can be undercooked. Technically pork products can be juicier and not as dry = much better experience as a consumer
Lamb primary source
Less than one and 90% of market
Other sources of lamb include
Spring and mature sheep
Feed to muscle conversion
Slightly better in pork and chicken than in beef. They also reach market in less time so not feeding them for that long
Red vs white meat chicken
Red muscle is highly active (drumsticks, legs, wings) contains more lipid, more active so needs vascularization which impacts the colour. Breast meat does not need vascularization so will be white and a good option for lower fat diets. Lower in fat so normally more dry is texture
Red pigment
Myoglobin gives meat its red colour
Why do fish have more pUFA
PUFAs have good percentages in fish because they will be consuming algae in the ocean whcih contributes to heart healthiness of fat
More lipid in red or white muscle?
Red
Grading of Canadian beef
Prime, AAA, AA
Prime grade
Abundant marbling throughout meat
Where is fat distributed in body?
- First In the around the interior organs (kidneys have fat pads surrounding them) related to insulation and physical protecting for kidneys.
- Second Subcutaneous fat for protection, insulation,
- Third will be within the muscle or intramuscular fat
Most meat in Canada
AA because AAA is rare
Characteristics of prime
Abundant marbling so seeing lots of grains of fat in the muscle so when you grill it the meat will be perceived as more juicy from fat and from salivation during chewing of the product.
Where does the characteristic of juiciness come from?
More about what happens within the oral cavity rather than what the marbeling in the meat does
Grade AAA
Small amount of marbling throughout mean and won;t seem as juicy
Grade AA
Found mostly in stores with flight marbling throughout meat
Kobe beef characteristics
Over the top marbling from Japan comes
Connective tissue
Bundles of muscle fibres and vascularization of tissues and connective tissue that will surround muscle fibers and be involved with attachment from muscle to bone (tendons)
connective tissue with age?
Amount of connective tissue increases with age which is why older animals will be tougher and less valued.
Cuts of beef and tenderness
Related to where the cuts of meat come from
Regions of body with higher activity will be touched (shoulder)
Brisket will be coming from this. Brisket is stewed so that it can be tenderized
Higher value meat:
Ribs, flank steak, sirloin
Cholesterol content of meat and fish
75 mg/ 100 g serving
Meat vitamins and minerals
B complex vitamins like thiamine, riboflavin, niacin, B6 and B12 and fat soluble vitamines
Why does tissue of animals become more yellow as they age
deposition of carotenoids because they build up in fat tissue which occurs overtime
Quaternary structure of muscle
Actin and myosin
LOOK UP SARCOMERE STRUCTURE
Sarcomere at rest vs completely contracted
When the muscle is handing it allows for stretching of the muscle making it more tender shortened will be tough and undesirable
Myotome
Pattern of musculature of bony fish
Post mortem changes in meat
Rigor and pH loss of ATP
Rigor occurs when
Within 6 to 24 hours post death
Change in pH
converting the glycogen to lactic acid which contributes to decrease in pH
Hallmark events of muscle contraction?
Release of calcium from the sarcoplasmic reticulum calcium bings to troponin causing actin to tighten up the myosin heads bind to the actin
Loss of ATP result
Anaerobic metabolism
What is happening with loss of ATP
Energy will be supplied to ATP and as the ATP is used up that is what is going to contribute to initiation to rigor Mortis
The myosin heads will interact with the actin the troponin components and the state of contraction or rigor will occur for about 24-48 hours.
What helps muscle recover out of rigor?
if there is any existing enzyme activity in the muscle
Enzyme can cleave actin from Z line which will allow for sarcomere to stretch or relax from that contraction
What happens once rigor is recovered?
the muscle is going to be tender again because it is no longer contracted
Cold shortening
Too rapid cooling of carcass
What happens in cold shortening
ATP still present and too rapid cooling with damage the sarcoplasmic reticulum which will release the calcium ions so the muscle will contract (myosin interacting with actin) will end up with shortened contracted muscle that will be rough and stays cold so the muscle may not be able relax again.
Result of cold shortening
You have a tough product and less provide because muscle is shortened. Undesirable low quality product that consumer will not pay regular prices for.
Thaw rigor
This muscle has undergone freezing pre rigor. Immediately post mortem.
What happens once you start thawing product?
. Once you started to thaw product then the muscle will contract and it is severe or extreme resulting in 40-50% shortening of the muscle length. You have possibility for a very tough shortened contracted product. During freezing you can have damage to SR which allows the release of calcium upon thawing leading to the extreme contraction
Quality of treatment of animal and quality of meat
if you cause animals stress or unnecessary muscle movement, animals will have extra movement which will deplete the glycogen stores in the muscle.
What happens if you have less glycogen
If you have less glycogen which means you have reduced production of lactic acid which means the decrease in pH we expect will not happen. PH will be closer to neutral resulting in a darker colour to the muscle (much darker purple colour) and an unpleasant sticky characteristic or quality. Overall poor quality
Amount of myoglobin present in tissues
Beef most then lamb then pork
What is myoglobin oxidation state?
Related to oxidation state of iron bound to myoglobin
How can iron exist?
Iron can exist in one of two oxidation states Fe2+ and Fe 3+.
Oxymyoblin Colour
Bright red and Fe2+ association with oxygen
Myoglobin Colour
Fe 2+ and purple red due to reduced form of the iron
Metomyobolbin
If meat is forgotten in the fridge there may be a definite distinct change in the appearance of the meat and how have a brownish red or slight grey colour. No longer have iron in reduced state but it is now oxidized so loss of an electron making is Fe 3+ instead of 2+
Fat in chicken
subcutaneous fat 11%
Fat in water birds
21 - 28 more fat for insulation and protection
Chicken production primary soruce
Hen raised 6-8 weeks
Turkey production primary source
In the case of turkeys we know birds are raised to 17-20 weeks of age so larger
When will poultry undergo rigor?
4 hours to come out of rigor chicken and 12 for turkey
Fin fish
Salt and fresh water so anadromous
What are long chain PUFAs a reflection of in fish?
Bodies of water they spend their lives in
Salmon pigmentation
pink vs shanook salmon and difference in colour is shanook is more deep pink almost red and that different in pigmentation is associated to what the fish eat (smaller fish and seaweed algae) algae contains carotenoids which build up in tissue giving us the characteristic colours we see
Atlantic salmon
s colder than pacific that is why Atlantic salmon have higher fat content. Fat separated individual myotomes giving indication of fat content of Atlantic salmon. If it is farmed it will contain even more fat
Tofu making
We have dry soybeans then are soaked hull removed which removes a lot of fiber. Mashed to inactivate the trypsin inhibitors
If residual solids that is okara (not soluble and strained out which is the beginning parts of soy beverage or soy milk.
If you take the liquid and pasteurize and pack it you will have soy milk
If you take liquid and add calcium chloride or calcium sulphate that gives of coagulation and a semi soluble protein based gel that holds moisture which is our tofu
You can pressure and form into rectangles that we see on the shelves (pressing influences among of moisture you keep in
Shaping tofu
Lined with porous fabric (tofu cloth similar to cheese cloth)
Let tofu sit in there for the shape
Drainage holes allow for removal of moisture that influences ultimate texture of your product
Yuba
Can also have soy protein sheets that enclose mushrooms or other things in dim sum
Part of tofu making processes
Pouring in soy base once solids have been removed
Letting mixture sit creates a film that can dehydrate similar to the surface of milk
Is soy protein based and can be lifted out, removed, and dehydrated
