What Is Meat Science Flashcards
What is meat?
Flesh of an animal used as food
Are cattle, hogs and sheep native to the U.S.?
No, the meat industry in the U.S. is European based by explorers (colonial butchers)
When did exports start?
1641
What act was placed in 1906?
Meat inspection act
What is important to consumers about meat?
Safety, quality, and value
What is safety?
Zero tolerance by consumers
What three things can safety be broken down in to?
Pathogens, chemicals, and physical hazards
Pathogens include what?
E. coli, listeria, etc
What are the chemical elements included in safety?
Sanitizing agents, antibiotics, etc
What are some physical hazards?
Gloves, rings, wood, metal, etc
What is quality?
Summation of the characteristics of food that impacts processing functionality and consumer appeal
What four things can quality be broken down in to?
Palatability, nutritional value, appearance, and preservation
What is value?
Summation of market defined factors
What four things go into making something valuable to a consumer?
Safety, quality, composition and price
What drives the demand for meat?
Price, convenience, flexibility, consistency, and nutrition.
Is all meat consumed?
No
What are some types of food preservation?
Salting, smoking, etc.
What are colonial butchers?
Trained Europeans that started butchering for others.
Why did the meat industry move to more rural areas?
Closer to livestock production, automation reduced labor needs, and there was more infrastructure.
Demand for meat in the US is what?
Slowing down and there is a slow population growth.
World wide demand…
Exports are important, economic development, cultural preferences, traditions, and country of origin reputation.
What are the major components of meat and what percent do they each make up?
Water (75%), protein. (18.5%), fat (3%), and ash (3.5%).
What is water holding capacity (WHC)?
The ability of foods to immobilize water, structure gives ability to immobilize, and protein with charge will bind through electrostatic interactions.
What are the types of water in meat and what percent do each make up?
Bound (0.5-4%), immobilized (1-6%), and free (90-96%).
What is processing functionality?
Example: PSE pork is low quality due to the lack of whc
What are the major components of meat?
Water, protein, ash, and fat.
What percent (range) of water is in meat?
65-80%
What percent (range) of protein is in meat?
16-22%
What percent (range) of fat is in meat?
1.5-13%
What percent of ash is in meat?
3.5%
What is water holding capacity?
The ability of foods to immobilize water.
What is bound water?
0.5-4% water, doesn’t freeze, is not a solvent, mobility is greatly reduced.
What is immobilized water?
1-6% water, freezes slightly, reduced solvent, mobility is reduced.
What is free water?
90-96% water, some freezing, is a solvent, little reduction in mobility.
What is water activity?
Measuring the activity of water against distilled water, has a scale of 0-1.
What type of water has the water activity of 1?
Distilled water.
What has a water activity of 0.98-0.99?
Raw meat.
What are the functional properties of proteins?
Water binding, gelation, emulsification, viscosity, flavor binding, foaming, color.
What is a primary amino cid?
Amino acid sequence of proteins.
What is a secondary amino acid?
Helix, beta pleated sheets of proteins.
What is a tertiary amino acid?
3D structure of proteins.
Proteins are composed of ______.
Amino acids.
What is a globular protein?
Soluble in native environment and is an example of myoglobin.
What is a fibrous protein?
Elongated, largely insoluble, and connective tissue.
Why is a conjugated protein?
Protein combined with another compound (example: lipoprotein).
What does amphoteric mean?
Proteins can act as an acid or base depending on the pH
What is isoelectric point?
pH at which protein has no net charge.
What is the isoelectric point of meat?
5.1
What is the pH of muscle?
7.2
What is the pH of meat?
5.3-5.8
What is denaturation?
Protein unfolding, does not involve a change in primary structure.
What is degradation?
Specific cleavage of peptide linkage causing change in primary structure.
Flavor comes from _______ and _________.
Proteins and lipids.
What are lipids?
They are made of C,H,O; non polar; long term storage of energy; responsible for flavor in meat; texture; juciness.
What are sterols?
Component of membranes and forms of cholesterol.
What are triglycerides?
Majority of total lipids and a glycerol backbone with 3 fatty acids.
What do fatty acids deal with?
Saturation or double bonds, chain length or number of carbons, and double bond configurations.
What are saturated fatty acids?
Have no double bonds.
What are unsaturated fatty acids?
Have one or more double bonds.
The greater number of ________ the lower the melting point.
Double bonds.
The longer the chain , the higher the _________.
Melting point.
________ is the number of carbons present in fatty acids and is typically between 2-24 carbons.
Chain length.
What are cis bonds?
Same side, take up more room, and have a lower melting point.
What are trans bonds?
They are on the opposite or transverse side.
Changes in ____ can lead to changes in fatty acid profiles and in bacon quality.
Diet
What type of acid is C18:0 and has the highest melting point?
Steric acid.
What type of acid is C18:1?
Oleic acid.
What type of acid is C18:2 and has the lowest melting point?
Linoleic acid.
What has a glycerol backbone, 2 fatty acids, and 1 phosphoric acid?
Phospholipid
What is rancidity?
Production of off flavors and off odors.
What is oxidative rancidity?
Oxidation of unsaturated fatty acids (more unsaturated fatty acids = more prone to oxidation).
Why is hydrolytic rancidity?
Contributes to aroma (not necessarily bad).
What is saponification?
Indicates chain length (higher # = shorter chain).
What does soxhlet mean?
Fat/lipid content as a percent.
What does iodine value indicate?
Indicates saturation (higher # = more double bonds).
What measures oxidation?
TBARs
What is important for the conversion of muscle to meat, is muscle glycogen, and contributes to flavor?
Carbohydrates
What is the Maillard reaction?
Browning reactions, and is between amino and acids and reducing sugar.
What is hyperplasia?
Increase in muscle cell number and occurs prior to birth.
What is hypertrophy?
Increase in muscle cell size and occurs after birth.
What are some potential issues with modifying growth?
Speed, tenderness, and marbling.
What type of muscle has multiple nuclei, is striated, and voluntary?
Skeletal muscle.
What type of muscle has one nuclei, is not satiated, and is involuntary?
Smooth muscle.
What type of muscle has 1-2 nuclei, can be striated, and is involuntary?
Cardiac muscle.
Sarcomeres are the ________ of the muscle.
Functional unit.
