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FDSN524 Midterm 1

Vitamins Compounds essential for the metabolic process of animals; participate in reactions but not consumed (catalysts)
Name the fat soluble vitamins. A, D, E, K
How do human's get get most of their vitamin K? Intestinal bacteria
Vitamin K is required in the body for _________. blood clotting factors
Vitamin A is a crucial component of _________. vision
11-cis rentinal binds to ______ to form ________, which is important for rod cells and night vision. Light breaks down ______ and sends signal to the optic nerve. opsin, rhodosin, rhodosin
What is carotenemia? Excess beta-carotene in the blood
What does vitamin D deficiency lead to? Rickets; pliable bones
How does the body produce vitamin D? pre-vitamin D from sun > exposed skin convers to vit D > vit D converted to 25-hydroxyvitamin D in liver > kidneys convert to 1,25-dihydroxyvitamin D (hormone)
What does excess vitamin D lead to? Hypercalcemia, kidney stones, calcification of soft tissues.
What is the primary role of vitamin E? Antioxidant
What are free radicals? Molecules with an unshared electron
What can vitamin C deficiency lead to? Scurvy (bleeding gums, impaired wound healing)
What can a thiamine (B6) deficiency lead to? Beriberi (loss of appetite, cardiovasicular symptoms)
What is the role of riboflavin (B2) in the body? Energy metabolism; component of FAD and FMN cofactors
What can a riboflavin (B2) deficiency lead to? Cheilosis (inflammation/small crack on corners of mouth), dermatitis
What can deficiency in niacin (B3) lead to? Pellagra
What is the function of pyridoxine (vitamin B6) in the body? Coenzyme in aa metabolism; synthesis of heme
What is the function of folic acid (B9) in the body? Involved in nucleic acid synthesis
What can a folic acid (B9) deficiency lead to? Anemia, neural tube defects
What is the function of iron in the body? Part of hemoglobin in blood
What is the function of sodium and potassium in the body? Nervous system function
What is the function of magnesium in the body? Functioning of nerves and muscles
What is the function of iodine in the body? It is required for thyroid hormone.
Recommended Dietary Allowances (RDA) Amounts of essential nutrients considered adequate to meet the nutritional needs of most health people in the US
Daily Reference Values (DRV) A set of dietary references for fat, saturated fat, cholesterol, carbohydrates, protein, fiber, sodium, and potassium
Reference Daily Intake (RDI) A set of dietary references based on the RDA for essential vitamins and minerals and, in selected groups, protein
Daily Value (DV) Appears on food labels; made up of DRVs and RDIs
Fortification Addition of nutrients to render the food a "good" source; may include addition of nutrients not normally found in the food.
Enrichment Addition of nutrients in accordance with a standard identity as defined by the FDA.
Bioavailability The degree to which an ingested nutrient undergoes intestinal absorption and metabolic function in the body
What are the functions of fat in the body? Energy storage, insulation, cell membranes, etc.
What are the functions of fat in food? Texture, emulsions, flying, carrier of flavors/colors
What is the most common type of fat in both foods and the body? Triglycerides
Fatty acids Long chain carboxylic acid; building blocks for triglycerides and phospholipids
Glycerides Fatty acids esterified to glycerol (e. 2 fatty acids + glycerol = diglyceride)
Are short-chain fatty acids liquid or solid at room temperature? liquid
Are long-chain fatty acids liquid or solid at room temperature? solid
What is the difference between a monounstaurated fatty acid and a polyunsaturated fatty acid? Monounsaturated has one double bond, polyunsaturated has two double bonds
What is the difference between an omega-3 fatty acid and an omega-6 fatty acid? The location of the first double bond
What are the two essential fatty acids? alpha-linolenic, linolenic
Rancidity Spoiling of fats through oxidation
How can rancidity be reduced in foods? Adding antioxidants, limiting exposure to heat/light/oxygen, hydrogenation
What is "C" nomenclature? [number of C atoms]:[number double bonds] - eg. C18:6
What is "omega" nomenclature? omega-[position of double bonds from methyl end] - eg. omega-3,6,9
How are trans fats made? Hydrogenation of vegetable oils.
What are the ways of assessing oil properties? Refractive index, iodine value, melting point, peroxide value, color, polar material, fatty acid composition, trace metals, smoke point, melt point
T or F: The higher the melting point, the more stable the molecule. True
T or F: The longer the chain and the fewer the double bonds, the lower the melting point. False
T or F: Corn oil has a higher melting point than lard. False
Plastic range Temperature range over which a fat exhibits plasticity
What different methods are available for altering plastic range? Interesterification, hydrogenation, mixing different fats, adding emulsifiers
Interesterification Process of heating a fat in the presence of a catalyst to hydrolize the fatty acids and re-esterify them with glycerol
Superglycerination Process of incorporating 3-6% emulsifier into shortening to improve baking qualities
What are the advantages of hydrogenation? Decreases susceptibility to oxidation; raises melting point
What are the advantages of interesterification? Prevents large crystals; fat has wider plastic range
Autooxidation of lipids The oxidative deterioration of unsaturated fatty acids via an autocatalytic free radical chain mechanism
How is a lipid radical formed? Hydrogens are removed from the lipid closest to double bonds
Name the initiation mechanisms of autooxidation of lipids? Photosynthesized oxidation, metal catalysis, thermal oxidation, enzymatic oxidation
What is the difference between a primary and a secondary antioxidant? Primary: free radical acceptors that delay or inhibit the initiation/propogation steps Secondary: Do not convert free radicals to more stable products
T or F: The more time a food spends being fried in oil, the decrease in unsaturation. True
What is the general structure of a protein? NH2-CHR-COOH
Which proteins are considered amphiphilic? glycine, alanine, tryptophan
A protein at a low pH will be _______. protonated
A protein at a high pH will be ________. deprotonated
Isoelectric point pH at which the positive and negative charges on an amino acid are in balance (ie. zero net charge)
T or F: Proteins are least soluble at their isoelectric point. True
What are the essential amino acids? PVT TIM HALL
What is the name of the bond which links amino acids together to form proteins? peptide bond
What two atoms participate in a peptide bond? alpha-carbon on one amino acid and alpha-amino group on the other amino acid
T or F: The protein backbone unit consists of repeating N-C-C units. True
Name the non-covalent bonds in proteins. Van der Waals forces, electrostatic forces, hydrogen bonds
Name the covalent bonds in proteins. disulfide linkages, peptide bonds
Primary protein structure Linear sequence of amino acids linked via peptide bonds
Secondary protein structure Spatial arrangement of amino acid residues at certain segments of the chain; alpha-helix, beta-sheets, random
Random coil A secondary structure with no regular or ordered pattern along the polypeptide chain
Tertiary protein structure Polypeptide folds into a compact 3D form - usually globular or fibrous
Name examples of fibrous proteins. Collagen, actin/myosin
Name examples of globular proteins. Myoglobin, whey proteins, caseins
Quaternary protein structure Protein contains multiple polypeptide chains
Disulfide linkage Covalent linkage between two cysteine residues, forming cystine
What are the different functions of proteins in food? Texture, appearance, flavor, nutrition, toxicity
Denaturation Disruption of any of the higher order structures of the protein without disrupting the primary structure
What are different causes of denaturation? heat, acid, salts, mechanical action
What are the effects of denaturation? decreased solubility, loss of function, increased susceptibility to proteases
Where does gelatin come from? Collagen - connective tissue in animals
What are the steps of gel formation? Powder is dispersed in water and heated, gelatin cools and viscosity increases, liquid changes to viscoelastic solid
Acid Any substance that can donate a proton
Base Any substance that can accept a proton
What is the equation for the dissociation constant (pKa)? pKa = -log(Ka)
What is the difference between a weak and a strong acid? Strong acids have a larger extent of dissociation.
Total acidity Both ionized and unionized H+ atoms; aka titratable acidity/normality
Active acidity Ionized H+ atoms; = normality * rel. amount ionized; measured by pH
Normality [molarity][number of ionizable H+ atoms]
Molarity moles/L
What is the equation for pH? pH = -log[H+]
What is the Henderson-Hasselbalch equation? pH = pKa + log[A-]/[HA]
Equivalence point When chemically equivalent quantities of acid and base have been mixed
Catalyst Substance which changes the rate of a chemical reaction without appearing in the end products
Coenzyme A non-protein substance required by some enzymes as a co-factor; can be organic or inorganic
Energy of activation Energy needed for a reaction to proceed
What are some roles of carbohydrates in foods? Source of energy, sweetness, browning reactions
What are the two classifications for monosaccharides? aldoses and ketoses
What are the two classifications for polysaccharides? homo and hetero
Aldose A monosaccharide containing an aldehyde group
Ketose A monosaccharide containing a ketone group
What models are using to represent monosaccharides? Fischer projection, Haworth projection, chair conformation
D-configuration On a monosaccharide the hydroxyl (OH) group is to the right of the last stereocenter on a Fischer projection
What is the formula for determining the number of stereoisomers? 2^n where n is the number of chiral carbons in the molecule
Epimers Molecules which differ in configuration around one specific C-atom
Anomeric carbon The carbon atom apart of the carbonyl group
What is the difference between alpha and beta anomers? The OH group differs in their configuration around the amomeric carbon (alpha = right, down, axial; beta = left, up, equatorial)
Hemiacetal An aldehyde which reacts with an alcohol
Hemiketal A ketone which reacts with an alcohol
When the C1 aldehyde and C5 OH of glucose react, what happens? Cyclicization - forms an intramolecular hemiacetal (pyranose ring)
What are the two ways to form fructose? 6 member pyranose ring: C2 keto group with OH on C6 5 member furanose ring: C2 keto group with OH on C5
What larger molecules can glucose be found in? Sucrose, lactose, starch, glycogen, and cellulose
Which monosaccharide is the sweetest? Fructose
Which monosaccharide is an epimer of glucose? Galactose
How are glycosidic bonds formed? The hydroxyl group on one monosaccharide reacts with the hydroxl on another
What two monosaccharides make up lactose? glucose and galactose
What are some differences between alpha- and beta-lactose? alpha-lactose is more soluble, beta-lactose is hygroscopic (not suitable for forming tablets -> little commercial use)
What is the amorphouse form of lactose? It is non-crystalline and obtained by spray drying; very hygroscopic
Explain lactose intolerance? Lactase enzymes in the intestine are decreased; undigested lactose gets broken down by intestinal bacteria and causes gas/cramping
What two monosaccharides make up sucrose? glucose and fructose
What is invert sugar? Invert sugar is created by the hydrolysis of sucrose by microorganisms or acid and splitting into glucose and fructose
What is galactosylsucrose? Sucrose derivatives comprised of sucrose linked by glycosidic bonds to glycosyl units
Reducing sugar Sugars having free anomeric hydroxyl groups and can participate in chemical reactions
Name the reducing sugars. glucose, fructose, maltose
Cyclodextrin formed by soluble, partially hydrolyzed starch polymers; hydrophobic core and polar exterior
Name two purposes of cyclodextrins. bind flavors, lipids, and color compounds; bind undesirable constituents; to stabilize against chemical oxidation
Polyols not true sugars which lack a carbonyl group; sugar alcohols; can be formed by reducing sugars
What are unique properties of polyols? negative heat of solution - cooling sensation in mouth when consumed; does not undergo browning; lower calorie count/gram; non carcinogenic; slow GI absorption
Polysaccharide Complex carbs made up of several monosaccharides
What is starch made up of? glucose; amylose/amylopectin
What is the structural difference between amylose and amylopectin? Amylose has a linear structure which forms a helix; amylopectin has branches
Birefringence The refraction of polarized light by the intact crystalline regions give a "maltese cross" pattern which disappears upon heating/gelatinization
Describe the solubility of starch. Insoluble in cold water, more soluble in heated water; gelatinization point is where crystallinity is lost
Imbiption When starch granules swell when heated with water.
Describe the gelatinization of starch Imbiption, H-bonds break causing amylose to spill from the starch granule, the granules lose their integrity, when cooled, junction zones form between amylose and amylopectin, water is trapped forming a gel
What are factors affecting starch gelatinization? Temperature, agitation/stirring, addition of acid, addition of other ingredients, enzymes
Retrogradation Occurs when starch chains re-associate into an ordered strcuture > crystalline order
T or F: Short-term retrogradation occurs with amylopectin, long-term retrogradtion occurs with amylopectin True
Synersis As gel dehydrates, junction zones tighten and water is "squeezed" from the gel
Name three types of starches. Cornstarch, tapioca, potato
Name the four types of modified starches. Hydrolysis or acid-converted (low viscosity), cross-linked or cross-bonded (resisitant to shearing + greater heat tolerance), substitution or stabilization (prevents retrogradation + reduces synersis), physically modified (absorb cold water - pudding!)
Name the four types of resistant starches. RS1 RS2 RS3 RS4
What are resistant starches used for in foods? Increase fiber content
Where is glycogen stored in the human body? Liver and muscles
Glycogen is identical in structure to _________ but _______ occurs making it different. amylopectin, more branching
Glycogen can be hydrolyzed to _________. Glucose
What monosaccharide makes up cellulose? Glucose
The structure of cellulose is similar to _______ but _______ changes the 3D shape to be _________. amylose, glycosidic bonds, straight
Why is cellulose considered an insoluble fiber? Humans lack cellulase to hydrolyze beta 1->4 bond
What is carboxymethyl cellulose? chemically modified cellulose which does not occur naturally in plants; aka cellulose gum (increases water solubility/thickening agent)
What are pectic substances? cell cementing substance; linear polymers of galacturonic acid
Name three pectic substances. Propectin, pectinic acid, pectic acid
What are pectins? high-MW pectinic acids that are dispersible in water; classified as high methoxyl and low methoxyl
What is required for pectin jelly? Pectin, water, sugar, acid
What are gums? polysaccharide substances derived from plants; typically contain galactose
Gums are also known as __________. hydrocolloids
What are the functions of gums in foods? Gelation, viscosity, emulsification/stability, whipping, suspension, freeze thaw protection
What are some of the functions of water in foods? Ingredient, solvent, gelatinization of starch, plasticizer, microbial spoilage, medium for heat, cleansing agent
Sustainibility involved equitable distribution of _______ and ________. resources, opportunities
T or F: Water is the one molecule that does not have a dipole moment. False
T or F: Water can act as both an acid and a base. True
Equilibrium constant of water equation: Kw = [H3O+][HO-]/[H2O]^2=10^-14
T or F: Water may be adjusted to be alkaline to minimize corrosion of pipes and deposition of carbonates. True
Gibb's free energy equation: deltaG = H-TdeltaS
Specific heat The amount of energy (heat) per mass unit required to raise the temperature by 1 degree Celcius; Q=mcdeltaT (Q is energy, c is specific heat)
Latent heat The amount of energy (heat) required to bring about a phase change at constant temperature and pressure (L=Q/m)
Name the phase transition steps to go from solid to gas. Heat of fusion, latent heat of fusion, heat of vaporization, latent heat of vaporization, vapor
What is the physical state of water in the heat of vaporization stage? Liquid
Exothermic Product has less energy than the starting material
Endothermic Product has more energy than the starting material
T or F: In an endothermic reaction, the starting material loses heat and the surrounding material or environment gains heat. False
Sensible heat Heat that results in a change in temperature (measured with a thermometer)
Wet bulb temperature Temperature indicated by a moistened thermometer bulb exposed to the air flow; measured the extent of cooling as moisture dried from a surface
What are the advantages to wet bulb temperature? Measures true thermodynamic temp, determined relative humidity, psychrometric charts are available
T or F: The wet bulb temperature is always higher than the dry bulb temperature. False
Solvent Substance that dissolves solutes
Solute Substance dissolved in a solvent
Solution Composition of solute and solvent
Colligative properties of solutions Properties that depend on the number of molecule present (not nature or size) eg. vapor pressure, boiling point, osmotic pressure
Unsaturated solution A liquid that holds less solute than possible
Saturated solution A liquid that holds the amount of solute is can dissolve at a given temperature
Supersaturated solution A liquid that holds more solute than it can theoretically dissolve at a given temperature
T or F: For every mole of nonvolatile solute in 1000g of solvent, the boiling point is raised 0.52 degrees and the freezing point is lowered 1.86 degrees True
Molality moles/kg
Molarity moles/L
T or F: Freezing point is not affected by elevation. True
T or F: For every 960 ft above sea level, the boiling point decreases by 1 degree True
Bound water Cannot be removed by normal drying; no longer a solvent; no appreciable vapor pressure, only freezes at very low temperatures, needs high vacuum to be removed from tissues
Water activity Means of determining microbial stability in food; related to the rate of some chemical reactions in food; aw= sample vapor pressure/water vapor pressure
Vapor pressure Pressure that vaporized molecules product over the surface of a liquid
Water isotherm Relationship between water content and equilibrium humidity displayed as curve
Hystersis The time-bases dependence of a system's output on a present and past inputs
What is the aw value for bacteria (permitting growth) 0.91
T or F: Water activity is one means of determining microbial stability in food. True
Temperature of glass transition (Tg) The temperature at which a substance changes from a rubbery to a glassy state (eg. hard candy manufacture)
Water hardness mg/L of calcium carbonate
Temporary hard water Contains calcium bicarbonate or magnesium bicarbonate
Permanent hard water Contains calcium sulfate or magnesium sulfate
Softened water Water that has had calcium and magnesium ions removed
Distilled water Has most impurities removed by boiling and condensing the stream
Deionized water Impurities reduced by ion exchange resins and activate carbon filters
Name the steps in softening hard water 1. Boil 2. Add reactive compounds (forms insoluble caronate salts) 3. Use ion exhange (removes Ca or Mg in exchange for Na or H)
T or F: Water hardness is measured by the amount of sodium chloride the water contains. False
What does milk include? Emulsified fat globules, casein micelles/proteins, lactose and salts
Total milk solid All components of milk except water
Milk solids/Nonfat milk solids All components of milk solids except fat
What is the composition of milk? Fat (3.5-3.7%), protein (3.5%), carbs - lactose (5%), ash (0.7%), water (87%)
Milk is a rich source of _________ and contains 95% _______. Conjugated linolenic acid fat, triglycerides
What are the major proteins in milk? Caseins, whey proteins
Casein Makes up 80% of protein in milk, exists as micelles, collodal dispersion; alpha, beta, kappa, and gamma
Whey Remaining liquid after curds are precipitated during cheese making; contains water, whey proteins (soluble/easily denatured), water soluble vitamins, lactose, minerals
Name the milk enzymes. Alkaline phosphatase (used to check pasteurization), lipases (inacivated by pasteurization), proteases
Milk is a good source of _____, ______, and ______. Phosphorus, magnesium, niacin
Milk is an excellent source of _____ and _____. Calcium, riboflavin
What characteristics of the cow affect milk composition? Genetics/breed, age, season, storage of lactation, feeding, period of time between milking, physiological condition of cow
What are the steps in milk production? 1. Milking; 2. Cooling and storage; 3. Tank transportation to the processing plant; 4. Separation of cream and skim; 5. Recombination to make 1%, 2%, etc; 6. Homogenization; 7. Pasteurization; 8. Packaging; 9. Refrigerated storage/distribution
Homogenization Reduction of milk fat globule size to eliminate creaming; milk forced through small openings under pressure
Milk fat globule is the form of _____ fat in milk. emulsified
Pasteurization can be performed at: Low temp longer time, high temp shorter time, ultra high temp
How do we test for proper pasteurization? Alkaline phosphatase should be inactivated
T or F: High fat products yield less reactivated phosphatase. False
Name other routine milk tests: Added water (check freezing point), antibiotics, bacteria, somatic cell counts
What do high counts of somatic cells in milk indicate? Some type of illness and immune response in cow
What effect does heat have on each of the following: pathogenic bacteria, enzymes, proteins, flavor? Pathogens - destroyed Enzymes - inactivated Proteins - denatured Flavor - loss or cooked flavor induced at >74 degrees
When milk is heated, a "skin" forms on the surface. What causes this and how can it be controlled? Water evaporates from the surface, concentrating protein which entraps fat and calcium. Cover the container or place a foam on the milk surface
Explain the effect of the following treatments on milk: freezing, exposure to direct sunlight, lipase activity of bacteria, left at room temp for 12 hours Freezing - can be done for 3-4 months; casein has limited stability Exposure to direct sunlight - oxidative rancidity Lipase activity of bacteria - hydrolytic rancidity Left at room temp - lactic acid bacteria produce acid > souring
How is milk treated for lactose intolerant people? Treated with enzyme lactase to hydrolyze lactose to glucose and galactose
Cream an oil in water emulsion that separates from whole milk upon standing (~30% fat)
What does churning cream do to make butter? Disrupts fat globule membrane and causes fats to coalesce. Flavor compounds: lactones and butyric acid
What microorganisms are used to make yogurt? S. thermophilus and L. bulgaricus
What microorganisms is kefir fermented with? L. Caucasus, S. kefir, T. kefir - contains 1% alcohol
Filled milk Milk fat is replaced with fats from other sources other than milk
Imitation milk Both milk fat and milk proteins are replaces with less expensive ingredients
Non-fat dry milk Spray-dried processed skim milk
Instant non-fat dry milk Wetted, agglomerated and re-dried non-fat dry milk (flavor is better)
Evaporated milk Milk heated to remove 60% of water, then homogenized and canned; 8% milk fat, 26% milk solids
Sweetened condensed milk Milk is pasteurized and 50% of water is removed; 44% sucrose added as a preservative; 8.5% milk fat, 28% milk solids
Cheese characteristics are affected by: types of microorganisms, temperature at ripening, humidity, length of ripening
Overrun Increase in volume of ice cream due to air
overrun equation overrun = [volume of ice cream - volume of mix]/volume of mix
The Jungle by Upton Sinclair (Chicago) prompted the creation of _______. The Food Safety and Inspection Service
Name the three types of muscle. Striated (skeletal), smooth (viceral/organs), cardiac (viceral)
Myofibril muscle bundles composed of actin and myosin
Stromal Watery connective tissue proteins in collagen, elastin, and reticulin
Sarcoplasmic Pigments and enzymes
Endomysium Thin connective sheath that covers actin and myosin
Give the hierarchy of muscle. myofibil>fiber>bundle of fibers>muscle
The thin filament is _____ and the thick filament is _______. Actin, myosin
The sarcoplasmic reticulum forms ____ on either side of the T-tubules forming a _______. Terminal cisternae, triad
T or F: The sarcoplasmic reticulum stores Ca++ when the muscle is not contracting. True
Name the major steps of muscle contraction (1-5). 1. Message from nerve 2. Nerve terminal releases acetyl choline 3. Acetyl choline diffuses to muscle cell membrane and binds receptors 4. Receptors cause cell membrane to "leak" - Na out K in 5. Membrane depolarization spreads across T-tubules
Name the major steps of muscle contraction (6-9). 6. T tubules cause Ca release on sarcoplasmic reticulum 7. Troponin changes shape and moves tropomyosin > myosin binds actin 8. Myosin heads move and muscle shortens (release ADP) 9. Ca is pumped back into the sarcoplasmic reticulum and muscle relaxes
How does electrical stimulation increase tenderness? Muscles contract and use up ATP > acceleration of glycolysis; proteolytic enzymes are released
What is the pI of meat? ~5.2
What is used to increase the water holding capacity of meat? Phosphate (alkaline) > increases negative charges of the protein so that water can bind
What happens when post-mortem meat is left to sit for too long? Rapid pH drop > fibrous and dry meat, protein denaturation
PSE pale, soft, exudative in ~45 minutes
DFD dry, fibrous, dark in 1-2 hours
What is the composition of meat? water, protein, fat, carbs, minerals
Stroml proteins insoluble, holds organs together, contribute to poor meat quality (eg. collagen and elastin)
T or F: Connective tissue (collagen, tendons, strap meat) increase the tenderness of the meat product. False
Name the sarcoplasmic proteins Enzymes, mitochondrial proteins, myoglobin
Myoglobin heme ring with iron as the core - attached to globin protein by histidine
What are the differences between hemoglobin and myoglobin? Hemoglobin carries O2 to blood, myoglobin stores O2 in muscles; myoglobin has higher affinity for oxygen
Reduced myoglobin will give ______ meat, oxymyoglobin will give ______ meat, and metmyoglobin will give ____ meat. purple, bright red, brown
T or F: Myofibrillar proteins contain all essential amino acids and have excellent digestibility. True
How can lipid oxidation of meat be prevented? Freeze meat rapidly after slaughter, bind to phosphates (oxidative catalyts), bind to antioxidants (BHA. BHT, TBHQ, tocopherols)
T or F: Quality grades are not given for pork and are voluntary. True
Humane Slaughter Act Animals must be unconcious before exsanguination; approved stunning methods include captive bolt, electric shock, carbon dioxide, and gunshot
T or F: In kosher slaughter, a rabbit cuts the meat after stunning the animal. False
T or F: In Halal slaughter, the meat must not come in contact with pork. True
Why is nitrite added in meat curing/smoking? To inhibit C. botulinum spores.
What are the ingredients used in curing/smoking? Salt, sugar, nitrite, vitamin C (speeds color change), alkaline phosphates (decreases shrinkage), spices, water
What are the factors for color after curing/smoking? myoglobin content, pH, amount/uniformity of nitrite, microbiological condition, post-processing exposure to light/oxygen
What are the ingredients in sausage? Meat, water, salt (preservation, flavor, solubilize actin/myosin), nitrite ascorbate and erythrobate (convert metmyoglobin and nitrite to myoglobin and NO), sugar, antioxidants (prevent fat oxidation), phosphates, GDL, mold inhibitors, MSG, sodium lactate
Meat emulsion Protein emulsifying agent in which protein unfolds and hydrophobic parts point towards lipid and hydrophilic part towards continuous phase - myosin is best emulsifying protein, collagen is worst
What can cause unstable emulsion? Over chopped meat, heating, too much collagen
What pathogens are of concern in meat? Salmonella, E. coli, C. jejuni, C. botulinuim, S. aureus, etc.
Why is the suggested minimum temp of whole muscle cuts lower than ground meat? Pathogens are on the surface in whole cuts, but mixed in in ground meat.
Poultry Domesticated birds kept for meat or eggs; include chicken, turkey, ducks, quail, etc.
Rock Cornish game hen 5-7 weeks old turkey, up to 2lbs
Broiler/Fryer 9-12 weeks old chicken, 2-2.5 lbs
Roaster 3-5 months old chicken, 3-5 lbs
Capon <8 months old chicken, male, 4-8 lbs
Hen ~12 months old chicken, female, 4-8 lbs
Fryer (turkey) <16 weeks old turkey, 4-8 lbs
Young hen/Tom 5-7 months old turkey, 8-14 lbs
Yearling/Tom <15 months old turkey
Mature or old turkey >15 months old turkey
Antemortem inspection check bird for illness of injury
Post mortem inspection After stunning, bleeding, scalding, plucking, and evisceration
What factors are considered when grading poultry? Condition or wholesomeness (no feces, feathers, bruises, etc.), class (age/sex), quality (# defects, amount of meat, color)
What are the Grade A standards for chicken? Free of deformities, well fleshed, free of feathers/feces, max diameter of cuts/tears = no more than 1.5 inches, no borken or missing joints (except wing tips/tail), little discoloration
How many birds (chicken and turkey) can be found in a grow-out house? Chicken - 25,000/house Turkey - 5,000/house
What essential amino acids are poultry fed? Lysine, methionine
Free Range traditional house with access to outdoors
Pastured/pasture raised Raised outdoors using movable enclosures
T or F: No hormones have been approved by the USDA for use in turkeys and chickens True
Evisceration cutting of the abdominal cavity and removing of the entrails
Scalding dipping the poultry carcass into hot water for the purpose of removing the cuticle (outer layer of skin)
When is the tenderness of poultry optimal? 2-2.5 hours after post-mortem, where there is a pH drop
Bologna and wieners Emulsion of meat and fat which is cooked to form a gelled product
Giblets edible internal parts of the poultry including liver, gizzard, and heart
How is oxidative rancidity measured for poultry? TBA (TBARS), head-space GC - TBA > 1 > rejected
PSE Pale Soft Exudates; protein denaturation due to a combination of high temp and fast pH drop after death; caused by rough handling, excitement, incomplete stun/kill, or genetic reasons
What are some poultry quality concerns? Bone residue, susceptibility to oxidation, chilling method can affect, susceptibility to microbial growth
Water can absorb _____ from the air to become acidic. carbon dioxide
Water may be adjusted to become _____ to minimize corrosion of pipes and deposition of carbonates. alkaline
Created by: goberoi