AnSc 201
What is necessary for maintaining milk quality during storage and handling?
-Cool temp under 40degrees F -sanitary -odor free environment -No exposure to fluorescent lighting or sunlight
Liquefaction
-Loss of CO2 from albumen into atmosphere -Albumen binds less water -Yolk enlarges from water from albumen, becomes runnier -By adding CO2 to atmosphere helps reduce liquefaction
What factors does a consumer consider in determining egg quality?
-Sound shell- not cracked/broken all uniform -clean shells- free from imperfection -freedom from blood and meat spots -freedom from off-flavors-storing in odd places -Uniform size, shape, and color -Uniform yolk color -large amount of firm albumen
fiber structure
-cuticle in all wool fibers; scaly outer layer -cortex is needle like cells; ortho is soft, elastic and para is hard, less elastic. These determine the crimp of the wool fiber.
Primary Follicle
1st to develop, arranged in groups of 3, they are fully emerged at birth, accessory structures present, appear in bundles w/ Secondary fibers
Reduced fat milk
2% and lowfat 1%
Poultry lipids
2/3 unsaturated 1/3 saturated
condensed milk
7.5% fat 25% SNF water removed by preheating mainly used for industrial purposes
Egg Content
74% water 26% Dry matter 13% Proteins 11% Fats 1% carbohydrates/minerals
Chemical composition of meat
75%-water 19%- protein 4%-lipids 1% carbohydrates/minerals
Grade A milk
92% of US fluid milk- class 1
Skim milk
< 0.5% fat
what are the fat soluble vitamins in milk?
A, D, K, E- influenced by animal diet
What causes a "cowy" or "barny" flavor? Prevention?
Absorbed(transmitted) causes this flavor. Caused by transfer from feed/ air milk. Can be prevented by not feeding the animals while milking and proper ventilation. Weed such as onion and garlic.
Factors affecting follicle development
Adverse prenatal environment early postnatal environment
What is hydrolytic rancidity? Causes? Development? Prevention?
Also know as Lipolyzed, rancid. The flavor is bitter, or soapy. It is caused by enzymatic hydrolysis of triglycerides and the lipase enzyme liberates free fatty acids. Agitation, alternate heating and cooling, and excessive foaming activates the lipase enzyme. Can be prevented by proper handling and storage.
Grade systems
American systems(blood) Spinning count- hanks of yarn per pound of clean wool Micron Diameter based on actual fiber measurement; most accurate Length- longer are better noilage =very short fibers Color-white is preferred
The Chalazae?
Anchors yolk w/the rest of the albumin layers. Stabilizes position of yolk. and extends into the firm(dense) albumin
Secondary follicles
Associated with primary follicles, mainly emerged btw 1 and 3 weeks of age, incomplete set of accessory structures
Butter
At least 80% fat
what vitamins are water soluble in milk?
B complex, and C and are stable in composition.
Bacteria are normally present in milk. Why?
Bacteria is present in milk because it passes through the cow and is stored in the utters until the cow is milk and it leaves the utters.
Grade
Based on fiber diameter
Red meat
Beef, pork,veal,lamb/mutton, horse
Which milk product requires the largest amount of milk to manufacture?
Butter with 21.2lbs of milk
Minerals
Ca,Cl, Fe, Mg, S, K, P, Na Ca,Mg,P are mostly found in the shell
Caseins
Caseins are only found in milk and are 82% of total milk protein. Contained in micelles. Used when making cheese
List the conditions needed to maintain egg quality during storage.
Clean eggs clean and sanitary facility low temperature(45-55 degrees) high humidity (>80%
What are cultured dairy products? Name two.
Cultured dairy products are milk products that have been fortified with adding beneficial microbes such as yogurt and cultured buttermilk.
Acquired impurities
Dust, dirt, sand, manure, urine
Which has a higher percent protein, milk or eggs? Which has more fat?
Eggs have more proteins then milk. Milk has more fat and saturated fatty acids. Where as sterol is higher in eggs.
Connective tissue network
Endomysium- thin layer that surrounds each cell Perimysium- wrap around several muscle cells and form a bundle Epimysium- surrounds the entire muscle
Describe rennin curd formation and name a product made from it.
Enzyme also known as rennin or pepsin. Binds with Ca+ ions and caseins clot to form calcium paracaseinate. The paracaseinate contains casein, calcium, water, vitamins and enzymes. The sweet whey contains water, lactose, other minerals, albumins and globulins and vitamins. It forms a hard elastic curd, like cheese
Milk is deficient in several minerals which are these?
Fe, Si, Fl, Zn, Cu and trace amounts depend on diet such as Mn, Al, I
Fiber selection criteria
Fleece weight, fineness of hair, length of fibers
What are several internal factors that can influence egg quality?
Genetics, physiology, nutrition
What is the general structure of an amino acid and How does it differ from the structure of a fatty acid?
H O I II R- C -C- OH I NH2 it differs from a fatty acid because it contains a nitrogen.
HTST
High temp- short time 161 degrees for 15 sec
Describe reasons that person may be lactose or milk intolerant.
If a person is lactose intolerant they lack the lactose enzyme. Where as milk allergies are reactions to specific milk proteins
What minerals are found in large quantities in milk?
In large quantities you have Ca, K, Na, S, P, Mg, Cl. Phosphorus is the most mineral in milk.
Attributes used in assigning a quality grade
Interior factors: -Condition of yolk -condition of and thickness of albumen -size of air cell -abnormalities Exterior factors: -shell soundness -shell cleanliness -shape
Primary Constituent in fibers
Keratin(a protein), building block of wool fiber. The chemical composition is sulfur, containing amino acids. Arrangement are long flexible polypeptides and the sulfide bonds hold chains together. they are helical structure
Which disaccharides is found only in milk?
Lactose is a unique carbohydrate that contributes 30% of calories in whole milk. Its composed of glucose and galatose. It in a true molecular solution and has a lower solubility and less sweet than sucrose.
LTLT Pasteurization
Low temp- Long time batch pasteurization 145 degrees for 30 mins
Why is milk homogenized?
Milk is homogenized so the fat doesn't separate in the milk fluid. It is done by pumping the milk through a series of screens under pressure to change the nature and size of fat globules.
Why are facilities and equipment used in the production and handling of milk held to rigid sanitary standards?
Milk is single source of dietary elements needed for the maintenance of proper health, especially in children and older citizens. Milk has a potential to serve as a vehicle of disease transmission and has, in the past, been associated with disease outbreaks of major proportions.
What is the general structure of a fatty acid?
O II R - C - OH
What is oxidative rancidity? Causes? Development? Prevention?
Oxidative rancidity or light induced give off a papery or cardboardy flavor. Oxidation of unsaturated fatty acids copper and iron cataylsts as well as UV light also causes chemical changes. Can be prevented by stainless steal equipment, proper packagaing and storage condition
What are phospholipids? What is unique about these molecules?
Phospholipids are good emulsifying agents because a portion of the molecule is soluble in water and the other portion is soluble in fats. An example would be Lecithin
Natural Impurities
Produced my sheep, grease wool
Adenosine triphosphate
Relaxtion- keep actin and myosin relaxed contraction- provide energy
What is the difference between a saturated and an unsaturated fatty acid? Which type predominates in milk?
Saturated fatty acids will not have a carbon/carbon double bond in the carbon chain where as an unsaturated fatty acid does contain a carbon/carbon double bond. Saturated fatty acid predominate milk with 66%.
Percent of total egg
Shell, shell membranes- 11% yolk- 31% albumen-58%
Describe the structural arrangement of an avian egg beginning with the cuticle and ending with the yolk.
Shell: Cuticle, spongy layer, mammillary layer, membrane: air cell, outer shell membrane, inner shell membrane, albumen: outer thin, firm(dense), inner thin, chalaziterous, chalazae, yolk: germinal disc(blastoderm), latabra, light yolk layer, dark yolk layer, yolk membrane
What is the difference between shrinkage and liquefaction?
Shrinkage is the loss of water Liquefaction is when the albumen becomes runny.
Yield
Shrinkage- loss of weight due to impurities
What is the difference in composition between skim milk and low fat milk?
Skim milk is fat free and has less than .5% fat. Low fat milk contains less than or equal to 1% fat.
High quality egg vs Low quality egg
Small air cell faintly or not visible yolk firm albumen absent blood spot shell soundness
What genetic and environmental factors can cause variation in the composition of milk?
Some factors are feed, proper ventalation and packaging. Also feeding the cow while milking can change the compositon.
What is the difference between acid whey and sweet whey?
Sweet whey is made during the making of rennet types of hard cheese like cheddar or Swiss cheese. Acid whey is a by-product produced during the making of acid types of dairy products such as cottage cheese or strained yogurt.
What are several external factors that can influence egg quality?
Temperature(yolk flattens), Humidity(transfer of gases), Contamination
Describe the visual characteristics of a blastodisk and of a blastoderm. which would you find in a fertilized egg?
The blastodisk is white, circular, opaque(3-4mm), found in an unfertile egg. The Blastoderm is oval transparent center, opaque margins where eggs begin to develop.
What is the function and composition of the albumen?
The function of the albumin is insulation- the volume of protein that doesn't change in temp mostly. Shock absorption- help yolk remain stable in egg and prevent yolk breakage. Nutrient source-high in protein
Wool and Mohair
The hair from a sheep Fleece- of angora goat Australia-wool US- mohair(texas)
What are the major constituents contained in milk. Which are higher in colostrum?
The major constituents are water, fat
The shell of an egg performs what functions?
The shell structure is composed of the cuticle layer, spongy layer, mammillary layer. It permits gaseous exchange, prevent the loss of egg contents and entrance of bacteria, and a nutrition source
What determines shell strength?
The thickness correlated w/weight of bird
What two general types of proteins are present in milk?
To general types of proteins are caseins and whey proteins.
Milk lipids are composed primarily of triglycerides. What are triglycerides?
Triglycerides are a major lipid in fat. they are composed of three fatty acids and a glycerol.
UHT
Ultra high temp 280 degrees for 2 seconds
Why is vitamin D added to milk?
Vitamin D is added to milk to help with preventing osteoporosis.
Medulla
absent in fine wool, hollow
Proteins
account for 22% of calories in whole milk and 38% of SNF. They exist in colloidal dispersion like sand in water. Composed of amino acids.
Whey Protein
also known as serum proteins such as Lactalbumin and Lactoglobulin. They are about 18% of total milk protein
Clip
amount of wool from a sheep when shorn
Ice cream
at least 10% fat
Biologically why is milk important?
biologically milk is important because female mammals provide nourishment to their youngs
How can blood spots be detected in a shell egg?
by the use of candling
Negative wool cloth
can shrink, make people itch
Woolen and worsted
capture air/moisture; sweaters better insulation long fibers arrange in a parallel way; suits
Poultry
chicken, turkey, duck
Diameter or fineness of fiber
consumer prefer secondary fibers(finer)
Felt
created by heating cuticle and matting together
Air cell
forms at the blunt of the egg/store blunt end up. As egg cools, liquids contract its function is to supply air to embryo when respiration is initated
Yolk
functions has nutrients, Blastodisk, and blastoderm, vitelline membrane
Carbohydrates
glycogen (before rigor) lactic acid (rigor)
cream
half and half- milk and cream mixture btw 10.5%-18% fat Light cream- btw 18-30% fat Light whipping cream- Btw 30-36% fat Heavy cream- >36% fat
Describe acid curd formation and name a product made from it.
isoelectric point equals the number of + and - charges and as they combine and caseins precipitate out at a pH of 4.67. Forming a soft curd. like cottage cheese
Why does cream rise to the top?
its due to specific gravity
kemp
large fibers w/o a solid core(hollow). A lot of breakage.
imitation products/ substitute products
look like and taste like but are nutritionally inferior products. Often contain water, corn syrup, and vegetable fats
Shrinkage
loss of water when stored in low humidity air cell enlarges
Sherbet/frozen yogurt
low in fat and solids, but more sugar than ice cream
Grade B milk
mainly for products such as cheese, yogurt, and butter- Class 2
Actomyosin
major protein in meat, myosin makes up the most
What is milk ash?
milk ash are the minerals in milk. They exist in a true solution and as parts of salts and other minerals.
Why is milk pasteurized
milk is pasteurized to kill pathogenic bacteria in milk.
Eggnog
milk products, eggs, and sweetner at least 6% fat
Color and texture of meat
more myoglobin- dark color; used muscles unused muscle- light color- less myoglobin color is affected by pH of muscle
Ruminant lipids
more uniform cow fatty acids 46% unsaturated and 54% saturated
Double yolk
most common defect, two yolks meet in oviduct and are included in same shell
Muscle cell
myofibers- structural units of muscle sarcolemma- excitable outer cell membrane nuclei Myofibrils- long fibers of contractile filaments in myofibers Sarcoplasm- liquid portion of cell
Factors that affect the amount of wool produced
nutrition- sheep need adequate protein and energy for wool production Breeding program- yelld has genetic component
Cheese
over 400 varieties microorganisms provide desired products
Myofibrils
permit each cell to do work a) actin- thin layer filaments; light bands b) myosin- thick filament; dark bands
Germicidal properties
physical properties help kill/ prevent growth of bacteria -shell is the first line of defense, calcium carbonate is a drying agent - shell membranes act as a filter(pores are smaller than those in shell) - Avidin is in the albumen and interferes with bacterial growth -Lysozyme is also in the albumen and dissolves bacteria.
Meat proteins
ranks 3rd nutrition value of protein in different species is about the same Cut of meat has little influence on nutritional protein value.
Monogastric lipids
reflect diet pig fatty acids 54% unsaturated and 46% saturated
Sliding filament theory
regulated by Ca+ concentration calcium held in sarcoplasmic reticulum surrounding myofibrils
Atricial Birds
requiring large amounts of parental care after hatching. tend to have eggs w/less yolk and higher albumen contents.
Precocial bird
requiring little parental care after hatching: able to function independtly
Evaporated milk
sealed and further heat treated doesn't require refrigeration.
fortified milk
skim milk and lowfat milk solids added back to bring SNF up to 10.25%. Also improves flavor
Sarcomere
smallest functional contractile unit. Contains several 100 fliaments
Primary muscle types
smooth-walls of digestive tract, capillaries,etc involuntary striated(cardiac)- heart voluntary striated(skeletal)- muscles have alternating dark and white bands
Applied impurities
sprays, dips, and dyes
Standardization
stabilizes composition of commercially available milk by adding additional milk to achieve desired fat content
Rigor mortis
stiffening of the carcass by intense shortening of muscle fibers
What represents the largest portion of the egg?
the egg white
Shell membranes
tough mats of protein fibers help give structure to egg and membranes separate at blunt end, air cell forms
Myoglobin
transports O2 and CO2 w/in muscle tissue
Latebra
tube like structure and layers of nutrients deposit on the outside
Scouring impurities
use of soapy solution to remove natural and applied impurities
Carbonizing
uses acid to remove organic matter(particles containing carbon)
Ice Milk
usually has more sugar but less total solids than ice cream(fat and protein)
Blood spot
vessel rupture in yolk follicle at time of ovulation and leaves spot on surface of yolk
What are the minor constituents in milk?
vitamins, enzymes, somatic cells, and leucocytes.
Positive wool cloth
warm, non-flammable, can absorb moisture, excellent insulator
Juiciness
wetness produced by release of meat fluids, then sustained moisture by saliva stimulation 2nd tenderness in importance as a palatability factor
Does egg quality affect its nutritional value?
yes it does.