FOS3026 Exam 2
how much milk per day provides substantial portions of DRI
3 cups milk/day
sarcomeres contain two major proteins
actin and myosin
sun-drying
sun provides heat to evaporate water (EX: tomatoes) -challenge: it collects dust sun maid raisins: sand in raisins, sun drying always going to be dust and particles
tenderness ___ as animal ages
tenderness decreases as animal ages
basting
the chicken or turkey periodically in its own juices so it enhances moistness. prevents skin and meat from drying. duck and geese are so high in fat that they do not require basting
drying =
the removal of water
pasteurization goal
to obtain a product that is hygienic that still retains desirable sensory properties
-if pH too high = if pH too low =
too high = microbial growth too low = too much water loss
as an animal ages, more covalent cross-links are formed within collagen helixes which leads to ___
toughening
food preservation methods: #1 thing to control is:
water
physical food spoilage changes due to ____ migration
water
separation
water and oil separation -do not result in formation of new compounds
cell-rupturing
water expands upon freezing; large crystals can rupture food cell walls causing inferior texture
Meats are composed of
water, muscle tissue, connective tissue, adipose tissue, and sometimes bone
two major types of cuts of meat:
wholesale and retail
trussed
wings and legs are tied against the body to prevent from overcooking before the breast is done
fermented milk products
yogurt and kefir
steers
young castrated males
proteolysis
- a type of protease -undesired liquified mass -fish have more active proteases than meat EX: lobster
sweetened condensed milk
-50% of water from whole milk is evaporated, then sugar is added (40-50% of the end product weight) -ideal for preparation of desserts (pie and cheesecake)
cured meats
-EX: ham, bacon, sausage, lunch meats -nitrites or nitrates, salt, sweeteners -preserve meat and adds flavor -dry curing: rubbing ingredients into meat surface -bringing: soaking in salt solution
Rigor mortis
-Latin for stiffness of death, refers to the stiffness that occurs after 24 hours of slaughtering. death stops blood flow and no oxygen is sent to cells. the cells enter anaerobic glycolysis as last resort to make ATP. the pH is decreased, there is no more ATP, and the actin and myosin cannot dissociate
Vertebrate VS Invertebrate Fish
-Vertebrate: fish: have fins and internal skeleton get oxygen from water through gills sea mammals get oxygen from air above water -Invertebrate: shellfish: have external skeletons crustaceans: shrimp, crab mollusks: bivalve, univalve, cephalopod (clam, conch, squid)
Grading of poultry
-Voluntary -three grades, A, B, C -Grade A is the best -Criteria: shape of carcass, amount of meat on bird, amount and distribution of fat, freedom from blemishes -they cut the end off of their beaks, so when they get in fights, the birds don't leave marks
Fish can be purchased:
-Whole fish: body entirely intact -Drawn fish: entrails (inner organs) removed -Dressed: entrails, head, tail, fins, and scales removed -Steaks: cut slicing top to bottom -Fillets: cut by slicing lengthwise front to back -Fish sticks: uniform portions from filet/steaks or minced fish that have been shaped and breaded
coagulation and precipitation: acid
-adding acid to milk causes casein proteins to coagulate -normally, casein carry a negative charge and repeal each other in free solution -acid will donate hydrogen ions to the negative charges of casein and make them neutral -without charge repulsions, they coagulate
coagulation and precipitation: heat
-at higher temp, whey proteins start to denature -denatured whey loses solubility and coagulated with casein -skin forms at surface of heated milk due to evaporation of water and concentration of milk components -skin scorches easily and can trap steam trying to escape causing milk to boil over
biological: yeasts
-attracted to liquid foods in high sugar -fruit, preserves -can cause unwanted fermentation -can control by keeping water activity low alcohol, anywhere there is sugar, yeast will grow
how is histamine formed in fish?
-bacteria is responsible for making it -if you don't freeze your fish, histamine is a risk factor
Classification of poultry
-broilers/fryers: slaughtered at young age -roasters: older and larger than broilers/fryers
Lean VS Fatty Fish
-can identify by relative fat content -fish are not fatty to begin with -Lean: very low (<2.5% by weight) low fat: (<5% by weight) -Fatty: moderate (<10% by weight) higher fat: (<10 g)
selection of shellfish
-can purchase live (lobster, oysters, clams, ) or processed -highly perishable, to maintain quality are usually kept alive until last minute -to check if alive, tap shells - should lose tighter
coagulation and precipitation: enzymes
-cause milk coagulation via casein hydrolysis -most common enzyme used to coagulate milk: chymosin, sold commercially as rennet -enzyme-produced coagulates have a tough, rubbery texture -acid-produced coagulates are more fragile
cream
-collection of fat droplets that float to the top of non-homogenized milk 18-36% milk fat -whipping cream is 30-36% -expands 2-3 times in volume -proteins are mechanically stretched into thin layers that trap air, fat and liquid -higher fat content leads to more stable whipped cream
dried meats
-cooked, sometimes smoked and dried under specific temp and humidity -jerkies
storage of poultry
-dark meat cannot be stored as long as white -dark meat is higher in myoglobin and fat -iron in myoglobin acts as metal catalyst to speed up lipid oxidation -refrigerated -frozen
DFD Meat
-dark, firm and dry meat -results from exhaustion and thus depletion of glycogen before slaughter -high pH values, meat has enhanced capacity to hold water which gives dry and sticky texture
The decrease in pH from lactic acid accumulation influences meat quality by:
-decreased microbial growth but can also lead to water loss -water holding capacity decreases as proteins become neutral
canned meats
-either pasteurized (require refrigeration) or sterilized (does not require refrigeration if sealed)
searing
-exposing meat to very high initial temp -intended to seal outside to keep juices in and increase flavor and color -not actually effective in juice retention but valuable technique for improving flavor and color through caramelization and Malliard Rxn
artificial tenderizing
-external treatments -enzymes: commercially available -papain: papayas -Bromelin: pineapples -Ficin: figs -Trypsin: pancreases of animals Salts: increase water retention acidic marinades: break down outside surface of meats mechanical tenderization: grinding and pounding physically breaks down muscle cells and CT
Composition of Fish and Shellfish
-fish are tender, due to: 1. Low collagen 2. Less of the amino acid hydroxyproline 3. Muscle Structure
what role does muscle structure play in fish tenderness?
-fish have short muscles (unlike the long bundles of fibers in mammals and birds) -arranged into myotomes: layers of short fibers -myotoms are separated by myocommata: large sheets of thin connective tissue -cooking gelatinizes CT so muscle tissue is readily disintegrated into flaky segments
lemon juice and fish odor
-fishy smell comes from trimethylamine - component attached to certain phospholipids -bacteria and enzymes that contribute to deterioration split the trimethylamine from phospholipid and release it into a form that has a fishy odor -acids (lemon juice) added to cooked fish convert odorous liquid trimethylamine form into an odorless solid
irradiation (cold pasteurization)
-food is exposed to ionizing energy source (gamma rays, X-rays, electrons) -food does not become radioactive -super effective but least accessibility effective in killing stubborn bacteria -highly controversial -free radicals damage DNA of microorganisms -used in wheat flour, potatoes, spices, meat, eggs -concern over possible nutrient loss, environment hazards and free-radical production -labeling requirements "treated with radiation)
pasteurization
-foods are heated to specified temp for a certain period of time to destroy microorganisms (milk 145 for 30 min) high-temp short time HTST: 161 F for 15 sec ultra high temp UHT: >280 F for 2 sec UHT milk tastes burnt, sugar gets charred
storage of fish and shellfish
-fresh finfish should be eaten within 1-2 days -store in coldest part of fridge -wrap well -eat fresh shellfish the day of purchase -can be kept alive in cool, wet environment in fridge -freezing greatly extends storage time -lean fish keep logger than fatty fish -fat is major problem in preservation of fish -unopened cans of fish are shelf stable for up to 1 yr
flavored milk
-fruit, vanilla, chocolate -chocolate milk: stabilizers prevent cocoa from settling -common stabilizer: carrageenan (polysaccharide from seaweed)
turkey types
-fryer-roaster: very young and small in size, seldom sold on market -young hen (female) / young tom (male): larger than fryer/roaster, more often sold
hormones
-given to encourage rapid weight gain -reduces production cost -concerns over safety of residues in human health and environment -organic beef is raised without antibiotics or hormones
antibiotics
-given to ensure health and promote growth -may contribute to development of antibiotic-resistant bacteria
fish undergo rigor mortis
-have less glycogen so pH remains high -high probability of microbial infection -spread of skin microflora after death cause rapid decay -histidine is predominant free amino acid in fish -during decay, large amount of histamine can form
pasteurization of milk
-high temperature (below BP) short time -inactivates many enzymes that cause off-flavor -destroys close to 100% of pathogenic microorganisms and 95-99% of nonpathogenic bacteria -those 1-5% of remaining bacteria can convert lactose to lactic acid and cause spoilage
variety meats
-highly valued sources for micronutrients and protein -organ meats: kidney, liver, usually extremely tender -muscle meats: tongue, heart: usually very tough
challenges to canning
-home canning, not done properly -don't want to use high temperature because it will affect the texture, use mild temperature with using more salt and canned products in industry has too much sodium EX: soups
what role does hydroxyproline play in fish tenderness?
-hydroxyproline is partly responsible for collagen's triple helix structure -less hydroxyproline allows collagen to breakdown easily at lower temps and convert to gelatin
styles of poultry
-live: rarely purchased by consumers -dressed: only blood, feathers and craw removed -Ready-to-cook: free of blood, feathers, craw/crop, heat, feet, and entrails -convenience: poultry has been cut into smaller pieces (halves, breasts, wings, thighs )
instant milk
-made by exposing NFDM to steam and then re-drying it -double drying makes it instantly dissolve in cold water due to agglomeration of smaller proteins into larger more porous proteins
yogurt
-made by mixing two thermophilic bacterial strains -lactobacillus bulgaricus + streptococcus thermophiles -mixture of bacteria added to pasteurized milk with some additional MSNF -whole mixture held at warm temp to allow fermentation until desired consistency and flavor reached -lactose turns to lactic acid -folate is produced as byproduct of bacterial growth
Inspection of poultry: 1968 Wholesome Poultry Product Act
-made inspection of poultry shipped across state lines mandatory -USDA inspects for wholesomeness and sanitation -before and after slaughtering and at processing plant -stamped with USDA inspection mark if passes
tenderness and juiciness
-maximized by cooking at the right temp/time combo -high temp for too long will toughen and shrink meat ue to protein denaturation and water loss -softening of connective tissue happens at same temps that cause toughening of muscle proteins: -time/temp depends on amount of collagen present in the cut -low and slow moist heat best for tougher cuts - collagen degraded and converted to gelatin -dry heat methods best for tender cuts
purchasing poultry: antibiotics
-may be given to prevent disease -withdrawal period prevents residues left in food -chickens have quadrupled in size in the last 50 years
smoking cured meats
-meats exposed to smoke of burning wood for added flavor -salt makes moisture less available -sugar will be fermented by meat, lowers pH, less chance of pathogens -lactic acid reduces pH, pathogen will not grow -meat products: nitrates keep color, if you don't add nitrates then the red will not be present
storage of meats
-meats have high amounts of protein and water -stored in fridge or freezer -can be stored in original wrap for up to 2 days -raw meat should be cooked or frozen by "use by " date -cooked ground meat can be stored up to 2 days, cooked whole cuts for 3-5 days
fermentation
-microorganisms convert sugar to alcohol, gases and acids -most spoilage microorganisms cannot survive in acidic or alcoholic environment
functions of milk in foods
-milk by itself as a beverage -several drinks use milk as their base -several foods are derived from milk -food industry uses specific components of milk as ingredients in processes foods -purpose of this is to improve protein content, moisture, emulsification, texture, color and flavor
eggnog
-mixture of milk, cream, milk solid, eggs, stabilizers and spice -6-8% milk fat (double that of whole milk)
connective tissue
-mixture of proteins and polysaccharides that act as glue and holds muscle cells togther
Collagen
-most abundant protein -tough and fibrous but softens upon heating -unique triple helix structure held together by hydrogen bonds and covalent cross-links
White VS Dark Meat
-muscles that are used more frequently have more myoglobin (require more oxygen) -thighs and drumsticks are dark meat because they are the muscles that move the most -do almost no flying so breast muscle has less myoglobin and whiter color -wild birds, like ducks, have darker breast meat because they use the muscles for flying
muscle contraction
-nerve impulse initiates contraction -calcium ions released into sarcoplasm -exposes active site on actin -actin then reacts with myosin to form actomyosin cross-links -myosin pulls actin towards center and sarcomere shortens
additives in processed meats
-nitrites: keep processes meats' pink color -safety becomes concern after discovery that carcinogenic nitrosamines can form in stomach -levels in food lowered, but not eliminated -preservatives: antioxidants BHT, BHA -favorings: salt, sugar -Coloring agents: annatto, saffron, turmeric
dry milk
-nonfat dried milk NFDM: all moisture is removed from milk -reconstituted with water and used like fresh -absence of fat gives even longer shelf life
preparation of poultry
-not recommended to wash prior to prep -thaw frozen poultry in refrigerator in a pan -prepare and cook stuffing separately
smoked meats
-placed in smoker and exposed to smoke of burning wood -most cured meats are also smoked -late 1800s technique developed to distill smoke into a liquid = liquid smoke -can be spread on cured meat to achieve smoke flavor
milk fat
-plays major role in flavor of milk and mouthfeel (EX: creamy chocolate milk) -consists of triglycerides surrounded by protein and phospholipid membrane -membrane allows for colloidal dispersion of fat in aqueous phase
pickling
-preserves through acidification (acidity controls microbial growth) -vinegar often used (acetic acid)
carbohydrates
-primarily lactose -lactose can be fermented by bacteria into lactic acid -adds flavor to cheeses and fermented milk products -tartness of yogurt
composition of milk
-primarily water 87% -remaining 13% Is fat and milk solids-nonfat MSFN: carbs, protein and micronutrients
Top: 1. Prime, 2. Choice, 3. Select
-prime: primarily sold to restaurants, most marbling, most expensive -choice and select: most common purchased by consumers in grocery store 4. Standard and 5. Commercial: usually not sold at retail level bc they are from older cattle 6. Utility 7. Cutter and 8. Canner: used for processed foods
ultra pasteurization
-process of heating raw milk for two to hour seconds at 275 to 300 F, then aseptically packaging it to stay fresh for 60 to 90 days -product kept under refrigeration -after opening it will hold only as long as any other milk -doing this makes milk taste burnt
ceviche
-raw fish prepared with acidic marinade -lemon or lime juice -acid denatures proteins and turns flesh white -muscle tissue is tenderized without heat -concerns with raw fish: CDC warns that consumption of raw seafood can contain biological food hazards
moist heat preparations
-recommended for older, tougher birds -braising, stewing, poaching
raw fish
-sashimi: raw fish consumed alone -sushi: rice product served with sashimi, cooked fish, spices -nigari: pressed rice with something on top -maki: rice and fish rolled into seaweed -uramaki: similar to maki but fish and vegetables are on inside of nori and rice on outside
kefir
-sour, carbonated, slightly alcoholic beverage -made by adding a yeast/bacterial fermentation starter to fluid milk
kobe beef
-special grade beef from Waygu cattle, massed with sake and fed diet of beer
biological: bacteria
-susceptible foods: high water activity, high protein -can control by keeping water activity low -high moisture and protein
cold preservation: freezing
-the least damaging preservation method in terms of flavor, nutrient content, and texture -makes water unavailable to microorganisms -still some oxygen present
myosin
-thick filament of protein found in muscles
actin
-thin filament of protein found in muscles -contains tropomyosin and troponin -tropomyosin: stabilizes actin structure -troponin: contains Ca-binding protein
canning benefits
-through heating and removal of oxygen, canning destroys and prevents growth of microorganisms -keep pH below 4.6
biological: molds
-under suitable conditions of moisture, air and temp, will grow on any food -can control by keeping oxygen levels low -vacuum -like dry stuff, not favorable for bacteria
polyphenol oxidase
-undesirable browning of fruits and vegetables -fruit, vegetable, anywhere you see browning -malliard reaction is enzymatic, this is not -needs oxygen
processed poultry
-used in canned or dried soups, frozen dinners, pot pies, sausages, hot dogs, burger, etc. -chicken nuggets: either whole chicken pieces or paste of minced chicken meat and skin -high in kcal due to deep frying -pink slime = lean finely textured beef
bones
-used to identify meat cuts
determining doneness of chicken
-using thermometer to check internal temp is the best way -min of 165 F, if stuffing, the stuffing also needs to reach 165 F the remaining methods can be used when it is time to use the meat thermometer: -color change -touch -time/weight charts
meat grading
-voluntary -USDA contracted by meat packer or distributor -Quality grade -color, grain, surface texture, even fat distribution
grading of fish is ___
-voluntary -paid for by processor -only fish that are inspected can be graded -based on appearance, texture, uniformity, flavor, odor, absence of defect -Grades: A,B, and substandard
inspection of fish is ___
-voluntary -paid for by processor -responsibility of National Marine Fisheries Service of US Dept. of Commerce -Based on wholesomeness and sanitary conditions
grading of milk
-voluntary, paid for by dairy industry -milk is graded according to sight, odor, bacterial count and presence of contaminants (antibiotics)
composition of poultry
-water and muscle -have higher ratio of myofibrils to sarcoplasm -contracts rapidly but tires quickly -connective tissue, adipose tissue, and bone
evaporation
-water loss due to improper storage -undesirable dried out appearance
carving
-way meat is sliced affected tenderness -grain: direction in which muscle fibers are running -cutting across the grain increases tenderness by shortening muscle fibers into smaller, easier to chew segments
muscle relaxation
-when nerve impulse stops, calcium is pumped out of sarcoplasm -actomyosin cross-links break -sarcomeres return to original length
two proteins in milk are
1. Caseins: primary milk proteins 80% of total. precipitate when treated with acid or enzymes 2. Whey: about 18% total milk proteins. liquid portion of milk that separates from the curd during cheese production. can isolate whey proteins - used extensively by food industry
four problems with frozen foods:
1. freezer burn 2. cell-rupturing 3. fluid loss 4. recrystallization
4 methods of determining doneness
1. meat thermometer 2. time/weight charts 3. color change 4. touch
canning: 2 step processes
1. preparation: packing food and liquid into container. required to ensure vacuum seal. -headspace: small amount of air left on top 2. heating: boiling water processing, needed for low-acid foods
4 types of fresh fluid cows milk
1. whole milk 3.25% milk fat 2. reduced-fat: 2% milk fat 3. low-fat milk: 1% milk fat 4. Fat free or non-fat: <0.5% milk fat
heat preservation: boiling
10 min boiling kills/inactivates most microorganisms
fresh fluid cows milk must contain
4 types, all must contain at least 8.25% MSNF
sarcomeres are bordered by dark bands called
Z-lines
eliminating available water can be done by 2 different methods:
Physical and Chemical
1/4 of US chickens carry: 1/2 of US chickens carry :
Salmonella Campylobacter jejuni
Saltwater VS Freshwater Fish
Saltwater: -majority of fish in US taken from saltwater -herring, cod, tuna, halibut -more distinct flavor Freshwater: - pike, carp, trout, tilapia -some can live in both environments: aka salmon, eels
US Department of Commerce oversees the monthly online publication of the Interstate Certified ___ Shippers List
Shellfish -where was your fish caught, processed, where in world -challenge is there is so much being imported -very hard to track location of fish -only shellfish from ICSSL can be sold commercially -come rom certified waters -containers labelled with harvesting info and certification #
Beef: classified according to sex and age
Steers: male, young, castrated, gain weight fast Bulls: male, older, uncastrated, tougher meat Heifers: female, not yet born a calf, used for meat Cows: females have borne calves, meat less desirable Calves: 3-8 months old, too old veal, too young beef, may be sold as baby beef
purchasing poultry: hormones
USDA does not allow the use of hormones for raising chickens
what vitamins does milk contain
Vitamins A, D, and B2 (riboflavin) Vitamins A and D: -fat soluble, found in milk fat -most milks fortified with A and D -required for fat free milk Vitamin B2: -riboflavin degrades under exposure to UV light -this is why milk is packaged in cardboard or opaque containers -milk contains the amino acid Tryptophan, which, is a precursor to niacin formation
heifers
Young female cows that have never had a calf
cover dat
appears on outside of meat
evaporated milk
at least 60% of water from whole milk is evaporated
biological food spoilage methods
bacteria, yeasts, molds
Dry heat preparation of fish and shellfish
baking, broiling, grilling, frying, sautéing, deep frying
Yield Grade
based on ratio of lean muscle to non-meat portion (fat, bone, inedible material) -scale of 1 (highest yield) to 5 (lowest)
changes that contribute to food spoilage
biological, chemical, physical
protease will act on proteins and then cause food product to start tasing ____
bitter
natural tenderness influence: genetic factors
black Angus beef are bred to be heavily muscled and marbled
adipose tissue
fat serves as insulation and padding for sensitive organs
lipases:
break down lipids (triglycerides) into glycerol and fatty acids
what is the major mineral in milk
calcium
processed fish products
canned, cured, fabricated
freezer burn
caused by moisture loss (via sublimation) resulting in altered texture, appearance and flavor -due to improper packaging or prolonged freezing -product frozen for a while, ice crystals form drilling through tissue and makes holes, quality is decreased
main proteins in CT
collagen, elastin, reticulin
#1 factor influencing consumers when purchasing meat
color
milk is a ___ protein source
complete
fish fat and liver oil are significant sources of ___-soluble vitamins
fat-soluble ADEK
Natural tenderness of meat is influenced by
cut of meat, animal's age, genetic factors, diet, rigor mortis
natural tenderness influence: diet
directly influences animal's fat accumulation
ohmic heating
electrical current passed through food to generate heat to destroy microorganisms -used in juice preservation -meat based product doesn't work in real life, ohmic heating works in liquids like fruit juice
primary aim of food preservation
eliminate microbial spoilage by limiting available water
chemical changes due to ___: proteins that catalyze chemical reactions
enzymes
freezing increases shelf life, ____ still remain active
enzymes
what changes color of meat
exposure to oxygen
Food Preservation Goal
extend shelf life to allow storage and convenient distribution
whiter fish have higher concentration of ___-twitch muscle fibers (needed for quick bursts of speed, less myoglobin)
fast-twitch
pulsed light:
food exposed to intense, brief flashes of light -disrupts bacterial cell membranes, but not those of surrounding foods -damages bacterial DNA -pulsed light emits UV light that sanitizes -challenge: you cannot use it for long time, food becomes too hot, only effective in short times
reticulin
forms interlace around muscle cells for support
fluid loss
frozen meat loses water when thawed, can result in drier texture
freeze-drying
frozen solid water is sublimated (solid to gas) at low pressure and temperature (EX: instant coffee)
highest grade of milk
grade A: most sanitary
elastin
has elastic properties
pigment portion of meat
heme
curing
high concentrations of solutes (salt, nitrates, nitrites, sugars) draw water out of food, making it unavailable to microorganisms
as an animal ages, collagen content _____
increases
color compounds
interfere with light transmission and contribute to opaque, heavy color -contributors to color include: fat, dispersed proteins, riboflavin, amount of fat-soluble yellow pigments (carotenoids) in plants consumed by the cow
marbling
intramuscular fat seen as white streaks -well marbled beef is more expensive -contributes to flavor and juiciness
probiotics
live microbial food ingredients (bacteria) that promote digestive health and wellness
Food Safety News: MDH Investigating E. coli 0157 infection associated with Minnesota State Fair, caused by?
livestock from the petting zoo
tougher cuts from older animals are less expensive and require slow, moist-heating, at ___ temperatures to hydrolyze collagen - gelatin
low temperatures
in freezing, higher fat content = ____ shelf-life due to rancidity
lower
federal meat inspection act 1906
made inspections for all meat transported across state lines or brought into the US mandatory -gauruntees wholesomeness, not quality -USDA's responsibility -examine live animals, slaughtered carcasses and meat at processing facilities -monitor temps, packaging, labeling and hygiene -meat that passes inspection receives a stamp
veal
male or female young calves -3 weeks to 3 months old other calves sold as "yearling beef" -fed milk-based diet and restricted in movement -unique flavor influenced by presence of lactic acid
best way for nutrient retention
maximum is high pressure processing freeze drying because there is no heat
natural tenderness influence: animal's age
meat from older animals is tougher because diameter of muscle fibers increases and more connective tissue develops
mutton
meat from older sheep (>14 months) -darker, tougher, stronger flavor
pork
meat from young wine of either sex -5.5 -7 months old -interspersed with and surrounded by fat 20-40% -about 1/3 sold as fresh pork, the rest is cured into ham or sausage or bacon
lamb
meat from younger sheep (<14 months)
lamb and mutton
meat of sheep
homogenization
mechanical process that breaks up fat globules in milk into smaller globules that do not clump together and are permanently dispersed -no effect on nutrient content -sensory properties change: creamier, whiter -milk pumped under high pressure through machine that contains tiny holes to break up globules
over storage time, meat may be further oxidized and become brownish red
metmyoglobin. (Fe2+ to Fe3+)
Most dangerous limitation to food preservation
microorganisms
USDA Choice
moderate marbling is delicate lacy streaks that is less evenly distributed than in Prime
smaller and more numerous muscle fibrils result in smaller muscle bundles which means the meat is
more delicate and velvety
water soluble vitamins C and B are ____ susceptible to nutrient loss after cooking in liquid
most
natural tenderness influence: cut of meat
muscles that are exercised are more tough (cuts from muscles used for more locomotion) -have higher concentrations of connective tissue
contractile units of muscle
myofibrils
color of meat is primarily from a pigment0containing protein
myoglobin
pigment of fish depends on how much ___ is present
myoglobin
the internal color of meat is purple-red
myoglobin
prebiotics
non-digestible food ingredients (usually fibers) that support the growth of probiotics -essentially food for the probiotics
food spoilage is
obvious and detectable -sensory properties are affected -can pertain to safety or quality or both
depending on their diet, some fish contain astaxanthin: a pigment imparting characteristic ____-_____ color
orange-pink color
as soon as the meat is cut from the carcass and exposed to oxygen, the meat becomes bright red
oxymyoglobin
other abundant minerals in milk
phosphorus, potassium, magnesium, sodium, chloride, sulfur
moist heat preparation of fish and shellfish
poaching, simmering, steaming, clambakes
vacuum drying
pressure is lowered below atmospheric, which lowers boiling point of water (EX: tomato paste) -sucking out air, evaporates faster
wholesale meat
primal cuts: large cuts of animal carcass (7-9 cuts)
if you leave cooked fish all day and leave it til next day, it will be more tender, this is explained by:
proteases
fish has more _____ than meat
proteases. EX: lobster
dry heat preparations
roasting, broiling, grilling, frying
is salting VS acid better?
salting is better than acid -salt will kick out pathogenic bacteria and lactic acid bacteria
each muscle fiber cell is surrounded by an outer membrane called
sarcolemma
fibrils are separated into units called
sarcomeres
each muscle fiber cell is filled with cellular fluid called
sarcoplasm
Meat
skeletal muscles of mammals, may include their organs and glands as well. Technically excluded flesh of non-mammals (poultry and fish)
-darker red flesh of fish from higher concentrations of ____-twitch muscle fibers (needed for endurance and long distance thus having more stores)
slow-twitch
cold preservation: refrigeration
slows down biological, chemical and physical reaction
recrystallization
small ice crystals melt and refreeze as larger crystals affecting texture -occurs with temp fluctuations -ice cream, if you eat a little, leave for a long time, it will melt then freeze again -during that time, small water crystals come together and form larger crystals, there will be recrystallization, biggest defect in ice cream
retail meat
smaller cuts of meat derived from wholesale cuts sold to consumers
bone marrow
soft, fatty material in the center of bones -valued food in many cultures -can provide flavor to soup
proteases:
split proteins into smaller peptide and polypeptide fragments
USDA Select
spotty marbling scattered like rice grains
milk contains the amino acid ____ which is a precursor to vitamin B3, niacin, formation
tryptophan
micronutrients and fat-soluble vitamins and minerals are relatively ____ by processing
unaffected
osmotic drying
uses concentrated syrup to osmotically draw out water (EX: raisins) -osmotic is salting out -making kimchi, put salt in cabbage -pickels: making water unavailable
conventional drying
uses heat to evaporate water -tray, tunnel, drum, spray drying (EX: whey)
high pressure processing HPP
uses high pressure <50,000 psi for 15 min to deactivate microorganisms and enzymes responsible for deterioration -used in juices, sauces, ready to eat meals -HPP putting food product in vacuum pack, in water, applying lots of pressure -high pressure inactivates enzymes and bacteria, does not use heat so flavor is unchanged
classification of fish and shellfish
vertebrate, invertebrate, saltwater, fresh water, lean, fatty can overlap between schemes: a fish can be both saltwater and vertebrate
USDA Prime
very heavy marbling that looks like snowflakes and is evenly distributed