Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

FOOD2000 > FOOD2000 END OF SEM > Flashcards

FOOD2000 END OF SEM Flashcards

1
Q

What is the general composition of meat?

A
  • 70% water

  • 21% protein

  • 8% fat

  • minerals (ash)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does the quality of meat depend on?

A
  • breed
  • heredity
  • sex
  • feeding
  • pre-slaughter & slaughtering conditions
  • dressing
  • carcass cooling
  • storage conditions 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the purpose of meat grading?

A

Establishes & maintains uniform trading standards & aids in determination of value of various meat cuts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is used to determine the class and grading of meat?

A

Dentition (number of teeth), weight & fat depth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the steps in slaughtering?

A
  1. Stunning: renders animal unconscious, prevents pain/distress
  2. Sticking: severs major blood vessels in neck or thorax
and animal bleeds to death (exsanguination)
  3. Skinning/Dehairing & Evisceration: minimises microbial contamination
  4. Inspection: done ASAP after slaughter to identify abnormalities or disease
  5. Washing & grading: fine spray of water to remove surface blood & bone dust, sometimes done using hot (water or by including low concentrations of organic acids)
  6. Refrigeration: done after being bled, skinned & eviscerated (removal of internal organs). Carcases are chilled for 24-48h before grading & processing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens after slaughtering?

A

Chilling and aging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does chilling cause?

A
  • Muscle contract & stiffen = rigor mortis
  • as rigor mortis begins, meat becomes progressively less tender until rigor mortis completed
  • Chilling done immediately after slaughter to prevent spoilage.
  • Cold shortening = occurs when muscle chilled to <16°C before rigor mortis completion (meat becomes tough). Same result if carcase frozen before rigor mortis completion “thaw rigor”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does meat aging cause?

A
  • Holding meat in refrigerator
  • Increased tenderness due to natural enzymatic changes taking place in muscle.
  • Beef held at higher temperatures tenderises faster BUT may also spoil
  • Pork & lamb rarely aged = as already tender as relatively young
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are Livestock marketing & prices affected by?

A

weather, feed prices, government import policies & consumer demands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is meat curing?

A
  • preservative method
  • flavour & colour enhancement

Some curing agents:
- Salt = preserve & add flavour.
- Sodium nitrate & sodium nitrite = fix red colour of meat, acts as a preservative & prevent microbial contamination
- Sugar = colour stability & flavour
- Spices = produce desired flavour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is meat smoking?

A
  • Smoke protects fat from rancidity

  • Contributes to colour characteristics

  • Creates unique flavours in processed meats
  • Smoke most effective microbial growth inhibitor when used with other preservation techniques
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does meat colour indicate?

A
  • Myoglobin = protein that is the primary colour pigment of meat (store oxygen in muscle tissue)
  • Exposed to air/heat, goes from red to brown
    • Oxygen present = meat is bright red colour
    • Oxygen absent = meat is purplish in colour 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the Factors affecting milk composition?

A
  • Nutritional factors: Type of feed and Quality of feed
  • Non-nutritional factors:
  • Breed
  • Stage of lactation
  • season & temperature
  • Age & size
  • Disease
  • Milking frequency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the by-products of milk?

A
  • Concentrated & dried products
  • Whey products
  • Yoghurt
  • Cheese
  • Butter
  • Ice cream
  • Other fermented products
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is yogurt?

A
  • A semisolid fermented milk product
  • Flavour varies but basic ingredients & manufacturing essentially consistent
  • uses milk from cows
  • Whole milk, partially skimmed milk or cream (GREEK) used
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the cooking function of eggs?

A
  • Bind ingredients
  • Leavening agent
  • Thickening agent
  • Emulsify mayonnaise, hollandaise sauce
  • Glaze on breads & cookies
  • Clarify soups & coffee
  • In boiled candies & frostings = retard crystallisation
  • Hard cooked & used as garnish
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the codes on eggs?

A
  • After cleaned & checked for quality, every egg is stamped with unique code that identifies farm where it was laid = allows eggs to be traced back to farm of origin if necessary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the composition of the egg yolk?

A
  • Up to 35% liquid weight of egg
  • Contains all the fat & just less than 1⁄2 the protein
  • Contains higher proportion of egg’s vitamins and minerals
  • Contains all the zinc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the composition of the egg white?

A
  • Contains more than half the egg’s total protein, niacin, riboflavin, and major inorganic compounds like chlorine, magnesium, potassium, sodium & sulphur
  • protein containing all essential AA
  • More opalescent than white
  • More transparent in older eggs than fresher eggs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the steps in egg quality control?

A
  1. Inspection: Eggs inspected by series of machines
  2. Dry Cleaning: using a soft bristled sanitised brush or by gentle rubbing with sanding sponge, cloth or paper towel (visibly dirty eggs segregated away from clean eggs)
  3. Washing: Some farms wash eggs in warm water & gentle sanitiser liquid as soon as collected = washing process is very fast & are dried immediately
  4. Light disinfectant: Many farms run eggs through UV light disinfectant system to kill any bacteria
  5. Internal quality: Bright lights to inspect egg’s internal quality = process called ‘candling’
  6. Candling: If any internal defects noticed, eggs removed & sent separate from first quality eggs
  7. Height and thickness: Tiny cracks not visible to human eye are checked & measuring height of egg white & shell thickness done
  8. Crack detector: Automatic acoustic crack detectors containing lots of small probes gently tap eggs at very fast speeds as they pass through machine = if cracks in eggshell, no matter how small, tapping energy will be absorbed, resulting in duller sound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does the egg structure contain?

A
  • shell
  • white
  • yolk
  • air cell
  • chalaza
  • germinal disc & membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the three main egg farming systems?

A

free range, caged, barn-laid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the Chicken meat processing steps?

A
  1. Inspection; classifying and grading
  2. Suspension and shackling of each bird by legs
  3. Stunned immediately with electric shock
  4. Bleeding
  5. Scalding to loosen feathers
  6. Feathers picked off by machine
  7. Removing of pinfeathers
  8. Evisceration
  9. Chilling in ice water
  10. Postmortem inspection
  11. Grading
  12. Packing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the classification of butter?

A

Usually divided into two main categories:
- Sweet cream butter
- Cultured or sour cream butter made from bacteriologically soured cream (fermented product)


Butter can also be classified according to salt content:
- unsalted

- salted

- extra salted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How are meat carcases sold?

A
  • Sides
  • Quarters
  • Wholesale cuts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

In dried meats, what is the purpose of fermentation?

A

encouragement of lactic acid bacterial growth = useful as meat preservative & tangy flavour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are textured protein products?

A
  • at least 50% protein
  • Contain eight essential AA & vitamins + minerals found in meats
  • Soybean protein most commonly use
  • Other proteins used = wheat gluten, yeast protein = used singly or in combination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the storage of eggs?

A
  • Can be stored in shell at -1°C for up to 6 months
  • Can be frozen out of shell for extended storage
  • Eggs may be frozen as whole egg minus shell, separately as white & yolk
  • For food manufacturing needs = eggs minus shell, can be dehydrated (dried) as whole eggs, whites, yolk using spray drying, tray drying , foam drying & freeze drying 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are blood spots on eggs?

A
  • Occasionally found on egg yolk
  • Don’t indicate a fertilized egg = caused by rupture of blood vessel on yolk surface during egg formation or by similar accident in oviduct wall
    

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the composition of milk?

A
  • primarily of water
  • Carbohydrates
  • Lactose
  • Fat
  • Protein
  • calcium, phosphorus, magnesium, potassium, sodium, chloride & sulphur
  • thiamine & riboflavin
  • Solids-not-fat: lactose, caseins, whey, proteins & minerals

Fluid milk is; A colloidal dispersion of the protein casein & the whey proteins and An emulsion with fat globules suspended in the water phase of milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are meat substitutes?

A

Plant protein products
- Spinning vegetable proteins into fibres
- protein dissolved in alkaline solution then extruded & coagulated to form fibre bundles
- flavour & colour compounds and binders are added such as egg albumen or vegetable gum, emulsifiers
- Fibres then processed into shapes & textures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are Physical properties of milk?

A
  • Opacity = due to suspended particles of fat, proteins and certain minerals
  • Colour = white to slight yellow (carotene content)
  • isotonic
  • pH and Acidity - important indicator of microbial quality of raw milk: pH of fresh milk = 6.6 to 6.8 (0.13% lactic acid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the air cell in an egg?

A
  • The empty space between the white & shell at large end of egg
  • When egg first laid, its warm; contents contract as it cools = inner shell membrane separates from outer shell membrane = air cell formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the chalaza in the egg?

A
  • Ropey strands of egg white that anchor yolk in place in centre of thick white
  • More prominent = fresher the egg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What does the colour of egg shell show?

A

Has nothing to do with egg quality, flavour, nutritive value, cooking characteristics or shell thickness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the effect of milk composition?

A
  • Milk prices based on the milkfat and protein solids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are the steps in cheese production?

A
  • Treatment of milk
  • Additives
  • Inoculation & milk ripening
  • Coagulation; Enzyme, Acid, Heat + acid
  • Curd treatment (visco-elastic gel/coagulum)
  • Cheese ripening
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is cheese?

A
  • fresh or ripened product obtained after coagulation & whey separation of milk, cream or partly skimmed milk, buttermilk, or a mixture of these products
  • Essentially the product of selective concentration of milk = casein, fat & water (10% cheese yield from milk)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is butter?

A
  • Represents about a 20-fold concentration of fat to milk
  • Made by churning pasteurised cream at cool temperatures (< 10°C) 

  • Churning breaks fat globule membrane = emulsion breaks, fat coalesces & water (buttermilk) escapes
  • Contains 80% milkfat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the membranes in the egg?

A
  • Two shell membranes just inside shell; inner & outer; after egg laid = cools & air cell forms between two layers at large end of egg
  • Vitelline membrane; covers yolk and protects from breaking = weakest at germinal disc & gets more fragile as egg ages
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the germinal disc in the egg?

A
  • The channel leading to yolk centre
  • When egg is fertilised, sperm enter by way of germinal disc & travel to centre & embryo chick starts to form
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What does the colour of the egg yolk depend on?

A
  • diet of hen
  • Pigments not changed during cooking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What are the types of emulsion?

A
  • Oil in water emulsion (O/W): Oil droplets dispersed in 
aqueous phase 

  • Water in oil emulsion (W/O): Water droplets dispersed in oil phase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is emulsion?

A
  • a dispersion of one fluid into another
  • Fluids are normally immiscible (dont mix)
  • Substance making up the droplets in emulsion is the discontinuous, dispersed or internal phase
  • Substance making up the surrounding fluid is called the continuous or external phase
  • Emulsifier coats emulsion droplets, preventing them from coalescing or recombining with each other 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are the basic steps of manufacturing ice cream?

A
  • Blending of mix ingredients
  • Pasteurisation
  • Homogenisation
  • Chilling & Aging the mix
  • Freezing
  • Packaging
  • Hardening 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is ice cream made from?

A

basic white mix:
- milk
- cream
- skim- or whole milk powder
- buttermilk powder
- condensed milk
- whey powder
- anhydrous milk fat
- unsalted butter 


How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

In the ice cream process, what is pasteurisation?

A

Usually 80-85°C for ~15-30 sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

In the ice cream process, what is homogenisation?

A

-Essential for good smooth texture & even dispersion of ingredients
- Usually at ~75°C
- Reduces size of fat globules
- Increases surface area
- Forms membrane
- Makes possible the use of butter, frozen cream, etc.
- Controls “whippibility” and churning during freezing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

In the ice cream process, what is chilling and aging the mix?

A

Mix is cooled to 2-5°C
- Then aged at this temperature
- Aging allows time for:
fat to cool down & crystallize,
for proteins & polysaccharides to fully hydrate & stabilise gel formation
- Aging carried out for 4-24 h depending on stabiliser used (gelatine takes 24 h)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

In the ice cream process, what is freezing?

A
  • Soft freezing (~50% water is frozen)
  • Beating to incorporate clean air & freezing in scraped surface heat exchanger
  • Fine even foam required = freezing rapid
  • Temperature at outlet of freezer -1 to -9°C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

In the ice cream process, what is packaging?

A
  • when soft unless other steps required, e.g.: addition of fruits, nuts, candy, cookies
  • At this stage, consistency same as soft serve ice cream 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

In the ice cream process, what is hardening?

A

~90% water frozen
- ice cream cooled to ~ -35°C in a blast freezer = should be as rapid as possible to ensure small ice crystals
- Must store ice cream at < -18°C after hardening
- Poor storage conditions are detrimental to ice cream quality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

In the ice cream process, what is the blending of mix ingredients?

A
  • Usually heated to 50-60°C to effect good mixing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the shelf life of ice cream?

A
  • Only consideration is texture should be smooth
    2 main problems:
  • coarseness due to large ice crystals = slow cooling or melting/refreezing or fluctuating storage temperatures
  • “sandiness” due to lactose crystals = can occur if lactose:water ratio is wrong
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

How do you maintain shelf life of ice cream?

A
  • Formulate the ice cream properly
  • sugar considerations
  • stabilisers: bind free water
  • Freeze the ice cream quickly
  • Harden the ice cream rapidly
  • Avoid temperature fluctuations during storage & distribution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What are the two main chicken hybrids?

A
  • cobb and ross
  • have been selectively bred for their growth, feed conversion (can feed them anything)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Do you want to cross breed chickens?

A

Yes as this creates stronger, more robust & health of cross is greater than the average of their parents (male parent = good muscling & body weight, while breeder hen = capacity to lay plenty of fertile eggs to be hatched into meat chickens)
- Don’t want inbreeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are the 2 main bacteria present that can cause illness in poultry?

A

salmonella and campylobacter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What are the Physio-chemical Characteristics of butter?

A

Main constituents (normal salted butter):

- Fat (80-82%; and maybe some milk solids-not-fat)
- Water (15.6-17.6%) = dispersed in fine droplets so butter 
looks dry
- Salt
- Protein, calcium, phosphorous
- Fat soluble vitamins A, D & E :
Colour should be uniform 

Should be dense and taste clean 

Should be of smooth consistency so easy to spread & melt readily on tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is the ice cream mix made up of?

A
  • Fat
  • Milk solids-non-fat (MSNF)
  • Sweeteners
  • Stabilisers
  • Emulsifiers
  • Flavours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is the purpose of fat in the ice cream mix?

A
  • Gives creaminess & improves melting resistance by stabilising air cell structure of ice cream.
  • Whole milk, cream, butter or anhydrous milk fat (AMF)
  • Milk fat can be replace by vegetable fat = refined or hydrogenated coconut oil & palm kernel oil most commonly used
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What is the purpose of Milk solids-non-fat (MSNF) in the ice cream mix?

A

From whole milk, skim milk, condensed milk, milk powders &/or whey powder = highly nutritional value. Helps to stabilise structure of ice cream due to water-binding & emulsifying effect. Has positive influence on air distribution in ice cream during freezing process = leading to improved body & creaminess

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What is the purpose of sweeteners in the ice cream mix?

A

Increases solids content. Gives level of sweetness consumers prefer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What is the purpose of stabilisers in the ice cream mix?

A

Increase viscosity of mix & creates good texture. Control growth of ice crystals & improve melting resistance = producing firmer product (if not present = product becomes coarse & icy very quickly due to migration of free water & growth of existing crystals).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What is the purpose of emulsifier in the ice cream mix?

A

Include: egg yolk solids, glycerol monostearate (GMS). Help in developing fat structure & air distribution for smooth eating & good meltdown desired during freezing; each molecule contains a hydrophilic portion & a lipophilic portion = Act to reduce interfacial tension or force that exists between two phases of emulsion.Also controls excess churning of fat during the freezing 
process.

66
Q

What is the purpose of flavours in the ice cream mix?

A

Essences added before freezing. Solids (nuts, fruit, etc) added after freezing. Chocolate added to mix before pasteurisation as it often contains undesirable bacteria…

67
Q

What are the processing steps of butter?

A
  • aging
  • churning
  • working
  • salting
  • working post salting
  • packaging and storage
68
Q

In butter processing, what it the aging step?

A

Cream is subsequently cooled so a proportion of fat crystallises. If cooling rapid = crystals will be many and small. If cooling gradual = will have fewer but larger crystals & this gives butter a softer texture. Takes 12-15 hours

69
Q

In butter processing, what it the churning step?

A

After aging, cream then pumped into churn. Cream first whipped with air. Breaks down fat globules = fat coagulates into butter “grains” = fat content of remaining liquid (buttermilk) decreases. “Phase inversion” occurs, where there is change from a fat-in-water emulsion (cream) to a water-in-fat emulsion (butter) = fat is the “continuous phase” & water in the form of small droplets, is the “discontinuous phase”. Thus, cream split into two components = butter grains & buttermilk (= skim milk + milk fat globule membrane material).Traditionally, machine stops when grains have reached a certain size & buttermilk is drained off. In continuous butter maker: draining of buttermilk is continuous

70
Q

In butter processing, what it the working step?

A

Done after draining = butter is “worked” or “plasticised” (kneaded together) to continuous fat phase containing finely dispersed water phase. Breaks up embedded pockets of buttermilk or water into tiny droplets which are evenly dispersed in the fat. Fat is the “continuous phase” & water in the form of tiny droplets is the “discontinuous phase”. Small water droplets prevent bacterial growth = poorly “worked” butter = uneven distribution & sizes of water droplets = allow bacterial growth. Rarely now wash the butter to remove any residual butter milk & milk solids

71
Q

In butter processing, what it the salting step?

A

Salt used to improve flavour & shelf-life, acts as a preservative. In batch production salt is spread over surface of worked butter. In continuous butter making, salt slurry is added to butter 


72
Q

In butter processing, what it the working post salting step?

A

Butter worked vigorously so salt is evenly distributed. Also influences product characteristics: aroma, taste, keeping quality, appearance & colour

73
Q

In butter processing, what it the packaging and storage step?

A

Finished butter is discharged into packaging unit. Then put into cold storage

74
Q

What are the types of yogurt?

A
  • Set = incubated in container; additives such as fruit sink to bottom
  • Stirred = incubated in tanks; gel disrupted by stirring, pumping, filling; additives well suspended
  • Drinking type: similar to stirred type, but coagulum is broken down to a liquid
  • Frozen type: incubated in tanks & frozen like ice cream
  • Concentrated: incubated in tanks, concentrated & cooled before being packed, e.g.: Greek yogurt
  • With Probiotics
- Some now also contain ‘probiotics’ or ‘therapeutic’ starters. These produce acid slowly compared with normal yoghurt starters. Common to add ingredients known as prebiotics, which will aid in growth of the probiotics in the colon
75
Q

What is ripened butter?

A

Made from cream cultured with lactic acid bacteria which produce diacetyl & lactic acid. Has reduced pH due to lactic acid.

76
Q

What is the process of butter?

A

Cream in storage tanks goes to pasteurisation (microbes and enzymes destroyed)
- Cream is stored cold for at least 4 h at ~5 °C before churning (to induce growth of some fat crystals & facilitate churning as pasteurisation causes fat in globules to liquefy)
* Aging tank
- Here cream subjected to heat treatment program designed to give fat required crystalline structure when solidifies upon cooling
- Program chosen according to composition of
butterfat (e.g. in terms of iodine value, which is a measure of unsalted fat content)

77
Q

What are the nutritional properties of chicken?

A
  • high quality protein
  • low in fat
  • Good source of phosphorus, iron, copper, zinc & vitamins B12 & B6
  • Dark meat (leg, thigh) higher in fat than white meat (breast)
  • Skin high in fat
78
Q

What does Poultry products meeting consumer’s expectations depend upon?

A
  • Conditions surround various stages in bird’s development from fertilized egg through production & processing to consumption
  • appearance, texture & flavour are of primary concern to food industry & consumer 

79
Q

What are the characteristics of the egg shell?

A

-Colour comes from pigments in outer shell layer = white to brown = breed determines shell colour
- Accounts for 9-12% of total egg weight
- First line of defence against bacterial contamination
- Largely composed of calcium carbonate , plus small amounts of magnesium carbonate, calcium phosphate & other organic matter

80
Q

What are the characteristics of the egg white?

A
  • Egg albumin in raw eggs is opalescent & doesn’t appear white until beaten or cooked
  • If yellow or greenish = riboflavin present
  • Cloudiness = due to presence of CO2 that’s not had time to escape = indicates very fresh egg
81
Q

How are eggs processed?

A
  • Moment egg is laid = physical & chemical changes begin to reduce freshness
  • Automated gathering belts gather & refrigerate eggs frequently
  • Gathered eggs moved into refrigerated holding rooms = temperatures between 5- 7°C & humidity relatively high to minimise moisture loss 

82
Q

What is the major factor affecting taste of chicken?

A

bird age at slaughter

83
Q

What is the minor factor affecting taste of chicken?

A

bird stain, diet, environmental conditions (litter, ventilation etc), scalding temperatures, chilling, product packaging, storage

84
Q

What affects taste of chicken?

A
  • When poultry cooked = flavour develops from sugar & amino acid interactions, lipid & thermal (heat oxidation) & thiamine degradation
  • Poultry lipids & fats unique, & combine with odour to account for characteristic flavour
  • Affected by few factors during production & processing
85
Q

What are the three factors affecting meat quality?

A

Live production + animal state at production + poultry processing

86
Q

What affects meat tenderness?

A
  • feeding
  • genetics
  • species
  • age
  • muscle to muscle
  • carcase suspension
  • electrical stimulation
  • mechanical tenderising
  • chemical tenderising
  • marinating
  • freezing
  • thawing
  • cooking
  • carving
87
Q

How does feeding affect meat tenderness?

A
  • What animal is fed doesn’t directly influence tenderness.
  • Animals “finished” with grain reach slaughter weight sooner than animals “finished” to same slaughter weight (grass fed) = thus grain-fed animals usually sightly more tender as they are slaughtered at younger age.
88
Q

How does genetics affect meat tenderness?

A

Accounts for ~45% of observed variation in cooked beef tenderness. One of the main reasons for such wide tenderness differences existing among identical meat grades & cuts

89
Q

How does species and age affect meat tenderness?

A

Tenderness variation = beef > lamb > pork > veal. Due primarily to chronological age of animal at time of slaughter.
Tenderness decreases as animal gets older = due to collagen.Pork & lamb from older animals = processed into sausage items, so toughness not a proble

90
Q

How does muscle to muscle affect meat tenderness?

A

Considerable variation among muscles within any species = e.g. tenderloin much more tender than fore shank or heel

Connective tissue amount present

Carcase Suspension; Muscle stretching during carcase chilling affects tenderness.

91
Q

How does electrical stimulation affect meat tenderness?

A

Done to “hot” carcases immediately after slaughter increases 
tenderness. Beef carcases = 1 min of high-voltage electrical current = improves tenderness of many carcase cuts

92
Q

How does mechanical tenderising affect meat tenderness?

A

Grinding is very popular means of increasing meat tenderness. Cubing another means of mechanically meat tenderising = small blades of cuber severs connective tissue, breaking it into smaller pieces

93
Q

How does chemical tenderising affect meat tenderness?

A

Salt at certain concentrations increases meat tenderness. Salt tenderises by softening connective tissue protein (collagen) into more tender form. Hence cured meats (e.g. hams) more tender than uncured meats. Vegetable enzymes tenderise meat & used commercially & in homes. Work by degrading/dissolving connective tissues, collagen & elastin.

94
Q

How does marinating affect meat tenderness?

A

Improves tenderness & adds taste variety. Basic ingredients include salt, acid (vinegar, lemon), & enzymes (papain, bromelin, ficin). Sometimes alcohol added for flavour. Addition of olive oil seal surfaces from air, result in meat fresher & brighter for longer

95
Q

What is Tenderness, juiciness & flavour?

A

components of meat palatability; tenderness can considerably vary from one cut to next

96
Q

How does freezing affect meat tenderness?

A

When meat frozen very quickly = small ice crystals form. When meat frozen very slowly = large ice crystals form = disrupt components of meat muscle fibres & slightly increase tenderness BUT also increase juice loss upon thawing (less juicy and tender)

97
Q

How does thawing affect meat tenderness?

A

Done slowly in refrigerator results in greater tenderness compared with cooking from frozen. Slow thawing minimises effect from cold shortening & reduces moisture loss. Microwave thawing should be done on low power

98
Q

How does cooking affect meat tenderness?

A

As progresses, contractile meat proteins become less tender & major connective tissue protein (collagen) become more tender

99
Q

How does carving affect meat tenderness?

A

For carcase cuts & wholesale cuts = cut at right angles to length of muscle = severs maximum amount of connective tissue & bone more evenly distributed in that area. Consumers should carve cooked meat at right angles to length of the muscle fibre or “against the grain” to achieve maximum tenderness. Cutting “with the grain” = “stringiness” & thus less tenderness

100
Q

What does chicken texture depend on?

A
  • rate & extent of chemical & physical changes occurring in chicken muscle as it becomes meat
  • Affected by anything interfering with rigor mortis e.g struggling before or during slaughter = rigor mortis forms faster = toughness of muscle due to reduced energy in live bird…
  • Environmental stress (hot/cold temps.) exposure before slaughter create similar outcome
  • High pre-slaughter stunning temperatures, high scalding temperatures, longer scalding times = cause toughness of poultry meat
  • For boneless = influenced by amount of time between death & deboning
  • Muscles deboned during early post-mortem become tough as they still have energy to contract. Avoided by aging meat 6-24 hours before.
  • post-slaughter electrical stimulation used immediately after death to hasten rigor development & reduce aging time before deboning = electricity applied to dead bird, energy used up & rigor mortis entered at faster rate, meat deboned within 2 hours post-mortem instead
101
Q

Why does rigor mortis occur?

A

Animal dies, blood stops circulating, muscles receives no new oxygen or nutrient supplies, no oxygen or nutrients cause muscles to run out of energy, they contract & become stiff

102
Q

What is the appearance of chicken meat?

A
  • affected by bird age, sex, strain, diet, intramuscular fat, meat moisture content, pre-slaughter conditions
  • meat colour depends on presence of myoglobin & haemoglobin
  • Breast muscle most susceptible to discolouration
  • Discolouring also caused due to environmental temperatures or stress in live handling or bruising

103
Q

What is ice cream?

A
  • Unfermented
  • Is greater than 10% milkfat & as high as 16% fat in premium products
  • Want it to contains 9-12% milk solids-not-fat:
    Proteins = caseins & whey proteins Carbohydrates = lactose
    Contains 12-16% sweeteners = combination of sucrose & glucose-based corn syrup
    Contains 0.2-0.5% stabilisers and emulsifiers * 55-64% is water that comes from milk
    The above values are percentage by weight in mix, but when frozen, half of the tub is air
104
Q

How is chicken meat processed?

A
  • Processing companies generally contract out growing of chickens to contracted chicken growers
  • Growers own the farm & provide management, shedding, equipment, labour, bedding but does not own the chickens, or provide feed, medication & technical advice
  • Contracted growers paid a growing fee = currently varies from 59-73/80¢/bird
  • culling chickens ‘thinning out’ or ‘partial depopulation’ = may be done up to five times, depending on chicken company’s requirements for different sized chickens; allows more space & helps with optimal barn temperature, plus air & litter quality
  • First harvest might occur as early as 30-35 days, & last harvest at 55-65 days
  • Chickens often harvested at night = its cooler & birds more settled
  • Birds picked up by specialised contract ‘pick-up’ crews under low lighting conditions for calm & easy handling
  • Birds usually caught by hand, placed into plastic crates for good ventilation & protection from bruising during transport
  • Sometimes chickens collected by machines using conveyor belts to move birds from barn floor & deposits them into crates
  • Crates/modules then handled by forklift equipment & onto trucks for transport to the processing plant
105
Q

What are the properties of milk as a beverage?

A
  • Regular or full-fat: 3.2% to 3.8% milk fat
  • Reduced-fat: ~2% milk fat
  • Low-fat: <1.5% milk fat
  • Skim/no-fat: 0.15% milk fat. Milk solids (water removed from liquid milk) added to optimise the taste
106
Q

What are the issues with precooked meat products?

A
  • Should be handled carefully to avoid recontamination & incubation of spoilage microbes
  • most serious with repeated warming & chilling
  • Canning = subjects meats to sufficient heating to control spoilage microbes, while sealing prevents recontamination & favourable conditions for microbial growth
107
Q

How to best cook meat?

A
  • Cuts low in connective tissue = steaks = dry heat cooking including pan frying, grilling or BBQ, meat flavour develops before contractile proteins have opportunity to become significantly less tender
  • Cuts high in connective tissue = those from fore shank, heel & chuck = long & slow cooking at low temp using moist heat such as braising, results in tough collagen converted into tender gelatine = more tender than with dry heat
108
Q

What are the processing steps of cheese?

A
  1. Cheese milk clarified, separated & standardised
  2. Pasteurisation: High-Temperature Short-Time Pasteurization: Disrupts fat globules & increases fat surface area where casein particles absorb. Results in a soft, weak curd at renneting.
  3. Additives
    - Calcium chloride added to replace calcium lost during pasteurisation. Aids coagulation & reduces amount of rennet required.
    - Colour may be added, Hydrogen peroxide sometimes used alternative treatment for full pasteurisation
    - Lipases (inactivated during pasteurisation) added to ensure proper flavour development
    - Addition of starter cultures = basis of cheese making: Lactic acid bacteria (LAB) ferment lactose to produce lactic acid and gas. pH is lowered & assists coagulation, helps prevent spoilage bacteria from growing
    - After starter culture inoculation, milk held for 45-60 min at 25- 30°C = ensures bacteria are active, growing
  4. Coagulation
    - Gel formed by destabilising casein micelles causing them to aggregated & form network that partially immobilises water & traps fat globules in newly formed matrix 
 

    - Rennet most often used for enzyme coagulation 

    In acid treatment:
    - Acid curd more fragile than rennet curd due to loss of calcium
    - Acid coagulation naturally achieved with starter culture or artificially
    - Acid coagulated fresh cheese: cottage and cream cheese
    In heat + acid treatment:
    - Heat causes denaturation of whey proteins which interact with caseins
    - Addition of acid causes caseins to precipitate with whey proteins
    - 90% of protein can be recovered
  5. Curd treatment
    - After milk gel reach desired firmness, its cut into small pieces (increases area for whey to be released = determine moisture content) 

    - Curd pieces immediately begin to shrink & expel whey (syneresis) 

    -Increase in temperature causes protein matrix to shrink
    - lactose to lactic acid increases; contributes to curd particles shrinking 

    -
When curd reached desired moisture & acidity = separated from whey
    - Whey removed from the top or drained by gravity 

    - Curd-whey mixture may also be placed in moulds/“hoops” for draining 

    - Some cheese varieties include curd washing: increases moisture content, reduces lactose content, final acidity, decreases firmness
    Salting; Reduces bacterial growth of starter & others, Moisture changes (water expelled), Smoothens texture by replacing Ca with Na 

  6. Ripening
    - Varies from weeks to years; Temperature, humidity & time controlled -until characteristic flavour, body & texture achieved
    - Cheeses covered to protect against moisture loss & mould growth – dipped in wax, vacuum packed 

    - Degradation of lactose, proteins & fat carried out by ripening agents
109
Q

How is yogurt produced?

A
  • Milk is clarified, separated into cream & skim milk, then standardised to achieve desired fat content
  • Mixed: Various ingredients blended together in mix tank equipped with powder funnel & agitation system -> fortification of milk to increase milk solids-not-fat: improves consistency & flavour. Pectin or starch or gelatine added sometimes to increase viscosity. Can use fat substitutes.
  • Mixture then pasteurised
    Varies = 85°C/30 min to 90-95°C/10-20 min
    Helps formation of casein network
    Increases gel firmness and decreases syneresis (release of whey from gel)
    Shortens coagulation time, increases pH at which coagulation occurs
  • Then homogenised (at 50-60°C) = to improve viscosity & firmness of coagulum; Even dispersion of constituents, solids-non-fat & fat
  • Mix cooled to temperature optimum for starter culture growth (40-45°C)
  • Starter cultures: (ST) & (LB)
    ST grows faster & produces both acid & CO2 which stimulates LB growth.
    Proteolytic activity of LB produces stimulatory peptides & amino acids used by ST.
    Microbes ultimately responsible for typical yoghurt flavour & texture. Incubated till firm gel forms (5-7 h)
  • Stir (for stirred yoghurt) & cool
  • Add fruit if required

  • Pack, store, dispatch
110
Q

How are plant based meat products made?

A
  • Extrusion method
  • Vegetable protein combined with flavour, colour & other ingredients
  • Formed into a plastic mass in a cooker-extruder
  • Mass forced through a die under pressure to form beef-like strips or other characteristic meat shapes
111
Q

What are the practices of milk production?

A
  • Raw milk fresh is almost sterile
  • Post-milking handling MUST maintain milk’s nutritional value & prevent deterioration
  • Most cows milked twice a day (some farms milk 3 or 4 times/day)
  • Raw milk immediately cooled from the cow’s body temperature to below 5°C
  • Then stored at farm under refrigeration until pick up by insulated tanker trucks
  • When raw milk pumped into tanker, a sample is collected for later lab analysis
112
Q

How is milk processed?

A
  • Raw milk arriving at milk processing plant is tested for quality
    Quality assurance of raw milk:
  • temperature
  • flavour & odour
  • Composition
  • Antibiotics
  • Freezing point depression
  • pH/Acidity
  • Butterfat (BF) and solids-non-fat (SNF) of raw milk also analysed (vary according to time of year, breed of cow & feed supply)
  • Price is determined on BF & SNF content, and volume
  • Once passes receiving tests, milk pumped into large refrigerated silos of processing plant
113
Q

How is milk seperated?

A
  • centrifugal separation
  • Separates cream & skim portions of milk
114
Q

What is butter fat?

A
  • Accounts for different types of products; whole milk, non-fat
  • Two streams produced during separation of whole milk: fat-depleted stream (produces the beverage milks) and fat-rich stream (cream)
  • further processing; butter, ice cream
  • Sold to processing industries = higher fat content than retail sold creams
  • “Plastic” cream produced from certain types of separators. Remains an oil-in-water emulsion
115
Q

What is milk pasteurisation?

A
  • heating raw milk to kill all pathogens
  • Some harmless bacteria may survive heating process; Cause milk to “go sour” (refrigeration slows growth bacteria)
  • not sterilisation as doesn’t remove all bacteria
  1. Low-temperature longer time (LTLT) pasteurisation: A batch method; Heats milk to at least 63°C for at least 30 min OR 65°C for 15 min. Can cause a “cooked” flavour, so not always used for fluid milk products
  2. High-temperature/short time (HTST) pasteurisation: A continuous method heating milk to 72°C for at least 15 sec. Milk immediately cooled to below 4°C & packed into plastic bottles or plastic-coated cartons
  3. Ultrapasteurisation: 135°C for 2 to 5 sec, followed by rapid cooling to 7°C or lower. Sterilisation of milk occurs when heated to 137°C - 150°C for 2 to 6 sec = called ultrahigh temperature (UHT) processing
    -UHT milk in cartons, doesnt require refrigeration until its opened
116
Q

How long does raw milk have to be processed after its receipt?

A

72 h

117
Q

How is processed milk packaged?

A
  • various size containers
  • under strict sanitation; prevent introduction of microbes
  • Daily washing and sophisticated automatic “Clean-in-Place” (CIP) systems used; minimises manual handling, reduces contamination risk
  • Packaged products to cold storage warehouse (stored for short time)
  • Transported to supermarkets on refrigerated trailers
118
Q

What is the nutrition of processed milk?

A
  • Vitamins may be added to full fat & reduced fat milks
  • Vit A & D often added
  • Supplemented in form of a water-soluble emulsion
  • Vit A lost during fat separation & heating, while Vit D not present
  • addition of milk solids to meet standards
  • Solids represent the natural mineral (Ca, Fe), protein (casein) & sugar (lactose) portion of nonfat dry milk
119
Q

What is milk homogenisation?

A
  • Cream portion prevented from rising to top of package
  • Milk forced under high pressure through narrow gap
  • Breaks up the butterfat globules to small sizes
  • Such small globules will not coalesce (stick together)
  • Nutrition or quality not affected
120
Q

How is quality control done for processed milk?

A
  • samples analysed for microbial presence; standard plate count (SPC) and “Ropey” milk test
  • Regular calibration equipment used to analyse butterfat & solids-not-fat
  • use-by date on package
  • Most companies guarantee quality & freshness of product for at least 7 days past printed date on package
  • Samples of each product packaged each day are saved to confirm freshness 7 days after use-by date
121
Q

What are Concentrated and dried dairy products?

A
  • Concentrated milk products obtained through partial water removal
  • Dried dairy products have less than 4% water usually
  • Benefits of both processes include: - increased shelf life, convenience, product flexibility, decreased transportation costs & storage

Products include:
Evaporated Skim or Whole Milk
Sweetened Condensed Milk
Condensed Whey
Milk Powder
Whey Powder
Whey Protein Concentrates (WPC)

122
Q

What is whey protein concentrate?

A
  • After clarification & pasteurisation, whey is cooled & held till calcium phosphate complex stabilise
  • Whey processed using ultrafiltration
  • Low molecular-weight compounds (e.g. lactose, minerals, vitamins & non-protein nitrogen) are removed during ultrafiltration
  • Proteins become concentrated in retentate
  • Reverse osmosis can be used to concentrate whey prior to vacuum evaporation
  • Lactose crystallisation is induced before spray drying to decrease hygroscopicity; Accomplished by quick cooling in flash coolers after evaporation; Crystallisation continues in agitated tanks for 4 to 24 h
  • A fluidizer bed may be used = produce large agglomerated particles - ultrafiltration, retentate is pasteurised, may be evaporated, then dried (Spray drying at lower temp than milk to avoid protein denaturation
123
Q

What is whey powder?

A
  • produced by same methods as other milk powders
  • Reverse osmosis can be used to concentrate whey prior to vacuum evaporation
  • Lactose crystallisation is induced before spray drying of whey concentrate to decrease hygroscopicity; Accomplished by quick cooling after evaporation; Crystallisation continues in agitated tanks for 4 to 24 h
  • A fluidizer bed may be used = produce large agglomerated particles
124
Q

What is milk powder?

A
  • standardised & given a heat treatment more severe than pasteurisation; cause lipolysis (fat breakdown) during storage
  • Milk evaporated prior to drying
  • Homogenisation to decrease free fat content
  • Spray drying method mostly used for milk powder production
  • Post-spray drying, powder packed to protect from moisture
  • Whole milk powder (WMP) can be stored for upto 6 months
  • Skim milk powder (SMP) processing similar to WMP
  • Instant milk powder produced by partially rehydrating dried milk powder particles = become sticky; Water then removed by drying = increased amount of air between powder particles
125
Q

What is sweetened condensed milk?

A
  • longer shelf life due to sugar; increases osmotic pressure (prevents microbial growth)
  • Only heat treatment (85°C to 90°C for several sec) is after raw milk been standardised; destroys microbes; inactivates lipases & proteases; decreases fat separation; inhibits oxidative changes
  • Sugar is added before & after evaporation, to avoid viscosity changes
  • then cooled & lactose crystallisation is induced
  • Milk is inoculated with powdered lactose crystals, then rapidly cooled with agitation
  • Product then packed in small cans
126
Q

What is evaporated milk?

A
  • Concentrated at low temperatures by vacuum evaporation: results in little cooked flavour
  • second standardisation done to balance salts (protects milk from extensive heat treatment)
  • After salt balanced, product is quite perishable = fat easily oxidised
  • Evaporated milk can be packed in cans & sterilised in an autoclave
  • Continuous flow sterilisation is followed by packaging under aseptic conditions
  • Sterilisation process produces a light brown colouration, & can be stored for up to a year
127
Q

What is condensed whey?

A

Whey resulting from cheese making is condensed by evaporation

Contains lactose, lactoglobulin, lactalbumin & water

Fat generally removed by centrifugation & churned as whey cream or used in ice cream

128
Q

How can fish be classified?

A
  1. saltwater and fresh water varieties
  2. basis of fat content:
    - Lean = <2% fat
    - Fat = >5% fat
129
Q

What is another word for fish?

A

finfish

130
Q

What are shellfish?

A
  1. Include molluscs
    - are soft-bodied & partially or wholly enclosed in hard shell composed of minerals, E.g. = oysters, clams, abalone, scallops & mussels
  2. Include crustaceans
    - are covered in crust-like shell & have segmented bodies E.g = prawns, lobsters, crabs, Morten Bay bugs
131
Q

What is the correct storage for seafoods?

A
  • Fish & shellfish must never sit unrefrigerated for long
  • If have bruises or punctures = will spoil more rapidly
  • Fish & shellfish should be cooked within 2 days of purchase, and if not, frozen
  • Fish sitting in own juices deteriorates more rapidly
  • When thawing - do in fridge to avoid drip loss & taste, texture, aroma & appearance adversely affected
  • for crustaceans, keep damp but not placed on ice & freshwater or airtight container will kill them
  • Store lobsters & crabs in moist packaging in refrigerator, but not in airtight containers
  • lobsters remain alive for ~24h
  • Should scrub scallops, mussels, clams or oysters under cold water, just before opening or cooking
  • soaking them in water with flour or cornmeal to encourage them to eat to clean out the grit only shortens their life
132
Q

What are fish by-products?

A
  • intestines, heads & gills not used for human food; ground up, dried & for use as animal feed; some fish meal used as fertiliser
  • Fish protein concentrate (FPC) or fish flour
  • produced from dehydrated & defatted fish
  • high-quality protein source = used to supplement breads & cereal products
  • Roe = mass of eggs & sacs of connective tissue enclosing 1000s of eggs
  • cooked by parboiling, or eaten salted & dried, smoked, or preserved in brine (caviar = sturgeon roe)
133
Q

What contributes to fish spoilage?

A
  • Fresh fish held at 16°C only good for 1 day or less, whereas At 0°C = fish may remain good for 14 to 28 days
  • Happens quicker than meat = bacteria on skin & in digestive tract attack all tissues
  • once fish killed, & these bacteria often adapted to cold temperatures
  • Fish struggle when caught = convert glycogen to lactic acid before death
  • Fish fat has phospholipids containing trimethylamine oxide (TMAO) which regulates osmotic pressure in living fish cells. Fish die = TMAO converted by bacterial enzymes (from fish) to “fishy” smelling liquid substance trimethylamine
134
Q

What are the properties of fresh fish?

A
  • eyes should be bright, clear, & full-often protruding, become cloudy and pink as fish decomposes
  • Skin should be shiny, almost metallic with unfaded colour, skin becomes less distinct as fish decomposes
  • Scales should be brightly coloured & tightly attached to skin
  • Gills should be red & free of slime = gills change colour as fish ages, gradually becoming light pink, grey & eventually brownish & greenish
  • Flesh should be firm, elastic & not
    separated from the bones = becomes soft, slimy & slips away from bone as fish decomposes
  • Fillets should have fresh cut appearance & colour resembling freshly dressed fish
  • Odour should be fresh or mild (not fishy)
135
Q

How is seafood regulated?

A
  • standards by the Federal and State government
  • Hazard Analysis and Critical Control Point (HACCP) principles in place
136
Q

Examples of seafood products

A
  • Whole or round fish = fish just as it comes out of water
  • Drawn fish = only entrails removed
  • Dressed fish = scaled & eviscerated, & usually head, tail & fins removed
  • Steaks = sections of larger sizes of dressed fish
  • Fillets = fish sides cut lengthwise away from backbone
  • Sticks = uniform fish pieces cut lengthwise or crosswise from fillets or steaks
  • Nuggets = like fillets but only smaller
    Some fish manufactured into:
  • breaded, formed & imitation products
  • cured or canned products
137
Q

How can shellfish be marketed?

A
  • in the shell
  • shucked (removed from shell)
  • headless (prawns)
  • as cooked meat
138
Q

What is surimi?

A
  • paste made from fish
  • Machines similar to deboning machines used to obtain minced fish flesh from filleting wastes & underutilised fish species
  • Minced fish flesh is washed to remove solubles
  • Left over odourless, flavourless, high- protein product called surimi
  • Can be combined with other flavours, colours & anti-denaturants before freezing
139
Q

How is seafood preserved?

A
  • drying, salting, curing or smoking
  • Refrigeration, freezing & canning
  • Large fish boxes frozen. When fish individually frozen = glazed with layers of ice to protect fish surface from oxidation & freezer burn
  • glazing done by dipping fish/prawns in cold water & then freezing a layer before dipping fish again
  • Pre-breaded, precooked fish sticks also frozen
  • High-quality, low-fat fish can be frozen, Fish with higher fat = salmon, tuna & sardines often canned
  • fish oil, vegetable oil or water often added before can sealed closed
  • Typical canning operation:
  • thaw frozen fish received from fishing vessel, eviscerate, clean & sort, precook, cool & separate meat, compact meat to fit can, vacuum seal cans & sterilise in a retort, label cans, packaging, storage & dispatch
140
Q

When is seafood grading done?

A
  • Done after inspection & determines quality level
  • Only products that have an established grade
  • standard can be graded
141
Q

What is fish grading based on?

A
  • Appearance = flesh consistency, odour, eyes, gills & skin
  • Discolouration = refers to any colour not characteristic to species
  • Cutting & trimming defects = include body cavity cuts, improper washing, improper deheading & evisceration defects
  • Improper boning (for boned styles = fillet only) = refers to presence of unspecified bone or bone piece
142
Q

What is the composition of fish?

A
  • good source of B vitamins (B6, B12), biotin & niacin
  • vitamins D & A found mainly in fish liver oils, but some high-fat fish good source of vit A
  • good source of minerals = iodine, phosphorus, potassium & zinc
  • canned with edible bones (e.g. salmon or sardines); calcium
  • Oysters; iron & copper
  • Saltwater fish; excellent iodine source
143
Q

What is the composition of fish and shellfish?

A
  • low in fat, good source of protein, minerals & vitamins
  • complete protein source
  • fat is unsaturated
  • cholesterol content similar to red meat & poultry BUT polyunsaturated = maybe allowed for some fat- & cholesterol- restricted diets
144
Q

What are the steps in fish processing?

A
  1. receiving and weighing fish at live processing plant
  2. holding fish alive until needed
  3. stunning
  4. deheading
  5. eviscerating
  6. skinning
  7. chilling
  8. size grading
  9. packaging
  10. transportation of finished product

Some fish will also include freezing

145
Q

What is ultra-processed food?

A
  • food products that are convenient (ready to eat), durable (long shelf-life), highly profitable, highly attractive, hyper palatable
  • derived from foods with little or no whole food
  • low nutritional quality
  • high glycemic index, low satiety potential
  • cheap
146
Q

What are methodologies for ultra-processed food?

A
  • Hydrogenation & hydrolyzation
  • Extrusion
  • Moulding (e.g. for production of chocolate, bread, biscuits, confectionery & pies)
  • Pre-processing for frying
147
Q

How are ultra processed foods made palatable?

A
  • colourings
  • flavourings
  • emulsifiers
  • thickeners
  • other cosmetic additives (e.g. sorbic acid, benzoic acid and their salts - sodium benzoate)
148
Q

Unprocessed/minimally process food

A

foods which did not undergo processing techniques such as pasteurising, fractioning, grinding
e.g legumes, fruit, veg, eggs, chicken

149
Q

Processed culinary ingredients

A

Obtained from minimally processed foods and used to season, cook and create culinary ingredients, edible wax
Home cooking that you know all the ingredients going in
E.g salt, sugar, vegetable oils, butter

150
Q

Processed Foods

A

Unprocessed or minimally processed foods or culinary dishes which have added culinary processed ingredients. Necessarily industrialised. Long shelf life.
E.g bread, cheeses, pastes, meal/fruit/veg bottled in salt or sugar solution

151
Q

Ultra processed foods

A

Food products derived from foods or parts of foods added with cosmetic additives, not used in culinary. Longest shelf life.
E.g breast milk substitutes, cookies, ice cream, nuggets, soft drink

152
Q

UPF in Australia

A
  • Contribute to 42.0% of energy intake
  • Unprocessed or minimally processed foods = 35.4%
  • Processed foods = 15.8%
  • Processed culinary ingredients = 6.8%
153
Q

UPF consumption and health

A
  • the more UPF, the higher amount of free sugars; total, saturated & trans fats; sodium & dietary energy density consumed
  • associated with increase in risk of overweight/obesity. high waist circumference, low HDL-cholesterol levels & metabolic syndrome
  • less common but still associated with cardiometabolic risk, higher risk of CVD, cerebrovascular disease, depression & all-cause mortality
154
Q

UPF in pregnancy

A
  • high impact even on unborn child
  • maternal nutrition important
  • when child is born, if has been impacted, increases their risk of allergies, asthma, etc
  • linked to post natal depression, gestational diabetes
155
Q

UPF on the gut brain axis

A

Relationship with dysregulation of gut microbiota & its influence on the development of cognitive decline

156
Q

Foods you may not realise are UPF

A

Breakfast cereals: contain maltodextrins, processed proteins & fibres, and colours

Protein & Muesli Bars and Balls: contain processed fibres & proteins, non-caloric sweeteners
& invert sugars glucose & fructose

Plant-based “milks”: contain emulsifiers, vegetable gums & flavours

Packaged Breads: some contain emulsifiers, modified starches

Yoghurts: contain additives like thickeners, non-caloric sweeteners
or flavours (so choose plain yoghurts)

Meal bases & sauces: typically contain thickeners, flavour enhancers & colours

157
Q

Are all UPF bad?

A
  • displace nutritious meals
  • sometimes choices are limited
  • minimally processed foods need to be more available and affordable
158
Q

Boxed beef

A
  • vacuum sealed meat: prevent spoilage and shrinkage
  • extended shelf life
  • bones and fat removed
  • smaller portions
  • reduces shipping and labour costs
159
Q

Meat fat and tenderness adds to;

A

juiciness, tenderness, flavour

160
Q

Meat tenderness affected by;

A

genetics, species, age, feeding (indirect effect), muscle to muscle (tenderloin more tender that foreshank), carcase suspension (muscle stretching), electrical stimulation (increases tenderness), chilling rate, quality grade, mechanical (grinding), chemical (salt softens connective tissue), marinating, freezing, thawing, cooking (as progresses, contractile meat becomes less tender and collagen becomes more tender), carving (cutting against the grain maximises tenderness)

161
Q

Meat freezing

A
  • meat fat eventually oxidises
162
Q

is beef or pork cooked longer?

A

Pork due to a parasite

FOOD2000 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions