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Key Food Science & Communication Vocabulary

Consumer Documents and Design Principles

  • Definition
    • Written material intended for the general public; not academic or scientific.
  • Audience Analysis
    • Identify target segment (students, seniors, new moms, business people, general public).
    • Trigger examples:
    • Students → fast-food, low-cost, trendy flavours.
    • Seniors → low-cost, easy prep, comfort food.
    • New moms → time-saving, healthy.
    • Business → portable, non-messy foods.
  • Visual/Layout Rules
    • Colour: light background, dark text, avoid red/green & red/black (colour-blind issues).
    • Space: generous margins, paragraph spacing, white space.
    • Font: large enough, consistent family.
    • CAPS = shouting.
    • Repetition of shapes/colours builds cohesion.
    • Graphics attract but should not clutter.
  • Sections
    • Improve readability, navigation, and create white space.
  • Content Selection
    • Limited space → prioritise audience triggers & assignment goals.
  • Referencing
    • Use APA in-text citations + reference list.
    • URLs alone are insufficient.

Milk: Definition, Composition, & Properties

  • Physical definition
    • A solution (lactose), colloidal dispersion (proteins) & emulsion (fat globules) from mammals.
  • Natural transformations
    • Cream rise → butter after agitation.
    • Spontaneous fermentation → yogurt; draining → curd & whey.
    • Further salting/aging → cheese.
  • Compositional variability factors
    • Species, breed, season, feed, milking time, animal age/health.
  • Major constituents
    • Carbohydrate: lactose (disaccharide of galactose + glucose)
    • Sweetness \approx \tfrac15 of sucrose.
    • Poor solubility → crystalline defects in ice-cream.
    • Fermentation by Lactobacilli → lactic acid ↓pH → souring & pathogen suppression.
    • Fat (milk-/butter-fat)
    • Short-chain saturated FAs (butyric, caproic).
    • Carries fat-soluble vitamins A, D, E, K.
    • Globules stabilized by phospholipids/proteins; membrane protects vs lipase rancidity.
    • Proteins
    • \approx 82\% casein (micelles held by \text{Ca}^{2+}) ; 18\% whey.
    • Casein coagulates at \text{pH}\,4.6-4.7 or by chymosin (optimum 40\,^{\circ}\text{C}).
    • Whey denatures with heat \ge 66\,^{\circ}\text{C}; forms skin/scorch.
    • Minor: vitamins, minerals (notably Ca, P), enzymes, cells.
  • Sensory traits
    • Colour: light scattering by casein; carotene → yellow; riboflavin → greenish whey; skim looks blue.
    • Flavour: lactose sweetness, short-chain FA aroma, feed influences.
    • Acidity: fresh \text{pH}\,6.5; increases on storage.

Milk Processing Technologies

  • Pasteurisation
    • LTLT 62\,^{\circ}\text{C} / 30 min.
    • HTST 72\,^{\circ}\text{C} / 15 s.
    • UHT 138\,^{\circ}\text{C} / 2 s → shelf-stable.
  • Homogenisation
    • High-pressure through orifices ↓globule size, ↑opacity & viscosity, prevents cream separation.
  • Market types
    • Whole ( 3.25\% MF ), 2\%, 1\%, skim <0.5\%.
    • Evaporated ( -60\% water, sterilised, Maillard browning).
    • Sweetened condensed ( -50\% water + \approx55\% sugar; preservation by osmotic pressure).
    • Powdered ( 2-3\% moisture, mostly low-fat to avoid rancidity).
    • Cultured: buttermilk, yogurt, sour cream, acidophilus milk.
  • Heat & cold applications
    • Ice-cream: semi-solid foam of ice, fat, air; sugar depresses FP; churning adds air; refreeze → coarse crystals.
    • Cooking: skin/scorch due to whey & lactose; double boiler mitigates; acids/salts/old milk → curdling.
    • Foams: best at 70\,^{\circ}\text{C}; skim foams easiest; full-fat richer mouthfeel.

Milk Nutrition & Health

  • Rich source of protein, Ca, P, riboflavin, vitamins A & D.
  • Limitations: low Fe & Vit C; whole milk high in saturated fat.
  • Infant caution: cow milk unsuitable < 1 year, risk of allergy.
  • Lactose intolerance: lactase decline after age 2-5; symptoms bloating, diarrhea, gas; tolerance varies.

Plant-Based Beverages

  • Not true “milks”; produced via soaking, grinding, filtering, fortifying.
  • Common bases: soy, almond, oat, rice, cashew, coconut.
  • Processing: slurry heating (enzyme inactivation), filtration (remove insolubles & oligosaccharides), homogenise, UHT or refrigerated.
  • Nutritional comparison (per 250\,\text{ml})
    • Calories 35-67\% of dairy.
    • Protein 0-7\,\text{g} (only soy ≈ 9\,\text{g} & complete AA profile).
    • Ca 20-25\% RDA if fortified; check label.
    • B_{12} must be fortified.
  • Culinary notes
    • Baking tolerant; sauces may separate (add cornstarch, add late).
    • Coconut milk high fat (saturated); oat milk froths best.
  • Environmental footprint: dairy land use \times9 vs plant milks; almonds high water; rice → methane; soy/oat risk deforestation.

Legumes: Structure, Nutrition, Cooking

  • Terminology
    • Legume = plant; Pulse = dried seed; Bean = individual species.
  • Nutrients (per 300\,\text{g} cooked): 340-400\,\text{kcal}, 20-34\,\text{g} protein, 10-20\,\text{g} fibre, low fat (soy \approx18\,\text{g}).
  • Protein quality: limited in methionine/tryptophan; complementary with cereals (rice+beans).
  • Nitrogen fixation: root nodules → high protein.
  • Deterrents & solutions
    • Long soak/cook → use canned, pressure cooker, quick-soak ( 2 min boil + 1 h).
    • Flatulence (oligosaccharides) → soak & discard water, longer cook, fermentation, enzymes (Beano).
    • Anti-nutrients (phytates/lectins) destroyed by soaking & heat.
  • Hydration ratio water:bean 4:1; avoid salt & hard water during soak.
  • Cooking interactions
    • Alkali (baking soda) shortens cook but destroys B_{1}.
    • Acid/molasses/calcium toughen; add after softening.

Nuts & Seeds: Structure, Nutrition, Handling

  • Botanical variance (true nuts vs seeds) but culinary similarities.
  • Composition: 50-65\% oil (macadamia \approx75\%, coconut <5\%), 10-25\% protein, fibre, Vit E & folate.
  • Oil profile: mostly mono- & poly-unsaturated; coconut & palm high in saturated.
  • Allergies: peanuts/tree nuts common ( 1-2\% of population; anaphylaxis risk).
  • Flavour intensified by roasting (Maillard); nuts can rancidify (oxidative) → store 2-4\,^{\circ}\text{C} or frozen, airtight, dark.
  • Applications: nut butters (continuous oil phase), nut milks (oil droplets dispersed in water), baking (structure & flavour).

Eggs: Structure, Nutrition, Cooking Applications

  • Anatomy
    • Shell (CaCO_{3}, porous, lost “bloom” post-washing).
    • Membranes (inner, outer, chalazae).
    • White ≈ 88\% water, proteins: ovalbumin 54\%, ovotransferrin 12\%, ovomucin \lt11\%.
    • Yolk ≈ 50\% water, 33\% fat, 17\% protein, emulsifiers (lecithin).
  • Nutrition per large egg: \approx75\,\text{kcal}, complete protein, fat-soluble vitamins, cholesterol \approx 186\,\text{mg}.
  • Quality changes during storage: ↑pH to 9.7, thinner white, enlarged air cell, weaker membrane.
  • Grading (Canada): A (retail), B (processing), C (further processing); sizes: Jumbo \ge70\,\text{g} … Peewee <42\,\text{g}.
  • Functional roles
    • Coagulation/structure (custards, meatloaf).
    • Emulsification (lecithin → mayonnaise).
    • Foaming/leavening (meringues, chiffon cakes).
    • Colour/flavour, binding, glazing, clarifying.
  • Coagulation temps: white 63-65^{\circ}\text{C}, yolk 65-70^{\circ}\text{C}, whole \approx73^{\circ}\text{C}.
  • Foam variables: fresh whites, room-temp, copper bowl, acid (cream of tartar) ↑stability; fat/yolk ↓foam.
  • Safety: Salmonella killed at \ge70^{\circ}\text{C} 1 min; pasteurised products for institutions; allergens mostly in ovalbumin.

Meat & Poultry: Structure, Nutrition, Processing, Cooking

  • Meat components: muscle fibres (actin/myosin), connective tissue (collagen → gelatin w/ moist heat; elastin tough), fat (marbling), bone.
  • Nutrients: 20\% protein, vitamins B, Fe, Zn; fat varies by cut/species.
  • Post-mortem: rigor mortis; aging 14-21 d ↑tenderness via enzymes.
  • Tenderising methods: mechanical (grind, cube), enzymes (papain, bromelain), marinades (acid), moist heat.
  • Cooking principles
    • Dry heat for tender cuts (rib, loin): roast 150-175^{\circ}\text{C}, grill, pan-broil.
    • Moist heat for tough cuts (chuck, brisket, shank): braise, stew, pressure cook.
    • Internal temps (safe): beef medium \ge71^{\circ}\text{C}, ground meats 74^{\circ}\text{C}, poultry 74^{\circ}\text{C}.
    • Carry-over rise 5-10^{\circ}\text{C}.
  • Storage: refrigerate \le4^{\circ}\text{C}, use ground/organ meats \le2 d; freeze -18^{\circ}\text{C}.
  • Poultry specifics
    • Classes: broiler 1-1.3\,\text{kg}, roaster >2\,\text{kg}, stewing hen (older).
    • Dark vs white meat fat %, myoglobin content.
    • Cook to 74^{\circ}\text{C}; avoid stuffing in large birds.

Seafood: Structure, Nutrition, Processing, Cooking

  • Finfish: lean
  • Shellfish: molluscs (bivalves, cephalopods) & crustaceans; sweeter due to glycogen.
  • Low connective tissue → quick cooking; overheat → tough/dry.
  • Forms: whole, drawn, dressed, steaks, fillets, surimi.
  • Spoilage rapid; store 0^{\circ}\text{C}, cook within 48 h.
  • Safe internal temp 63^{\circ}\text{C} but many preparations (sushi, ceviche) rely on parasite-free sourcing & freezing protocols.

Alternative Proteins: Game, Insects, Cereals

  • Game meats: venison, elk, rabbit, wild fowl; usually lean, ↓saturated fat, stronger flavour; in Canada commercial ops must source from licensed farms.
  • Insect protein (entomophagy)
    • >2000 edible species; high protein, fibre, micronutrients; low land/water use.
    • Products: whole roasted, flours (cricket), bars, pasta.
  • High-protein grains: quinoa, kamut, teff, wild rice; combine with legumes/nuts for complete amino acid profile.
  • Plant-based meat analogues (e.g. “Impossible”/“Beyond”)
    • Ultra-processed; use soy/pea protein, heme analogues; often high Na and added fats; check labels.

Fats & Oils: Chemistry, Processing, Culinary Uses

  • Triglyceride basics
    • Glycerol + 3 FA; saturated vs unsaturated; cis vs trans.
  • Physical properties
    • Melting point ↑ with saturation & chain length.
    • Plasticity: ability to be shaped/creamed.
    • Smoke point: onset of continuous smoke; refined oils > 220^{\circ}\text{C}.
  • Processing
    • Extraction (pressing, solvent), refining (degum, bleach, deodorise), hydrogenation (adds H, creates trans; now limited), winterization (remove high-melting FAs).
  • Common fats
    • Butter \ge80\% fat water-in-oil emulsion.
    • Margarine (vegetable oil + milk solids + emulsifiers) \ge80\% fat.
    • Lard (rendered pork fat) plastic but prone to rancidity.
    • Shortening (hydrogenated blend) high smoke point.
    • Culinary oils: olive (high MUFA), canola (high MUFA/\omega3), peanut (frying), coconut/palm (saturated, low smoke).
  • Rancidity
    • Oxidative (O_2 + unsaturated FA → hydroperoxides → off-flavour); accelerated by heat, light, metals; prevented by antioxidants (BHA/BHT, Vit E) & cool dark storage.
    • Hydrolytic (lipase + moisture).
    • Reversion (early off-flavour in linoleic oils).

Deep-Fat Frying

  • Ideal frying range 177-191^{\circ}\text{C} ( 350-375^{\circ}\text{F}).
  • High smoke-point neutral oil; low free FA; minimal emulsifiers.
  • Quality indicators: golden colour, crisp surface, minimal fat uptake.
  • Oil care: filter daily, maintain temp, avoid water/salt, replace when dark, viscous, foamy, smoke point drops.
  • Safety: never add wet food; smother grease fires (lid, \mathrm{NaHCO}_3); no water.

Emulsions, Foams, Salad Dressings

  • Dispersed vs continuous phase; require emulsifiers (lecithin, proteins, gums).
  • Types
    • Oil-in-water: milk, cream, mayonnaise ( \ge65\% oil, vinegar/lemon, egg yolk emulsifier).
    • Water-in-oil: butter, margarine.
  • Stability factors: droplet size ↓, viscosity ↑, adequate emulsifier, proper phase ratio.
  • Foams: gas dispersed in liquid (egg white, whipped cream).
    • Need low surface tension; proteins form elastic film.
    • Over-beating → dry, curdled.
  • Salad dressings
    • French/vinaigrette (temporary emulsion): \approx 3:1 oil:vinegar.
    • Cooked/starch-thickened dressings.
    • Breakage cures: start new yolk/water, slowly whisk in separated mix.