LC Home Economics cheat sheet

Maillard browning begins around 140-165°C and requires a reducing sugar plus an amino group; it is distinct from caramelisation, which needs sugar alone.

Gluten forms when glutenin (elasticity) and gliadin (extensibility) hydrate and are worked; fat and sugar shorten gluten strands by limiting hydration.

Gelatinisation: starch granules absorb water, swell and rupture on heating (about 60-95°C depending on starch), thickening the liquid; cooling sets a gel.

Retrogradation is the re-crystallisation of cooled starch gels, causing staling and syneresis (weeping); reheating reverses it temporarily.

Emulsions: oil-in-water (milk, mayonnaise) needs an emulsifier with both hydrophilic and lipophilic ends; lecithin in egg yolk is the classic example.

Collagen converts to gelatin with moist heat over long periods (roughly 70-80°C+); dry high heat instead toughens and shrinks muscle fibres.

Cross-contamination control: separate boards for raw meat and ready-to-eat food; the danger zone is 5-63°C, with bacteria multiplying fastest near 37°C.

Enzymatic browning (polyphenol oxidase) darkens cut fruit and vegetables; acid, blanching or excluding oxygen slows it.

Energy values: carbohydrate 4 kcal/g, protein 4 kcal/g, fat 9 kcal/g, alcohol 7 kcal/g; fibre is often counted at about 2 kcal/g.

Macronutrient energy contribution is calculated as (g nutrient × kcal/g) ÷ total kcal × 100; the three percentages must sum to 100.

Protein needs rise in pregnancy, lactation, growth and recovery from illness; protein is not a primary fuel unless intake is excessive or carbohydrate is very low.

Fat-soluble vitamins A, D, E and K require dietary fat for absorption and are stored in the liver and adipose tissue; water-soluble vitamins are excreted more readily.

Iron: haem iron from meat is absorbed more efficiently than non-haem iron from plants; vitamin C enhances non-haem absorption, while tannins and phytates inhibit it.

Calcium absorption depends on vitamin D; deficiency risks rickets in children and osteoporosis in later life.

BMI = weight (kg) ÷ height (m)²; adult categories: under 18.5, healthy 18.5-24.9, overweight 25-29.9, obese 30 and above.

Basal metabolic rate is driven mainly by lean body mass, age and sex; total energy expenditure adds activity and the thermic effect of food.

Resources are classified as human (energy, time, skills, knowledge) and non-human (money, equipment, space); management matches resources to goals.

The management process: identify need, set goals, plan, implement, evaluate; feedback from evaluation re-enters the planning stage.

Opportunity cost is the value of the best alternative forgone when a choice is made; every purchase has one.

SMART goals are Specific, Measurable, Achievable, Relevant and Time-bound; vague goals cannot be evaluated.

Budget formula: income − fixed expenditure − variable expenditure = surplus or deficit; fixed costs (rent) do not vary with usage.

Unit price = total price ÷ quantity; comparing unit prices is the reliable way to judge value across different pack sizes.

Consumer protection typically covers the right to safety, information, choice, redress and representation; a receipt is the main evidence for redress.

Planned obsolescence shortens product life by design; comparing durability, warranty length and running costs reduces long-term expenditure.

Family life cycle stages: beginning, expanding, contracting, launching and ageing; needs and expenditure patterns shift at each stage.

Functions of the family: reproduction, socialisation, economic provision, emotional support and care of dependants.

Role conflict arises when demands of two roles clash; role overload arises when total demands exceed time and energy.

Dual-earner families reallocate domestic labour; inequality in sharing housework is a recognised source of family stress.

Demographic trends such as falling birth rates and ageing populations raise dependency ratios and shift demand toward health and care services.

Socialisation is primary (within the family, early) and secondary (school, peers, media); both transmit norms, values and skills.

Conflict resolution strategies: avoidance, accommodation, compromise, collaboration and competition; collaboration seeks a win-win outcome.

Family income sources include wages, welfare transfers and asset income; disposable income is income after tax and mandatory deductions.

Fibres are natural (cotton, wool, silk, linen) or manufactured (regenerated such as viscose, and synthetic such as polyester, nylon, acrylic).

Staple fibres are short and spun into yarn, giving warmth and absorbency; filament fibres are continuous, giving smoothness and strength.

Wool felts and shrinks because of overlapping scales plus moisture, heat and friction; cotton shrinks mainly through relaxation of tension during washing.

Plain weave is strong and firm; twill has diagonal ridges and drapes well; satin has long floats giving lustre but low abrasion resistance.

Knitted fabrics stretch because loops allow movement; woven fabrics are more dimensionally stable.

The design process: brief, research, specification, ideas, development, prototype, testing, evaluation; the specification sets measurable criteria.

Colour schemes: monochromatic (one hue), analogous (adjacent hues), complementary (opposite hues), triad (three evenly spaced hues).

Care labelling symbols convey washing temperature, bleaching, drying, ironing and dry-cleaning instructions; fibre content must be stated on the label.

Sensory testing: paired comparison, triangle test and ranking are discrimination tests; hedonic scales measure preference rather than difference.

Standard recipe costing: ingredient cost ÷ number of portions gives cost per portion; add overheads and a mark-up to set selling price.

Blanching vegetables inactivates enzymes before freezing, preserving colour, flavour and texture during storage.

Carry-over cooking continues after food leaves the heat; resting meat allows juices to redistribute and improves tenderness.

Dietary reference values distinguish RNI (meets the needs of nearly all), EAR (average requirement) and LRNI (adequate for only a few).

Glycaemic index ranks carbohydrate foods by blood glucose response; low-GI foods slow glucose release and aid satiety.

Saturated fat raises LDL cholesterol more than unsaturated fat; trans fats raise LDL and lower HDL.

Sodium intake above requirements is linked to raised blood pressure; processed foods are the main dietary source.

Food allergies involve an immune response (e.g. peanuts, shellfish); intolerances (e.g. lactose) are non-immune and dose-related.

Needs are essential for survival or functioning; wants improve comfort or status and are shaped by culture, peers and advertising.

Value for money weighs cost against quality, durability and after-sales service, not price alone.

Depreciation reduces asset value over time; resale value is highest for well-maintained, durable goods.

Credit costs more than the ticket price once interest and fees are added; annual percentage rate allows comparison across lenders.

Time management tools: prioritising (urgent versus important), scheduling and delegating; time is a finite, non-renewable resource.

Decision-making steps: define the problem, gather information, list alternatives, weigh consequences, decide, act and review.

Changing family structures include single-parent, blended, extended and same-sex-parent families; each alters resource demands.

Work-life balance is affected by commuting, shift patterns and childcare availability, not only by hours worked.

Seam allowance is the fabric between the stitching line and the raw edge, commonly 1.5 cm; a French seam encloses raw edges for sheer or washable fabrics.

Grain line: lengthwise grain is least stretchy and should run vertically for stability; bias grain has the most stretch and best drape.

Pattern symbols include notches, darts, fold lines and grain arrows; transferring them accurately prevents distortion at assembly.

Fastenings: zips give secure closure, buttons allow adjustment, hook-and-loop is quick but less durable for heavy wear.

Sustainability in textiles: choose natural or recycled fibres, reduce overproduction, extend garment life through repair and design for disassembly.