MATSEC AM Home Economics and Human Ecology cheat sheet

Macronutrient energy values: carbohydrate 4 kcal/g (17 kJ/g), protein 4 kcal/g (17 kJ/g), fat 9 kcal/g (37 kJ/g), alcohol 7 kcal/g (29 kJ/g).

DRV for energy from fat: no more than 35% of daily energy; saturated fat no more than 11% of energy (UK COMA/SACN).

Protein RNI for adults: 0.75 g per kg body weight per day; energy contribution typically 10–15%.

Carbohydrate intake: at least 50% of energy from total carbohydrate; free sugars no more than 5% of energy (SACN 2015).

Fibre recommendation (UK): 30 g per day for adults (AOAC fibre method); children lower by age.

Salt: maximum 6 g/day for adults; 2–3 g for children 4–6; 5 g for 7–10; 6 g for 11+.

BMI formula: weight (kg) / height (m)^2; adult categories: <18.5 underweight, 18.5–24.9 healthy, 25–29.9 overweight, ≥30 obese.

Fat-soluble vitamins A, D, E, K are stored in liver/adipose; water-soluble B and C are not stored and excess is excreted.

Vitamin D: 10 µg (400 IU) daily for all adults and children over 1 year (UK 2016 recommendation).

Maillard reaction: reducing sugar + amino acid + heat (>140°C) gives brown colour and flavour compounds; requires moisture below ~15% for browning.

Caramelisation: sugar heated alone above melting point (~160°C) produces brown colour and caramel flavour; no protein needed.

Gelatinisation: starch granules absorb water and swell when heated in liquid; gelatinisation temperature typically 60–80°C depending on starch type.

Denaturation: heat, acid or mechanical action alters protein tertiary structure without breaking peptide bonds; example egg white coagulates at ~60–65°C.

Emulsion: dispersion of one liquid in another; oil-in-water (mayonnaise) stabilised by lecithin from egg yolk; water-in-oil (butter) stabilised by fat crystals.

Shortening: fat coats flour particles, limiting gluten development and producing crumbly texture (shortcrust pastry).

Fermentation: yeast converts sugars to ethanol and CO2; optimum temperature 25–30°C; salt inhibits competing microbes.

Enzymatic browning: polyphenol oxidase acts on cut fruit/vegetables in presence of oxygen; inhibited by acid (lemon juice), heat (blanching) or exclusion of oxygen.

Danger zone for bacterial growth: 5–63°C; keep high-risk foods out of this range; refrigeration at 0–5°C, freezer at -18°C or below.

Bacterial growth phases: lag, log (exponential), stationary, death; most food poisoning bacteria multiply fastest at 37°C.

High-risk foods: moist, protein-rich foods (meat, poultry, dairy, eggs, cooked rice, shellfish); low-risk: dry, acidic or high-sugar foods.

Preservation principles: remove moisture (drying, salting, sugaring), lower pH (pickling, fermentation), heat (canning, pasteurisation), cold (chilling, freezing), exclude oxygen (vacuum packing).

Pasteurisation: 72°C for 15 seconds (HTST) or 63°C for 30 minutes (LTLT) for milk; kills pathogens but not all spoilage organisms; product must be refrigerated.

Sterilisation/canning: 121°C for 15 minutes (retort) to destroy Clostridium botulinum spores; low-acid canned foods require pressure canning.

Freezing does not kill microorganisms; it stops growth; thaw in refrigerator, never at room temperature, to limit pathogen multiplication.

HACCP: seven principles - hazard analysis, CCP identification, critical limits, monitoring, corrective actions, verification, record keeping.

Cross-contamination control: separate raw and ready-to-eat foods; colour-coded chopping boards; wash hands after handling raw meat.

Pregnancy: additional energy ~200 kcal/day in third trimester; folic acid 400 µg/day pre-conception and first 12 weeks; avoid alcohol, limit caffeine to 200 mg/day.

Lactation: energy cost ~500 kcal/day; iron absorption enhanced; continue vitamin D 10 µg/day.

Infancy: exclusive breastfeeding for first 6 months; introduce solids from 6 months; avoid honey before 12 months (botulism risk); whole cow's milk not as main drink before 12 months.

Weaning: iron-rich foods first (fortified cereal, pureed meat, pulses); introduce allergen foods from 6 months; no added salt or sugar.

Childhood: growth charts (UK-WHO) used to monitor weight and height; obesity defined as BMI ≥ 95th centile for age.

Adolescence: peak bone mass acquisition; calcium RNI 11–18 years: 1000–1300 mg/day; iron needs higher in girls due to menstruation.

Adulthood: sarcopenia (loss of muscle mass) begins ~30 years; protein needs may increase to 1.0–1.2 g/kg in older adults.

Older adults: vitamin D 10 µg/day; hydration risk due to reduced thirst; risk of malnutrition (MUST screening tool).

Erikson's psychosocial stages: trust vs mistrust (infancy), autonomy vs shame (toddler), initiative vs guilt (preschool), industry vs inferiority (school age), identity vs role confusion (adolescence).

Family life cycle stages: beginning (newly married), expanding (children), contracting (children leave), ageing (retirement).

Resource management process: planning, implementing, evaluating; resources classified as human (time, energy, skills) and non-human (money, equipment, space).

Budget types: balanced (income = expenditure), surplus (income > expenditure), deficit (expenditure > income).

Fixed expenses (rent, insurance) do not vary with usage; variable expenses (food, utilities) fluctuate; irregular expenses (car repairs) require sinking funds.

Opportunity cost: the value of the next best alternative foregone when a resource is allocated to one use.

Time management tools: priority matrix (urgent/important), Gantt chart, to-do lists; work simplification (e.g., batch cooking) reduces energy expenditure.

Decision-making model: identify problem, gather information, list alternatives, weigh consequences, choose, implement, evaluate.

Consumer credit: APR (annual percentage rate) expresses true cost of borrowing; compare APR not just monthly payments.

Natural fibres: cotton (cellulose, absorbent, strong when wet), wool (protein, warm, felts), silk (protein, lustrous, strong), linen (cellulose, cool, creases).

Regenerated fibres: viscose/rayon from wood pulp; lyocell (Tencel) from eucalyptus with closed-loop solvent recovery.

Synthetic fibres: polyester (petroleum-based, strong, hydrophobic, quick-drying), nylon (polyamide, very strong, elastic), acrylic (wool-like, warm).

Fabric construction: woven (warp and weft, stable), knitted (loops, stretchy), non-woven (bonded fibres, no grain).

Care labelling: wash tub symbol with number = maximum temperature; triangle = bleaching allowed; square = tumble drying; iron = temperature dots; circle = dry cleaning.

Colour fastness: resistance to washing, light, rubbing (crocking); test with a small sample before washing.

Consumer rights (Malta): Consumer Affairs Act; right to redress for faulty goods; two-year legal guarantee for conformity.

Eco-labels for textiles: OEKO-TEX Standard 100 (harmful substances tested), GOTS (organic cotton), EU Ecolabel.

Housing needs: shelter, security, privacy, space for activities, adequate lighting, ventilation, thermal comfort.

Ventilation: recommended air changes per hour (ACH): living rooms 1–2 ACH; kitchens 6–10 ACH; bathrooms 6–10 ACH.

Thermal comfort: indoor temperature 18–21°C living areas; relative humidity 40–60% to avoid condensation and mould.

Condensation control: increase ventilation, insulate cold surfaces, avoid drying clothes indoors without ventilation, use extractor fans.

Ergonomics: kitchen work triangle (sink, hob, fridge) with each leg 1.2–2.7 m; worktop height 85–90 cm.

Universal design: seven principles including equitable use, flexibility, simple intuitive use, perceptible information, tolerance for error, low physical effort, size and space for approach and use.

Housing tenure types: owner-occupied, private rented, social housing; Malta has rent laws under the Housing Authority.

Sustainable home features: double glazing, loft insulation, solar water heating, rainwater harvesting, low-flow taps, LED lighting.

WHO definition of health: a state of complete physical, mental and social well-being, not merely absence of disease.

Determinants of health: biological, behavioural, physical environment, social and economic (income, education, employment), and access to healthcare.

Public health measures: vaccination, screening, health education, food fortification (e.g., folic acid in flour), fluoridation.

Mental health: stress management, sleep hygiene (7–9 hours adults), social connection; stigma reduction through education.

Community resources: local health centres, social services, voluntary organisations, food banks, parent support groups.

Health inequalities: gap in health status between socio-economic groups; addressed by targeted interventions (e.g., Healthy Start vouchers).

Physical activity guidelines (WHO): 150–300 minutes moderate or 75–150 minutes vigorous per week for adults; muscle strengthening twice weekly.

Food security: reliable access to sufficient, safe, nutritious food; household food insecurity measured by USDA 18-item module.

Investigation design: aim, hypothesis, variables (independent, dependent, controlled), method, risk assessment, results, conclusion, evaluation.

Sensory evaluation: difference tests (triangle, paired comparison) and preference tests (hedonic scale 1–9); panelists must not be influenced by labels.

Accurate measurement: use digital scales (0.1 g), measuring jugs at eye level, calibrated thermometers; repeat measurements to reduce error.

Fair test: change only one variable; keep all others constant; use a control group where appropriate.

Risk assessment: identify hazard, who may be harmed, likelihood and severity, control measures, review.

Recording data: tables with units, averages, range; graphs with labelled axes; calculate percentages and means.

Evaluation: discuss reliability (repeat readings), validity (does test measure what it claims?), and sources of error (human, instrumental, environmental).

Food practical skills: knife safety (claw grip), safe use of hob/oven, temperature probe for cooked meat (75°C), cooling food quickly within 90 minutes.