Food Preparation and Cooking Principles, Techniques and Equipment
What this domain tests
This domain tests cooking methods, the science behind food changes, safe use of equipment and nutrient retention. Expect questions comparing methods, explaining browning or coagulation, and choosing equipment for a task.
Core rules and concepts
- Heat transfer occurs by conduction (direct contact), convection (moving air or liquid) and radiation (grill or open fire).
- Moist methods include boiling, steaming, poaching and stewing; dry methods include baking, roasting, grilling and frying. Frying uses hot fat as the heat-transfer medium.
- Key changes: protein coagulates and toughens with overcooking; starch gelatinises and thickens; sugars caramelise; the Maillard reaction browns proteins and sugars; emulsions stabilise mixtures of oil and water.
- Equipment must be clean, safe and fit for purpose: sharp knives, stable pots, heatproof handles, clean fuel stoves, and food-safe containers. In Cameroonian homes, mortars, grinding stones, charcoal stoves and firewood are common; ventilation and safe fuel handling matter.
- Preserve nutrients by preparing close to cooking time, using short cooking times, steaming or minimal-water cooking, leaving skins on where suitable, and using cooking liquid in soups or stews.
Worked example
Compare boiling chopped vegetables in plenty of water with steaming them. Reasoning: vitamin C and B vitamins dissolve in water and are destroyed by heat and oxygen. Boiling in excess water leaches these vitamins into water that is often discarded; steaming exposes food to less water and often a shorter cooking time, so more vitamins are retained. If boiling is necessary, use only a little water and reuse the liquid in a stew or soup. Overcooking also softens texture excessively and dulls colour.
Traps that cost marks
- High heat does not “seal in” nutrients; it can destroy heat-sensitive vitamins.
- Soaking legumes reduces cooking time but can leach water-soluble vitamins; do not discard soaking water unnecessarily.
- Adding salt early to some foods can draw out water or affect texture; follow the recipe purpose.
- Overheated oil smokes, breaks down and can form harmful compounds; do not reuse it repeatedly.
- A sharp knife is safer than a blunt one because it needs less force and is less likely to slip.