Culinary practice and menu planning: recipe development, nutrient calculation and meal design
Domain 5 is the applied domain: you take raw ingredients, account for what cooking does to weight and nutrients, and end with a portion that meets a defined target group's needs. Marks are lost when raw weights are treated as served weights.
Standardised recipes and yield factors
- Yield factor = cooked weight ÷ raw weight. Meat loses 25–30 % during roasting, vegetables 5–15 %; frying adds 5–10 % fat, roughly 40 kcal per 5 g.
- Peeled and trimmed weight differs from purchased weight: with 12 % peeling loss, 4.8 kg net potato needs 4.8/0.88 = 5.45 kg gross.
- Fix portion sizes, seasoning and cooking method in the recipe so nutrient calculation is reproducible.
Nutrient retention
Vitamin C is heat-, oxygen- and light-sensitive: losses reach 50 % in prolonged cooking, plus leaching into the cooking water. Practical consequences: short cooking times, little water, steam or microwave, cutting shortly before cooking, lids on pans, avoiding long warm holding. Fat-soluble vitamins are more stable but can migrate into frying fat.
Meal design rules
A main meal should cover roughly one third of daily reference values. DGE guidance: 400 g fruit and vegetables a day ("5 a day"), wholegrain products, 2–3 meat portions (300–600 g) per week, fish once or twice a week, maximum 6 g salt per day, and at least 30 g fibre. Design also means contrast in colour, texture and temperature, seasonal and regional sourcing, allergen transparency and a menu cycle of several weeks to avoid repetition.
Worked example
A recipe for four portions uses 800 g potatoes, 400 g leeks and 40 g butter. Scaling to 60 portions means a factor of 15: 12 kg potatoes, 6 kg leeks, 600 g butter. If the potatoes are peeled with 12 % loss, purchase 13.6 kg. Energy check per portion: 200 g boiled potato ≈ 140 kcal, 100 g leeks ≈ 25 kcal, 10 g butter ≈ 75 kcal, total ≈ 240 kcal with about 9 g fat (34 % of energy). Reducing butter to 5 g per portion gives 205 kcal and 25 % fat energy - a better fit to the 30 % guideline, achieved by a change in the recipe rather than in the portion size.
Traps
- Calculating nutrients from raw weights when the dish is served cooked.
- Forgetting the fat used for frying, which can double the fat content of vegetables.
- Ignoring allergen cross-contact in the workflow.
- Citing a portion size without stating raw or cooked weight.