Energy balance explores the relationship between food intake and physical activity, focusing on how individuals maintain a healthy body weight throughout l
Topic Synopsis
Energy balance explores the relationship between food intake and physical activity, focusing on how individuals maintain a healthy body weight throughout life. It covers the calculation of energy requirements, the sources of energy in the diet, and the factors influencing these needs.
Key Concepts & Core Principles
- Thickening methods: Understand how starch (e.g., flour, cornflour) gelatinises to thicken sauces, and the importance of cooking out raw starch to avoid a floury taste.
- Emulsification: Know how to create stable emulsions (e.g., hollandaise, mayonnaise) by slowly adding fat to a water-based liquid while whisking vigorously, and the role of emulsifiers like egg yolk.
- Roux-based sauces: Master the three stages of a roux (white, blond, brown) and how the cooking time affects flavour and colour, as well as the correct liquid-to-roux ratio (e.g., 500ml milk to 50g each of butter and flour for a pouring sauce).
- Acid and reduction: Learn how acids (e.g., lemon juice, vinegar) can balance richness and how reducing sauces (simmering to evaporate water) concentrates flavour and thickens without starch.
- Fault-finding and correction: Identify common sauce faults such as lumps (strain or blend), skin formation (cover with cling film), separation (re-emulsify with a little cold liquid), and curdling (cool and whisk vigorously).
Examiner Marking Points
- Understanding of Basal metabolic rate (BMR) and physical activity level (PAL) in determining energy requirements
- Ability to calculate energy values and identify main sources of energy
- Knowledge of recommended percentage of daily energy intake
- Identification of energy sources: protein, fat, carbohydrate and alcohol
- Understanding of units (kcal and kJ) for measuring energy
- Knowledge of factors influencing energy requirements: gender, life stage, pregnancy/lactation, size/body weight, genetics, occupation and lifestyle
- Understanding of the consequences of deficiency and excess