Food science and food technology: composition, processing, additives and food law basics
Domain 2 asks what a food is made of, what processing does to it, which additives are permitted, and which legal framework governs the product. Tasks often require you to explain a process reaction and then apply a labelling or additive rule to a concrete product.
Composition and analysis
Water content and water activity (aw) determine microbial stability more than total water does; lowering aw by drying, salting or sugaring is a hurdle technology. Salt on a label is calculated as sodium × 2.5, so 0.4 g sodium per 100 g equals 1.0 g salt.
Process reactions you must be able to explain
- Maillard reaction: reducing sugar plus amino group, browning and aroma from about 140 °C, with acrylamide as an undesired by-product in potato and cereal products; mitigation by blanching, lower frying temperature, asparaginase.
- Caramelisation: sugars alone, no amino groups.
- Starch gelatinisation at roughly 60–70 °C; retrogradation explains staling of bread.
- Protein denaturation by heat, acid or shear (egg coagulation around 70–80 °C).
- Fat oxidation and rancidity; antioxidants (E 300–399) delay it.
- Preservation: chilling 0–4 °C, pasteurisation 72 °C/15 s, UHT 135–150 °C for a few seconds, sterilisation at F0 ≥ 3 min (reference 121 °C).
Additives
Regulation (EC) 1333/2008 permits only additives that are technologically justified and safe; EFSA derives an ADI, e.g. 40 mg/kg body weight per day for aspartame. Additives appear in the ingredient list by functional class plus name or E number.
Food law basics
Regulation (EC) 178/2002 sets general principles, traceability one step back and one step forward, the RASFF alert system and operator responsibility. Reg. 1169/2011 governs consumer information, 1924/2006 nutrition and health claims, 2018/848 organic production. Hygiene law sits in 852/2004 and 853/2004.
Worked example
A yoghurt per 100 g: 4.0 g protein, 3.5 g fat, 12 g carbohydrate (of which sugars 11 g), salt 0.12 g. Energy = 16 + 31.5 + 48 = 95.5, i.e. 96 kcal (rounded to the nearest 1 kcal). A 150 g pot therefore carries 1.5 × 96 = 144 kcal. The claim "low fat" is not permitted because 3.5 g/100 g exceeds the 3 g/100 g threshold, although "source of protein" would be defensible at 4 g/100 g.
Traps
- Confusing "no added sugar" (legal even with natural sugars) with "sugar-free" (≤0.5 g/100 g).
- Assuming "light" is a regulated term - under EU law it has no nutrient-claim definition.
- Forgetting QUID (quantitative ingredient declaration) for ingredients named on the pack.
- Treating pasteurisation and sterilisation as interchangeable.