Fundamentals of Food and Food Science
Fundamentals of Food and Food Science
This domain tests how food components behave before, during and after cooking: water, carbohydrates, proteins, fats, vitamins, minerals, pigments and enzymes. Expect questions on food groups, nutrient functions, and physical and chemical changes such as gelatinisation, denaturation, caramelisation and browning.
Core rules and concepts
- Carbohydrates include sugars, starches and fibre. Starch gelatinises in moist heat when granules absorb water and swell; on cooling it can gel or retrograde.
- Proteins denature through heat, acid, salt or mechanical action; denaturation changes shape, not primary sequence.
- Fats are emulsified by agents such as egg yolk lecithin; emulsification disperses one liquid in another.
- Enzymatic browning occurs when polyphenol oxidase acts on cut fruit or vegetables. Maillard browning needs a reducing sugar and an amino group under dry heat.
- Water activity, pH and temperature control microbial growth and food stability.
Worked example
A cut apple turns brown, while a sliced potato fried at high heat turns golden. Reasoning: the apple has active polyphenol oxidase and oxygen, so enzymatic browning dominates; lemon juice lowers pH and slows the enzyme. The potato's golden colour comes mainly from Maillard browning and caramelisation during frying, not from the same enzyme reaction.
Traps
Do not call gelatinisation the same as gelation: gelatinisation is swelling with heat; gelation is setting into a gel. Do not say heat destroys a protein's amino acid sequence. Maillard browning is not simply burning sugar; it requires both sugar and protein. Fibre is a carbohydrate but is not a significant energy source for humans.