Food Products and Value Addition (Cereals, Pulses, Dairy, Fruits, Vegetables)
This domain tests how raw commodities become stable, saleable products: milling and parboiling of cereals, dal milling, dairy processing, and fruit and vegetable products such as jam, jelly, squash and tomato products.
Core rules and concepts
- Cereals: cleaning, grading, parboiling, milling and polishing. Parboiling gelatinizes starch and improves milling recovery; over-polishing loses vitamins.
- Pulses: dal milling splits and dehulls grain; conditioning improves yield and reduces breakage.
- Dairy: pasteurization, cream separation, homogenization, fermentation and concentration. Casein precipitates at its isoelectric point, around pH 4.6.
- Jam, jelly and marmalade rely on sugar, acid and pectin. A typical jam target is about 68°Brix total soluble solids and pH around 3.0-3.5 for gel and preservation.
- Vegetables and fruits: minimal processing, blanching, canning, drying, freezing and value-added products such as pickles, chutneys and juices.
- Value addition improves shelf life, convenience and margin, but adds costs for packaging, testing and compliance.
Worked example
One kilogram of fruit pulp at 10% total soluble solids is mixed with 1 kg sugar. Solids are 100 g + 1000 g = 1100 g in 2000 g total, or 55°Brix. To reach 68°Brix, total mass must be 1100/0.68 = about 1618 g, so about 382 g of water must be evaporated, followed by pectin and acid adjustment.
Traps that cost marks
- Jam and jelly are not identical; jelly is made from clear fruit extract.
- Pectin needs both acid and sugar to gel.
- Over-boiling darkens colour and damages flavour.
- Parboiling is not the same as simple washing.
- A high sugar level alone does not guarantee safety if hygiene is poor.