Processing of Fruits, Vegetables and Beverages
7. Processing of Fruits, Vegetables and Beverages
This domain tests preservation and value addition for perishable produce: juices, pulps, jams, jellies, squashes, canned vegetables, dehydrated products and beverages. Standards for TSS, acidity and preservatives are common exam targets.
Core rules
- Juice is extracted by pressing/pulping, then clarified or left cloudy; pulp retains insoluble solids.
- Jam uses pulp, sugar, acid and pectin; jelly uses clear juice; marmalade uses citrus peel and pulp.
- Squash and cordial are diluted beverages preserved by sugar, acid and permitted preservative; ready-to-drink beverages are usually pasteurised or hot-filled.
- Blanching vegetables before freezing/drying inactivates enzymes; sulphiting controls browning but is restricted.
- Low-acid vegetables need pressure canning or acidification; high-acid fruits can be hot-filled.
- Beverages include carbonated drinks, fruit drinks, tea/coffee and dairy-based drinks; each has different processing and labelling rules.
Worked example
100 kg mango pulp at 12°Brix is used to make nectar at 15°Brix. Let x kg sugar be added: (12 + x)/(100 + x) = 0.15. 12 + x = 15 + 0.15x; 0.85x = 3; x = 3.53 kg. Final mass ≈ 103.5 kg. Reasoning: Brix is a mass fraction of soluble solids; sugar adds solids and mass.
Traps
Jam, jelly and marmalade are not interchangeable. A low-acid vegetable canned without pressure processing risks botulism. Ascorbic acid controls browning but is not a preservative at low levels. Do not ignore FSSAI limits for preservatives.