Describe the process of canning fruits and vegetables.
How to lay out the answer. Follow the frame, then write it in your own words.
1 · Open in two lines. Canning preserves food by sealing it in airtight containers and heating it to destroy spoilage and disease organisms. Nicolas Appert developed it.
2 · Preparation.
Select, grade and wash the produce.
Peel, core and cut; blanch vegetables.
3 · Filling, syruping or brining, exhausting.
Fill lacquered cans, leaving headspace.
Hot syrup for fruits, dilute brine for vegetables.
Exhaust by heat or vacuum to remove air.
4 · Draw the flow chart. [Flow: select → wash → peel/cut → blanch → fill → syrup/brine → exhaust → seal → process → cool → label → store]
5 · Sealing and processing.
Double-seam the lid.
Acid fruits (pH below 4.5): boiling water, 100 °C.
Low-acid vegetables: retort at about 121 °C; 12D botulinum cook.
6 · Cooling, labelling, storage. Cool quickly to about 35-40 °C, dry, label and store cool; reject swells and leakers.
7 · Nutrition link. Canned foods keep protein and minerals; some vitamin C and thiamine are lost. Never use swollen cans: botulism risk.
8 · Close in one line. Correct exhausting, sealing and heat processing give safe food that keeps for a long time.
Scoring tip: A flow chart, one line of purpose for each step, and the 100 °C vs 121 °C rule score full marks.
