Question

The correct order of unit operations carried out in the Canning of vegetables is:

• A. Sorting----Retorting----Exhausting----Filling----Sealing
• B. Retorting---Filling----Exhausting----Processing----Sealing
• C. Retorting----Filling----Processing----Exhausting----Sealing
• D. Sorting----Filling----Exhausting----Sealing------Retorting

Hint:

For any preservation process, always think logically. Raw material preparation (Sorting) comes first. The final "kill step" or sterilization (Retorting) must happen after the container is sealed to prevent recontamination.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Canning is a method of food preservation in which food is processed and sealed in an airtight container. The process involves a series of sequential steps designed to prepare the food, package it, and then render it commercially sterile.
Step 3: Detailed Explanation:
The logical sequence of operations in vegetable canning is as follows:
1. Sorting: The process begins with the raw material. Vegetables are sorted and graded for quality, size, and maturity. (This is often preceded by washing).
2. Filling: The prepared vegetables (which may have been peeled, cut, or blanched) are filled into cans. Brine or sauce is also added.
3. Exhausting: Before sealing, air is removed from the headspace of the can. This is done to create a vacuum after cooling, which prevents internal can corrosion and minimizes oxidative spoilage.
4. Sealing: The can is immediately hermetically (airtightly) sealed.
5. Retorting: This is the final and critical step. The sealed cans are subjected to high-pressure steam (typically at 121\(^{\circ}\)C) in a retort to destroy spoilage microorganisms and their spores, achieving commercial sterility.
The order in option (D) correctly follows this sequence. The other options place the final sterilization step (Retorting) at or near the beginning, which is incorrect.
Step 4: Final Answer:
The correct sequence of unit operations is Sorting \(\rightarrow\) Filling \(\rightarrow\) Exhausting \(\rightarrow\) Sealing \(\rightarrow\) Retorting. Therefore, option (D) is correct.