This set of Fruits Processing Multiple Choice Questions & Answers (MCQs) focuses on “Freezing Changes in Cold Storage”.
1. Which fruit undergoes the chilling injury?
a) Apple
b) Orange
c) Banana
d) Custard apple
View Answer
Explanation: Chilling injury is most common in banana. Chilling injury is the damage to the plant parts that is caused by temperatures above the freezing point. The tissue in the fruits gets damaged that leads to cellular dysfunctions.
2. Which of the following injuries is physiological injury in fruits?
a) Bruises
b) Cuts
c) Chilling injury
d) Carbon dioxide injury
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Explanation: Chilling injury affects both fruits and vegetables. Tropical and subtropical crops are sensitive to chilling injury. These crops are injured by low, but not in freezing temperatures. At these temperatures, the tissues deteriorate since they are unable to carry normal metabolic processes.
3. At what temperature does chilling injury occurs in potatoes?
a) -16.6°C
b) 0 °C
c) -1 °C
d) -2 °C
View Answer
Explanation: The temperature between -1.6 °C and 0 °C, it causes light frost. Temperature ranging from -3.6°C and -2°C causes serious damage to the potatoes. Therefore the ideal conditions for storing potatoes are well ventilated with cool temperatures. It should have high humidity and no light.
4. Chilling injury degrades the chlorophyll in the plants.
a) True
b) False
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Explanation: Chilling injury causes metabolic dysfunctions in the plant. It disrupts the conversion of starch to sugars activity. It decreases the carbon dioxide exchange. It reduces the net photosynthesis and finally degrades the chlorophyll.
5. What are the sources of freezing injury?
a) Freezing of soil water
b) Freezing of the fluids within the plant
c) Freezing of leaves
d) Freezing of the fluids within the plant and freezing of soil water
View Answer
Explanation: The soil water available to the plants is found in the permeable areas between the soil particles. It normally freezes at -2°C. This deprives the plant from its source of water. Freezing of water within the plant causes disruption of the structure and function of cells and tissues. Ice forms first in the cell walls and intercellular spaces. Actual damage occurs when ice crystals develop and rupture into the cytoplasm.
6. What is vitrification?
a) Solidification of the cellular content into non-crystalline state
b) Sublimation of the cellular content into non-crystalline state
c) Solidification of the non-crystalline into cellular content
d) Sublimation of the non-crystalline into cellular content
View Answer
Explanation: Vitrification is defined as the Solidification of the cellular content into non-crystalline state that is into the amorphous state. It occurs by rapid freezing of cells to a very low temperature. Vitrification is accountable for its impenetrability to water. It is the rapid cooling of liquid in the absence of ice development.
7. Which of the following constituent is affected by cold hardening?
a) Carbohydrate
b) Protein
c) Lipid
d) Vitamins
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Explanation: Cold hardening is the process where it alters the behavior of the stomata. There is an increase in the root permeability. Cold hardening affects the lipid content of cell membranes. It lowers the optimum temperature for photosynthesis and respiration process.
8. Which of the following is not the chilling injury symptom?
a) Skin pitting
b) Water-soaking
c) De-greening
d) Cuts
View Answer
Explanation: Skin pitting is a common chilling injury symptom. This is due to collapse of cells beneath the surface. The pits are often discolored due to high water loss. Browning flesh tissues is another common feature of chilling injury. It results from the action of the polyphenol oxidase enzyme on phenolic compounds released during chilling. Water soaking is seen in leafy vegetables and some fruits.
9. What is the safe storage temperature for cucumber?
a) 7 °C
b) 10 °C
c) 12 °C
d) 5 °C
View Answer
Explanation: The safe storage temperature for cucumber is 7 °C. The safe storage temperature for avocado is 5-12 °C. The safe storage temperature for mango is 12-13 °C. The safe storage temperature for lemon is 10 °C.
10. Which of the following statements about chilly injury are correct?
Statement 1: Activities of membrane bound enzymes are disrupted.
Statement 2: Accumulation of toxic compounds.
a) True, False
b) True, True
c) False, True
d) False, False
View Answer
Explanation: The change in lipids membrane modifies the properties. The ion and metabolites moves across affected membranes and the activities of membrane bound enzymes are disrupted. There will be a breakdown of sub cellular compartments. There will be accumulation of toxic compounds like acetaldehyde.
11. Which of the following vegetable is least susceptible to chilling injury?
a) Cabbage
b) Tomato
c) Cauliflower
d) Broccoli
View Answer
Explanation: Cabbage is least susceptible to chilling injury. Whereas Cauliflower and broccoli are moderate susceptible to chilling injury. Tomato is highly susceptible to chilling injury. It depends on the structure of the product, composition of the product.
12. At what temperature does chilling injury occurs in celery?
a) 7 °C
b) 0 °C
c) 2 °C
d) -0.5 °C
View Answer
Explanation: Freezing injury will be commenced at -0.5°C. The symptoms of freezing injury include a water soaked appearance on thawing. The leaves wilt. Mild freezing can cause pitting in the petiole that leads to brown discoloration.
Sanfoundry Global Education & Learning Series – Fruits Processing.
To practice all areas of Fruits Processing, here is complete set of 1000+ Multiple Choice Questions and Answers.