Subtopic: Controlled and modified atmosphere storage
Question Statement:
Which of the following gas composition modifications are characteristic of Controlled Atmosphere (CA) storage for fresh apples?
Options:
(A) Reduction of oxygen concentration ($O_2$) from $21\%$ down to $1 - 3\%$
(B) Elevation of carbon dioxide concentration ($CO_2$) up to $1 - 5\%$
(C) Scrubbing/removal of trace ethylene gas ($C_2 H_4$)
(D) Elevation of oxygen concentration up to $50\%$ to prevent anaerobic respiration
Answer Key:
A, B, C
Step-by-Step Solution & Explanation
Controlled Atmosphere (CA) storage extends storage life by slowing down respiration and senescence:
• $O_2$ is reduced to $1 - 3\%$ to suppress respiration without inducing anaerobic fermentation (A).
• $CO_2$ is increased to $1 - 5\%$ as a respiratory inhibitor (B).
• Ethylene ($C_2H_4$), the ripening hormone, is scrubbed using potassium permanganate ($KMnO_4$) (C).
High $O_2$ accelerates senescence (making D FALSE).