Why do fresh vegetables spoil quickly?

Fresh vegetables spoil quickly primarily because they remain living organisms after harvest, continuing to undergo physiological processes that lead to deterioration.12

Once harvested, vegetables are deprived of their natural nutrient supply, triggering a senescence process (aging). This leads to several key factors that accelerate spoilage:1

• Enzymatic Activity: Natural enzymes within the plant cells, such as cellulase and pectinase, begin to degrade cell walls, causing the vegetable to soften and lose its texture. Other enzymes, like polyphenoloxidase, can cause browning and off-flavors.13
• Respiration: Even after being picked, plant cells continue to respire, breaking down carbohydrates for energy. This process consumes the vegetable's internal resources, leading to a loss of quality and nutritional value.13
• Chemical Oxidation: As enzymes break down cellular structures, chemical oxidation occurs, further degrading flavor and nutrients.1
• Microbial Attack: The breakdown of cell walls and the release of internal nutrients make the vegetable highly susceptible to invasion by bacteria, yeasts, and molds, which rapidly cause decay.145

To mitigate these effects, vegetable processing techniques like refrigerated storage, blanching, and freezing are used to slow these life processes and deter microbial growth.62