3. Results
3.1. Effect of 1-MCP on fruit quality
Fruit firmness generally exhibited a declining trend during
storage at ambient temperature, while 1-MCP treatment effectively
delayed the decline of firmness (Fig. 1A). SSC increased slowly
and thereafter declined in all treatments during storage. The
highest SSC values occurred at the 14th days in control fruit, and at
28th day in 1-MCP-treated fruit, respectively (Fig. 1B). This
indicates that 1-MCP effectively inhibits the decrease of SSC and
is beneficial for maintaining fruit postharvest quality.
3.2. Effect of 1-MCP on the content of organic acid and TA
As shown in Fig. 2, the changes in TA displayed an overall slowly
decreasing trend throughout the entire storage period, because
organic acids, as respiratory substrates, are usually degraded in the
TCA cycle. In apple fruit, malate was the main organic acid, citrate
and succinate were also detected at low levels. In parallel to
changes in TA, the three individual organic acids decreased during
fruit storage.1-MCP treatment effectively inhibited the decrease in
malate and citrate content, resulting in higher acidity in apple fruit
(Fig. 2A–C), demonstrating that 1-MCP was able to mediate organic
acid metabolism.
Fig. 1. Changes in firmness (A), soluble solids content (SSC) (B) of apple fruit during
s