2.2. 1-MCP treatment, cold storage and sampling
Hardy kiwifruits were randomly divided into four lots (15 kg/a lot), and each lot was kept in a 50-l plastic container. Two lots were exposed to 20 μl/l 1-MCP for 16 h at 10 °C. 1-MCP was released by adding a buffer agent to calculated amounts of Smart Fresh powder (Agrofresh Rohm and Hass, Philadelphia, USA) according to the manufacturer’s instruction. The other two lots were kept under the same experimental conditions without 1-MCP. After treatments with or without 1-MCP, each lot was again subdivided into 15 groups (1 kg/group) and placed in a plastic tray (20 × 10 × 5 cm) without a cover. They were stored at 1 ± 0.5 °C in ambient air with a relative humidity of 75–80% to simulate commercial cold storage. As replicates for each treatment, three plastic trays were analyzed weekly for quality attributes during cold storage. For gene expression analysis, fruits were sampled at zero, three and 5 weeks. To test the anticancer properties of the fruit extracts, harvested fruits were immediately frozen at −80 °C, freeze-dried, and powdered.