1-Methylcyclopropene affects the shelf-life quality of controlled atmosphere stored ‘Cold Snap™’ pears

Abstract

1-Methylcyclopropene (1-MCP) and a controlled atmosphere (CA; elevated CO2 and low O2 partial pressures) preserve the overall quality of ‘Cold Snap™’ pears during low temperature storage, including minimizing physiological disorders. In two separate years, we determined the impact of 1-MCP (0 or 300 nL L−1), pre-storage conditioning (0, 3, or 7 d at 3 °C), and CA (18 or 2.5 kPa O2, and 2 kPa CO2) on the shelf-life quality of ‘Cold Snap™’ pears following their removal from storage at 0 °C. In both years, 1-MCP effectively reduced rates of ethylene production and limited peel yellowing and fruit softening following the transfer of stored ‘Cold Snap™’ pears to ambient conditions for up to 14 d, regardless of pre-storage conditioning and CA regimen. Moreover, 1-MCP-treated fruit stored under 2.5 kPa O2/2 kPa CO2 developed lower incidences of senescent scald, regardless of the pre-storage conditioning period. In year one, this treatment combination also limited internal breakdown and internal cavity development, whereas the incidence of internal cavities was highest in 1-MCP-treated fruit in year two, regardless of pre-storage conditioning period, O2 partial pressure in the storage atmosphere, and shelf-life duration. Principal component analysis revealed that the occurrence of senescent scald and internal breakdown in ‘Cold Snap™’ pears were associated with high rates of ethylene production, peel yellowing, and softening. Similarly, internal cavity development was correlated with most ripening attributes, although the link with fruit softening was inconsistent across both years of the study.