Physiological and Microbiological Characteristics of Fresh-cut Cucumber Stored in CA/MAP in Relation to High CO2 Atmosphere

<jats:p>Fresh-cut cucumber slices were stored at 10 and 20 °C in high CO<jats:sub>2</jats:sub> controlled atmospheres (5%, 10%, and 20%) or in MAP of OPP non-perforated and perforated with 50 micro m pores (P-plus) films. In CA storage, respiration rates and surface yellowing of slices were reduced by high CO<jats:sub>2</jats:sub> atmospheres at 10°C, but increased with increasing CO<jats:sub>2</jats:sub> levels at 20 °C. Counts of mesophiles, psychrotrophs and coliform group on slices stored at 10 °C were not affected by high CO<jats:sub>2</jats:sub>, except lactic acid bacteria, which the counts increased when stored in 20% CO<jats:sub>2</jats:sub>. At 20°C, all bacterial counts were higher with slices in 10% or 20% CO<jats:sub>2</jats:sub> than those in air or 5% CO<jats:sub>2</jats:sub>. For MAP study, the used films were non-perforated OPP films (1170 mL/m<jats:sup>2</jats:sup>/day/atm, O<jats:sub>2</jats:sub> permeability) and P-plus films having high (51000 and 74000 mL/m<jats:sup>2</jats:sup>/day/atm for storage at 10 and 20 °C, respectively) and low (17000 and 51000 mL/m<jats:sup>2</jats:sup>/day/atm for storage at 10 and 20 °C, respectively) O<jats:sub>2</jats:sub> permeability. Cucumber slices were stored in MAP for 7 days at 10 °C and 2 days at 20 °C. The CO<jats:sub>2</jats:sub> accumulated to 17.5% and 30% and O<jats:sub>2</jats:sub> depleted to 2.5 and 3% at 10 and 20°C, respectively, in the non-perforated OPP film packages. Ethylene accumulated only in non-perforated OPP films at both temperatures. Growth of coliform group at 20 °C and lactic acid bacteria at 10 and 20 °C was greater in slices packaged in non-perforated OPP films than in P-plus films, while growth of mesophiles and psychrotrophs was similar in any packaging films. At the end of storage period, the bacteria isolated frequently from cucumber slices were Enterobacteriaceae and plant pathogenic bacteria. Lactic acid bacteria such as <jats:italic>Leuconostoc citreum</jats:italic> were detected on slices in non-perforated OPP films.</jats:p>