Modified atmosphere packaging alleviates chilling injury in cucumbers

Abstract Cucumbers (Cucumis satious L.) packaged in perforated or sealed 31.75 pm (1.25 mil) low density polyethylene (LDPE) bags were found to have less severe chilling injury than nonwrapped fruit in storage at 5°C and 90-95X1 relative humidity. The onset of chilling injury was also delayed by the LDPE packaging compared to the nonpackaged control. The concentrations of CO, increased to 3% while 0, levels decreased to 16% in the sealed bags. Fruit in the sealed bags had the least decay. The 0, and COz concentrations inside the perforated bags changed very little from the ambient atmosphere. However, there was a marked difference in the weight loss between nonwrapped cucumbers and fruit from perforated or sealed bags. The weight loss of nonwrapped fruit reached 9% in 18 days while perforated and sealed samples lost less than 1% during the same period. Chilling stress induced increases in putrescine levels in all treatments but the sealed fruit had the highest levels of putrescine. Sealed fruit and perforated fruit also had higher content of spermidine than non-wrapped fruit. These high levels of polyamines may have contributed to the increase of chilling tolerance in fruit from perforated and sealed packages. 0 1997 Elsevier Science B.V