SUPERATMOSPHERIC OXYGEN CONDITION COMBINED WITH CARBON DIOXIDE LEVELS AFFECT THE RESPIRATION RATE OF FRESH-CUT BUTTER LETTUCE

The effect of different O₂ levels from 0 to 100 kPa in combination with 0, 10 and 20 kPa CO₂ on the respiration metabolism of greenhouse grown fresh-cut butterhead lettuce (Lactuca sativa L. var. capitata L.) was studied.
Fresh-cut lettuce was stored during 3 – 4 days at 1, 5, and 9°C. Fresh-cut lettuce exposed to 20 to 100 kPa O₂ combined with 0, 10 and 20 kPa CO₂ showed a CO₂ production rate of 40 to 60 nmol kg^-1 s^-1 at 1°C. When lettuce was exposed to 2 to 5 kPa O₂ in combination with 10 to 20 kPa CO₂, it had significantly increased CO₂ production relative to 0 kPa CO₂. O₂ partial pressures between 5 and 100 kPa had only a small effect on the respiratory activity of fresh-cut lettuce.
Moderate CO₂ level (10 kPa) could reduce the oxygen consumption rate of fresh-cut lettuce.
This effect was more pronounced at higher temperatures.
High CO₂ levels (20 kPa) probably caused a metabolic disorder increasing the respiration rate of fresh-cut butter lettuce.
The respiratory quotient ranged between 0.7 and 1.0 at O₂ partial pressures from 20 to 100 kPa at all temperatures.

IX International Controlled Atmosphere Research Conference

V.H. Escalona, B.E. Verlinden, S. Geysen, B.M. Nicolaï

high O₂ level, CO₂ concentrations, respiratory activity, minimally processed, modified atmosphere packaging, respiratory quotient

https://doi.org/10.17660/ActaHortic.2010.857.12