Equilibrium modified atmosphere packaging or EMAP used primarily for fruit and vegetables; either the pack is flushed with required gas mix or the produce is sealed within the pack with no modification to the atmosphere.
Equilibrium modified atmosphere containing 2-5% oxygen and 3-8% carbon dioxide balance by N2, have been shown to delay maturation and softening of vegetables and reduce chlorophyll degradation, microbial spoilage and enzymatic browning.
It is also inhibiting undesirable pinking on prepared leafy green salad vegetables.
Equilibrium modified atmosphere attained are influence by produce respiration rate which itself is affected by temperature, produce type variety, size, maturity and severity of preparation; packaging film permeability; pack volume, surface area and fill weight and degree of illumination.
Inside the package, an equilibrium becomes established when the O2 transmission rate of the packaging film is matched by the O2 consumption of the packaged commodity.
The respiration of the living plant tissue results in the production of CO2 which diffuse through the packaging film, depending in the films CO2 transmission rate.
The type of packaging film selected is based on the film O2 and CO2 transmission rate which is required to obtain a desirable equilibrium modified atmosphere.
Equilibrium modified atmosphere packaging
