Effect of O2 and CO2 partial pressure on selected phenomena affecting fruit and vegetable quality

It is likely that from the time of the Roman Empire and perhaps before, people involved in the storage of plant material as food recognized that atmospheric modification can provide some benefit in improving storability. However, active, commercial modification of the atmosphere for the preservation of fresh fruit and vegetables dates to the early part of this century. Early successes with apple fruit has lead to the attempt to apply modified atmospheres to a wide range of commodities. Responses to atmospheric modification are found to vary dramatically among plant species, organ type and developmental stage and include both unwanted and beneficial physiological responses, Desirable responses include a reduction in respiration, a reduction in oxidative tissue damage or discoloration, a reduction in the rate of chlorophyll degradation and a reduction in ethylene sensitivity with the concomitant reduction in the rate of ripening and other ethylene-mediated phenomena. Undesirable responses have included the induction of fermentation, the development of disagreeable flavors? a reduction in aroma biosynthesis, the induction of tissue injury and an alteration in the makeup of microbial fauna. The physiological bases for some of these responses to elevated CO2 and reduced O-2 are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.