Innovation in controlled atmosphere technology

Abstract

Purpose of review: C ontrolled atmosphere (CA) technology has been adopted worldwide as a sustainable postharv est technology which is not damaging to the environment and presents no risk to humans. This review offers guida nce on the latest developments in CA technology which have been adopted or are likely to influence the future use o f CA technology. Fin dings: The goal of having a dynamic CA environment which is controlled by the stored product has been ach ieved with the discovery and development of a chlorophyll fluorescence-based technology. The rapid adoption of 1- methylcyclopropene (1-MCP) as a postharvest chemical is likely to change the role of CA. CA will remain the pr e-eminent choice for storage of ‘organic’ fruits and vegetables but for ‘non-organic’ products, a combination of 1 -MCP and CA is more likely. There are interesting results from CA research on humidity, decay control with org anic volatiles, hyperbaric storage and ‘novel’ gases such as nitric and nitrous oxide. The combination of CA with on e or more complimentary techniques, although challenging, has b een attempted with some promising results. Limi tations/implications: Adop tion of chlorophyll fluorescence is limited to plant organs that contain chlorophyll. 1-MC P can have no effect or a negative influence on som e commodities. There may be b enefits demon strated with hu midity control, use of organic volatiles, hyperbaric storag e and ‘novel’ gases, but adoption may not occur due to lim ited benefit and unacceptable risks or costs. D irections for future research: I n the developed world, the increased consumption of ‘organic’ foods provides an in centive for future research and development of CA. Dynamic CA, either with chlorophyll fluorescence or with ano ther approach, will attract research. Combin ing CA with co mplementary strategies, e.g. decay or humidity contro l, delayed CA, high temperature CA, 1-MCP and other 1-cycl opropenes, is another promising research direction. Rese arch on the role of cytoplasmic acidosis in senescence and how it is affected by CA will yield useful wider anging information. Ke ywords: oxyg en; carbon dioxide; humidity; nitric oxide; nitrous oxide; chlorophyll fluorescence; dynamic contro lled atmosphere; 1-methylcyclopropene; Muscodo r albus; decay