Phytosanitary irradiation and fresh fruit quality: cultivar and maturity effects

Abstract

Purpose of review: The pre-export application of agreed phytosanitary measures for economically important species of fruit flies (eg, Bactrocera tryoni – Queensland fruit fly) and other high risk pests are a critical aspect of New Zealand's biosecurity requirements. There are a number of successfully implemented treatments allowing for the commercial trade of fresh produce from Australia to New Zealand. The “tool box” of agreed measures include the application of post-harvest treatments such as heat treatments, cold disinfestation, chemical dips/sprays and methyl bromide fumigation. Other non-treatment options include sourcing products from recognised pest free areas (PFAs), the use of systems approaches and recognised non-host status. Over recent years, there has been a need to revise the commercial application for several of the historically recognised treatment options. In particular, the effective banning of dimethoate as an accepted post-harvest treatment option for several products required the development and implementation of new alternatives to facilitate the long-standing market access for important commodities such as mangoes, tomatoes and capsicums. The application of irradiation technology in this instance has successfully fulfilled an important technological and trade need. Furthermore, irradiation has also facilitated the market access for new commodities, such as lychees, and paved the way for the implementation of long-term and sustainable export-import programmes.Findings: A significant volume of irradiated mangoes, lychees, tomatoes and capsicums are now purchased by consumers in New Zealand. It is very clear that not only does irradiation fulfil a technological need but it also fulfils a consumer need by making quality produce available at competitive prices. Consequently, a significant proportion of the New Zealand public will consistently buy irradiated fresh produce when it is available to them.Directions for future research: The recent approval by FSANZ for the irradiation of a range of new commodities will open up further opportunities for both new market access (eg, for cherries and other stone fruit) and also provide a commercially viable treatment alternative for products with existing market access to New Zealand (eg, grapes). Since the commercial application of irradiation treatments has now been in place for more than a decade, trust and confidence in the technical effectiveness of the treatment has improved as well as consumer acceptance. Significant investments in associated infra-structure requirements directly relevant to the fresh produce supplychain (eg, maintaining the cold-chain before, during and after treatment) has also sent positive signals that irradiation is a sustainable and long-term option amongst the current toolbox of treatment options. Governments and regulators must now build on the existing science-based approvals and take a more pragmatic stand to ensure that the regulatory frameworks and approval processes are less obstructive and time consuming so that consumers can exercise their free choice of buying or not buying a wider range of irradiated produce.