- Cultivar influences fruit quality after export
- Likelihood of flesh disorders in white nectarines and peaches increases with increasing sea freight duration
- Fruit maturity at harvest impacts on subsequent ripening and flesh disorders
- Changes in fruit firmness along the export chain can be predicted
- Preliminary cultivar recommendations for sea freight
Video: Introduction to Stonefruit Simulation Research
Research will be focusing on
- storage trails - simulating sea freight
- measuring cultivar performance with ripening, changes in flesh firmness, and physiological disorders
- export varieties of white & yellow fleshed peaches and nectarines, and plums
- what post-harvest treatments can be used to mange any disorders?
- what impact do dis-infestation have on fruit?
- modelling: predicting shelf-life during export based on temperature and duration
As part of this project and focused on stonefruit, what we're looking at is a few areas. One is taking some of these import and export cultivars and looking at the storage potential. So simply storing them or simulating sea freight and import and storage in the importing country using the same temperatures that they would use in during export and looking at their performance, at the cultivars performance in terms of ripening, changes in flesh firmness and any physiological disorders like flesh browning that may occur. And we're looking at mainly white fleshed peaches and nectarines, some yellow nectarines as well as some plums. And this will provide industry with, or will give them some idea of how long these cultivars can be stored for before we see some problems coming up. So we do understand that there are some issues with some of these cultivars, but we're just confirming them by doing these storage trials. There's two other areas where we're sort of specifically looking at. One is what kind of post-harvest treatments we can apply to these cultivars to potentially reduce the severity of the physiological disorders. And also looking at what effect the current post-harvest treatments such as dis-infestation has on subsequent quality in export markets, so a sort of two pronged attack. And the final area we're looking at is to actually try to predict remaining shelf-life during export based on temperatures occurring during the export chain, and the duration of the export chain. And so we're hoping to develop a model that is cultivar specific, that you can plug in your export temperatures, time it's taking to get to importing markets, time that fruit is stored in the importing country, and the model will be able to tell you what the remaining shelf life is of that fruit.
What we found is because these cultivars seemed to be quite susceptible to chilling injury and flesh browning, that impacts on the predictive ability of the model that we will develop. So, we've taken a step back now and really considering which cultivars can be exported by sea freight and, if potentially there's going to be some quality issues with chilling injury, for example, then do we strictly stick to airfreight, which is obviously a much shorter timeframe?
Presentation from Stonefruit Research Roadshow August 2019
- Predicting fruit quality and shelf life
- Simulated sea freight and quality prediction – Majestic Pearl
- Fruit quality issues – SSC and cool storage
- Air freight temperature vs flesh firmness (kgf)
- Stone fruit pre-conditioning – a solution?
- Preliminary cultivar recommendations – Extended storage
Video: observations from research on cultivars, flesh disorders, harvest maturity, and predicting fruit firmness.
- a number of cultivars have limited cool storage potential
- simulations indicate risk of chilling injuries for these cultivars
So far, it's two and a half years into the project, and I guess the key story that's come out of the work we've been doing is that many of the cultivars we are exporting into Asian markets, particularly the white fleshed peaches and nectarines, seem to be under-performing in the sense that their storage potential is limited in terms of storage duration at low temperature, which is what is required for sea freight export. And sea freight export usually takes three to four weeks once it leaves Australia and gets to Asian markets. For example, China. And during that time, we're simulating that sea freight export and we're finding at the end of the sea freight leg that we're observing some physiological disorders commonly known as chilling injury. And the main symptom is flesh browning and loss of texture, So the loss of eating quality. It's quite a concerning because these cultivars have been planted out in quite high numbers, high volumes, and they are import and export cultivars. So I guess what our aim now is to determine what are the factors influencing the severity of these disorders. And that's within sort of a research sphere, but then there's the logistics of how does the industry shorten the export duration from harvest right through to the importing country? Because at the moment it's it's probably five to seven days from harvest to the freight forwarder, and then we're looking at probably four weeks sea freight durations, so you're already at five weeks storage, low temperature storage, but five weeks storage duration before it even gets the importing countries.
The Serviced Supply Chains project is funded by the Hort Frontiers Asian markets Fund, part of the Hort Frontiers Asian strategic partnership initiative developed by Hort Innovation, with co-investment from Agriculture Victoria, the Department of Agriculture and Fisheries Queensland (DAFQ), Montague Fresh (summerfruit), Manbulloo (mangoes), Glen Grove (citrus), the Australian Government plus in-kind support from University of Queensland and the Chinese Academy of Sciences.