Supply Chain Quality Improvement - Technologies and Practices to Reduce Bruising

Flesh bruising is a major postharvest quality concern for the Australian avocado industry. It is responsible for around half of all internal defects detected at retail level. Preceding Hort Innovation projects ‘AV10019’ and ‘AV12009’ established clearly that flesh bruising is caused, and primarily expresses, in the supply chain post-ripener; i.e., in fruit that have commenced the softening process. Opportunity exists to improve fruit quality at retail by identifying and adopting measures that lessen or, ideally, eliminate flesh bruising. Doing so will ultimately lead to improved consumer satisfaction and bolster demand in the face of a domestically, and seemingly internationally, looming market over-supply. The current project sought to clarify the relative contributions of inherent fruit characteristics and external environmental conditions and management practices to bruise susceptibility. This was realised by thoroughly reviewing the current literature and in undertaking a directed series of experiments to investigate final fruit quality in response to prescribed simulated (i.e., lab-based) and actual (i.e., real world) supply chain conditions. Additionally, the project reviewed and tested technologies that could potentially be used by shoppers and retail staff to determine fruit firmness (viz., ripeness) stage without the undesirable consequence of physically damaging handling (i.e., squeezing). The tests included a prototype Avocado Decision Aid Tool recently dubbed the ‘Readycado’. This prototype had been devised and developed in the course of preceding project ‘AV12009’. In-store consumer testing suggested that this device could be well-received by shoppers. Knowledge generated by the project was shared with other R, D & E workers (e.g., projects ‘AV15010’ and ‘AV15011’) via Hort Innovation co-ordinated ‘Avocado Supply Chain Quality Improvement Program – Project Reference Group Meetings’ and with industry stakeholders, including growers, packers, ripeners, retailers, consumers and AAL

Reducing flesh bruising and skin spotting in Hass avocado

Flesh bruising is a major postharvest concern of the avocado industry. As much as ~ 80% of fruit on retail display can have some degree of internal quality issues, mainly flesh bruising. HIA Limited Project AV10019 was commissioned with the objective of identifying critical points in the supply chain where events that lead to flesh bruising happen. Also, the incidence of skin spotting at different stages of the supply chain was evaluated with a view to scope the need for future research on this defect. The target audience of this project is commercial producers, traders and research organisations

Adoption of Digital Technologies and Decision Support Systems in Horticulture Supply Chains

This paper presents key factors affecting the adoption of digital technologies and decision support technologies in horticulture supply chains. Using the case study method, in-depth interviews were conducted with decision-makers of three distinctive horticulture supply chains, complemented by site observations. The Technology Acceptance Model (TAM) is the theoretical foundation guiding this qualitative study. The findings indicate the constructs perceived ease of use, usefulness, attitudes, behavioural intentions, trust, social influence, and costs affecting adoption. The study contributes to the literature by presenting an integrated TAM model that can be used to understand adoption in horticulture supply chains. It strengthens TAM by providing evidence of its applicability to real-life industry settings and further creates a link to the unique adoption problems in industry. The practical contribution to ICT developers, industry peak bodies, and governments is that the inter-firms’ interactions need to be considered when designing decision support technologies and implementing improvement programs

Effect of preharvest bagging and of embryo abortion on calcium levels in 'Kensington pride' mango fruit

Bagging mango fruit during their development on the tree can reduce insect and disease damage. However, it is also possible that bagging can interfere with transpiration and associated calcium accumulation. Low calcium concentrations have been correlated with poor mango fruit quality. This study was conducted to evaluate the influence of bagging at various stages of fruit development on calcium concentration and postharvest quality of 'Kensington Pride' mangoes. Fruits were bagged at 41, 25 or 9 days before harvest. No statistically significant differences in either skin or flesh calcium concentration were found between the bagged (plastic or paper) and unbagged fruits. Postharvest weight loss was enhanced and shelf life reduced in the 'plastic bagged' fruits. In an ancillary study, calcium concentrations in 'Kensington Pride' nubbins (seedless fruit) were compared with those in seeded fruit, since it has been shown with apple fruit that greater seededness is positively correlated with increased flesh calcium concentrations. Conversely, however, calcium concentrations in the flesh of mango nubbins were found to be significantly higher (0.80 mg/g dry weight) than those in seeded fruit (0.58 mg/g dry weight) of similar size

Reducing skin damage and improving postharvest efficiency of Calypso mango

‘B74’ mango (marketed as CalypsoTM) was bred at Childers in subtropical Queensland specifically to overcome the inconsistent production of the cultivar ‘Kensington Pride’. Ongoing research is maximising its genetic potential in the main production regions. ‘B74’ mango fruit develops an attractive blush during growth and a full yellow skin colour when ripe, but small spots from damaged lenticels often appear on the skin. This affects the visual appeal but does not affect the flesh; nevertheless the value of the fruit is reduced. The project confirmed that fruit can have less LD if they are grown in hotter production, are smaller and more mature, have more blush, and are from trees that had more uniform flowering or smaller canopy area. However, these parameters accounted for only 32-35% of the variation in LD. Not irrigating the trees for 3-8 weeks before harvest may “dry” the fruit out and make them more resistant to LD but this was not observed. ‘B74’ is more prone to this lenticel discolouration (LD) than most other Australian mango cultivars, most likely because it has 3-4 times higher lenticel density on the fruit surface at harvest. LD is worse when the fruit are exposed to water either from rain or during harvesting. In order to reduce contact with water, the fruit were paper bagged (done commercially in apple and other fruit in Japan), or sprayed with a carnauba-based wax, two months or several days before harvest, respectively. Both treatments reduced LD in the ripe fruit. Bagging is labourintensive but may be profitable for high value markets, and wax sprays need commercial testing with whole tree spraying. LD is likely due to an oxidation reaction, similar to when cut apple turns brown. Reducing oxygen around or in the fruit, or using anti-oxidants may reduce the browning reaction. However, holding the fruit in plastic bags, fruit coatings and antioxidant dips before ripening had either no effect. The most promising approaches were eliminating water from the harvesting and packing procedures, and irradiating fruit for export when they were about three days from ripe. Both approaches add extra challenges to the harvest-to-consumer chain, but they may have application is certain circumstances. Mango fruit need to be harvested within 2-4 weeks of reaching minimum maturity to prevent fruit from falling from the tree. This short harvest window results in challenges with picking teams and equipment. Trials attempted to induce earlier or later flowering the spread the harvest window in the hotter production areas. Trials with Ethephon® sprays indicated its potential to stimulate earlier flowering. Removing flowers in the Katherine environment to encourage the trees to re-flower was unsuccessful. The ability to ripen fruit in transit from farm to market will reduce energy costs and infrastructure requirements in market. Commercial tests indicated that the newer 12 m rail containers can retain ‘B74’ fruit temperatures at about 18ºC, and several systems to manage carbon dioxide and ethylene concentrations (both important in fruit ripening) can be controlled

Effects of phosphonate and salicylic acid treatments on anthracnose disease development and ripening of 'Kensington Pride' mango fruit

This study investigated treatment of mango (Mangifera indica L.) fruit with 2 host defence-promoting compounds for suppression of anthracnose disease (Colletotrichum gloeosporioides). Cultivar ‘Kensington Pride’ fruit were treated at concentrations of up to 1000 mg/L with either potassium phosphonate or salicylic acid. Applications were by various combinations of pre- and postharvest dips and vacuum infiltration. Postharvest treatments at up to 2000 mg/L salicylic acid were evaluated in a second fruiting season. Fruit were either uninoculated or inoculated with the fungal pathogen. Colour, firmness and disease-severity were assessed during shelf life at 23°C. There were no significant (P>0.05) effects of potassium phosphonate or salicylic acid on anthracnose disease severity in the first season. Moreover, phosphonate or salicylic acid treatment did not significantly affect fruit colour or firmness changes. There were significant (P<0.05) reductions in anthracnose severity in the second season, especially at the highest concentration of 2000 mg/L salicylic acid. Mango fruit skin colour and firmness changes were also slowed down significantly (P<0.05). These effects of salicylic acid were attributed to inhibition of mango fruit skin ripening (senescence)

1-Methylcyclopropene treatment efficacy in preventing ethylene perception in banana fruit and grevillea and waxflower flowers

Premature ripening and/or senescence and abscission induced by exposure to ethylene are significant postharvest problems. Banana fruit and grevillea and Geraldton waxflower flowers are among affected commodities. Treatment with 1-methylcyclopropene gas or silver thiosulfate liquid can be used to prevent ethylene perception and response. Treatment of banana fruit with 10 nL 1-methylcyclopropene/L for 12 h at 20˚C afforded protection against subsequent serial treatments over 13 days of subsets with 100 L ethylene/L for 24 h at 20˚C. Protection of Grevillea ‘Sylvia’ inflorescences was effective only for 2 days. Thereafter, fruit and inflorescences regained sensitivity to ethylene. In contrast, neither banana fruit nor grevillea inflorescences treated with 10 nL 1-methylcyclopropene/L for 12 h at 2˚C were protected against ethylene. 1-Methylcyclopropene binding to ethylene receptors was apparently not achieved at the lower temperature. Increasing the 1-methylcyclopropene concentration to 100 nL/L, applied at 2.5˚C to banana fruit, achieved protection against ethylene. Waxflower sprigs treated with 10 nL 1-methylcyclopropene/L for 12 h at 2 or 20˚C regained full sensitivity to ethylene after about 2 and 4 days, respectively. In contrast, pulsing waxflower with 0.5 mmol Ag+/L as silver thiosulfate for 12 h at 2 or 20˚C afforded protection against ethylene for the 10 days duration of the experiment