Reflections from the EAPR Post-Harvest Sector Meeting

Over 90 scientists, advisers and representatives from the global potato industry gathered for the European Association of Potato Research (EAPR) Post-Harvest Section Meeting in Norwich on the 12-14 March to discuss the latest progress in post-harvest research. The meeting provided a timely opportunity to address the complex challenges the potato storage sector is currently facing.

Storing in a post-CIPC world

Two sessions were dedicated to sprout control post-CIPC, reflecting the crucial challenges it poses to the industry. It’s now widely accepted that it is no longer a question of ‘if’ but rather a question of ‘when’ CIPC will go. Throughout Europe, this is likely to have slightly different consequences, as some EU member states currently have access to alternative sprout suppressants that others don’t. DMN for example, which has emerged as a promising alternative to CIPC, is yet to be approved in the UK but is already registered in a number of other countries in the EU. Results from trials across Europe and the USA have demonstrated that there are commercially viable options available for both the fresh and the processing sector. Further trials are needed to optimise the use of the different compounds and to investigate their use in combination as synergistic effects have been suggested by some research conducted to date.

What all EU countries will undoubtedly have to tackle is the issue of CIPC residue contamination in stores and the consequences that this could have on the potato trade in a non-renewal scenario. In such a case, the Maximum Residue Level (MRL) concentration would normally drop to the limit of quantification (LOQ) (0.01 ppm), putting stores at a risk of exceedance. Discussions are already being held with the authorities and data from store surveys is being provided by AHDB and researchers from other countries to try to get regulators to set a realistic temporary MRL for CIPC, which will accommodate some release of CIPC within previously-treated buildings and boxes.

Crucially, it’s time for potato storage to be approached with a different mind-set. Certain aspects of store management have previously been understated, like airflow or keeping stores sealed. However, without the ‘safety net’ provided by CIPC, these will now have a much bigger impact on storage efficiency. The ag-chem regulatory landscape is changing across Europe and transforming the status quo, spurring the industry to move towards a fully integrated approach to potato storage. Dormancy characteristics, cold temperature tolerance and ethylene sensitivity are all examples of variety attributes we will need to pay much more attention to in the coming years.

Quality indicators: it’s easier said than done

Another interesting session covered the use of biochemical indicators for quality aspects such as acrylamide levels and senescent sweetening. Starch re-synthesis was one of the traits identified as a potential marker for the irreversible build-up of sugars. Two studies highlighted the complexity of tuber physiology with respect to senescent sweetening.

This complexity was also reflected when volatiles were investigated as a potential indicator of blackheart (BH). This study was set up following the observation that fruit flies were attracted to BH lesions. Over 90 different volatile compounds were detected in affected potatoes and questions remain about their actual role in BH formation. More work is needed to turn some of these leads into practical solutions.

Engaging on all levels

Several speakers touched on the impact of crop morphology and physiology when loading, on disease development in store (wounding, temperature), or how storage conditions can have an impact on fry colour and acrylamide levels at the processing stage. This goes to show that storage cannot be thought of in isolation but should instead be viewed as an integral part of the supply chain, from farm to fork. Actively engaging with customers and suppliers upstream and downstream of the supply chain is therefore an important part of getting storage right.

On another level, engaging with technology innovators is one way in which storage can be improved and optimised for the future. The Innovation Session, hosted in partnership with Agri-Tech East, was an opportunity to raise awareness of smart sensing technologies and data management platforms and demonstrate how these can provide solutions to the challenges faced in store management.

The presentations at the EAPR Post-Harvest Section Meeting, prompted many discussions. Let’s harness the generated know-how and collaborative spirit of this conference and ensure it is put into practice in UK stores. Whether you are a grower, storage manager, advisor, scientist or policy maker, we all have a role to play in what are unprecedented times of change for our industry.

If you have such a store and are interested in participating, please get in touch with Adrian Briddon at SBCSR on 01406 359412 or via email at adrian.briddon@ahdb.org.uk.