Friday, 15 May 2020
The coronavirus outbreak has completely shifted market dynamics for potatoes and has brought about many storage-related questions as a result. Read our Storage FAQs for some answers.
1. My unloading date has been put back by my customer. What issues might I have to deal with?
First, if the store is just ambiently cooled and fairly well insulated, a store will normally be able to maintain temperatures below around 8 °C until mid-late May. After this time, refrigeration would normally be required to maintain cool store temperatures.
- For ambient only storage the priority is to move the stock ASAP while it still has some value.
- For refrigerated stores, review the likely customer/market requirements particularly for whether there will be demand to move the stock at a later date. Consider earlier movement where possible.
Sprouting and quality levels will be the main concerns. An additional dose of CIPC may be required to extend storage life, especially if temperature control is marginal.
Keep an eye out for any change in quality: longer term storage can lead to more softening of tubers and may also result in other problems, such as senescent (old age) sweetening or higher levels of disease.
If quality permits and refrigeration is available, consider reducing temperature for longer-term stored material.
Critically, maintain a dialogue with your customers about prioritising unloading of ambient stores as we move into early summer and particularly for varieties susceptible to senescent sweetening.
For stores previously treated with CIPC, longer storage duration will impact on the time available for cleaning and decontamination this summer. This will be a priority task, to ensure continued compliance with new residue legislation (a new, temporary MRL is expected shortly) following CIPC’s loss of approval.
2. I have had to change my marketing plans. Can I sell processing potatoes for fresh?
Yes you can, quality permitting. The Potato Industry CIPC Stewardship Group (PICSG) recently announced that Potatoes treated with CIPC at rates between 24 and 36 g/t may now be marketed using fresh supply chains, as long as crops are tested and comply with the Maximum Residue Levels (MRL).
3. My stores are nearly empty. What work can I be doing over the coming weeks to best prepare my stores for next season?
CIPC-treated stores must be cleaned to comply with the much-reduced MRLs expected next season. A thorough job must be done to remove all potential sources of CIPC contamination and we recommend you make a start as soon as possible.
Before store cleaning is started, you will need to carry out a risk assessment. Hazards you will likely come across include but are not limited to:
- Inhalation of dust
- Working at height
Follow HSE guidelines on how to carry out a risk assessment.
If your store has a history of CIPC application, follow the recently released EU-wide guidelines to remove as much of the chemical’s legacy from the store as possible.
If there is no history of CIPC application, then prepare stores as usual. More details on crop debris removal and disinfection can be found on our store cleaning page.
Basic post-storage checks include that equipment such as fans and fridges are functioning correctly.
If the system includes a fridge, check with your local service companies on their availability during the COVID-19 restrictions. If possible, book a service early to ensure your system is checked and fully up to speed in time for harvest. They need to ensure that the fridge gas level is correct, fridge coils are clean and that condensers are working properly and outlets are clear to allow heat to be removed to outside.
Check that air ducts are unobstructed and in good repair and that lateral shutters work smoothly. Inspect louvres closely for damage or misalignment that prevents them closing fully.
Verify that sensors are accurate by comparing against a good hand held thermometer, ideally in water (at a temperature in the range the store runs at) or, alternatively, melting ice (0 °C). Tidy up sensor leads, checking for damaged or stretched cables.
It is expensive to control the air within a store and a well-sealed store minimises the cost and improves control. Check store fabric integrity, ensuring that doors seal correctly and repairing gaps where possible.
Remove any outdated chemical signage.
For any questions on storage, call the storage advice line free of charge on 0800 02 82 111 or email firstname.lastname@example.org.