Once the crop has been harvested the story does not end. Damaged or infected potatoes going into store will produce significant losses during storage.
The appropriate storage temperature depends on the potato market
- Seed potatoes are stored at low temperatures, around 35-39˚F, to minimize decay and to control the physiological age of the tubers.
- Fresh market potatoes are kept at around 37-41˚F to minimize weight loss and maintain a fresh, good-looking tuber.
- French fry and crisping potatoes need to be stored at higher temperatures; 44-48˚F, to minimize the level of reducing sugars. Reducing sugars accumulate below and above 48˚F, and the changes induced by higher temperatures are irreversible.
Crop nutrition is essential
The nutrients below have important effects on potato storage and cooking quality:
- Potassium - Potash affects bruising, enzymatic blackening and after-cooking blackening
- Calcium - Calcium helps prevent storage rots caused by Erwinia spp and also skin diseases
- Boron - Boron may reduce enzymatic blackening
- Magnesium - Magnesium may reduce enzymatic blackening
Growers can also influence potato storage and cooking quality by
- Selecting the right variety with the right cooking quality for the market.
- Irrigation scheduling to maximize quality characteristics.
- Minimizing damage during harvesting.
- Using in-store treatments (e.g. fungicides) to reduce tuber disease build-up.
- Controlling temperatures in storage.