The processes of wound healing and drying is easier to control in a box-storage.
Attention to the weather during the storage period is an important part of good storage. It starts immediately after storage begins. Even after wound healing, it is essential not to cool down the product too quickly and to remain alert by checking for rot daily. By keeping an eye on the weather forecast, you can avoid missing out on the opportunity of ventilating with drying outside air during warm autumn days. If you miss these moments, ventilation is often not possible and rot can spread quickly.
An effective grower stores his product in an appropriate storage space
The answer to the question of how best to store potatoes is often directly related to the purpose of cultivation and sale. Until now, potatoes to be processed into crisps or French fries have generally been stored in bulk, although for the extra-long storage period of 5 months or longer, more and more potatoes of top quality are also stored in boxes. This is happening more and more often, especially with potatoes suitable for fresh French fries, while box storage of high-quality crisp potatoes is also becoming increasingly popular. However, most of the cultivated crisp and French fries potatoes are bulk lots, usually of the same variety, intended for processing into dried and/or frozen products. Harvesting mainly takes place later in the year. The working days are long because a lot of work has to be done due to the often limited number of harvestable days. In such circumstances, bulk storage is an advantage, because storage equipment such as hoppers, duo belts and store loaders can be used to store up to 100 tons of product per hour.
An effective grower allows for good wound healing
After storage, the wound healing and drying phases are often intermingled. They are definitely correlated. Depending on the purpose of the potatoes and the need for good skin quality, it can be very important to have an intense drying process at the start of storage as fungi will then not be able to flourish and affect the skin. The disadvantage is that, during drying, extra moisture evaporates from the tuber, resulting in weight loss and therefore fewer marketable kilos. For healthy and mature potatoes for processing, the drying period after initial storage is often shorter than that for table and seed potatoes, because they are often better hardened off. Therefore, more attention may initially be paid to wound healing. Wound healing after drying is very important. It is faster at higher than at lower temperatures. Depending on the tuber temperature and the presence or absence of rotten tubers and wet soil, the temperature of wound healing is between 13 and 18 degrees Celsius. The faster the wound healing can take place, the lower the storage losses.
An effective grower limits storage losses
After the period of wound healing, the evaporation of moisture and the cell respiration of the tubers during cooling are important causes of weight loss. A temperature reduction for cooling the tubers can be achieved with the help of two principles of physics. First of all by means of heat transport, transfer and discharge, thanks to the principle of forced convection, in which the air flows past the tubers. Secondly, by heat dissipation of evaporating moisture at the skin surface of the potato, which in turn is the result of a vapour pressure difference between the ventilation air and the moisture of the tuber.
Ventilation with air with a high relative humidity prevents evaporation from the tuber.
The latter is also the reason why wet potatoes sometimes cool down too quickly and therefore get even colder than the passing ventilation air. This latter mode of weight loss can be minimised as much as possible with good skin resistance, which inhibits evaporation from the tuber. Wound healing is therefore of great importance when it comes to reducing weight loss.
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