Maintaining quality and presentation, or what is the proper technology for storing potatoes

Organizing the potato storage process is a rather labor-intensive, multi-stage process, the goal of which is to preserve the maximum volume of the crop until the new season.

Since complex physiological and biochemical processes continue in potatoes even after harvesting, it is very important to create and maintain ideal conditions (air temperature, humidity, ventilation) in the vegetable storage.

We will talk about the technology and storage mode of potatoes below.

Features for the household

Special organization of potato storage on the farm helps to avoid freezing of vegetables and minimizes damage to tubers by rot and disease.

For storing potatoes on the farm use special storage facilities with well-thought-out ventilation required for the volume of the room. As a rule, two methods are used for storing vegetables: in bulk and in containers (boxes, pallets).

Bulk storage involves pouring potatoes around the perimeter of the storage in one continuous layer. Separate space is left for the passage of vehicles unloading and loading vegetables. The bulk method is most often used for potatoes of one variety.

Container storage is the most suitable method for large farmsengaged in both growing and selling potatoes. The harvest is loaded into containers of different capacities, which, if necessary, can be easily moved to any storage location.

Mode

In order to ensure high-quality storage of potatoes, optimal air temperature and humidity parameters must be maintained in vegetable storage facilities.

During the main period the air temperature in the room should not exceed 2-3°C (otherwise there are high risks of tuber germination, activation of the rotting process and damage to the entire crop).

Optimal humidity parameters are 85-95%. When the humidity is below 75%, the tubers very quickly lose moisture and become lethargic and wrinkled.

Separately, they note such an important point in storing potatoes as ventilation. Lack of oxygen causes the tuber flesh to turn black, loses its taste and beneficial properties.

High-quality ventilation allows you to regulate temperature changes, air humidity, and stops the development of mold and mildew.

Technological periods

Conventionally, the entire storage time of potatoes is divided into four periods: curative, cooling, main, heating and spring, differing in duration and regime.

Medicinal

Immediately after harvesting the tubers from the field, the curative storage period begins. It lasts at least fifteen days (maximum period eighteen days).

Potato cells, saturated with suberin, are transformed into a wound periderm, which protects the tuber from excessive loss of moisture, as well as the penetration of pathogenic microorganisms.

At the same time, sugars are converted into starch, the process of transition to a state of deep dormancy is completed at the growth points, and the peel thickens.

During the entire treatment period, some diseases appear potatoes, which makes it possible to immediately reject unsuitable tubers, thereby saving the entire crop from damage.

To achieve maximum effect, the treatment period of storage must take place under certain conditions: air temperature from +18°C to +20°C, humidity 90-95%.

The lower the air temperature during the treatment period, the slower the healing process of damage to potato tubers. It is also unacceptable to reduce air humidity to 80% (otherwise excessive evaporation of moisture will slow down the healing process).

Important point: storing potatoes during the healing period should only take place in a room with good ventilation. For example: under a canopy, in temporary piles or in special storage facilities equipped with forced ventilation units.

Potatoes are blown with warm air at least six times a day for half an hour at intervals of three to four hours. Active ventilation promotes rapid drying of tubers and accelerates the healing process.

Cooling

An intermediate period that allows you to prepare potatoes for long-term storage at low temperatures is cooling.

At this stage, there is a gradual decrease in temperature (by 0.5°C per day). To do this, the room in which the crop is stored is ventilated with air whose temperature is 3°C lower than the temperature in the embankment.

Ventilation is carried out for six to eight hours a day. The air humidity in the room should be at least 95%.If the storage facility is not equipped with forced ventilation units, the potatoes are cooled at night with outside air.

Under natural ventilation conditions, cooling takes an average of forty days, in storage facilities with active ventilation installations - up to twenty days.

Main time

The period of time from cooling until the potato harvest is sold (or seeds are prepared for planting) is the main storage.

An important point: in order for the potatoes to retain their appearance and useful properties until the moment of sale, during the main storage in the warehouse it is necessary to maintain a constant level of humidity and air temperature.

Depending on the intended purpose of the batch of potatoes, The temperature regime is maintained at the level:

• seed material +2-4C°;
• table potatoes +4-6C°;
• vegetables for processing (for example, French fries) +6-8°C;
• potatoes for making snacks (chips, dry mashed potatoes) +8-12°C.

The difference in temperature conditions is explained by the following: the lower the storage temperature, the more sugars accumulate in the potatoes, causing the product to darken during processing (for chips and mashed potatoes this is an extremely undesirable moment).

During primary storage, the temperature in the bulk must be constantly monitored. The indicator should not fall below +1°C (a sharp decrease is fraught with freezing and destruction of the entire crop).

In order to maintain the presentation of potatoes during the main storage period the storage room maintains 80-85% air humidity and provides forced ventilation at least two to three times a week for thirty minutes.

In winter, the potato embankment is ventilated using special installations, and with an increase in temperature in the embankment - with outside air. In the case when fogging occurs in the upper layer of the potato embankment, the air temperature in the storage and embankment is equalized by heating the upper layer using special heaters.

Spring

The end of February and the beginning of March is the spring storage period for potatoes. It is at this moment that it is very important not to miss the beginning of bud germination on the tuber. For this purpose, the air in the storage facility is cooled to 1°C (natural ventilation is used at night and in the morning).

Heating

The final storage period is heating. In order to preserve the presentation of previously cooled tubers, potatoes must be warmed up before transportation.

For this ventilation is stopped in the storage room, the air is heated to +10°C. For seed material, the air in the room is heated to 18°C ​​(a necessary indicator for activating potato growth processes).

Attention: in order to avoid sweating (and subsequent rotting) of the tubers, the temperature in the mound must be raised gradually. Temperatures are monitored every day. To do this, a thermometer is placed on every 50 tons of potatoes, at a distance of 30-50 cm from the top layer.

Sorting potatoes at the heating stage is ineffective, since damaged tubers can only be selected in the top layer, and more thorough sorting injures cooled potatoes, which only increases the percentage of crop loss.

Preparation for implementation

The final stage of the technological process of storing potatoes is preparation for sale (commodity processing). First of all, potatoes are sorted by hand, rejecting rotten, defective tubers. During preparation (usually a process that takes at least four days), the potatoes are exposed to warm outside air.

This is necessary in order to reduce injury to tubers during the sorting process. Sorted vegetables are calibrated by size. The parameters are set by the market (minimum and maximum sizes are specified).

Conclusion

Compliance with potato storage technology allows you not only to preserve the appearance and beneficial properties of vegetables, but also to reduce losses to a minimum and preserve high-quality seed material to obtain a larger harvest in the new season.