How Should Potatoes Be Stored? A Full Analysis of Scientific Preservation Techniques

How to scientifically store fresh potatoes for seed, food and processing use is a key link in extending the potato industry chain. Through scientific storage, market supply and demand can be regulated and value can be increased by 20% to 30%. Through in-depth investigation and research and production practice, the author discusses the current potato storage situation in Weichang County, the existing problems and scientific storage methods.

1. Current potato storage situation in Weichang

Although farmers in Weichang have the habit of storing potatoes and have accumulated rich storage experience, many storage technology problems still exist. The whole county has more than 100,000 self-regulating temperature and humidity potato cellars, storing more than 200 million kg of fresh potatoes annually. Generally, in winter and spring the temperature inside the cellar is kept at 3 to 4°C and the humidity at 85% to 95%. The storage period runs from entering the cellar in September to leaving the cellar in April of the following year, lasting about 200 days. According to surveys, 60% of farmers store potatoes relatively well, with losses within 10%, and the best losses not exceeding 5%, which shows that the potato storage technology of Weichang County farmers has reached a certain level.

2. Problems in storage and analysis

Mixed storage without regard to use. Some farmers' homes have only one cellar, and food potatoes, seed potatoes, commercial potatoes and processing potatoes are mixed and stored in one cellar. This not only causes variety degeneration and the spread of pathogens affecting seed quality, but is also unfavorable for maintaining the commercial quality of commercial potatoes, the quality of food potatoes and the processing value of processing potatoes.

The quality of potatoes entering the cellar cannot be guaranteed. The quality of potatoes entering the cellar means that the potato tubers entering the cellar are required to be intact, with dry skin, no disease spots, no rot, no freezing injury, no wounds, no soil and no other impurities. When some farmers harvest and put potatoes into the cellar, they do not dry or select them, mix soil and tubers together, put diseased and damaged potatoes in together, or dump potatoes from the cellar mouth into the cellar, bruising the tubers and causing artificial damage to the tubers, and so on. This causes high humidity in the cellar and poor ventilation, satisfies the conditions for pathogen reproduction and infection, leads to cellar rot, increases losses, and also easily causes early sprouting of tubers.

Improper management during storage. Some farmers follow the bad habit of "natural management", sealing the cellar very tightly and not opening the cellar mouth again until spring when potatoes are taken out, with no inspection or ventilation in between. This leads to freezing of the cellar, cellar rot, heat injury, sprouting, black heart and other phenomena, causing major economic losses. Others fear freezing and focus on keeping warm, without ventilation during storage. The respiration of tubers produces a large amount of carbon dioxide. First, this obstructs normal respiration of the tubers, suffocates the sprouts and affects emergence. Second, people entering the cellar immediately may suffocate, causing personal accidents.

Potato cellar construction is unscientific. First, @#@185@#@ is improper. In some places the groundwater level is high, the humidity in the cellar is high, and water even appears. Some locations are shady and face the draft. Second, the soil covering the cellar top is thin and the cellar is shallow, causing freezing injury. Third, ventilation holes and ventilation channels are unreasonably arranged or not installed, blocking the exchange of temperature, humidity and gases in the cellar.

3. Suggestions for improving storage methods

Carefully handle tubers before they enter the cellar. Achieve "one dry and six without". That is, dry potato skin, no diseased tubers, no rotten potatoes, no wounds, no broken skin, no frozen tubers, and no soil or other impurities.

Ensure winter storage quality in the field. Disease spots and rotten potatoes are the greatest hidden danger for cellar rot after entering the cellar. Most diseased and rotten potatoes before entering the cellar come from late blight in the field. Therefore, timely prevention and control of late blight is the most effective technical measure to reduce diseased and rotten potatoes. In addition, increase the aging degree of potato skin and enhance its protective and injury-resistant ability. Agronomically, measures such as pressing vines before harvest, cutting vines, spraying non-selective herbicides and delaying harvest can all achieve the purpose of aging the potato skin.

Store in separate cellars. Store separately by variety, grade and use in single cellars (rooms). Generally, each household should build more than two storage cellars, or one cellar with multiple rooms, to ensure the seed quality and commercial quality of stored potatoes.

Strengthen management during storage and create the best storage environment and conditions. Suitable storage temperature and humidity: seed potatoes and food potatoes 3 to 4°C, processing potatoes 7 to 8°C, relative humidity about 90%, with a safe range of 80% to 90%. Change the past practice of no management all winter to regular inspection, and deal with problems promptly when found. The principle is "prevent both freezing and heat, prevent both moisture and dryness". According to the storage period, "prevent heat at both ends and prevent cold in the middle". The specific measure is to regulate temperature and humidity through ventilation and air release.

Improve the construction structure of storage cellars and increase regulation capacity. The main point is to add natural ventilation and air exchange facilities, and gradually use forced ventilation and air exchange equipment. According to economic strength, large and medium modern storage cellars with fans, main air channels and branch air channels, made of cement, brick and stone structures, can be built.