KR20090009010A - Method for storage of agricultural products using submerging and apparatus thereof - Google Patents

Abstract

A submersion storage method of agricultural products and a device are provided to preserve the quality characteristic of the fruits and vegetables produced according to season by storing them in cold water. A submersion storage device of agricultural products includes refrigerator(10), brine tank(12), exchanger(13) and submersion tank(11). The refrigerator cools the brine. The heat exchanger heat-exchanges cold water of the submersion tank and the cooled brine. The submersion tank cools the agricultural product with the heat-exchanged cold water.

Description

Method for Storage of Agricultural Products Using Submerging and Apparatus Thereof}

The present invention relates to a method and apparatus for storing agricultural products by immersion. More specifically, in the long-term storage of fruits or vegetables of agricultural products, install a storage tank in a certain underground space and fill the tank with vegetables or fruits to be stored inside to fill the water so that it can be sufficiently submerged. After filling, reduce the temperature of the submerged water to the lowest temperature suitable for the preservation of vegetables or fruits by using the pre-installed cooling device to suppress the respiratory, transpiration and lodging effects that are most important for long-term preservation. Long-term storage of vegetables and fruits.

 Most vegetables and fruits contain low amounts of carbohydrates, fats, and proteins, while they contain vitamins, minerals, and other bioactive substances. Most fruits and vegetables contain high moisture of about 90 ~ 95%, so it is easy to deteriorate and change. For long-term preservation, use methods such as refrigeration storage, freeze drying, pickling, gas storage, irradiation, and chemical use. However, there is a limit to maintaining the freshness for a period of time while maintaining the original ingredients.

In general, agricultural products swiunde cause spoilage by fungi and bacteria during storage Among apple or pear with blue mold disease (pen. Expansum), deep disease (fusarium sp . ), Gyunhaekbyeong (sclerotinina fructigena ), yunmun disease ( physalospora piricola ), gray mold ( botlytis) cinerea ), black fungal disease ( rhizopus nigricans ) and carrots, cabbages, and tomatoes are more often called alternaria radicina and bacillus carotovora .

The storage means of grains have been developed a lot and have been stored without packing, carbon dioxide storage, irradiation, chemical storage, sealed underwater storage, and fruits are stored at low temperature, ice film storage, freezing storage, gas storage. Etc. In particular, potatoes, sweet potatoes, radishes, cabbages, carrots, pears, apples, oranges, etc. are dug deep into the ground and stored.

Vegetables are produced not only in terms of quality but also in terms of production cost, which is advantageous in terms of production cost, which helps farmers' income. However, since they are shipped in a short period of time, the price of production farmers decreases due to supply and demand imbalance. The damage is great. In addition, consumers are inevitably repeating the purchase of high-priced vegetables after a short shipment. In order to improve this, conventional methods of storing vegetables are to dig a field in the production site, cover it with soil, and store it in a crypt. The natural temperature (usually 15 ℃) management method is a natural environment that suppresses general bacterial growth. Although it is the best method used, it is difficult to apply in real life because of the limitation of storage. Recently, the storage method using the cold store is the most common, but the continuous growth, breathing, transpiration, and lodging, depending on the characteristics of the production of agricultural products that continue after harvesting. ), The consumption of self nutrients and the loss of freshness and flavor due to the continuous evaporation of water. As a result, there is a limit to the effective control of the growth of decaying microorganisms, so vegetables typically set 30 to 50 days as the storage limit, and after 50 days, the loss rate increases rapidly as the storage period is extended, so the effective storage period for refrigerated warehouses is increased. Is managed for no more than 60 days.

The present invention is a method of immersing vegetables or fruits in cold water, unlike the conventional cold storage method, it is possible to manage the temperature of each storage tank differently using one freezer. When storing vegetables, the storage temperature is generally close to the freezing point (freezing temperature) of each food, but the unique storage conditions are required differently depending on the type of vegetables and fruits. For example, cabbage 0-1 degreeC, cucumber 7-10 degreeC, radish 3-10 degreeC. If different storage tanks can be managed differently, different kinds of vegetables can be stored for a long time. In the case of general refrigerated warehouses, the temperature difference between the top and bottom, left and right according to the height of the warehouse. There may be a deviation, such as a temperature difference due to the flow imbalance of the cold air due to the unbalance of the loaded state. In the case of the present invention by lowering the immersion water to the desired temperature through the heat exchanger to maintain a constant temperature in the storage tank, which is also an effective method using the thermal conductivity of water 22 to 25 times faster than air.

When storing vegetables, physiological effects such as respiration, transpiration, and locomotion occur immediately after harvesting vegetables, and the longer the storage period, the longer the storage period. In general, the concentration of oxygen in the air is high at 20-25%, but the dissolved oxygen content of water is 4-6 ppm, which is very small. In addition, by using the cold water immersion storage method of the present invention by rapidly cooling the respiratory heat caused by the physiological action of vegetables or the high temperature at the time of harvesting to a certain temperature more than the methods using the air, such as forced blowing, differential pressure, vacuum precooling It can be said that the temperature decreases evenly and quickly to the inside of the reservoir. This is the reason why you can eat warm watermelon quickly during summer in your daily life.

Vegetables contain 90 ~ 95% moisture at harvest, but maintain freshness after harvesting, so the water supply is cut off and the moisture decreases, resulting in weight loss and coarseness (withering), resulting in loss of freshness and flavor. During this time, the vegetable will not recover to its initial state if the weight loss of 5% occurs. The conventional method of storing in a refrigerated warehouse is that when the freezer is operated, it inevitably condenses the humidity in the warehouse and the moisture of the stored water, which is converted into water and discharged out of it. Decreases. However, when the immersion storage method of the present invention is used, even if vegetables have a high moisture content, the transpiration is suppressed at the optimum temperature and high humidity, and the water content of the vegetables is also slightly changed or increased slightly.

It has been investigated that there is no prior art related to the present invention.

The present invention intends to preserve the quality characteristics of vegetables and fruits produced according to the season for a long time.

The present invention, while preserving the quality characteristics of vegetables and fruits produced according to the season for a long time, by submerged storage in cold water for long-term preservation by inhibiting respiratory action, growth, transpiration and lodging as possible characteristics of the biological storage To provide a long-term storage method and storage device to maintain.

The immersion storage method of the present invention is immersed with cold water circulated in the heat exchanger, so that it is always managed constantly without a temperature difference, so that agricultural products can be stored for almost 6 months or longer, and the shipment can be adjusted, so that both producers and consumers can benefit. Can give In addition, it is possible to manage various agricultural products in different storage temperatures at different storage temperatures without temperature difference, thus providing accurate temperature management and efficient storage method.

The present invention shows the immersion storage method of agricultural products for long-term storage by setting and managing the optimal temperature of the target agricultural product storage by immersing the washed agricultural products in a loading container of a certain standard and then aligning them in an underground storage tank and immersed in heat exchanged cold water.

Immersion water exchanged in the above may include 3wt% ~ 10wt% salt.

The immersion water heat exchanged above may include 1.0 wt% to 3.0 wt% of an organic acid or sugar.

In the above, the temperature of the immersion water can be used that is -3 ℃ ~ 10 ℃.

In the above agricultural products are vegetables or fruits.

The vegetables are any one selected from radish, cucumber, cabbage, pepper or carrot.

The fruit is any one selected from apple, pear, sweet persimmon, watermelon or melon.

The present invention includes an immersion storage device for agricultural products.

In the agricultural product immersion storage device of the present invention is a cold storage device consisting of a refrigerator (10), brine tank (12), heat exchanger (13) and immersion tank (11),

And a freezer for cooling brine, a heat exchanger for exchanging the cooled brine and cold water in the submerged tank, and a submerged tank for refrigeration of agricultural products with the cold exchanged cold water.

The brine cooled to -5 ~-10 ℃ in the refrigerator can be used as a refrigerant.

Cold water in the heat exchanger may be cooled by submerged water to -3 ~ +10 ℃.

The agricultural products that can be used in the submerged storage device of the agricultural products are any one or more selected from vegetables and fruits.

The vegetables are any one selected from radish, cucumber, cabbage, pepper or carrot.

The fruit is any one selected from apple, pear, sweet persimmon, watermelon or melon.

The immersion water heat-exchanged above may include 3 wt% to 10 wt% of salt.

The present invention is composed of a submerged storage device and a storage method using the same. Immersion storage device is a pipe connecting the heat exchanger (13) installed on the side of the storage tank 11 and the cold immersion storage tank (11) for arranging one or more storage tanks of a concrete structure of a certain size in a rectangular underground space ( The immersion water heat exchanged through 50A, B) is circulated and supplied to the storage tank to keep the temperature of the storage constant.If a temperature difference occurs, the temperature sensor installed inside the storage tank detects it and sends it back to the heat exchanger to cool the immersion water. Let's do it. On the other hand, the brine of the brine tank 12 is sent to the freezer 10 through the pipe 40A to cool, and is then sent to the brine tank 12 through the connecting pipe 40B to cool the brine.

Hereinafter will be described in more detail with reference to the accompanying drawings. 1 is a block diagram of a low-temperature long-term cold water immersion storage device of the present invention, the cooling device is separated and operated in a three-step process.

The first step is to send the brine of the brine tank 12 to the freezer 10 by using the brine pump 30A to cool the brine temperature to -5 ° C ~ -10 ° C to send the repeated cycle to the brine tank 12 Form.

In the second step, the cooled brine of the brine tank 12 is sent to the cooling coil 14 in the cooling tank of the heat exchanger 13 by using the brine pump 30b to heat the immersion water to cool to 0 to + 5 ° C. Form a repeated cycle of sending the brine to the brine tank 12.

In the third step, after loading the agricultural products in the low temperature cold water immersion tank (11), the immersion water suction pipe (50A) at the bottom of the tank is sucked into the pump 31 and sent to the immersion water heat exchanger (13) 0 ~ +5 ℃ Cooling and cooling the immersion water to form a repeated cycle to spray the upper portion using the immersion water discharge pipe 50B of the upper portion of the low temperature cold water immersion tank (11).

Hereinafter, a method of storing agricultural products by immersion using the apparatus of the present invention will be described as follows.

<Inundation method of agricultural product immersion>

After arranging the fruits or vegetables to be stored in the well-drained plastic storage container, sorting them into the immersion storage tank, filling the submerged water so that the loaded agricultural products can be sufficiently submerged, and then using the pre-installed cooling device. Keep it at the lowest temperature required for preservation. At this time, if the temperature sensor is installed inside the tank and connected to the cooling device, when the temperature reaches or exceeds the set temperature, the immersion water cooled by the heat exchanger is circulated again, thereby allowing the low temperature storage at a constant temperature. After a certain period of time, if necessary, take out the agricultural product loading box by using a crane installed at the upper part of the storage tank and wash it according to the purpose.

<How to store vegetables submerged>

In storing the vegetables by operating the same method of the above-mentioned immersion storage method, radishes and cucumbers among vegetables are mostly pickled with an appropriate amount of salt and cooked as a side dish. You can save time processing and get to products quickly. In addition, the salt itself has a slight sterilizing power, but because it creates an environment in which microorganisms cannot grow, storage may be better. The osmotic effect of brine prevents the growth of microorganisms due to the escape of moisture from vegetables, and the microorganisms in the brine inhibit the proliferation of protoplasts. Therefore, the storage of vegetables is added to the storage of 6 to 7wt% of salt, the storage period is longer, the texture is also improved (texture) is improved, and does not need a separate pickling process when cooking is effective and simple cooking is possible.

<Fruit flooding storage method>

In storing the fruits by the same operation of the above-mentioned submerged storage method, pears and apples are fruits that have a shelf life because they have a good taste and have a hard skin, but after three months, Due to the evaporation of moisture, texture is worsened, so it is known that it is difficult to harvest in autumn and maintain freshness until the next spring. However, in the case of the present invention, by immersing and storing cold water at low temperature, even if the storage period is 6 months or more, it is possible to provide excellent pears and apples without affecting the quality. In particular, when measuring the sugar content and acidity of the target pear during immersion storage of the pear and stored in the immersion water of the same specific gravity has an excellent storage effect. In addition, in the case of apples, it is possible to immerse and store 1 to 3wt% salt and organic acids such as malic acid in cold water, and to add sugars and acids having the same specific gravity as apples to be stored.

Hereinafter, the content of the present invention will be described in detail through examples and test examples. However, these are intended to explain the present invention in more detail, and the scope of the present invention is not limited thereto.

<Example 1>

Fill 100kg of freshly washed radish into the storage tank one by one so that the cold water supplied through the heat exchanger can be sufficiently filled with radish. After immersion in cold water for a certain period of time, the temperature of the cold water is maintained at a preset 0 ~ 3 ℃. If the temperature sensor is installed inside the tank, the pump operates to circulate the cold water cooled by the heat exchanger. After the storage period has elapsed, take out the loading box with a crane, wash the radish, and use it according to the purpose.

<Example 2>

Salt was added to purified water instead of cold water to prepare 7wt% saline to operate in the same manner as in Example 1 to store cold brine immersion.

<Example 3>

100kg of freshly cleaned cucumbers are loaded into the storage tank one by one to fill the cold water supplied through the heat exchanger so that the cucumbers can be sufficiently submerged. After immersion in cold water for a certain period of time, the temperature of the immersion water is maintained at a predetermined 5 ~ 7 ℃. If the temperature sensor is installed inside the tank, the pump operates to circulate the cold water cooled by the heat exchanger. After the storage period has elapsed, take out the loading box with a crane, wash the cucumbers, remove the water and use it according to the purpose.

<Example 4>

Instead of cold water, salt was added to purified water, 7 wt% saline was prepared in the same manner as in Example 3, and the cucumbers were stored in cold brine immersion.

Example 5

100kg of freshly cleaned apples are loaded into the storage tank one by one, filling the cold water supplied through the heat exchanger with enough apples. After immersion in cold water for a certain period of time, the temperature of the cold water is maintained at a preset 0 ~ 3 ℃. If the temperature sensor is installed inside the tank, the pump operates to supply the cold water cooled by the heat exchanger. After the storage period has elapsed, take out the loading box with a crane, wash the apples, remove the water and pack or process.

<Example 6>

2 wt% salt and malic acid + citric acid were mixed in purified water to pH 4 and operated in the same manner as in Example 5 to store the apples in cold water.

<Example 7>

Fill 100kg of clean washed pears one by one in the storage tank and fill the cold water supplied through the heat exchanger with enough to immerse the ship. After immersion in cold water for a certain period of time, the temperature of the refrigerant is maintained at a preset 1 ° C. If the temperature sensor is installed inside the tank, the pump operates to circulate the cold water cooled by the heat exchanger. After the storage period has elapsed, the loading box is taken out by a crane, the boat is washed, and then dried and packed or processed.

<Example 8>

2 wt% of saline and 1.0 wt% of sugar were added to the purified water to make cold brine, and the vessel was immersed and stored in cold brine in the same manner as in Example 7.

Comparative Example 1

100 kg of radish was added to a saline solution prepared by adding 7 wt% of saline to purified water, and saline was immersed at 25 ° C.

Comparative Example 2

100 kg of cucumbers were added to a saline solution prepared by adding 7 wt% of saline to purified water, and saline was immersed at 25 ° C.

<Test Example>

In the same manner as in Examples 1 to 4 and Comparative Examples 1 to 2, the appearance and texture of the radish and cucumber were compared with the appearance and texture over a total of 12 times during the storage period by cold water immersion, cold saline immersion, and saline immersion. 1-1, Table 1-2, Table 2-1, and Table 2-2.

Compression test was performed to measure the texture change of cucumber and radish during storage. Samples at the upper, middle and lower ends of the sample were cut to a thickness of 1 cm and calculated as the average value of three experiments. The compressive force was Sher-Press (Food Technology Corp., Maryland, USA), and the resistance value of the sample appeared when the tissue was compressed while placing a 1 cm thick sample on an aluminum plate and moving the plunger connected to the 3000 psi ring downward. Recorded on a recorder and expressed in psi calculated from peak height.

Compression force (psi) = 3000 × (peak height ÷ 100) × (77.5 ÷ 100) × (1 ÷ 10)

Table 1-1. Changes in texture during the storage of radish

Date 0 One 3 7 10 30 Brine 245 201 200 198 197 175 cold water 245 240 235 220 210 208 Cold brine 245 241 241 239 239 236

Table 1-2. Changes in texture during the storage of radish

Date 60 90 120 150 180 210 Brine 176 175 175 170 168 161 cold water 201 196 192 188 180 178 Cold brine 235 235 234 234 233 232

Table 2-1. Changes in texture during cucumber storage

Date 0 One 3 7 10 30 Brine 160 132 120 91 84 67 cold water 160 152 150 145 140 135 Cold brine 160 154 151 149 142 140

Table 2-2. Changes in texture during cucumber storage

Date 60 90 120 150 180 210 Brine 65 60 58 55 52 50 cold water 131 128 120 116 112 108 Cold brine 138 137 136 136 135 135

From the above test results, the texture of radish and cucumber during the storage period of cold water, cold saline, and brine was measured. It can be seen that storage in cold and cold saline is much better than storage at normal temperature saline. In addition, the change in greenness was observed with time, and there was almost no change in cold water and cold brine. However, in the brine at room temperature, the greenness gradually changed and browned after 30 days.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and modified within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. It will be appreciated that it can be changed.

1 is a block diagram of an immersion cooling apparatus of the present invention.

<Description of the symbols for the main parts of the drawings>

10: freezer, 11: underground storage tank,

12: brine tank, 13: heat exchange tank,

14: cooling coil for heat exchange 20: automatic control valve,

30a, b: brine circulation pump, 31: automatic control valve (for immersion water circulation),

40A, B: brine tank / freezer connector

50a, b: immersion water circulation pipe, 60A, B: brine tank / heat exchanger circulation pipe

Claims (12)

Submerged storage method of agricultural products, characterized in that long-term storage by setting up and managing the optimum temperature of the storage of the target agricultural products by arranging the washed agricultural products in the storage tank of a certain standard and then aligning them in the underground storage tank and immersing them in the heat exchanged cold water. The method of claim 1, wherein the immersion storage of the agricultural water, characterized in that the salt containing 3wt% ~ 10wt% salt The method of claim 1, wherein the submerged heat exchange water containing 1.0wt% to 3.0wt% of organic acids or sugars immersion storage method of agricultural products, characterized in that The method of claim 1, wherein the temperature of the submerged water is -3 ° C ~ 10 ° C The method of claim 1, wherein the agricultural product is a vegetable or fruit immersion storage method characterized in that 2. The method of claim 1, wherein the vegetables are any one selected from radishes, cucumbers, cabbages, peppers, or carrots. The method of claim 1, wherein the fruits are any one selected from apples, pears, sweet persimmons, watermelons or melon. In the cold storage device consisting of a refrigerator (10), a brine tank (12), a heat exchanger (13) and an immersion tank (11), Immersion storage of agricultural products, characterized in that consisting of a chiller for cooling the brine, a heat exchanger for heat exchange the cold water of the cooled brine and the immersion tank, and an immersion tank for refrigeration of the agricultural product with the heat exchanged cold water According to claim 8, Immersion storage of agricultural products using brine cooled to -5 ~-10 ℃ in the freezer as a refrigerant 9. The immersion storage device of agricultural products according to claim 8, wherein the cold water is heat-exchanged in a heat exchanger to cool the immersion water to -3 to + 10 ° C. 9. The submerged storage device of agricultural products according to claim 8, wherein the agricultural products are vegetables and fruits. 9. The immersion storage device for agricultural products according to claim 8, wherein the heat exchanged immersion water includes salts of 3wt% to 10wt%.

Images