JP2005245243A - Method for denitrogenation of vegetable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for denitrogenation of vegetables enabling easy reduction of nitrate-nitrogen contained therein. <P>SOLUTION: This method for denitrogenation of vegetables comprises irradiating vegetables with light during night within at least two weeks before harvest with no fertilization and/or a term within one week after harvest to reduce nitrate-nitrogen; or preferably comprises applying a reducing agent at least two weeks prior to harvest with no fertilization. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a denitrification method for vegetables, and more particularly, to a denitrification method for vegetables that can reduce nitrate nitrogen in vegetables by a simple method.

In recent years, vegetable juice powder has attracted attention against the background of the health boom. Under such circumstances, as a method of producing vegetable juice powder that is effective in maintaining health, such as by preventing the aging of blood vessels, by removing nitrate nitrogen, which is a harmful substance, washing when washing, freeze-drying, and pulverizing vegetables There has been proposed a method for producing vegetable juice powder characterized by using water from which nitrate ions and nitrite ions have been removed with an ion exchange resin (see, for example, Patent Document 1).
JP-A-10-229858

  By the way, in the vegetable production method, since nitrogen fertilizer is absorbed and used by the vegetable as nitrate nitrogen, nitrate nitrogen may be deposited on the harvested vegetable although it is traced. Therefore, reduction of nitrate nitrogen in vegetables is desired not only in the case of juice as a concentrate but also in general edible use.

  This invention is made | formed in view of the said situation, The objective is to provide the denitrification method of vegetables which can reduce the nitrate nitrogen in vegetables by a simple method.

  That is, the gist of the present invention is that a vegetable is characterized in that nitrate nitrogen is reduced by irradiating the vegetable with light at least for 3 days at night and / or within 1 week after harvest. It exists in the denitrification method.

  According to the present invention, nitrate nitrogen in vegetables can be reduced by a simple method, and in particular, vegetable juice effective for maintaining health can be produced.

  Hereinafter, the present invention will be described in detail. The vegetables to be subjected to the denitrification method of the present invention are not particularly limited, and may be any of fruit vegetables, leaf stem vegetables, and root vegetables.

  Specific examples of fruit vegetables include tomato, eggplant, bell pepper, cucumber, pumpkin, watermelon, melon, pea, green beans, green beans, broad beans, corn, okra, strawberry and the like.

  Leaf and stem vegetables include cabbage, broccoli, cauliflower, brussels sprouts, arugula, Chinese cabbage, pine nuts, komatsuna, nozawana, kale, lettuce, sunny lettuce, salad na, spring chrysanthemum, fuki, chicory, mugwort, salad vegetables, celery, celery, Parsley, ashitaba, trefoil, mushroom, shiitake, matsutake, onion, leek, bamboo shoot, leek, garlic, raccoon, esha, lot, chives, asparagus, perilla, basil, spinach, udo, taranome, bamboo shoot, spring, bracken, Examples include sprouts and ginger.

  Examples of root vegetables include burdock, sweet potato, urine, potato, radish, radish, turnip, wasabi, carrot, beet, lotus root, ginger and the like.

  Among the above-mentioned vegetables, tomato, cabbage, Chinese cabbage, Chinese cabbage, komatsuna, spring chrysanthemum, mugwort, salad vegetable, celery, parsley, trefoil, asparagus, spinach and carrot are preferred from the viewpoint of use for vegetable diuse.

  By the way, the production of vegetables is carried out by growing after seeding or transplanting and harvesting at an appropriate time. As fertilizers, natural fertilizers or chemical fertilizers are applied as raw fertilizers, additional fertilizers and the like. Such a production method is performed by a conventional method established according to the type of vegetable.

  In the present invention, the vegetables are irradiated with light for at least 3 days in the non-fertilized state before harvesting and / or for a period of 1 week or less after harvesting. Before harvesting, it is a state of no fertilization, but the vegetables maintain a sufficient freshness, and after harvesting, the freshness of the vegetables gradually decreases. The majority of nitrate nitrogen in vegetables is removed by light irradiation before harvesting, and the remaining nitrate nitrogen is removed by light irradiation before harvesting. The light irradiation before harvesting is preferably at night for 5 days, and usually at night within 2 weeks. Moreover, the light irradiation before harvesting is preferably 1-3 days. The optimal light irradiation time (period) varies depending on the illuminance of the light to be irradiated, and is thus determined appropriately in consideration of the illuminance of light and the target degree of denitrification. For example, in the case of leaf and stem vegetables such as spinach, the light irradiation after harvesting is preferably performed by immersing the root in water. By such an aspect, it is possible to effectively suppress a decrease in freshness.

  In the present invention, the light source used for light irradiation is not particularly limited, but can be irradiated with a wavelength close to sunlight (natural light) used in the field of artificial cultivation known as a plant factory or vegetable factory. Various light sources can be used. Examples thereof include incandescent bulbs, fluorescent lamps, high pressure sodium lamps, metal halide lamps and the like. Moreover, the illumination intensity of the light with respect to irradiated vegetables is 300 lux or more normally, and the upper limit is 5000 lux normally.

  Moreover, in this invention, it is preferable to apply a reducing agent at least 2 weeks before the non-fertilization state before harvest. The reducing agent is typically sucrose (sucrose), but is not limited thereto, and may be maltose (malt sugar), polysaccharides, or these saccharide-containing waste liquids. Thereby, the reduction | restoration of soil advances and the reduction effect of the nitrate nitrogen amount in vegetables is anticipated. In particular, the effect can be expected in the case of leaf and stem vegetables such as spinach. The application of the reducing agent performed in the non-fertilized state is usually made within 2 months.

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded.

Example 1:
In a 3m wide and 11m long open type test house, a field consisting of two shores with a ridge width of 0.95m and a length of 10m (0.5m between shores) is formed. A total of six incandescent bulbs (100w) are installed at a height of 1m in the center of the side of the direction, and about 50 (about 500 per carn) ginseng are cultivated and harvested within a 1m shore length. Light was irradiated during the night from harvesting for 2 weeks until harvest. During the daytime, the ceiling of the house was opened for natural cultivation, and the illuminance of the light irradiated at night was 600 lux.

  After harvesting, nitrate nitrogen was measured on 10 carrots at random in the following manner. That is, the carrot sample was crushed with a juicer, and the nitrate nitrogen of the juice separated from the solid content was measured with a commercially available nitrate nitrogen measurement kit (“RQ Flex Plus” manufactured by Kanto Chemical Co., Inc.). Evaluation was made with the average of the measured values for 10 carrots. As a result, the blank value that was not irradiated with light (average value of the measured values for 10 carrots) was 320 ppm, whereas it was reduced to 100 ppm when irradiated with light.

Example 2:
In a container containing water, 50 spinach plants just after harvesting were put so that the roots were soaked in water, and light was irradiated from the height of 1 m above the spinach for a whole day and night. The illuminance of light was 600 lux. The same incandescent bulb as in Example 1 was used as the light source. Nitrate nitrogen in the leaves of spinach was measured in the same manner as in Example 1. For the measurement, 50 spinach plants were used as they were. As a result, the blank value that was not irradiated with light (average value of the measured values for 10 spinach plants) was 2300 ppm, whereas it was reduced to 600 ppm when irradiated with light.

Claims (5)

  A method for denitrifying vegetables, comprising reducing the nitrate nitrogen by irradiating the vegetables with light for at least 3 days in the non-fertilized state before harvesting and / or for a period of up to 1 week after harvesting.   The denitrification method according to claim 1, wherein the light has an illuminance of 300 lux or more.   The denitrification method according to claim 1 or 2, wherein the vegetables are root vegetables.   The denitrification method according to any one of claims 1 to 3, wherein the vegetable is carrot.   The denitrification processing method according to any one of claims 1 to 4, wherein the reducing agent is applied at least two weeks before the non-fertilization state before harvesting.