JP5649624B2 - Manufacturing method of pickled eggplant - Google Patents

Description

  The present invention relates to a method for producing eggplant pickles and eggplant pickles. More specifically, the present invention relates to a method for manufacturing eggplant pickles that can significantly prevent the color fading of eggplants due to pickles and eggplant pickles.

  Vegetables become easier to eat and improve the taste. However, when the vegetables are cut, the tissue is destroyed, the components are changed, and the appearance is deteriorated due to fading or browning. In addition, the texture changes due to cooking, and the mouthfeel changes, or the pigment is decomposed and discolored. In general, the pigment contained in eggplant peel is unstable and easily oxidized and decomposed by heat, light, pH, etc., and easily fades or discolors. In particular, sugar beet is often placed in a transparent container where the contents can be seen, and if it is exposed to the light of a fluorescent lamp for a long time, it will fade and the product value will be significantly reduced. This fading causes problems such as reducing the consumer's willingness to purchase.

When raw eggplant is physically damaged or affected by microorganisms, the tissue of that part fades, which is due to enzymatic browning. The browning phenomenon when raw eggplant is cut is also due to enzymatic browning. This enzymatic browning is known to fade due to oxidation of the phenolic substance contained in eggplant by polyphenol oxidase (polyphenol oxidase).
Nasnin, which is a representative pigment of eggplant, is a delphinidin-based pigment and is water-soluble, so when it is boiled as it is, this pigment is eluted from eggplant. However, by heating the edible oil to around 180 ° C. and performing “fried”, it is possible to inactivate polyphenol oxidase contained in the skin, at the same time as making the flesh soft and easy to eat, It also leads to a kind of fading prevention. However, this method can hardly prevent fading due to light after cooking.

Taking advantage of the deep purple color unique to eggplants is the main point of cooking eggplants, such as adding alum and nails to eggplant pickles. It is also important to avoid heating for a long time, and when making miso soup, it is recommended to finish with miso as soon as possible (Non-Patent Document 1). As a means for applying alum to pickled eggplants and preventing eggplant fading, a method of frying raw eggplant after being immersed in alum has been proposed (Patent Document 1). However, the use of alum is not preferable because the color of eggplant changes from purple to dark blue and the original color of eggplant is lost.
In addition, methods using synthetic dyes such as Red No. 2, Red No. 3, Red No. 40, Red No. 102, Red No. 104, Red No. 105, Red No. 106, Blue No. 1, Blue No. 2, etc. are also employed. However, it is preferable to use a natural product, and the use of this natural product is consistent with consumer preferences in recent years.

Japanese Patent Laid-Open No. 2-9338 New edition Japanese Food Encyclopedia, pages 374-375, published by Ishiyaku Shuppan Publishing Co., Ltd., February 25, 1982, first edition

  The object of the present invention is to provide a method for producing eggplant pickles and eggplant pickles that can prevent the fading of eggplants due to pickles, which is safe and economical, in view of the problems of the prior art described above. It is in.

To summarize the present invention, the first invention of the present invention is a raw eggplant having a polyphenol content of 15.
It is soaked in bran pickles, bran pickles or mustard pickles characterized by being immersed in anti-fading material for pickled eggplants containing black rice extract having an anthocyanin content of 5.0% or more as an active ingredient. The present invention relates to a method for manufacturing a pickled eggplant. A second invention of the present invention relates to a pickled eggplant obtained by the production method described in the first invention.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have made raw eggplants by using eggplant fading prevention materials containing black rice extract as an active ingredient to produce eggplant pickles. It was confirmed that it was effective in preventing discoloration in eggplant pickles such as pickled rice bran or pickled mustard.

  The eggplant discoloration-preventing material of the present invention contains a polyphenol-containing product and / or rice bran enzyme degradation product, for example, a seasoning liquid, soaking raw eggplant in this seasoning liquid, and cooking by heating, or By cooking while immersed, the fading of eggplant can be suppressed and fading can be suppressed even after light irradiation. Furthermore, by using the seasoning liquid, it is possible to obtain an eggplant processed food in which the fading of eggplant after the heat cooking process is suppressed during the heat cooking process. For preventing color fading in eggplant pickles that are not cooked, an anti-fading material for eggplant pickles, in which the polyphenol-containing material contains black rice extract as an active ingredient, is useful.

Hereinafter, the present invention will be specifically described.
Eggplant is a solanaceous plant, and the skin color is purple to black purple, yellowish green, white, etc., but in the present invention, it is particularly suitable for preventing fading of purple to black purple eggplant. Depending on the form of the fruit, it is classified as round, oval, long oval, medium long, long, or large, and there are various varieties and production areas, but there is no particular limitation.

Polyphenols are purple black rice, black rice, red rice, black beans, red grapes, blueberries, red cabbage and other pigment ingredients, grapefruit bitterness ingredients, tea astringency ingredients, tea pigment ingredients, tannins contained in astringents, and other molecules. It is a substance that contains several phenolic hydroxyl groups and is a general term for these compounds.
Polyphenols can be broadly classified into monomer types and polymer types. Representative monomer types include a group of compounds called flavonoids, chlorogenic acid and ferulic acid contained in coffee and the like, and similar compounds thereof. On the other hand, the polymer type includes tannin. Tannins are classified into condensed tannins and hydrolyzed tannins.
Many vegetables such as strawberry, red cabbage, red grape, anthocyanin pigment that is a pigment component such as purple potato and hibiscus flowers, turmeric pigment component, naringin that is a bitter component of grapefruit, and vitamin P, such as buckwheat, azuki bean, citrus These substances are all flavonoids such as rutin contained in fruits, hesperidin contained in Unshu mandarin oranges, catechins that are astringent components of tea, and pigments of black tea. More than 4000 compounds are known, but most of them exist as glycosides, and rarely exist in a free state except for catechins contained in tea etc. [FFI JOURNAL] , Vol. 209, no. 5, p. 441-446, 2004].

The eggplant discoloration prevention material of the present invention is characterized by containing a polyphenol-containing material and / or a rice bran enzyme degradation product. Those that contain a large amount of polyphenols are very effective in preventing eggplant fading. It is important to extract polyphenols efficiently from polyphenol-containing materials. Among the polyphenols, anthocyanins, which are glycosides having anthocyanidins as aglycones, are particularly suitable.
The polyphenol-containing material in the present invention includes those containing the above-mentioned polyphenol, for example, grape, purple black rice, black rice, red rice, black beans, rosemary, cassis, blueberry, elderberry, litchi, pomegranate, beer extract, cacao, chlorogen Acid, Eucalyptus, Glycosyl Rutin, Grape Seed, Cranberry, Soy Isoflavone, Mint, Pine Bark, Evening Primrose, Guava Leaf, Buffalo, Olive, Coffee Bean, Perilla, Rutin, Yuzu, Kiwi, Rose Petals, Red Ginger, Bilberry, Myricitrin , Apple polyphenol, isoquercitrin, monoglucosyl hesperidin, and the like, or the processed products such as those obtained by squeezing fruit juice as an example. There is no limitation on the shape of the workpiece, and examples thereof include granular, powder, paste, and liquid. There is no particular limitation on the processing method of the polyphenol-containing material, and examples thereof include a method in which black rice is ground finely with a mortar or the like and pulverized.
Among the polyphenol-containing materials, grapes, black rice, black beans, rosemary, cassis, blueberries, elderberries, beer, lychee seeds, kiwi seeds, grape seeds, red wine, cacao are preferred examples. Furthermore, alcoholic beverages containing a large amount of polyphenols such as wine and fruit wine may be used.
In particular, fruit juice having a large anti-fading effect on eggplant is in the order of cassis fruit juice, blueberry fruit juice, and grape fruit juice, and these have a polyphenol content of 1,000 mg / kg or more. In addition, the black bean aqueous extract is almost colorless regardless of its anthocyanin content, and is effective in preventing the fading of eggplants. It is presumed that it works effectively in some way.

The rice bran in the present invention may be any rice bran generally called red rice bran (milled rice ratio of about 90%), tiger rice bran (milled rice ratio of about 90 to 80%), and white rice bran (milled rice ratio of about 80% or more), There is no particular limitation on the type and variety of rice. In the present invention, for example, a rice bran enzyme decomposition product obtained by performing enzyme treatment of rice bran with amylase, protease or the like may be used.
The rice bran raw material used in the present invention may be rice bran itself, or defatted rice bran obtained by removing oil and fat components with hexane or other solvent. The rice grain surface layer is rich in many components such as proteins, vitamins, oils and fats, and inorganic substances, and these substances also contain substances that are effective in preventing eggplant fading, so rice bran that does not degrease is preferable. . By using in combination with a polyphenol-containing material, eggplant fading can be prevented synergistically.

The aforementioned polyphenol-containing product and / or rice bran enzyme degradation product may be further used as an extract.
The extraction method is not particularly limited, and examples thereof include a hot water extraction method and an organic solvent (for example, ethanol) extraction method. The extraction conditions may be appropriately selected in consideration of work efficiency and the like, and treatments such as enzymatic decomposition, concentration, decolorization, deodorization, and drying can be performed as necessary.
There is no particular limitation on the form of the eggplant discoloration-preventing material of the present invention, for example, powder, granules, tablets, liquids, emulsions, pastes, etc. What is necessary is just to use it disperse | distributing to a liquid etc.

An example of the method of using the eggplant discoloration prevention material of the present invention is shown below.
The “heat cooking” of the present invention refers to a process such as baking, boiling, steaming, and frying.
First, eggplant dipping treatment is performed. The raw eggplant is brought into contact with an immersion liquid containing the eggplant discoloration prevention material of the present invention. As long as the whole eggplant is immersed in the immersion liquid, or if it is a partly immersed amount, the position of the eggplant may be changed from time to time so that the whole eggplant is in contact with the whole. However, since the dye may be eluted from the eggplant when the immersion time is long, the immersion time is preferably about 30 minutes to 17 hours. For example, when immersed at a temperature of about 5 ° C., the immersion time is lengthened. When immersed at a temperature of about 25 ° C., the immersion time may be about 3 to 6 hours, and the immersion time is appropriately selected. Just do it. The eggplant after the immersion is taken out of the immersion liquid, and then the immersion liquid adhering to the eggplant surface is immediately wiped off and cooking is performed for a short time. What is necessary is just to perform heating temperature at the temperature at the time of general frying, 160-200 degreeC. For example, in the case of 180 ° C., the heating time is preferably about 1 to 5 minutes. If the heating time is too short, the eggplant will not be soft until now, so it is desirable to appropriately select the heating time while checking the texture. Moreover, since it will accelerate | stimulate fading of eggplant according to a cool-down time if it cools as it is, it is more preferable to cool rapidly after cooking. In this case, if it is immersed in a seasoning liquid for seasoning eggplant cooled to about 5 to 10 ° C., it is advantageous because the eggplant can be cooled while seasoning.

On the other hand, cooking with raw eggplant immersed in an immersion liquid is also effective for preventing eggplant fading.
After the immersion liquid containing the eggplant fading preventing material of the present invention has boiled, raw eggplant is added to the immersion liquid and boiled for about 1 to 10 minutes. When boiling for more time than this, fading of eggplant by heat will be promoted. In addition, when cooking is performed with the eggplant immersed in the immersion liquid, the eggplant temperature gradually rises, and the polyphenol oxidase contained in the eggplant is activated before the immersion liquid reaches the boiling temperature. Therefore, it is important to cook by heating after the immersion liquid has boiled. Also in this case, as in the case of the above-mentioned frying, the fading of eggplant can be prevented by cooling immediately after cooking.

  The addition amount of the eggplant discoloration prevention material of the present invention may be appropriately set according to the composition of the polyphenol-containing material and / or the rice bran enzyme degradation product-derived component, and is not particularly limited. Depending on the type of polyphenol-containing material used, solubility and discoloration-preventing effect are different, so it cannot be determined unconditionally. Use is preferred. It should be noted that the higher the concentration of the eggplant discoloration prevention material, the greater the effect of preventing eggplant discoloration.

As a method for evaluating the degree of color fading of eggplant peel, color measurement (Hue, Value, Chroma) (Hue, Value, Chroma) of the eggplant peel irradiated with light after cooking is performed using a spectrocolorimeter. went. When the colorimetry is performed using the spectrocolorimeter, it is digitized as three attributes of the Munsell color system, that is, hue (Hue), lightness (Value), and saturation (Chroma).
Hue (Hue) is an attribute that distinguishes color quality, and five colors of red (R), yellow (Y), green (G), blue (B), and purple (P) are the main hues. Yes. A ring drawn according to the circulation of the color is called Munsell's hue ring, and intermediate hues such as PB (purple blue) and RP (red purple) are provided between the five major hues, and there are 20 kinds of hue scales. And numbers 1 to 10 respectively.
The degree of lightness and darkness of the color is called lightness (Value), and it is divided into 10 levels, with achromatic black without light at the bottom and its value as 0, and white as the contrast at the top and 10 .
Saturation (Chroma) is a property indicating the degree of “brightness”.
The color of eggplant has a large individual difference, and it is difficult to indicate specific target values of three attributes relating to fading prevention. However, when fading due to heat or light, the hue of eggplant changes from a hue close to purple (P) to a hue close to red (R) in accordance with the cyclic transition of the Munsell hue ring. For example, in the Munsell hue, 5P-6P-7P-8P-9P-10P gradually increases from reddish purple to red, and then 1RP-2RP-3RP-4RP-5RP-6RP-7RP-8RP-9RP. The hue changes to red in the order of −10 RP. Also, the brightness value tends to increase with fading. A specific color is expressed by three attributes obtained by adding saturation to the hue and lightness.
In the present invention, it can be evaluated that fading is prevented when the hue shows a value within the range of P (purple), or when the hue shows a lower value of RP (red purple). When the hues are close, the value of brightness is further referred to, and it may be evaluated that the color with low brightness is prevented from fading.
In addition, what is necessary is just to perform the conditions of light irradiation for 3 hours on the conditions of illumination intensity 13,000 lux (lx) and 20 degreeC, for example.
By using the eggplant discoloration preventing material of the present invention, it is possible to obtain eggplant processed foods such as eggplant boiled and eggplant tempura, in which the color fading of the eggplant after the heat cooking process is suppressed during the heat cooking process.

  The eggplant fading prevention material of the present invention can significantly prevent eggplant fading due to heat and light, but is also a useful fading prevention material for eggplant pickles that are not cooked. As an anti-fading material for eggplant pickles, it is preferable to contain black rice extract as an active ingredient among polyphenol-containing materials. Black rice extract is an extract of black rice (a kind of ancient rice native to Hanzhong Province, Shaanxi Province, China, also called purple black rice or purple rice), and preferably has excellent solubility in water. Purple black powder Black rice extract-P and black rice extract-PC [both manufactured by Oriza Oil Co., Ltd.], which are water-soluble, are preferable examples. The black rice extract-P and black rice extract-PC have a product standard of a polyphenol content of 15.0% or more and an anthocyanin content of 5.0% or more. The pickles are suitable for pickled rice bran pickles, pickled rice bran pickles and pickled mustard. Although it may be used for soaking, it is particularly suitable for fermentation by a bran bed. The raw eggplant may be immersed in an aqueous solution containing, for example, 0.1 w / w% black rice extract and then immersed in a previously prepared bran floor. Other applications include application to eggplant salad.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

  100 g of an aqueous solution containing 0.1 w / w% of black rice extract-P [manufactured by Oriza Oil Co., Ltd.] was prepared, one raw eggplant was added, and immersed for 3 hours at room temperature. Lightly wipe, cut in half in the vertical direction, and cut into a commercially available bran pickles (made by SBI Foods Co., Ltd.) consisting of rice bran, salt, spices, fragrance and thickening polysaccharide as raw materials. It was immersed for 3 days at ° C. (Invention 1). As a control, the raw eggplant was cut in half in the longitudinal direction without being immersed in the liquid, and was similarly immersed in bran pickles (Control 1). For each, using a light stability tester PT-400NC (manufactured by Nippon Medical Instruments Co., Ltd.), light irradiation was performed for 3 hours under conditions of illuminance of 13,000 lux and 20 ° C. The chromaticity of eggplant peel was measured. The chromaticity was measured with a spectrophotometer, a spectrophotometer CM-3500d (manufactured by Minolta Co., Ltd.). The results are shown in Table 1.

  From the results in Table 1, although slightly yellow (Y) hue was observed, the fading of eggplant was prevented in the present invention 1 (hue 2.26 YR) than in the control 1. Since the hues are the same YR, the brightness value is compared with 2.53 for the control 1 and 1.70 for the present invention 1 to prevent fading. Since it looks good even if it is lined up on a shelf of a supermarket or a convenience store, it has been found that the anti-fading material for pickled eggplants containing the black rice extract of the present invention is useful.

  Eggplant mustard pickles were prepared using small eggplants. Except for using small eggplants, that is, small raw eggplants, soaking was performed under the same conditions as in Example 1, and soaking for 3 days in a soaking bed mainly composed of Japanese pepper. The resulting eggplant pickled in eggplant had a vivid eggplant skin color, good compatibility with the color of mustard, and was also visually pleasing.

  By using the eggplant discoloration-preventing material of the present invention containing a polyphenol-containing material and / or rice bran enzyme degradation product, it is possible to prevent eggplant discoloration due to light in particular. The polyphenol-containing material and / or rice bran enzyme degradation product to be used is a material with safety and economy, and it is possible to obtain an eggplant processed food in which fading after heat cooking is suppressed during the heat cooking of eggplant. In particular, the anti-fading material containing black rice extract is also a useful anti-fading material for eggplant pickles that are not cooked. The present invention is useful because it can contribute to prevention of product quality deterioration.

Claims (2)

Rice bran immersed in an anti-fading material for pickled eggplants containing black rice extract having a polyphenol content of 15.0% or more and an anthocyanin content of 5.0% or more as an active ingredient The manufacturing method of the pickled eggplant which is pickled, stuffed with soup or pickled in mustard . Eggplant pickles obtained by the production method according to claim 1 .