JP2705965B2 - Manufacturing method of red-violet dye - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a pigment for food. When producing shochu using a sweet potato cultivar, Yamakawa purple potato, or its improved varieties, its fermentation broth and
An object of the present invention is to obtain a high-grade red-purple dye industrially advantageously from a distillation residue.

(Prior Art) It is disclosed in Japanese Unexamined Patent Publication (Kokai) No. Sho 62-62 that a purple potato from Yamakawa, which is a variety of sweet potato, or an improved variety thereof is used as a raw material.
297363.

Also, obtaining food colors from various pigment-containing plants has been widely practiced. However, plants contain a large amount of impurities such as starch, proteins, sugars, amino acids, and fats in addition to pigments. Then, in a normal production method such as extraction, over-concentration and concentration, these impurities are mixed in the pigment, causing precipitation, off-flavor and off-flavor. As a method of removing the impurities, there are methods such as ultrafiltration, resin treatment, vacuum concentration, and activated carbon treatment, all of which require complicated and special equipment and labor. Activated carbon adsorbs significant amounts of useful dyes.

(Problems to be Solved by the Invention) In a conventional method for producing a natural pigment by an extraction method, a pigment raw material is extracted or purified using water, ethyl alcohol or the like as it is or after pulverization. However, this method had major industrial disadvantages. That is, one is the processing of the extracted cake. The waste which is several dozen times as large as the dye product usually obtained is waste, and the disposal cost is enormous.
The second is the deterioration of the quality of the pigment product due to the component derived from the raw material potato. That is, starch, proteins, sugars, and the like in the raw materials are extracted and mixed in a small amount into the pigment product, which causes sedimentation over time and an unpleasant taste / odor. In order to remove these impurities, the above-described complicated processing steps are required.

(Means for Solving the Problems) Fermentation using purple sweet potato from Yamakawa or an improved variety thereof as a raw material for shochu causes metabolic degradation of starch, protein, sugar and the like as impurities. And most of them could be removed. As a result, the amount of waste discharged during the dye production process is very small, and the dye purification process is also very quick and simple. With this, the present invention has achieved its purpose.

This fermentation step may be an ordinary shochu production step, but preferably the pH is adjusted to 4.0 or less. The acid used for the preparation may be a mineral acid (for example, sulfuric acid, hydrochloric acid, phosphoric acid or the like) or an organic acid (for example, citric acid, lactic acid, tartaric acid, malonic acid or the like).

Also in the distillation step, a low pH is preferable, and the pH is preferably adjusted to 3.0 or less with a mineral acid or organic acid. This is for stabilizing anthocyanin which is a pigment component of sweet potato.

(Action) Starch contained in Yamakawa purple potato and its improved varieties is first decomposed into sugar by the koji mold amylase. Next, the sugar is converted to ethyl alcohol by the yeast. That is, starch can be efficiently removed. In addition, other impurities such as proteins and fats are metabolized and reduced by the yeast. Further, a feature of the present invention is to utilize a shochu production process. This shochu moromi contains a very large amount of citric acid derived from rice koji.

This citric acid prevents the degradation of the dye during the fermentation process.
Further, by lowering the pH by adding a small amount of acid, the decomposition of the dye during the fermentation process can be further prevented. That is, the dyes contained in Yamakawa purple potato, and its improved varieties, etc., are anthocyanin dyes and exhibit a very vivid red-purple color tone.
It is unstable and decomposes at high pH above pH5. Hereinafter, the present invention will be described in detail with reference to examples.

Example 1 Washing, steaming, cooling and pulverizing 500 kg of purple sweet potato (* color value 2.1) from Yamakawa, and mixing with primary moromi prepared from 100 kg of rice, 8
Fermentation was performed for two days to prepare secondary moromi. The pH of this fermentation broth (930 l, color value 1.1) was 4.2, and almost no decomposition of the pigment was observed. After passing through the secondary mash, the mixture was concentrated under reduced pressure to obtain a dye concentrate (22.0 kg, color value 40.0). The dye solution thus obtained was clear with very few starch components.

* Color value, 10% E (λmax, 1cm) pH 3.0 Measured with McIlvaine buffer.

Example 2 Lactic acid was added to the secondary mash obtained in Example 1 described above to adjust the pH.
Is adjusted to 3.5, and then distilled with distilled spirits (1
120 l, color value 0.87). This was excessively concentrated to obtain a dye solution (19 kg, color value 40). The dye solution thus obtained was clear with very few starch components. This dye solution is subjected to the usual dye production method, that is, cutting, extraction, excess,
The quality was compared with the dye obtained by concentration.

Example 3 Duolite XAD was applied to the distilled cake excess obtained in Example 1 above.
The sugar and amino acids were washed out by adsorbing and washing with 40 l of -7 adsorption resin. The washing liquid (60 l, BOD 0.1 kg / l) was about 70% in washing liquid amount and about 30% in BOD as compared with the one that had been ground, extracted and passed through the usual raw materials. Subsequently, the dye was eluted using 30 liters of 60% ethyl alcohol, and the dye solution (4
0l, color value 13.4).

This was further concentrated under reduced pressure to obtain a dye solution (8.3 kg, color value 60.6). The dye solution thus obtained did not show any precipitation, off-flavor or off-odor after standing at room temperature for 2 months.

(Effect of the Invention) Purple potato from Yamakawa or an improved variety thereof has two characteristic useful components of starch and anthocyanin pigment. The present invention not only utilizes these useful components at the same time, but also contributes to improving the quality of the obtained red-violet dye.

Continued on the front page (72) Inventor Teruyo Muroi 1-1-11, Miwa-cho, Toyonaka-shi, Osaka Sanei Chemical Industry Co., Ltd. Examiner Chiyako Seki

Claims (2)

(57) [Claims] 1. A method for producing shochu using a sweet potato cultivar, a purple sweet potato from Yamakawa, or an improved variety thereof.
A method for producing a red-purple dye from the fermentation broth. 2. A method for producing a purple-red pigment from the distilled cake by adjusting the pH to 4.0 or less using a mineral acid or an organic acid in the fermentation broth according to claim 1 and then performing distillation. .