JPH01311174A - Purification of yellow dyestuff of gardenia - Google Patents

Abstract

PURPOSE:To simply purify the subject dyestuff free from causing color change to yellow-blue or brown in short process and high recovery by bringing an aqueous solution of yellow dyestuff extracted from Gardenia fruit into contact with an acid clay, then separating the clay, cleaning the clay with water and reacting the clay with an eluent. CONSTITUTION:An aqueous solution of yellow dyestuff extracted from Gardenia fruit is brought into contact with an acid clay and/or active clay and these clays are separated and cleaned with water or aqueous solution of alcohol. Yellow dyestuff of Gardenia fruit is desorbed from these clay by an eluent, recovered and purified. Furthermore, as the aqueous solution of alcohol for cleaning and the eluent, 5-15vol.% alcohol water solution and >=40vol.% concentrated alcohol water solution are each preferably used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a purification method for obtaining a gardenia yellow pigment that does not cause green to blue discoloration or browning phenomena.

[Prior Art] Conventionally, yellow pigments are extracted from gardenia fruits with water or alcohol aqueous solution, filtered, and then concentrated or powdered and marketed as gardenia pigment preparations, which are used in confectionery, frozen desserts, noodles, etc.
It is used in processed seafood products, side dishes, pickles, etc. When this pigment is used especially in noodles or pickles, it is known that the color changes to green or blue or browns, and the causative agent is the iridoid compound contained in the gardenia pigment extract. They are said to be glycosides and polyphenols (Japanese Patent Publication No. 52-13971, Japanese Patent Publication No. 58-277)
53).

Therefore, in order to purify gardenia pigments, that is, to remove the impurities iridoid glycosides and polyphenols, the first method uses two types of materials: a copolymer of styrene and divinylbenzene and a polyamide resin. the method of(
Japanese Patent Publication No. 58-27753) and a second method using a semi-rigid polyvinyl gel (Japanese Patent Publication No. 61-50981) were attempted.

[Problems to be Solved by the Invention] However, the first method has the disadvantage that a different adsorbent must be used for each impurity, which requires considerable time and lengthens the process. The method had the disadvantage that the adsorbent was relatively expensive.

The present invention has been made in view of the above circumstances, and
The purpose is to provide a method for purifying Chinaseed yellow pigment (crocin), which makes it possible to simultaneously remove iridoid glycosides and polyphenols using an inexpensive adsorbent.

[Means for Solving the Problem] As a result of various studies to achieve the above object, the present inventors found that acid clay, which is an inexpensive adsorbent, and activated clay obtained by activating this by acid treatment, etc. It was discovered that crocin has excellent properties for purification, and the present invention was completed.

The present invention involves contacting an aqueous solution of yellow pigment (crocin) extracted from gardenia fruit with acidic clay and/or activated clay, then separating these clays and washing them with water or an aqueous alcohol solution, and then eluating from this clay. It is characterized by the fact that it uses a liquid to desorb and recover gardenia yellow pigment.

The above alcohol aqueous solution for cleaning has a volume of 5 to 15 vol. % alcohol aqueous solution may be used, and the above eluent is 40 vol. An alcohol aqueous solution with a high concentration of % or more may be used.

[Action] By bringing the aqueous yellow pigment extracted from gardenia fruit into contact with acid clay and/or activated clay, crocin is preferentially adsorbed to the clay and the iridoid glycosides present in the gardenia fruit extract are absorbed. body and polyphenols are also adsorbed at the same time. Thereafter, the clay is separated from the aqueous dye solution and washed with water or an aqueous alcohol solution to simultaneously remove iridoid glycosides and polyphenols. Crocin can then be desorbed from the washed clay using an eluent and recovered with high purity.

The removal rate of polyphenols among impurities is higher when an alcohol aqueous solution is used as the cleaning liquid than water, but when the alcohol concentration is 15 vol. %, the recovery rate of crocin will drop sharply, so the cleaning alcohol aqueous solution should be 5 to 15 vol. % alcohol aqueous solution is preferred.

Furthermore, as the alcohol concentration of the eluent increases, the desorption rate of crocin from clay improves; %
If it is above, the desorption rate does not change much.

[Example] Hereinafter, the present invention will be explained in more detail based on examples.

Example 1 A purification treatment was performed on a yellow pigment (crocin) extracted aqueous solution having the following characteristic values, which was obtained by extraction, filtration, and concentration from gardenia fruit.

E'l? @ = 39.7 (440 nm) Absorbance at a wavelength of 238 nm, which is the maximum absorption of iridoid glycosides (
Az3a) and crocin have a maximum absorption wavelength of 440 n.
Ratio to absorbance at m (A44°) A isa / A 44G = 1, 66 Absorbance at wavelength 325 nm, which is the maximum absorption of polyphenols (Aszs), and wavelength 4, which is maximum absorption of crocin
Ratio to absorbance at 40 nm (A44°) A 32B / A aaa = 01482 5 g of crocin extraction aqueous solution, 20 g of acid clay (Mizuriki Ace #400 manufactured by Mizusawa Chemical Industry ■), and 50 ml of water were placed in a beaker and stirred for 10 minutes. After selectively adsorbing crocin, the mixture was suction-filtered using a Buchner funnel with an inner diameter of 9 cm lined with a filter cloth using a conventional method. Next, 200 ml of water was poured to wash the clay layer in the funnel. After washing, remove crocin adsorbed to the mouth soil.
Desorption was carried out by pouring 60 ml of a % ethanol aqueous solution. The desorption solution was distilled under reduced pressure to remove ethanol and concentrate to obtain 4 g of crocin solution. The characteristic values of the obtained purified crocin liquid were as follows.

E: e'+s = 46.3 (440 nm) A i,a
/ A 44° = Q, 259A321 / A440
= 0, 291 Therefore, the recovery rate of crocin, the removal rate of iridoid glycosides, and the removal rate of polyphenols based on absorbance are as follows.

Crocin recovery rate: 93.3% Iridoid glycoside removal rate: 84.4% Polyphenol removal rate: 39.6% The absorption spectra of the unpurified crocin extract aqueous solution and the purified crocin solution are shown in FIGS. 1 and 2. By comparing both figures, 2
The peak of iridoid glycosides having an absorption maximum at 38 am has almost completely disappeared, indicating that iridoid glycosides can be removed even by washing with only water without alcohol. It can also be seen that the peak of polyphenols having an absorption maximum at 325 am has been significantly reduced.

Example 2 15 vol. was used instead of water as the cleaning liquid. The same treatment as in Example 1 was carried out using 200 ml of % ethanol aqueous solution to obtain 4 g of purified crocin liquid having the following characteristic values.

E+cs =41, 0 (44,0am)Asz
a/A44°=0. 183 A sag / A”.=0.213 The recovery rate of crocin and the removal rate of impurities are as follows.

Crocin recovery rate 82.6% Iridoid glycoside removal rate 89. O% polyphenol removal rate 5
The absorption spectrum of the 5.8% purified crocin solution is shown in FIG. It can be seen that the iridoid glycoside peak has completely disappeared, and the polyphenol peak has also decreased significantly.

Example 3 4 g of the crocin extract used in Example 1, 20 g of acid clay (Mizuriki Ace #300 manufactured by Mizusawa Chemical Industry ■) 1 50 g of water
ml was placed in a beaker and stirred for 10 minutes to selectively adsorb crocin, followed by suction filtration using a Buchner funnel with an inner diameter of 9 cm lined with a filter cloth.

Then 10vol. % ethanol aqueous solution was poured to wash the clay layer. After washing, 50 vol. of crocin adsorbed on the clay layer. % ethanol aqueous solution was poured to allow desorption. The desorption solution was concentrated under reduced pressure to obtain 3 g of purified crocin solution having the following characteristic values.

E'1': m = 44.6 (440am) A23a
/ A440 = 0, 236A s2s / A
4ao = 0, the recovery rate of 249 crocin and the removal rate of impurities are as follows.

Crocin recovery rate 84.3% Iridoid glycoside removal rate 85.8% Polyphenol removal rate 4
8.3% Example 4 8 g of the aqueous crocin extract solution used in Example 1, activated clay (
40 g of Galleon Earth NS (manufactured by Mizusawa Chemical Industry ■) and 80 ml of water were placed in a beaker and stirred for 10 minutes to selectively adsorb crocin, followed by suction filtration using a Buchner funnel with an inner diameter of 9 cm lined with a filter cloth. Next, 400 ml of a 5 vol, % ethanol aqueous solution was poured to wash the clay layer. After washing, 40 vol. 100 ml of % ethanol aqueous solution was poured for desorption. The desorption solution was concentrated under reduced pressure to obtain 6 g of purified crocin solution having the following characteristic values.

At El, =46.2 (440r+m)A a3s /
A 44° = 0.269 A 5zII / A 44° = 0.278 The recovery rate of crocin and the removal rate of impurities are as follows.

Crocin recovery rate 87.3% Iridoid glycoside removal rate 83.8% Polyphenol removal rate 4
2.3% [Test Example] To 1 kg of wheat flour, unpurified crocin extract aqueous solution and purified crocin liquid obtained in Examples 1 to 4 were diluted with water, and E='
Liquid 450 adjusted to rjm 0.04 (440am)
Add 10g of table salt or a solution of 10g of table salt and 5g of powdered Gansui to m1, make Chinese raw noodles by the usual method,
The sample was stored in a constant temperature bath at ℃ for 48 hours, and changes in color tone were observed.

The results are summarized in Table 1. In the plots to which the unpurified crocin extract was added, there was a change in color in both the plots with and without the addition of kansui, but no change in color was observed in the plots in which the purified crocin extract of Example was added.

(The following is a blank space) [Effects of the Invention] Although the method for purifying gardenia yellow pigment of the present invention is constructed as described above, and cheap acid clay and/or activated clay is used as an adsorbent, Since the iridoid glycosides and polyphenols, which are impurities contained in the gardenia yellow pigment extract, can be removed at the same time, it is possible to easily remove the iridoid glycosides and polyphenols contained in the gardenia yellow pigment extract. A pigment (crocin) can be obtained.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are absorption spectra of the unpurified aqueous crocin extract solution and purified crocin liquid in Example 1.2. Patent Applicant Toyotama Fragrance Co., Ltd. 53 Figure 1 North Example 2 4 Kan 1 Compliance 1 Deaf” Warrant Suherit 1 Procedural Amendment 1. Description of the case 1986 Patent Application No. 140838 2 Title of the invention Method for purifying gardenia yellow pigment 3 Relationship to the case by the person making the amendment Patent applicant Address Title Toyotama Fragrance Co., Ltd. 4 Agent As per attached sheet. [Contents of amendment] (1) In the specification, page 1, line 19, "constant temperature layer" is corrected to "constant temperature bath." (2) In the first line of page 11 of the same book, "extract liquid" is corrected to "extract aqueous solution." (3) Table 1 on page 12 of the same book is amended as follows. (Margin below)

Claims (2)

[Claims] (1) After bringing the yellow pigment aqueous solution extracted from gardenia fruits into contact with acidic clay and/or activated clay, these clays are separated and washed with water or an aqueous alcohol solution, and then the gardenia yellow color is obtained from this clay using an eluent. Desorbs dye,
A method for purifying gardenia yellow pigment, the method comprising recovering gardenia yellow pigment. (2) The alcohol aqueous solution for cleaning is 5 to 15 vol. % alcohol aqueous solution, and the eluent was 40 vol. The method for purifying gardenia yellow pigment according to claim (1), which is an aqueous alcohol solution with a high concentration of % or more.