JPH0643445B2 - Pectin manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing pectin.

Pectin is a colloidal cell wall polysaccharide widely distributed in the plant kingdom and is mainly composed of α-1,4 bond of D-galacturonic acid as a substance useful for filling cells and supporting tissues. It contains neutral sugars such as arabinose, galactose and rhamnose in various proportions. Particularly, citrus peels such as lemons, limes, oranges, and grapefruits, apples, and the like contain a large amount of high-quality pectin, and pectin is produced using these as a raw material in Western countries. The carboxyl group of D-galacturonic acid in the pectin molecule is partially methyl-esterified. High methoxyl (HM) pectins with a methoxylation degree of 50% or more, and low methoxyl (LM) pectins with a methoxylation degree of 50% or less. Is classified as. These have different gelation mechanisms and gelation conditions, but their pectin levels are low.
Utilizing the property of forming a stable gel in the pH system and the property of acting as a protective colloid in the low pH system,
It is widely used in the food industry as a jam, marmalade, jelly confectionery, fruit juice drink, yogurt, etc.

The general method for producing pectin from citrus peel and the like is as follows. The pericarp is washed several times with cold water and / or warm water to remove water-soluble substances such as sugar, organic acid and pigment in the pericarp, and then pectin is heated and extracted with an inorganic acid such as hydrochloric acid and sulfuric acid. Insoluble matter is separated from this extract by centrifugation, compression separation, etc., and a super-auxiliary agent such as diatomaceous earth is added to the separated solution for clarification. The resulting excess liquid is concentrated to add a water-miscible organic solvent such as methanol, isopropyl alcohol, or acetone, or a metal salt such as aluminum, copper, or iron is added to precipitate pectin as the metal salt, Dehydrate and collect. In the case of the metal salt method, it is necessary to subsequently wash the precipitate with acidic alcohol or the like to remove the metal content and solubilize it. In either case, the pectin precipitate is dried and ground into powder pectin.

The biggest problem in such a general pectin production method is the low extraction concentration of pectin. The ratio of pectin contained in dried pectin raw material peels is not constant depending on the type of raw material, production area, harvest time, etc.
It is said to be about 20%, and when extraction is performed, the undissolved residual portion is overwhelmingly larger than the pectin content. When, for example, centrifugation is used as a method for separating the undissolved residue, the solid content concentration of the separated residue is low, and thus the higher the concentration of the extract, the lower the yield of the separated solution. For example, when the concentration of the extract is 1%, the yield of the separated liquid is about 75%, whereas when the concentration is about 1.5%, the yield of the separated liquid is reduced to about 50%, which is disadvantageous. With unpredictable results. When the residual separation is carried out by the compression method, the insoluble content is extremely soft, slippage occurs, sufficient compression cannot be performed, and the solid content concentration of the residual does not increase,
The screen is easily clogged.

Under the circumstances, according to the conventional pectin production method, the pectin concentration limit is at most 1%,
If it is higher than this range, the efficiency is lowered due to the difficulty of separating the insoluble residue. However, handling a low-concentration solution is not economical because it requires an enormous amount of alcohol, as in the case of recovering pectin by the alcohol method. It is not preferable in terms of sex.

The object of the present invention was to provide a method for efficiently producing pectin by increasing the extraction concentration of pectin.

The present invention relates to an extract obtained by extracting pectin from a pectin-containing plant or an insoluble matter separated from this extract, and a pressing aid in an amount of 30 to 20 per 100 parts by weight of the insoluble matter.
This is a method for producing pectin, which comprises adding 0 parts by weight, pressing to separate insoluble matter, and then clarifying and filtering the separated liquid (pressed liquid) by a conventional method.

According to the present invention, by adding and mixing the pressing aid to the extract of pectin, the insoluble matter is hardened to facilitate the pressing, and the flow path of the pressing liquid is secured to prevent clogging of the screen. It is possible to efficiently collect the liquid without causing it.

As the squeezing aid, diatomaceous earth, perlite, a super-helping agent such as cellulose or sawdust, fir shells, washed water of insoluble residue of pectin and the like can be used, but in the sense of hardening the insoluble residue, cellulose, Ogre scraps and fir shells are especially effective, and diatomaceous earth, from the meaning of preventing clogging of the screen,
A super-auxiliary agent such as perlite is particularly effective. Therefore, in the actual use, it is also advantageous to use these by appropriately mixing them so as to be compatible with the system.

The addition amount of the pressing aid is preferably determined in proportion to the amount of insoluble matter, that is, the concentration of pectin, and although it depends on the type of the additive and the pectin manufacturing raw material, the absolutely dry insoluble matter is 100%.
Generally, 30 to 200 parts by weight is suitable for parts by weight.
If the amount added is too large, the recovery rate of the liquid is lowered, which is not preferable. On the contrary, if it is too small, sufficient pressing cannot be performed. As a method for adding the additive, it is usually added at the time of extraction, but it may be added to the extract, or the additive may be mixed with the separated insoluble matter separated by centrifugation or the like and squeezed. Good. As the squeezing device, a usual device such as a screw press or a roller mill is used.

Example 1 1.5 kg of a dried product of summer orange juice was washed with water, added to water, adjusted to a total amount of 20 kg, adjusted to pH 2.0 with hydrochloric acid, and stirred at 90 ° C. for 30 minutes for extraction. The insoluble matter in the bone dry is about 900 g. Next, the extract was squeezed using a squeezing aid in which 70 g of diatomaceous earth super-assistant and 400 g of cellulose super-assistant were mixed, and 3.3 kg of insoluble residue and juice 17.
I got 1 kg. 0.5% of diatomaceous earth assisting agent was added to the juice and clarification was performed. Isopropyl alcohol was added to the obtained liquid to a concentration of 60% to separate the precipitated pectin precipitate, which was dried and ground. Powder pectin 22
0 g was obtained. Yield of product pectin based on the raw material skin is 1
It was 4.7% and the pectin concentration of the extract was 1.40%.

Example 2 1.5 kg of the dried product of lemon juice was washed with water and extracted in the same manner as in Example 1 to obtain an extract solution containing 850 g of insoluble matter, which was completely dried.
As a pressing aid, 500 g of a cellulosic super-auxiliary agent was added and pressed to obtain 2.6 kg of an insoluble residue and 17.9 kg of juice. Clarification, dehydration, drying and pulverization were carried out in the same manner as in Example 1 to obtain 275 g of powdered pectin. The yield of the product pectin based on the raw material peel was 18.3%, and the pectin concentration of the extract was 1.75%.

Example 3 2 kg of dried dried dried tangerine peel was washed with water and extracted in the same manner as in Example 1, and 200 g of a cellulose super-assisting agent and 800 g of fir shell as a pressing aid were added to the extract and insoluble by pressing. A residue of 3.5 kg and a juice of 17.5 kg were obtained. Example 1 below
Clarification, dehydration, drying and pulverization were carried out in the same manner as in 1. to obtain 256 g of powdered pectin. The yield of the product pectin based on the raw material skin was 12.8%, and the pectin concentration was 1.83%.

Comparative Example 1 1 kg of dried dried tangerine peel was washed with water and extracted in the same manner as in Example 1, and the extract was centrifuged without adding a pressing aid to obtain 4.6 kg of a residue and 15.4 kg of a separated liquid. It was Clarification, dehydration, drying and pulverization were carried out in the same manner as in Example 1 to obtain 140 g of powdered pectin. The yield of the product pectin based on the raw material peel was 14.0%, and the concentration of the extract was 0.93%. In this case, the yield is good, but the extract is low in concentration, which is not preferable in terms of pectin production cost.

Comparative Example 2 1.5 kg of dried lemon juice peel was washed with water and extracted in the same manner as in Example 1, and the extract was squeezed without adding a squeezing aid to obtain 1.4 kg of insoluble residue and juice of 18.6. I got kg. Since the amount of insoluble matter in the squeezed juice was large and it was difficult to clarify it, further centrifugation was performed to obtain a residue of 7.4 kg and a separated fluid of 11.2 kg. Clarification, dehydration, drying and pulverization were carried out in the same manner as in Example 1 to obtain 201 g of powdered pectin. The yield of the product pectin based on the raw material peel was 13.4%, and the pectin concentration was the same as that of Example 2. The yield is significantly reduced as compared with Example 2.

Comparative Example 3 2 kg of a dried product of summer mandarin orange peel was washed with water and extracted in the same manner as in Example 1, and 200 g (insufficient amount) of a cellulose super-assisting agent was added to an extract solution of 1200 g of absolutely dry insoluble matter, followed by pressing. As a result, 2.1 kg of undissolved residue and 18.1 kg of juice were obtained. Since the squeezed juice contains a large amount of insoluble matter and is difficult to clarify, further centrifugation was performed to obtain a residue of 8.8 kg and a separated solution of 9.3 kg. Clarification, dehydration, drying and pulverization were carried out in the same manner as in Example 1 to obtain 165 g of powdered pectin. The yield of the product pectin based on the raw material peel was 8.3%, and the pectin concentration was determined in Example 3.
It is the same as that of. The yield is significantly reduced as compared with Example 3.

It is known from the above Examples and Comparative Examples that the addition effect of the pressing aid is clear, and it is known that the pectin concentration can be increased while maintaining good yield.

The device used for squeezing in these experiments is a screen press, P-special type, manufactured by Hans Fetter, and has a screen compression ratio of 1: 8.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References “Large Organic Chemistry Volume 20 Natural Polymer Compounds II” Asakura Shoten, Sho 40-10-30, 4th edition, p. 186-187 "Filtration device", Nikkan Kogyo Shimbun (sho 37.7.31) P. 8 and P.I. 16

Claims (1)

[Claims] 1. A squeezing aid is added to an extract obtained by extracting pectin from a pectin-containing plant or an insoluble matter separated from this extract in an amount of 30 to 20 per 100 parts by weight of the insoluble matter.
A method for producing pectin, which comprises adding 0 part by weight, squeezing to separate insoluble matter, and then clarifying and filtering the separated solution by a conventional method.