JPS5910178B2 - Caramel refining method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for purifying edible caramel using a membrane separation method.

Edible caramel colorants are generally produced by adding a catalyst such as an acid, an alkali, or a salt to a sugar solution and then heating and roasting the mixture.

For example, when using sulfites (sodium salt, potassium salt, ammonium salt) as a catalyst, 10-35% sulfite is added to the raw sugar solution and the temperature is raised to 110-140℃.
However, since a large amount of sulfite is used in this case, there is a drawback that a large amount of sulfur dioxide gas remains in the product.

Methods for removing these residual sulfur dioxide gases include a method using an anion exchange resin, an oxidizing agent treatment method, and a pressure heating and pressure release treatment method, but the removal efficiency of sulfur dioxide gas has not yet been sufficient.

In order to improve this drawback, the present invention proposes a reverse osmosis membrane or an ultra-f
This method uses a membrane separation method to remove myelite from caramel.

According to the method of the present invention, for example, a molecular weight cutoff of 1000 to 5
000 ultrafiltration membrane can be used to efficiently remove sulfites in caramel, and at the same time remove organic acids such as low molecular weight glue puric acid, alcohol, esters, etc. as impurities contained in coloring substances. It can improve caramel quality.

Furthermore, according to the method of the present invention, the caramel coloring agent obtained from the same raw material can be separated into several hue groups having different hues by utilizing the amphoteric nature that is a feature of the membrane separation method.

That is, in general, the type of carbohydrate, pH adjustment, ammonia,
Products with different colors and properties can be produced depending on the addition of ammonium salts, amino acids, alkaline sodium compounds, heating conditions (temperature: time), etc., but in the present invention, products with different colors and properties can be made from the same raw material without changing the type of carbohydrate. I got something different.

For example, use a caramel colorant with a molecular weight cut-off of 40,000 or more (
Acrylonitrile copolymer ultrap membrane D manufactured by Daicel
UY-40), 20000 or more (DUY-20), 10
000 or more (DUY-10), 5000 or more (DUY-
05), 1,000 or more (cellulose acetate ultrafiltration membrane, DUC-01), and 500 or more (cellulose acetate reverse osmosis membrane, DBS-0) to obtain homogeneous composition from the same carbohydrate. It is classified into six groups with different hues ranging from dark brown to pale yellow, and can be used in various coloring agents from soy sauce to cola and lemon.

This will be explained below using examples.

Example 1 5 kg of purified glucose was dissolved in 1500 d of pure water,
720t of sodium sulfite was added and heated in an autoclave at 120°C for 3 hours to obtain liquid caramel 7220y.

This solution was diluted twice and diluted with an internal pressure tubular type ultrafiltration device manufactured by Daicel (tube diameter 14.5φ, length 75 crrL, membrane used: cellulose acetate ultrafiltration membrane DUC-0 1, pressure 7).
kg/cd, temperature 45° C., flow rate 2 m/sec, membrane area 0.277 j), ultrafiltration treatment was performed to reduce the volume reduction ratio to 1/2, and caramel having the properties shown in Table 1 was obtained.

For reference, the properties of the stock solution without reverse osmosis treatment were compared.

As shown in Table 1, according to this method, residual sulfite gas is
It was possible to obtain a high-quality purified caramel which had a concentration of 10 ppm or less, which was within the food tolerance range of 30 ppm, and which did not contain a small amount of impurities such as residual organic acid or alcohol.

Example 2 2 kg of starch syrup was dissolved in 6000 ml of pure water, and the pH was adjusted using a buffer solution containing a mixture of 1.4 mol potassium carbonate, 0.6 mol potassium bicarbonate, and 4N sodium hydroxide.
10 and heated and reacted at 125° C. for 60 minutes to produce caramel.

Using the same ultra-F filtration apparatus as in Example 1, the obtained caramel was first diluted to 2 times the stock solution and ultra-F filtrated to a volume reduction ratio of 1/2 using a DUY-40 membrane with a molecular weight cutoff of 40,000. Then, the permeation treatment liquid was subjected to ultrafiltration to a volume reduction ratio of 1/2 using a DUY-10 membrane with a molecular weight cutoff of iooooo, and the treated liquid was subjected to reverse osmosis using a reverse osmosis membrane DBS-0 with a molecular weight cutoff of 500. Processing was performed to obtain 4 kg of caramel liquid.

The properties of the obtained caramel were as shown in Table 2.

From the results in Table 2, membrane separation treatment of caramel does not significantly change the practical properties of caramel (it significantly changes the color tone and can be used for special purposes such as cola, soy sauce, meat, and lemon). was completed.

Claims (1)

[Scope of Claims] 1. A method for purifying caramel, which comprises using a reverse osmosis membrane or an ultrafiltration membrane to purify and remove impurities from a caramel colorant. 2. The purification method according to claim 1, which uses an ultraf membrane having a molecular weight cutoff of 1000 to 5000. 3. The purification method according to claim 1, wherein a reverse osmosis membrane or an ultrafiltration membrane having a molecular weight cutoff of 40,000 to 500 is used for fractionation in a stepwise manner from a membrane with a higher molecular weight cutoff to a membrane with a lower molecular weight cutoff.