JPS6246159B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a dextrin solution by liquefying starch by acting on a liquefying enzyme.

Glucose, maltose, invert sugar, etc. are industrially produced in large quantities by reacting enzymes such as saccharifying amylase β-amylase with a dextrin solution obtained by liquefying starch. To liquefy starch into dextrin, water is usually added to the starch.
This is done by making starch milk with a concentration of 30 to 45% and then treating it with starch liquefaction enzyme at high temperature, but at this time, when the concentration of starch milk exceeds 50%, the viscosity of starch milk suddenly decreases. It is not possible to increase the amount above 50% because this would make operations such as stirring and transportation difficult and cause physical problems. Therefore, the concentration of the dextrin solution obtained by liquefying starch milk and the saccharified solution obtained by saccharification of the dextrin solution is usually 35 to 40%.
is the limit. If high-concentration saccharified liquid could be produced without performing a concentration process such as evaporation, the cost required for concentration when producing glucose and maltose could be drastically reduced, which would have great economic merit. For production, a technology for producing a highly concentrated dextrin solution is required. Therefore, the present inventors conducted extensive research to develop a technology for producing high-concentration dextrin liquid, and as a result, 35-35~
40% starch milk is liquefied with a liquefying enzyme, then new starch is added to the dextrin solution to obtain 50-65% starch milk, which is then supplemented with a liquefying enzyme and liquefied again.
We were able to produce a high concentration dextrin solution of 50-65%. The method of the present invention will be explained below.

The starch liquefaction enzyme used in the present invention may be a normal liquefaction amylase, such as α-amylase derived from microorganisms such as Bacillus or Aspergillus.
Amylase is used; the liquefaction enzyme need not be specialized and commercially available products are readily available.

In the method of the present invention, water is first added to tapioca, sweet potato and potato starch to make 35-40% starch milk. The pH of starch milk is adjusted to 6.5-7.5 using an alkali. At this time, if necessary, add enzyme stabilizers such as NaCl, Ca, Mg, etc., and add the above liquefied amylase to 1 g of starch.
Add 20-50 units per batch and liquefy at 80-95°C for 30-60 minutes. After liquefaction, if necessary, let it cool and add new starch to make 50-65% starch milk. The physical properties of the starch milk thus obtained are similar to those of the initial starch, and it can be easily stirred and transported without any physical problems. A high concentration dextrin solution is obtained by liquefying this high concentration starch milk again at 80 to 95°C for 30 to 60 minutes. The method of the invention can be carried out not only batchwise but also continuously. To carry out the process continuously, a starch emulsification tank and a liquefaction tank are provided, and a part of the liquefied dextrin liquid is sent to the emulsification tank and circulated.

The high concentration dextrin solution obtained in this way is usually heated at 110 to 120°C for 10 to 20 minutes, and then treated with glucoamylase or β
-It is enzymatically saccharified by amylase etc. to become a 60-65% saccharified liquid. Glucose maldos can be obtained by purifying the saccharified liquid and concentrating and crystallizing it, but the method of the present invention is extremely economically advantageous because the cost required for concentration can be significantly reduced compared to conventional methods. It is.

Enzymatic saccharification liquid is used industrially in large quantities as a main raw material for various fermentations, and is usually continuously fed to a fermenter. In this case, the higher the concentration of the feed liquid, the more advantageous it is to fermentation production, so the saccharified liquid obtained by the method of the present invention is extremely desirable as a raw material for fermentation.

This will be explained in detail in Examples below.

Example 1 2.1Kg of tapioca starch (including 1.83Kg of starch) was added to water.
2.2, and the pH was adjusted to 7.0 using 1.3 g/dl caustic soda solution. 0.366 g of clystase (bacterial α-amylase agent manufactured by Daiwa Kasei Co., Ltd.) was dissolved in 100 ml of water, and this was added to the above suspension. While stirring the suspension, the liquid temperature was raised to 90°C, and liquefaction was performed while stirring at 90°C for 30 minutes. After liquefaction, let it cool down to a liquid temperature of 60
After cooling to ℃, add another 1.8Kg (1.14Kg of starch),
Adjusted pH to 7.0.

Add 0.8g of clystase to this and return to 90
Liquefaction was carried out for 30 minutes at °C. After completion of liquefaction, heat treatment was performed at 120°C for 10 minutes using a small autoclave, and the mixture was allowed to cool to obtain a high concentration (61%) dextrin liquid (DE.13.5).

Adjust the pH of this highly concentrated dextrin solution with 6N-sulfuric acid.
4.8 and add 2.26g of gluczyme (Amano Pharmaceutical Co., Ltd. sugar filamentous saccharifying amylase agent) to 100% of water.
72 ml at 55°C with gentle stirring.
Time saccharification was performed. The decomposition rate of the saccharified liquid was 98.5%, and the direct sugar concentration was 60.53%.

Claims (1)

[Claims] 1. A method for producing a dextrin solution by liquefying starch milk by applying a starch liquefaction enzyme, which is characterized in that starch is newly added to the starch liquefaction solution and a liquefaction enzyme is supplemented for liquefaction. Manufacturing method.