JPH01171451A - Production of 'konjak' - Google Patents

Abstract

PURPOSE:To continuously obtain a 'konjak' (devil's-tongue) of uniform hardness in a simple manner, by charging a twin-screw extruder with a water-swollen product from glucomannan, mixing with an alkali while agitating followed by extrusion. CONSTITUTION:A water-swollen product from glucomannan is fed into a twin- screw extruder, being mixed with an alkali while agitating for 3-120sec followed by extrusion to obtain the objective 'konjak'. Said glucomannan to be used includes glucomannan itself, 'konjak' powder and raw material containing glucomannan in high concentration. This raw material may be incorporated with a small amount of natural-occurring coloring matter, seasoning, spice, animal or vegetable oil, phytoprotein, lecithin, vitamine(s). Said twin-screw extruder to be used may be of any type, provided that mutually engaging two screws are equipped in the barrel.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing konjac, particularly to a method for continuously obtaining konjac of uniform hardness in an extremely simple method.

Conventionally, konjac is made by adding water to glucomannan and
After holding for 40 minutes and heating and swelling if necessary, a few percent of alkaline solution is mixed uniformly, held in a molding container for 3 to 4 hours, and then heated and coagulated and dealkalized in hot water in sequence. It was a product.

Therefore, the operation is complicated, requires a great deal of labor and time, and is inefficient.

On the other hand, as a method to overcome these drawbacks, it is known to prepare konjac paste by adding an alkali to a hydrolyzed swollen product of glucomannan, insert this into a screw type extruder, and mold it to obtain konjac. There is.

However, this method has the disadvantage that the konjac obtained at the initial stage is soft due to the short reaction time with the alkali, whereas the konnyaku obtained at the final stage is hard and brittle. That is, it has the disadvantage that it is not possible to obtain konnyaku with a constant hardness.

Therefore, the present inventors conducted intensive research to develop a new method for producing konnyaku that does not have these drawbacks, and as a result, they inserted the hydrolyzed glucomannan swollen product into a twin-screw extruder and mixed it with alkali. After mixing and stirring for 3 to 120 seconds, it was found that konnyaku with constant hardness could be obtained very easily and always with constant hardness, and based on this knowledge, the present invention was completed.

That is, the present invention is a method for producing konjac, which is characterized in that a hydrolyzed swollen product of glucomannan is inserted into a twin-screw extruder, mixed with an alkali, mixed and stirred for 3 to 120 seconds, and then extruded.

The present invention will be explained in detail below.

First, the glucomannan used in the present invention refers to a raw material containing a high concentration of glucomannan, such as glucomannan or konjac flour.

Furthermore, small amounts of natural pigments, seasonings, spices, animal and vegetable oils, vegetable proteins, lecithin, vitamins, etc. may be added to this raw material, if necessary.

Next, as the twin-screw extruder, any type of extruder may be used as long as it has two mutually meshing screws in a barrel, such as a twin-screw extruder.

Next, in order to carry out the present invention, water is added to glucomannan so that the water content becomes 92 to 99.5%, and the glucomannan is held for 3 to 40 minutes to form a swollen product.

This swollen product is inserted into a twin-screw extruder and mixed with an alkali in the barrel.

Examples of the alkali used here include known alkali compounds such as calcium hydroxide, sodium hydroxide, and sodium carbonate.

The amount of alkali added to the swollen product is determined by the amount of alkali added to the swollen product.
The amount is such that H is 9 to 13, preferably 1) to 12.5. For example, 5 to 1 per 100 parts by weight of the swollen product.
Add 6-2% by weight of 5% calcium hydroxide solution.

As described above, when an alkali is mixed with the swollen product in the barrel, gelation rapidly progresses and becomes irreversible, resulting in konjac when extruded from the discharge port of the barrel.

Mixing and stirring time of the swollen product and alkali in the barrel is 3 to 1
20 seconds, preferably 5 to 30 seconds.

If the time is less than 3 seconds, the alkali will not be mixed uniformly,
In addition, elastic konnyaku cannot be obtained; on the other hand, if the time is longer than 120 seconds, an irreversible gel will form in the barrel, and as a result of being mixed and stirred again, a brittle or shapeless konnyaku will result.

Hereinafter, the effects of the present invention will be specifically explained with reference to experimental examples.

Experimental Example A sheet-shaped konnyaku product was manufactured in the same manner except that the mixture of the swollen product and alkali was mixed and stirred in the barrel as shown in Table 1, and the effect of the mixing and stirring time on the product was investigated. Ta.

The results are shown in Table 1.

Next, by appropriately changing the shape of the die during the extrusion, molded products in the form of sheets, rods, threads, etc. can be obtained.

Next, the extruded konjac is kept in hot water or hot water for a sufficient period of time to achieve the desired hardness, and after being heated and coagulated, it is sufficiently dealkalized in flowing water. Product.

Hereinafter, the present invention will be specifically illustrated with reference to Examples.

Example 1 3 kg of glucomannan and 97 g of water were mixed and held for 30 minutes to obtain a swollen product.

Here, 100 yen from the input port of the twin-screw extruder.
Insert the extruder at a supply rate of 0 kg/hr, and add 10% calcium hydroxide solution to the barrel of the extruder.
kg/hr, and without heating from the outside of the barrel, after mixing and stirring for 15 seconds, it was continuously extruded into a sheet from a discharge port (die) and cut into a rectangular shape.

Next, this was held in boiling water for 10 minutes to heat and coagulate, then exposed to running water at room temperature for 12 hours and drained to obtain a sheet-like konjac.

There was no difference in the hardness of this konnyaku between the early extrusion stage and the late extrusion stage.

Patent applicant Kikkoman Corporation

Claims (1)

[Claims] (1) A method for producing konjac, which comprises inserting a hydrolysed glucomannan product into a twin-screw extruder, mixing it with an alkali, mixing and stirring for 3 to 120 seconds, and then extruding it.