KR100885087B1 - A preparation method of gelatinized starch using extrusion process - Google Patents

Abstract

A method for preparing the gelatinized starch by using the extrusion molding method is provided to simplify the manufacturing process and to improve the uniformity of gelatinization. A method for preparing the gelatinized starch by using the extrusion molding method comprises the steps of extrusion molding the starch containing about 1-5 wt% of water with a screw rotation velocity of about 100-700 rpm in a first zone of 30-60°C, in a second zone of 60-90°C and in a third zone of 120-150°C of an extrusion molder; cutting the extrusion molded product; crying the cut one; and pulverizing the dried one.

Description

A preparation method of gelatinized starch using extrusion process}

The present invention relates to a method for producing gelatinized starch by the extrusion molding method, more specifically, by molding the starch in the beta state by changing the gelatinized (alpha) starch to produce starch with improved properties such as caking properties for industrial use It is to use.

Starch is a polysaccharide composed of glucose as a constituent unit. The properties of starch vary depending on the raw starch. The starch is made of modified starch or processed starch, which has undergone various treatments to change its original structure or physical properties. In pharmaceutical industry, it is widely used as a binder, thickener, gelling agent, stabilizer, binder, moisturizer, coating agent, molding agent and the like.

Gelatinization or gel hydration of starch is an increase in the water content of starch particles by heating, resulting in irreversible collapse of the starch particles after swelling, resulting in a transparent colloidal solution as the crystal structure of the starch particles collapses. . The viscosity increases, the X-rays change, and the conductivity increases. This may vary depending on the type of starch, heating method, stirring state, and the like.

Conventional methods for preparing luxury starch include hot cooking with heating as a heating operation, steaming with steam, and roasting of raw materials by direct or indirect methods, and swelling as swelling. (Batch Type Puffing) method, but the former has a long and cumbersome production process, such as heating after drying water or steam, the latter has a problem of change in appearance quality of the product and uniformity and commerciality of luxury .

Accordingly, an object of the present invention is to modify the starch into gelatinized starch by a simple production process through an extrusion molding method to use as an industrial caking agent.

In order to achieve this object, in the present invention, the starch is extruded under the conditions that the internal temperature of the extrusion machine is in the first zone 30 ~ 60 ℃, the second zone 60 ~ 90 ℃, and the third zone 120 ~ 150 ℃, After cutting the extrudate into chips, a method is provided for drying the cuts in the form of chips and grinding the dried products to produce gelatinized starch.

Starches that may be used in the present invention include, but are not limited to, rice, corn, wheat, potatoes and tapioca, but preferably tapioca starch is used. In particular, tapioca powders containing 5 to 13% by weight of water and having a particle size of 30 to 100 mesh are preferred. Tapioca is made by slicing the roots of cassava from the tropics and squeezing it to pulverize the remaining fiber after draining the juice. to be.

In the preparation of gelatinized starch according to the present invention, gelatinization is carried out using an extruder, and any extruder available in the present invention can be used, but the body is divided into three zones and Preferred twin-screw extruders are capable of varying the set temperature. At this time, the starch is gelatinized by the elevated temperature inside the extrusion machine divided into three zones. The degree of gelatinization required in the starch of the present invention is preferably 85% by weight or more, and the degree of gelatinization of starch is indicative of proportionality with cohesiveness. not. The production of starch with adequate degree of gelatinization is closely related to the temperature control inside the extruder. Inside the extrusion machine, the internal temperature of the first zone is 30-60 ° C. for heating the starch; The temperature of the second zone is 60-90 ° C. for gelatinization; It is preferable that the temperature of the third zone is maintained at 120-150 ° C. in order for the tapioca powder to be at high temperature and high pressure, and when the internal temperature of the three zones in the extruder falls within the above range, the degree of gelatinization is 85 It is possible to produce gelatinized starch of more than% by weight. The high temperature and high pressure gelatinized starch is extruded to the outside through the extrusion unit.

When the starch is administered to the raw material supply part of the extrusion molding machine in the extrusion step, the feed rate is preferably 3 kg to 11 kg / min, less than 3 kg / min there is a risk that the operation of the machine may not be smooth, 11 kg If it is more than / min there is a fear of overload. However, the feed rate of the raw material is correlated with the motor capacity of the extruder and can be changed in a wide range, it is not limited to the above range. The mixture is transferred into the extrusion molding machine by a screw, and the rotational speed of the screw is preferably about 100 to 700 rpm, but the rotational speed may be changed depending on the input amount of the raw material. It is not limited to the said range. In addition, the water supply for supplying water is preferably supplied to about 1 to 5% by weight based on the weight of the starch, which is a raw material, the supply amount of water may be changed according to the season and the processing state of the raw material, However, the present invention is not limited thereto, but it is preferable to set the water supply amount in the extrusion molding step so that the total moisture content in the starch is about 12% to 15% in consideration of the water content of the raw material in order to effect the gelatinization.

At this time, the extruded molding is used to cut the molding to a suitable size while controlling the rotation of the cutting unit by using a cutter, the cutter that can be used in the present invention includes any cutter available on the market, preferably a rotary blade cutter Can be used. The size of the molding to be cut is preferably in the form of a chip of 2 ~ 10mm. If the size of the chip is 2mm or less, it may be collected by the dust collector and the real error rate may be lowered.In order to induce the ease of workability when the chip is crushed in a later step, the size of the needle is preferably 10mm or less, which is also passed through the drying apparatus. The maximum size for easy moisture control.

The gelatinized starch in the form of cut chips is administered to a drying apparatus, and the drying apparatus available in the present invention may be any warm air drying apparatus available on the market. Through the high temperature hot air fan attached to the drying device to control the moisture that adversely affects the gelatinization state of the raw material. It is preferable to dry at a temperature of 50 ~ 80 ℃ temperature, wherein the water content is most preferably 10% by weight or less to maintain the gelatinization state. As shown in Table 2 below, when the internal temperature of the drying apparatus is 50 ° C. or less, the water content of the product becomes higher than 10% by weight. In such a case, the rate at which the gelatinized starch powder returns to the beta (β) state is accelerated, which adversely affects the cohesion of the product. You can slow down the pace enough. On the other hand, when the internal temperature of the drying apparatus is more than 80 ℃ it is possible to control the moisture content to 10% by weight or less, but the carbonization phenomenon of the starch occurs, the cohesiveness is deteriorated and unnecessary energy consumption is generated by supplying more heat source than necessary. In addition, the water content is particularly preferably 1 to 10% by weight, and when the water content is lowered to 1% by weight or less, prolongation of the drying time is generated, and economic efficiency is lowered. Deterioration of caking occurs due to the phenomenon.

When drying is complete, the dried chips are ground to prepare powder of gelatinized starch. Crushing of the chip may use any method known in the art, but preferably through a hammer grinder. The size of the powder is preferably in the range of 80 to 150 mesh. In order to exhibit the performance as an industrial caking agent, the gelatinized starch in a solid state should be in a liquid state within a short time. As shown in Table 3 below, when the particle size is in the range of 80 to 150 mesh, it takes time to liquefy. This is because the surface area per unit mass is large, allowing a greater amount of tapioca starch to react with water. When the tapioca gelatinized starch has a particle size of 80 mesh or less, the surface area per unit mass of gelatinized starch decreases, so that the amount of reaction with water decreases and the liquefaction time becomes longer. In addition, when 150 mesh or more, the performance as a binder is sufficiently exhibited, but when grinding a large amount of gelatinized starch is collected by the dust collector, the error rate is lowered, there is an inefficient side to supply more power than necessary.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

In the case of using the gelatinized starch production method of the present invention by the extrusion molding method, the production process is simpler than the cooking and steaming method, the quality of the product is easy to maintain and gelatinization can be made uniform. In addition, it has the properties of gelatinized starch that easily reacts with water to exhibit adhesiveness, making it easy to use as a caking additive.

<Example>

1. Starch Gelatinization Analysis by Extrusion Temperature

In the present embodiment, a twin-screw extruder was used to prepare gelatinized starch. The diameter of the extruder screw was 60 mm, the length and diameter ratio was 50: 3, and the injection hole was 5 mm in diameter. Used. Temperature control was controlled using a heater and cooling water. The raw material input was fixed at 3 kg / min at a screw rotation speed of 300 rpm.

30 kg of tapioca powder of 60 mesh containing 12% by weight of water was added to the twin-screw extruder, and 1% by weight of water was added to the raw material. At this time, while varying the temperature of the three zones inside the extrusion machine was analyzed the degree of gelatinization of the powder, Table 1 below shows the results. The inspection of the degree of luxury was used X-ray method.

[Table 1] Gelatinization degree of starch according to the internal temperature of each zone (moisture added 1% by weight of raw material)

division Temperature inside the first zone (℃) Temperature inside the second zone (℃) Internal Temperature of Zone 3 (℃) Luxury Example 1 30 60 120 ○ Example 2 30 80 120 ○ Example 3 30 90 120 ○ Example 4 30 60 140 ○ Example 5 30 60 150 ○ Example 6 30 80 140 ○ Example 7 30 80 150 ○ Example 8 30 90 150 ○ Example 9 50 60 120 ○ Example 10 50 60 150 ○ Example 11 50 80 120 ○ Example 12 50 80 150 ○ Example 13 50 90 120 ○ Example 14 50 90 150 ○ Example 15 60 60 120 ○ Example 16 60 80 120 ○ Example 17 60 90 120 ○ Example 18 60 60 150 ○ Example 19 60 80 150 ○ Example 20 60 90 150 ○ Comparative Example 1 20 80 140 X Comparative Example 2 20 50 140 X Comparative Example 3 20 80 100 X Comparative Example 4 20 50 100 X Comparative Example 5 20 100 100 X Comparative Example 6 20 100 140 X Comparative Example 7 70 80 140 X Comparative Example 8 70 80 100 X Comparative Example 9 70 100 100 X Comparative Example 10 70 50 100 X Comparative Example 11 70 50 140 X Comparative Example 12 70 100 150 X

                                                       (○: good, ×: poor)

As can be seen in [Table 1], the internal temperature of the three zones of the extrusion molding machine is in the temperature range of 30 ~ 60 ℃ in the first zone, 60 ~ 90 ℃ in the second zone, 120 ~ 150 ℃ in the third zone In this case, the degree of gelatinization of the tapioca powder is 85% by weight or more, which is the degree of luxury required by the present invention, but when one or more of the temperature ranges for the three zones are outside the range, the degree of gelatinization required by the present invention is 85% by weight. More than% was not satisfied.

2. Analysis of Tapioca Starch Moisture Content According to Drying Temperature after Extrusion

30 kg of tapioca powder of 60 mesh containing 12% by weight of water is added to the twin screw extrusion machine, 1% by weight of water is added to the raw material, and the temperature in the first zone is 50 ° C. and the temperature in the second zone is 50 ° C. It extrusion-molded at 70 degreeC and the internal temperature of 3rd zone to 135 degreeC. Thereafter, the blade was cut into chips having a size of 5 mm using a rotary blade cutting machine, and dried using a hot air drying device. The moisture content of the powder was analyzed while changing the temperature at the time of drying. Table 2 below shows the results.

[Table 2] Moisture Content of Tapioca Starch According to Drying Temperature after Extrusion

division Drying unit internal temperature (℃) Moisture content (% by weight) Remarks Example 1 50 7 ○ Example 2 70 5.5 ○ Example 3 80 5 ○ Comparative Example 1 40 12 X Comparative Example 2 30 15 X

                                                       (○: good, ×: poor)

As can be seen from Table 2 above, when the internal temperature of the drying apparatus is 50 ° C. or less, the water content of the product becomes higher than 10% by weight, so that the speed at which the tapioca powder is returned to beta is increased. On the other hand, when the internal temperature of the drying apparatus is more than 80 ° C., carbonization of starch may occur, resulting in deterioration of cohesiveness and unnecessary energy consumption due to supply of heat sources more than necessary.

3. Analysis of Liquefaction Time of Tapioca Starch According to Grain Size after Grinding

30 kg of tapioca powder of 60 mesh containing 12% by weight of water is charged into the twin screw extrusion machine, 1% by weight of water is added to the raw material, and the temperature inside the first zone is 50 ° C. and the temperature inside the second zone. Was extruded at 70 ° C. and the third zone internal temperature at 135 ° C. After that, using a rotary blade cutting machine was cut into chips of 5 mm size, dried using a hot air drying apparatus to less than 6% by weight of moisture at 60 ℃ and pulverized with a hammer grinder to prepare tapioca starch powder. The liquefaction time of the gelatinized starch was analyzed according to the particle size of the powder during the grinding, and the stirring speed during the liquefaction experiment was 20 rpm. Table 3 below shows the results. In the present invention, the maximum time required for the tapioca gelatinized starch to change into the liquid phase is set to 120 seconds. This is a time taken into consideration the mixing time of tapioca gelatinized starch and other substances.

 [Table 3] Liquefaction Time of Tapioca Gelatinized Starch According to Grain Size after Grinding

division Granularity (mesh) Liquefaction time (seconds) Remarks Example 1 80 110 ○ Example 2 110 95 ○ Example 3 150 80 ○ Comparative Example 1 70 140 X Comparative Example 2 50 210 X

                                                (○: good, ×: poor)

As confirmed from Table 3, the time taken for liquefaction was measured to be 120 seconds or less in the range of 80 to 150 mesh, and the particle size of tapioca gelatinized starch was 80 mesh or less as in Comparative Examples 1 to 2. In time, the time of liquefaction was measured to be 120 seconds or more.

Claims (6)

The internal temperature of the extruder is 30 ~ 60 ℃ in the first zone, 60 ~ 90 ℃ in the second zone, at a screw rotation speed of about 100 ~ 700 rpm. And extruding in the third zone at a temperature of 120 to 150 ° C. Cutting the extrudate; Drying the cut; And Pulverizing the dry matter Method for producing luxury starch comprising a. delete The method of claim 1, wherein the starch is selected from the group consisting of rice, corn, wheat, potato and tapioca starch. The method of claim 1, wherein the extrusion molded product is cut into chips of 2 to 10 mm in size. The method for producing gelatinized starch according to claim 1, wherein the cut material is dried under conditions of a temperature of 50 to 80 ° C so that moisture is 1 to 10% by weight. The method of claim 1, wherein the dried product is ground to 80 to 150 mesh.