KR20150001057A - Preparation method of puffed rice powder extruded with enzyme for ready-to-eat foods - Google Patents

Abstract

The present invention relates to a method for manufacturing extrusion puffed rice flour by adding heat-resistant alpha-amylase to water to make an enzyme solution; injecting rice flour and the enzyme solution into an extrusion molding machine and performing an extrusion puffing process to make an enzymatically treated and extrusion puffed product; and grinding the enzymatically treated and extrusion puffed product. The extrusion puffed rice flour of the present invention has a low water adsorption index and thus reduces the content of the water used to manufacture dough or slurry including rice, thereby allowing the manufacture of dough or slurry having high solid contents. In addition, the extrusion puffed rice flour has a high water solubility index and a low starch polymerization degree and also has excellent dispersion stability, thereby being easily dispersed even in cold water. Furthermore, a dispersed solution of the extrusion puffed rice flour is maintained for a long period of time. Therefore, the extrusion puffed rice flour has excellent usability as a raw ingredient to manufacture an instant convenience food product such as instant porridge, baby food, beverage, etc. which can be taken instantly by only adding the water of room temperature to the extrusion puffed rice flour.

Description

Description: TECHNICAL FIELD The present invention relates to a preparation method of puffed rice powder extruded with an enzyme for ready-to-

The present invention relates to a process for producing extruded extrudate by simultaneously injecting a heat resistant alpha-amylase enzyme and a rice flour into a biaxial extrusion molding machine to produce an extruded extrudate and pulverize the extruded extrudate, To a method for producing a fine powder.

Rice is one of the most important energy sources of human cereals. In South and Southeast Asia, rice has been consumed for thousands of years in stocks and traditional foods. However, due to the influence of wheat imported from the 1950s, as the eating habits of Koreans due to wheat ingestion such as noodles, breads, confectionaries began to change, the rice consumption rate decreased every year and rice stocks increased, Research on development is urgently required. Therefore, studies using rice such as rice snack manufacturing, rice flour and other grains or raw materials, preparation of alpha derivatives, enzyme sensitivity studies, and extrudates made from rice have been actively conducted.

In recent years, research has been actively carried out to increase the consumption of rice through the expansion of rice products replacing conventional flour. There is also a plan to utilize rice for instant, simple transplantation (instant formula) considering nutrition, health and convenience. .

The instant, easy-to-take-side formula has features that can be cooked and cooked easily, which makes it difficult to cook, but it is beneficial for busy modern people to use it easily. Most of the quick-turn rounds are products derived from foreign diets. In overseas countries, wheat is used as a stock. Research on flour-based products is active, but products using rice are scarce. Most of them are dried by hot wind, It is a simple process that is already generalized, such as powdering.

Korean Patent Registration No. 10-0112127 discloses a method for producing instant porridge made by immersing grains in a hot water tank at 70 ± 20 ° C for lavaging and then lyophilizing to reduce the moisture to 2 to 5% Korean Patent Registration No. 10-0170801 discloses an instant pumpkin soup made by mixing old ingredients such as pumpkin powder, flour, etc. with a distributor (90-150 ° C) for 0.3 hour to mix the additives. Korean Patent Laid-Open Publication No. 10-1998-0065336 discloses a method for preparing instant rice cake food, which is prepared by hot-air drying at a moisture content of about 10 to 15% or freeze-drying at a moisture content of 5% or less, and then pulverizing it. 10-0034518 discloses a method for producing instant porridge, which comprises feeding rice flour, gravity powder, and salt as raw materials into a double compression molding machine, molding the mixture, and cutting and drying the mixture.

However, in the case of the pulverized product dried through the simple hot air drying or the steam boiling as described above, the cereals, especially the inside of the rice, are not evenly converted to the alpha, so that if sufficient heat is not applied by the flame burning, The flavor is lowered due to the change of color or the generation of odor due to drying. In the case of freeze-drying, it has the advantage of having a porous nature in molecular structure, so that moisture can penetrate quickly to the inside in a short time during cooking. However, since a preheating process for starch is needed separately, The productivity is lowered, and the manufacturing cost is excessively increased, which is not preferable.

In addition, if the product manufactured by the above-mentioned processing method requires additional cooking for 3 minutes or more by lighting, it is difficult to say that it is a genuine instant easy-to-eat type, and it is not enough to meet the demand of increasingly complicated consumers.

The extrusion process began to be applied to the industry as a solution to labor intensive technology in the 1930s, and was first applied to polymer plastic molding. The application to food began in the mid 1930s when it was used for pasta production. Recently, applied technology has been continuously developed in various industrial fields such as food, feed, bio-industry, and pharmaceutical industry [Critical Reviews in Food Science and Nutrition. 49, 361-368].

Various studies have been attempted to induce changes in the physicochemical properties of cereals by using extrusion cooking and enzyme treatment. Shin et al. Produced an extrudate by extrusion blending and then treated with an enzyme to induce an increase in water solubility index and soluble dietary fiber [Korean J. Food Sci. Technol. 35, 849-855] and Lee Kang Kwon et al. (1994) used three amylase enzymes (Termamyl 120LS, BAN 240L, malt powder) for the production of rice flour using a single screw extruder And thus obtained a low-viscosity swell which is desirable for the production of baby foods [Korean J. Food Sci. Technol. 26, 670-678]. These studies, however, have the disadvantage that they require time and manpower because they have a time-saving effect rather than a traditional manufacturing process but still have moisture content or enzyme processing steps separate from the extrusion cooking process.

Accordingly, it is possible to provide a quick-action, easy-to-use instant food which can be easily ingested by simply adding water at room temperature, exhibiting high water-solubility index and low starch polymerization degree, It is necessary to develop a transplant.

It is an object of the present invention to provide a food using rice which does not require heat treatment or emulsifying agent so that it easily dissolves and disperses in water without absorbing water and swelling up artificially within 1 to 2 minutes, The present invention is intended to provide an extruded expanded derivative having a low moisture adsorption index, a high water solubility index, a low starch polymerization degree, and a high digestibility, which can be utilized in the production of instant single piece transplantation.

In order to solve the above-described problems, the present invention provides a method for producing an enzyme solution, comprising: preparing an enzyme solution by adding 0.1-3 parts of heat-resistant alpha-amylase enzyme to 100 parts of water; Feeding the extruded material by simultaneously injecting the rice flour and the enzyme liquid into an extrusion molding machine; Extruding the extruded material at a barrel temperature of 70 to 105 DEG C and a screw rotation speed of 50 to 250 rpm to produce an extruded extrudate; And drying and pulverizing the extruded expanded material to prepare an extruded expanded fine powder.

According to an embodiment of the present invention, the extruded material may have a moisture content of 25-30% by weight, wherein an injection rate of the rice flour is 700-850 g / min and an injection rate of the enzyme liquid is 150-250 lt; RTI ID = 0.0 > mL / min. < / RTI >

According to another embodiment of the present invention, the thermostable alpha-amylase enzyme may be Termamyl 120L type L (Novozymes, Denmark, 120 KNU / g) derived from Bacillus licheniformis ,

The enzyme solution containing the heat-resistant alpha-amylase enzyme used in the extrusion may have a potency of 10-1000 KNU / kg.

The present invention also provides an extruded expanded derivative prepared by the above method.

Wherein the extruded expanded fine powder has a moisture content of 1 to 10% by weight, a moisture adsorption index of 0.5 to 2.5 g / g, a water solubility index of 20 to 40%, a starch polymerization degree of 3 to 7 glucose units, an alpha-amylase May be 73% or more, and the particle size may be 1-50 mesh.

In the present invention, the extruded expanded fine powder is characterized in that the dough, slurry or diluent containing rice is used in the manufacture of cotton products, breads, snacks, cereal, porridge, beverages or drinks used in the manufacturing process.

The extruded expanded fine powders prepared according to the method of the present invention were obtained by simultaneously injecting an enzyme solution containing rice flour and heat resistant alpha-amylase enzyme into a biaxial extrusion extruder, extruding under the conditions of a barrel temperature of 70-105 DEG C and a screw rotation speed of 50-250 rpm And the process time is shortened by unifying the process so that the process of adding enzyme and adjusting the moisture content is performed during the extrusion process. The extruded expanded fine powder according to the present invention has a lower moisture adsorption index than the pulverized rice flour which is extruded and expanded without processing the ordinary pulverized rice flour and the heat resistant alpha-amylase, so that the content of water used for preparing the dough or slurry containing rice is reduced, It is possible to produce a high dough or a slurry, has a high water-solubility index and a low starch polymerization degree, and is excellent in dispersion stability, so that it is easily dispersed in cold water and the dispersion is maintained for a long time. It is highly likely to be used as a raw material for the manufacture of ready-to-use transplantable products such as ready-to-eat porridge, baby foods, and drinks.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a graph showing the expansion rate of an extruded expanded product produced according to one embodiment of the present invention and a comparative example. FIG.
FIG. 2 is an image enlarged at 2000 times magnification by a scanning electron microscope in order to observe the microstructure of rice hulls and extruded swell produced according to an embodiment and a comparative example of the present invention. FIG. 2B is an image of the extruded bulb manufactured according to the comparative example, FIG. 2C is an image of the extruded bulb manufactured according to Embodiment 2 of the present invention, FIG. An image of the extruded bulb made according to Example 4.
3 is a graph showing the average degree of polymerization of extruded expanded fine powders prepared according to one embodiment of the present invention and a comparative example.
4 is a graph showing the starch digestibility of the extruded expanded fine powder prepared according to one embodiment of the present invention and a comparative example.
5 is a graph showing a water absorption index (WAI) and a water soluble index (WSI) of extruded expanded fine powders prepared according to one embodiment of the present invention and a comparative example.
FIG. 6 is a graph showing the paste-enhanced viscosity of the extruded expanded fine powder prepared according to one embodiment of the present invention and a comparative example.
7 is a graph showing dispersion stability of extruded expanded fine powders prepared according to one embodiment of the present invention and a comparative example.

The extrusion molding process is a processing method in which raw materials are mixed, crushed, molded and dried by a high temperature and short time (HTST) process in a single process. The sample is mixed by a rotating screw while pushing the sample in the barrel, and shearing and heat treatment are simultaneously performed by the shear and heat treatment so that the properties of the material are deformed to the molecular bonding level. Therefore, the cutting, crushing, In addition to structural changes such as amorphous starch particles, low molecular weight through dextrinization, protein denaturation, intermolecular binding and organization, microorganisms are killed and sterilized, toxic substances are destroyed, odors are removed, density is controlled, It is an economical and efficient process compared with other heat treatment process because it proceeds quickly in a single process.

Extrusion process conditions can be controlled by feed rate, screw rotation speed, barrel temperature, moisture content, structure of outlet and screw arrangement. By controlling these independent variables, nutrient bioavailability can be improved as well as improving digestibility. Such as pasta, vegetable protein, dry beverage mix, dried soup, cereal, baby food, porridge, snacks, fish meat and meat processing.

Accordingly, the present inventors have made intensive efforts to solve the above problems by using an extrusion molding process, and as a result, they have found that a twin screw extruder according to the present invention can be used for extrusion processing simultaneously with heat resistant alpha-amylase enzyme Amylase enzyme at a temperature of 70-105 ° C, which is the optimum temperature for the enzyme activity. Thus, it has a high water-solubility index and low starch polymerization degree, and is excellent in dispersion stability and suitable for the production of instant, The present invention has been completed by developing a method for producing an extruded expanded powder.

According to the present invention, the heat-resistant α-amylase enzyme randomly hydrolyzes α-1, 4-glucoside bonds of starch to produce various oligosaccharides having a relatively high molecular weight along with dextrin having a low molecular weight These effects lead to changes in properties such as viscosity reduction of starch, increase in reducing power, change in Iodine-color reaction, change in optical rotation force, decrease in turbidity of glycogen solution. In the present invention, Termamyl 120L type L (Novozymes, Denmark, 120 KNU / g) derived from Bacillus licheniformis, which is known as a heat-resistant enzyme exhibiting optimal activity at a temperature of 90-100 ° C., was used.

According to the present invention, the extrusion blowing process using the twin screw extruder in the same direction not only shortens the process time, but also proceeds with the addition of water at the same time as the water addition process so that the moisture content adjustment process is performed during the extrusion process This is a unification process with time and manpower reduction effects.

According to the present invention, the extrusion blowing process using a twin screw extruder in the same direction can induce a high pressure and a layer pushing phenomenon as compared with the uniaxial extrusion molding, thereby accelerating the molecular change of the rice,

The extruded extrudate can be prepared at a temperature of 70-105 ° C, which is lower than the conventional temperature, and the heat-resistant amylase enzyme can be used during the extrusion process, thereby shortening the process time and improving the time and economy.

Hereinafter, the present invention will be described in detail.

In the present invention, the term " instant, single-handed transplantation " means a food which can be easily cooked in a short time, is simple to store and preserve, is easy to transport and easy to carry, Does not require special heat treatment or emulsifier, can use room temperature water, and can use refrigerated water.

In the present invention, the rice flour is obtained by pulverizing rice. The size of the rice flour is not limited, but it is preferably 1-50 mesh. When the size of the rice flour is less than the above range, the surface area increases, The particles tend to be entangled with each other to cause a caking phenomenon, and if the particle size exceeds the above range, the particles are too large to exhibit a rough texture.

The present invention relates to a process for preparing an enzyme solution by adding 0.1-3 parts of heat-resistant alpha-amylase enzyme to 100 parts of water of skin; Feeding the extruded material by simultaneously injecting the rice flour and the enzyme liquid into an extrusion molding machine; Extruding the extruded material at a barrel temperature of 70 to 105 DEG C and a screw rotation speed of 50 to 250 rpm to produce an extruded extrudate; And drying and pulverizing the extruded expanded material to prepare an extruded expanded fine powder.

The extruded material may have a moisture content of 25-30% by weight. The feed rate of the rice flour in the extruded material is 700-850 g / min, and the rate of injecting the enzyme is 150-250 ml / min. Lt; RTI ID = 0.0 >

Preferably, the thermostable α-amylase enzyme is Termamyl 120L type L (Novozymes, Denmark, 120 KNU / g) derived from Bacillus licheniformis. The optimum temperature for the enzyme activity of Termamyl 120L type L is 90-100 ° C. Suitable for the present invention to produce extrudates at barrel temperatures of 70-105 ° C.

According to the present invention, the heat-resistant alpha-amylase enzyme can be used in an amount of 0.1 to 3 parts per 100 parts of water, more preferably 0.4 to 3 parts of the skin. Even when used in excess of the above range, the degree of increase in the effects of reduction in expansion ratio, decrease in starch polymerization degree, increase in starch digestibility, decrease in moisture absorption index, increase in water solubility index, decrease in paste viscosity viscosity and increase in dispersion stability is insufficient, If the amount is less than the above range, the amount of the enzyme is too small and it is difficult to expect the effect of the heat resistance-alpha amylase addition.

According to the present invention, the enzyme solution containing the heat-resistant alpha-amylase enzyme used in the extrusion molding may have a potency of 10-1000 KNU / kg,

For example, the enzyme solution of the present invention may have a potency of 110-130 KNU / kg when 100 parts of water and 0.4 part of heat-resistant alpha-amylase enzyme are used in skin, 0.8 part of heat-resistant alpha-amylase enzyme, When used, it may have a titer of 230-250 KNU / kg, and when using 3 parts of skin, it may have a titer of 920-940 KNU / kg.

According to the present invention, when extrusion molding is carried out beyond the temperature and the rotational speed range, there is a problem that the degree of rehydration deteriorates because the gelation does not occur completely, which is not preferable.

According to the present invention, the extruded expanded fine powder produced by the above production method has a powder content of 1 to 10% by weight, a moisture adsorption index of 0.5 to 2.5 g / g, a water solubility index of 20 to 40% To 7 glucose units, and the digestibility by the heat-resistant alpha-amylase may be 73% or more,

The extruded expanded fine powder may have a particle size of 1-50 mesh.

When the size of the particles is out of the above range, pulverization may cause a problem of poor yield and water solubility, which is not preferable.

According to the present invention, the extruded expanded fine powder can be used for producing a cotton product, bread, snack, cereal, baby food, porridge, beverage or drink in which a dough, a slurry or a diluent containing rice is used in the manufacturing process, It is more useful for making high calorimetric products with fluidity such as ready-to-eat porridge, baby foods and beverages that require a water solubility index.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. It will be apparent, however, to those skilled in the art that these embodiments are for further explanation of the present invention and that the scope of the present invention is not limited thereby.

Preparation of materials

The rice flour was prepared by pulverizing rice with a pulverizer (Future Food Industrial Machinery, Seoul, Korea) and passing it through a 50 mesh sieve, and storing it in a desiccator.

The heat-resistant alpha-amylase enzyme is a thermostable alpha-amylase Thermamyl 120L (Novozymes, Denmark; activity of 120 KNU / g (6,000 BAU / g)) isolated from Bacillus licheniformis at an optimal activation temperature of 90-100 ° C. Were used. The enzyme has an optimum pH of 5.5 to 7.0, an optimum temperature of 90 to 95 ° C, and a heat-resistant enzyme having the property that enzyme activity is not inactivated up to 5 minutes at 100 ° C.

Example

Extruded expanded powders were produced by pulverizing extruded extrudates according to enzyme concentration in a single process by adding heat - resistant α - amylase enzyme during extrusion molding process using rice flour as a raw material.

Example 1.

The extruded material was extruded using a twin screw extruder (Model DZ56-III, Jinan Saixin Machinery Co., Ltd., China). The screw diameter of the extruder was 65 mm, (L / D ratio) of 15.5: 1 in the diameter-to-length ratio, 75 rpm in the screw rotation speed, 780 g / min in the sample injection speed, and 1 bar, 2 bar and 3 barrel temperature of the extruder 85, and 95 < 0 > C, respectively.

For enzymatic treatment of the rice flour, 40 ml of heat resistant alpha-amylase per 10 liters of water was added to prepare an enzyme solution of 0.04 vol%.

Rice flour was injected at 0.775 Kg / min so that the moisture content of the extruded material was 30% by weight, and the enzyme solution was injected at 200 mL / min and extrusion molded to produce an extrudate. The enzyme had a potency of 123.84 KNU / Kg.

The resulting extrudate was dried in a dryer at 70 ° C for 15 hours, pulverized by a pulverizer and sieved with a 50 mesh sieve to prepare an extruded expanded fine powder.

Example 2.

Except that 0.08% by volume of the enzyme solution was used instead of the enzyme solution of 0.04% by volume. The activity of the enzyme extruded powder was 247.68 KNU / Kg.

Example 3.

Extruded expanded powder was prepared by the method of Example 1 except that an enzyme solution of 3 vol% instead of the enzyme solution of 0.04 vol% was used, and the enzyme had a potency of 928.8 KNU / Kg.

Example 4.

The extruded expanded fine powder was prepared by the method of Example 1 except that 5 vol.% Of the enzyme solution was used instead of 0.04 vol.% Of the enzyme solution. The enzyme had a potency of 1548 KNU / Kg.

Comparative Example 1

Extruded expanded fine powder was prepared by the method of Example 1, except that enzyme-free water was used instead of the enzyme solution of 0.04% by volume.

Comparative Example 2

Instead of heat-resistant alpha-amylase Aspergillus oryzae The extruded expanded fine powder was prepared in the same manner as in Example 1, except that the resulting alpha-amylase was used.

Comparative Example 3

Aspergillus instead of heat-resistant alpha-amylase oryzae The extruded expanded fine powder was prepared in the same manner as in Example 3, except that the resulting alpha-amylase was used.

Comparative Example 4

Extruded expanded fine powders were prepared in the same manner as in Example 1, except that the barrel temperatures of the first, second and third zones of the biaxial co-extrusion extruder were adjusted to 55, 60 and 65 ° C, respectively.

Comparative Example 5

Extruded expanded fine powders were prepared in the same manner as in Example 1 except that the barrel temperatures of the first, second and third zones of the biaxial co-extrusion extruder were adjusted to 110, 115 and 120 ° C, respectively.

Comparative Example 6

Extruded expanded fine powder was prepared in the same manner as in Example 1, except that the screw rotating speed of the biaxial co-axial extrusion molding machine was adjusted to 300 rpm instead of 75 rpm.

Test Example

The degree of starch digestibility, expansion ratio, microstructure, water adsorption index, water solubility index, paste viscosity, and dispersion stability of the extruded expanded product prepared according to the examples were measured.

Test Example  1. Measurement of average polymerization degree

The average degree of polymerization was calculated by dividing total sugar by the number of reducing ends in the sample. The sample for the experiment was prepared by adding 1 g of extruded bulk powder to a centrifuge tube, adding 50 mL of distilled water, reacting at 200 rpm for 1 hour at 50 ° C, centrifuging (1800 rpm, 20 minutes) 11 μm filter (Whatman, grade 1, Buckinghamshire HP7 9NA, England) and used as a test solution for measuring the total sugar and reducing end number. The total amount of sugar was determined by phenol-sulfuric acid method [Anal. chem. 28,350-356]. Add 1 mL of 5% phenol solution to 1 mL of sample solution, mix thoroughly, add 5 mL of concentrated sulfuric acid, and mix thoroughly to allow hydrolysis to proceed. After incubation at room temperature for 30 minutes, absorbance was measured at 470 nm. For the standard solution, D-glucose was prepared at 25 ~ 100 ug / mL, reacted by the same method, and a calibration curve was prepared and the sugar content was calculated by comparing with the test solution. The reducing end number was modified by the Park-Johnson method [Carbohydrate Research. 94, 205-213]. Sodium carbonate-sodium hydrogencarbonate buffer (potassium cyanide, 4.8 g Na ₂ CO ₃ , 9.2 g NaHCO ₃ , 0.65 g KCN) containing 0.5 mL potassium ferricyanide (1 g / L) Dissolved in distilled water), boiled for 15 minutes, and then cooled in water flowing for 10 minutes. 2.5 mL ferric ammonium sulfate (3 g / L of 50 mM H ₂ SO ₄ ) was added to the cooled test tube and the absorbance was measured at 715 nm after exactly 20 minutes. For the blank sample, distilled water was used instead of the test solution. The standard solution was prepared by diluting the 5 ug / mL solution of D-glucose in the same manner as the sample, and then using a calibration curve to calculate the reducing end number of the test solution.

Enzyme concentration (vol%) Average polymerization degree Standard Deviation Example 1 0.4 5.93 ± 0.25 Example 2 0.8 4.97 ± 0.14 Example 3 3 4.42 ± 0.15 Example 4 5 3.85 ± 0.06 Comparative Example 1 0 62.76 ± 0.51 Comparative Example 2 0.4 59.15 ± 0.35 Comparative Example 3 3 58.48 ± 0.27 Comparative Example 4 0.4 39.40 ± 0.42 Comparative Example 5 0.4 47.24 ± 0.51 Comparative Example 6 0.4 40.84 ± 0.26

As shown in Table 1, Comparative Example 1 in which the enzyme was not added showed 62.76 ± 0.51, whereas the extruded expanded fine powder with the enzyme showed a DP range of 3.85 to 5.93 depending on the enzyme addition ratio. This is the case with the Korean J. Food Sci. Technol. 28, 1996 44-52] reported that the average degree of polymerization of amylose and amylopectin was 597-878 and that of 2660-3140 glucose units was significantly lower than that of the amylose and amylopectin, indicating that the starch structure was destroyed under the temperature and pressure conditions above the gelatinization temperature of the extrusion- And the DP was reduced to about 3.8 ~ 5.9 by the enzyme treated in the extrusion process.

Also, Aspergillus oryzae Comparative Examples 2 and 3, which were extruded and expanded by adding the resulting alpha-amylase, showed no significant difference from Comparative Example 1 in which no enzyme was added. This means that Aspergillus oryzae It is presumed that the resultant alpha-amylase enzyme could not withstand the temperature during the extrusion process and lost enzyme activity.

Comparative Example 4 in which the barrel temperatures of Zone 1, Zone 2 and Zone 3 of the biaxial extrusion co-extruder were adjusted to 55, 60 and 65 ° C, respectively, showed that the average degree of polymerization was lower than that of Comparative Example 1 due to the enzyme, And DP was about 39.40. In Comparative Example 5 where the barrel temperature was high, the enzyme activity was lowered due to the high temperature, and the DP was about 47.

On the other hand, in Comparative Example 6 in which the screw speed is 300 rpm, it is presumed that the starch chain can not be cut sufficiently due to the extreme expandability due to insufficient pressure due to the high speed.

As a result, it was found that the starch chain of the extrudate was severely broken as the amount of the heat resistant α-amylase was increased and the optimum temperature of the heat-resistant α-amylase was in the range of 70-105 ° C. As the addition ratio of enzyme increased, the degree of polymerization tended to decrease significantly, but the difference was small.

Test Example  2. Measurement of expansion rate

The diameter of the cross-sectional area of the extruded expanded material prepared in Examples 1 to 4 was measured with a caliper (VC-15, Mitutoyo Co., Tokyo, Japan) and the expansion ratio was calculated by dividing by the ratio of extruder outlet diameter. Fifty samples of the dried extrudate (sample) were taken and the expansion ratio was calculated. The average and standard deviation were shown in Table 2 and FIG. 2, respectively.

Enzyme concentration (vol%) Expansion ratio Standard Deviation Example 1 0.4 1.47 ± 0.08 Example 2 0.8 1.24 ± 0.05 Example 3 3 0.88 ± 0.05 Example 4 5 0.90 ± 0.07 Comparative Example 1 0 2.18 ± 0.08 Comparative Example 4 0.4 1.86 ± 0.12 Comparative Example 5 0.4 2.09 ± 0.05 Comparative Example 6 0.4 1.74 ± 0.14

The expansion ratio of the extruded expanded material without addition of the enzyme solution was 2.18 ± 0.08, which was found to expand more than twice the diameter of the injection port. On the other hand, the expansion rate of the enzyme-treated extrudate was significantly decreased with an increase in the amount of the enzyme solution. Example 1 was expanded to about 1.5 times the diameter of the injection, and Example 2 was expanded to about 1.2 times the diameter of the injection. In Examples 3 and 4, it can be confirmed that the diameter of the extrudate is smaller than the diameter of the discharge port, so that the extrudate is hardly expanded. It is considered that the diameter of the extruded expanded material is smaller than the diameter of the extruded material during the drying process after extrusion. It is believed that this is due to cleavage of the starch chain structure resulting in an average degree of polymerization.

On the other hand, the extruding expansion rate expanded at a low barrel temperature and a high barrel temperature was reduced by the enzymatic treatment to a smaller diameter of the extrudate than that of Comparative Example 1, 1, respectively. Also, in Comparative Example 6 in which the screw rotation speed was fast, the extrusion expanded material was expected to be larger in diameter than that of Example 1 due to insufficient drying during the drying process, and the expansion was not sufficiently performed due to insufficient pressure.

Test Example  3. Measurement of microstructure

Extruded extrudates prepared according to Examples 2 and 4 and Comparative Example 1 were dried at 70 ° C for 15 hours and then subjected to field emission scanning electron microscopy (JSM-7100F, Jeol Ltd., Akishima-shi, Japan) Microstructure was measured and microstructure of rice grain was measured and compared as a control to check the grain structure of starch. A platinum coating was applied for 150 seconds on a gold foil coater (Sputter coater 108 auto, Cresington Co., Watford WD19 4BX, England), and the dried sample was observed at 15 kV.

The grain structure of the starch was confirmed in FIG. 3A in which the grain of the rice grain was enlarged. However, as shown in FIG. 3B, in the case of the extruded expanded material, it was melted and agglomerated so that the grain shape could not be confirmed. As can be seen from FIGS. 3b to 3d, the surface of the extrudate was more susceptible to the formation of intermittently formed large spaces due to the erosion of the amorphous as the enzyme concentration was higher, and the granule form of the raw starch was not seen.

Test Example  4. Determination of starch digestibility

1 g of extruded bulk powder (sample) was dispersed in 30 mL of phosphate buffer (0.2 M, pH 6.9), and the dispersion test tube was gelled in a constant temperature water bath at 95 ° C for 30 minutes and cooled to room temperature at 25 ° C. After incubation at 37 ° C for 1 h, the cells were incubated at 37 ° C for 1 h at room temperature. The resulting solution was diluted to 0.12 mg / mL with 3100 units of α-amylase (Sigma, A6380, Saint Louis, USA) ) At 100 rpm for 16 hours. The enzyme reaction was terminated by adding 5 mL of 1.0% sulfuric acid solution to the reaction tube and centrifuged at 3,000 rpm (Combi-514R, Hanmil Science Industrial Co., Inchon, Korea). The centrifuged sediment was washed twice with 80% ethanol, dried at 105 ° C for 2 hours, and the weight of the dried precipitate was measured. The starch digestibility was calculated as follows by comparing with the weight of the extruded extruded powder.

In this formula,

Sample dry weight = Weight of dried flesh powder. 1g.

Sediment dry weight: After the starch digestibility reaction, the sediment obtained by centrifugation was dried at 105 ° C for 2 hours.

The changes in starch digestibility according to the heat-resistant alpha-amylase enzyme concentration added during extrusion molding are shown in Table 3 and FIG.

Enzyme concentration (vol%) Starch digestibility Standard Deviation Example 1 0.4 75.25 + - 3.88 Example 2 0.8 76.03 ± 2.38 Example 3 3 85.50 ± 2.01 Example 4 5 85.42 ± 1.28 Comparative Example 1 0 64.64 ± 1.52

The starch digestibility of the extruded expanded fine powder according to Comparative Example 1 was 64.64 ± 1.52%, and it was confirmed that the extruded expanded material significantly increased by the injection of the enzyme solution. Extruded puffiness showed the lowest digestibility when dried. In case of this experiment, the extruded extrudate without added enzyme showed similar results because it was dried at 70 ℃ for 15 hours. The digestibility increased as the α-amylase addition rate increased. The results for Examples 1 to 4 were 75.25 ± 3.88, 76.03 ± 2.38, 85.50 ± 2.01, and 85.42 ± 1.28, respectively. The digestibility was significantly different according to the presence or absence of α-amylase. The starch digestibility increased as the enzyme addition ratio increased, suggesting that starch low molecular weight resulted from the average degree of polymerization. Examples 1 and 2 show no significant difference from each other, and Examples 3 and 4 are also the same.

Test Example  5. Measurement of Moisture Adsorption Index and Moisture Solubility Index

1 g of extruded bulk powder (sample) was added to a 50 mL centrifuge tube and dispersed with 10 mL of distilled water. The mixture was shaken at 100 rpm for 30 minutes in a constant temperature water bath at 30 ° C., and centrifuged (2500 rpm, 20 minutes) . The supernatant was transferred to an aluminum plate and dried in a hot air drier at 105 ° C for 2 hours. After cooling for 30 minutes in a desiccator, the weight was measured and the water absorption index (WAI) and water dissolution index soluble index, hereinafter referred to as WSI) was measured and shown in Table 4 and FIG.

The moisture adsorption index is expressed as the amount of water absorbed per gram of the dry sample by weighing the precipitate except for the supernatant. The calculation formula of the water solubility index and the water adsorption index is as follows.

In this formula,

Mass of hydrated sample = weight of precipitate after supernatant after centrifugation

Mass of sample = weight of extruded expanded powder

Solid content of supernatant = mass after centrifugation, supernatant transferred to aluminum plate, dried at 105 ° C for 2 hours, allowed to stand for 30 minutes in a desiccator, and then measured for solid content.

Enzyme concentration (vol%) Moisture absorption index (%) Water Solubility Index (%) Example 1 0.4 25.64 + 1.02d 2.12 + 0.06b Example 2 0.8 29.61 + - 2.31c 1.89 ± 0.13 c Example 3 3 36.22 + 1.45a 1.29 ± 0.05 d Example 4 5 33.48 + - 0.56b 1.11 ± 0.04e Comparative Example 1 0 5.06 ± 0.39e 4.06 ± 0.01a

The water solubility index of Example 1 was increased about 5 times and the water adsorption index was reduced to 1/2 compared to Comparative Example 1. [ As shown in Table 4, as the amount of? -Amylase added increases, the water solubility index increases, while the moisture adsorption index tends to decrease.

When the α-amylase was added, the starch low molecular weight was further increased to increase the water solubility index and the amylopectin was further decreased and the moisture adsorption index decreased. In addition, the water solubility index increased sharply up to about 5 times by the addition of α-amylase, which is presumably due to the increase of water-soluble substances by the action of amylase.

In the case of low degree of polymerization, it was confirmed that the water solubility index increases with decreasing moisture adsorption index when the starch chain cleavage is increased, and it is expected that the water solubility index will be more useful for the development of single use liquid product as the water solubility index increases.

Test Example  6. Measurement of the viscosity of the paste

3 g of the extruded expanded fine powder according to Example 1-4 and Comparative Example 1 was placed in an aluminum can for viscosity measurement, and 25 mL of distilled water was added thereto, followed by heating to a gelatinization temperature. The viscosity of the resulting paste was measured with a rapid visco analyzer (RVA-Techmaster, Perten Inc., Hagersten, Sweden) and the viscosity of the paste was measured using rice flour as a control. The temperature condition for gelatinization was maintained at 50 캜 for one minute at an initial temperature of 50 캜, then heated to 95 캜 for 3 minutes and 48 seconds, maintained at 95 캜 for 2 minutes and 30 seconds, and cooled to 50 캜 for 3 minutes and 48 seconds Then, the temperature was maintained for 1 minute and 24 seconds. The total time required was 12 minutes and 30 seconds. To increase the dispersion of the sample, the pedal was rotated at 960 rpm for 10 seconds and then the viscosity was measured at 160 rpm. The viscosity curve of the extruded expanded paste was obtained three times in total and the peak viscosity, PV, TV, final viscosity, breakdown viscosity , BV) and setback viscosity (SV) were calculated and expressed as mean and standard deviation values, respectively. The results are shown in Table 5 below.

Peak Lowest point Dielectric breakdown viscosity Final viscosity Countercurrent viscosity Peak time Passing temperature Control group 2026.0 ± 46.2 ^a 1138.7 ± 49.7 ^a 887.3 ± 15.5 ^a 2365.7 ± 56.9 ^a 339.7 ± 11.7 ^a 6.0 ± 0.0 ^a 88.9 ± 0.5 Example 1 27.0 ± 2.7 ^c 13.7 ± 1.5 ^c 13.3 + - 4.26 ^c 22.3 + - 0.6 ^c -4.7 ± 3.1 ^c 2.4 ± 0.1 ^e - Example 2 26.7 ± 3.2 ^c 9.7 ± 1.2 ^c 17.0 ± 2.7 ^c 15.7 ± 1.2 ^c -11.0 + - 2.7 ^c 4.3 ± 0.0 ^c - Example 3 15.0 ± 2.0 ^c 5.0 ± 1.0 ^c 10.0 ± 1.0 ^c 7.7 ± 0.6 ^c -7.3 ± 1.5 ^c 3.2 ± 0.1 ^d - Example 4 16.0 ± 1.0 ^c 4.0 ± 1.7 ^c 12.0 ± 1.0 ^c 7.7 ± 1.5 ^c -8.3 ± 2.1 ^c 3.3 ± 0.2 ^d - Comparative Example 1 703.3 ± 7.1 ^b 326.3 + 5.0 ^b 377.0 ± 2.7 ^b 740.0 ± 2.7 ^b 36.7 ± 8.4 ^b 5.3 ± 0.0 ^b 95.2 ± 0.1

The paste viscosity is generally used to measure the macromolecular degradation of the extruded starch, and the degree of starch decomposition and viscosity change of the extruded swollen material can be observed. As a result of measuring the viscosity of the control rice flour, the peak viscosity (PV) was 2026 cP, and the viscosity of the extruded rice flour without addition of the enzyme solution of Comparative Example 1 was measured to be about 703 cP. The PV of the extruded swollen material was compared with the rice flour It was confirmed that the amount of the water was reduced by about 1/3. The trough viscosity (TV) showed about 1138 cP of rice flour, and the rice swelling extrudate without enzyme solution showed 326, and the lowest point was also decreased about 1/4. The breakdown viscosity (BV), which indicates the degree to which the starch particles are easily collapsed when the starch suspension is cooled from 95 ° C to 50 ° C, is 887 cP for the rice flour and 337 cP for the rice flour extrudate without the enzyme solution / 2. The setback viscosity (SV), which indicates the final viscosity (FV) and the degree of increase in viscosity after cooling (degree of aging), is also significantly lower than that of rice flour And the peak time (PT) decreased from 6.0 to 5.3, but the pasting temperature increased from 88.9 to 95.2 ℃. As a whole, it was confirmed that the viscosity of the extruded extruded rice flour without addition of the enzyme solution was lower than that of the rice flour, indicating that the viscosity was decreased due to the low molecular weight caused by the extrusion process.

In the case of the extruded expandable material of Comparative Example 1 and the extruded expanded material of Example 1, the extruded expandable material of Example 1 was reduced by 1/26 to 1/33, and the SV and the PT were remarkably decreased in PV, TV, BV and FV . The reason why the pasting temperature is not measured is that the extruded swell is completely lengthened by the treatment of the enzyme, and it is no longer considered to be luxurious.

In the case of enzyme - treated extruded blended samples, the viscosity according to the added enzyme concentration was not significantly different in PV, TV, BV, FV and SV, but showed a slight but significant decrease in PT. It is considered that this is mainly due to low molecular weight due to hydrolysis of starch by enzymatic treatment, and when the extrusion process is performed, the starch chain structure is severed and the viscosity is greatly decreased, and the enzyme treated extrudate undergoes strong enzyme reaction It seems to be totally luxurious.

Test Example  7. Measurement of dispersion stability

30 test tubes were prepared and each of the extruded expanded powders prepared according to Examples 1 to 4 and Comparative Example 1 was filled with 25 mL of distilled water and the extruded expanded powders prepared in Examples 1 to 4 and Comparative Example 1 were dispersed at 2, 3, 4, 5, 6, and 7 g , 16, 20, 24, 28% by weight) was added to the test tube and dispersed using a voltex mixer to make a suspension. The 15 mL-test tube was filled to a height of 12 cm. The height of the precipitate after 1, 12, and 24 hours from the beginning of the initial dispersion was measured, and the stability of the dispersion solution was calculated as a percentage of the suspension height as shown in the following Table 6 and FIG.

Dispersion concentration (% by weight) Extrusion blowing
differential Enzyme concentration
(volume%) Dispersion stability (%) After 1 hour After 12 hours After 24 hours

8

Control group 0 10.8 4.2 5.0 Example 1 0.4 5.0 4.2 5.0 Example 2 0.8 4.2 4.2 5.8 Example 3 3 4.2 4.2 4.2 Example 4 5 95.8 62.5 55.8 Comparative Example 1 0 62.5 58.3 58.3

12

Control group 0 20.8 20.8 21.7 Example 1 0.4 8.3 4.2 5.8 Example 2 0.8 5.8 5.8 6.7 Example 3 3 4.2 4.2 5.8 Example 4 5 91.7 67.5 61.7 Comparative Example 1 0 87.5 81.7 82.5

16

Control group 0 47.5 33.3 28.3 Example 1 0.4 100.0 100.0 100.0 Example 2 0.8 100.0 100.0 99.2 Example 3 3 99.2 87.5 84.2 Example 4 5 89.2 78.3 70.0 Comparative Example 1 0 100.0 100.0 100.0

20

Control group 0 33.3 37.5 37.5 Example 1 0.4 100.0 100.0 100.0 Example 2 0.8 100.0 100.0 99.2 Example 3 3 99.2 90.8 86.7 Example 4 5 91.7 80.8 75.8 Comparative Example 1 0 100.0 100.0 100.0

24

Control group 0 41.7 45.8 45.8 Example 1 0.4 100.0 100.0 100.0 Example 2 0.8 100.0 100.0 99.2 Example 3 3 98.3 87.5 85.8 Example 4 5 89.2 80.0 69.2 Comparative Example 1 0 100.0 100.0 100.0

28

Control group 0 95.8 45.8 49.2 Example 1 0.4 100.0 100.0 100.0 Example 2 0.8 100.0 100.0 99.2 Example 3 3 100.0 99.2 95.0 Example 4 5 95.8 80.0 76.7 Comparative Example 1 0 100.0 100.0 100.0

In the case of the dispersion concentration of 8 wt% and 12 wt%, the extruded expanded fine powder of Comparative Example 1 and the extruded expanded fine powder of Example 4 were not dispersed in distilled water and the precipitate was separated in a short time.

On the other hand, in the case of the dispersion concentration of 16 to 24 wt%, the extruded expanded fine powder of Comparative Example 1 rapidly absorbed water at room temperature and swelled to exhibit a viscous gel shape, and did not separate from the water layer after 24 hours . These results are consistent with the results of WAI at the 0% enzyme addition. It can be used as a food and beverage that can be instantly rinsed even at room temperature if it is easily released from cold water and the dispersion liquid is maintained for a long time.

Except for the extruded expanded fine particles of Comparative Example 1 in which the gel was hardened, the extruded expanded differentialsamples showing the most stable dispersion stability were the extruded expanded derivatives of Examples 1 and 2 which contained 0.4 vol% of the enzyme and 0.8 vol% of the enzyme. The extruded expanded fine powders of Examples 3 and 4 were separated into supernatant and precipitate over time, and the extruded expanded powders of Examples 1 and 2 did not sink even after 24 hours. In Examples 3 and 4, the WSI is very high but the WAI is very low, and it is presumed that the extruded expanded fine powder absorbs moisture and can not be dispersed and layer separation occurs.

Extruded Expanded fine powder is well dispersed and well swollen. It absorbs and disperses water in 1-2 minutes. It can easily dissolve and disperse in water even if it is not artificially resolved. It is possible to use special heat treatment or emulsifier at room temperature. And it can be utilized as food and beverage with high calorie density that can be eaten instantly.

Claims (7)

100 parts of water Heat-resistant alpha-amylase enzyme 0.1-3 part for skin Preparation of an enzyme solution by adding skin;
Feeding the extruded material by simultaneously injecting the rice flour and the enzyme liquid into an extrusion molding machine;
Extruding the extruded material at a barrel temperature of 70 to 105 DEG C and a screw rotation speed of 50 to 250 rpm to produce an extruded extrudate; And
And drying and pulverizing the extruded expanded material to produce extruded expanded fine powder. The method according to claim 1, wherein the extruded material has a moisture content of 25-30% by weight. The method of claim 1, wherein the feeding rate of the rice flour is 700-850 g / min and the feeding rate of the enzyme is 150-250 mL / min. The method according to claim 1, wherein the heat-resistant alpha-amylase enzyme is Termamyl 120L type L (Novozymes, Denmark, 120 KNU / g) derived from Bacillus licheniformis . 5. A process for producing starch according to any one of claims 1 to 4, wherein the water content is 1 to 10% by weight, the water absorption index is 0.5 to 2.5 g / g, the water solubility index is 20 to 40% Is 3 to 7 glucose units, and the starch digestibility by the heat-resistant alpha-amylase is 73% or more. 6. The extruded expanded differential according to claim 5, wherein the extruded expanded fine powder has a particle size of 1-50 mesh. The extruded expanded fine powder according to claim 5, wherein the extruded expanded fine powder is used for producing a cotton product, a bread, a snack, a cereal, a baby food, a porridge, a beverage or a drink in which a dough, a slurry or a diluent containing rice is used in the manufacturing process Extruded expanded differential.

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