CN113598355A

CN113598355A - Modified konjak slurry and preparation method and application thereof

Info

Publication number: CN113598355A
Application number: CN202110920535.0A
Authority: CN
Inventors: 武妍丽; 何永德; 吕芬; 薛万永
Original assignee: Guangyuan Jiudaoliang Food Co ltd
Current assignee: Guangyuan Jiudaoliang Food Co ltd
Priority date: 2021-08-11
Filing date: 2021-08-11
Publication date: 2021-11-05

Abstract

The invention relates to the technical field of food, and particularly discloses modified konjak slurry and a preparation method and application thereof. The modified konjak slurry is prepared from the following raw materials in parts by weight: 55-78 parts of konjac fine powder, 0.6-3.3 parts of wheat protein, 0.1-0.6 part of amino acid, 0.3-1.5 parts of edible gum and water; the preparation method comprises the following steps: s1, respectively pre-dissolving the wheat protein, the edible gum and the amino acid; s2, dissolving the konjac powder in water, heating and stirring; s3, adding the wheat protein liquid and the edible gelatin solution, heating and stirring; and S4, adding an amino acid solution, heating and uniformly stirring to obtain the modified konjak slurry. The modified konjak pulp prepared by the method can be applied to preparing konjak foods such as konjak pieces, konjak tofu, konjak shreds, konjak noodles, konjak bionic products and the like, so that the konjak foods are more powerful and have high elasticity.

Description

Modified konjak slurry and preparation method and application thereof

Technical Field

The invention relates to the technical field of food, in particular to modified konjak pulp and a preparation method and application thereof.

Background

The konjac powder is a hydrophilic colloid, and can fully absorb water and swell when being added into a proper amount of water, so that a high-viscosity dispersion system or gel is formed. The konjak powder is classified according to the granularity, and the konjak fine powder is more than 90% of granules with the granularity of 0.125-0.425 mm. The refined rhizoma Amorphophalli powder is rich in Konjac Glucomannan (KGM), a heteropolysaccharide formed by random distribution of D-mannose and D-glucose at a ratio of 1:6 and linkage of beta-1, 4 glycosidic bonds. The C6 position of every 9-19 mannose residues on the KGM molecular main chain has 1 acetyl substitution, and the structural characteristic has very important application significance on the dissolubility and the gelatibility of the KGM molecular main chain. KGM has the characteristics of high viscosity, good biocompatibility, easy degradation and the like, and has excellent bioactivity, so that KGM is widely used in the fields of food, medicine, nutrition and the like.

The gelling characteristics of the konjac fine powder are divided into two types: thermally irreversible gelation and thermally reversible gelation. For example, when konjac fine powder is used for preparing konjac tofu, heat irreversible gelation occurs. In the process, KGM molecules in the konjac powder are deacetylated by adding alkali and heating, molecular chains are intertwined into a three-dimensional network structure, and a stable heat irreversible gel is formed.

At present, when konjak foods (such as konjak tofu, konjak vegetarian tripe, etc.) are prepared by utilizing the heat irreversible gelation property of konjak fine flour, it is common to prepare a semi-finished product by adding water to the konjak fine flour to prepare a slurry (stirring during the slurry preparation), adding alkali to perform aging, and then obtaining the konjak foods such as konjak tofu by dicing, slicing, molding, etc. The refined powder of konjak is classified into a special-grade refined powder of konjak, a first-grade refined powder of konjak, a second-grade refined powder of konjak, a third-grade refined powder of konjak, and a fourth-grade refined powder of konjak according to its sensory, particle size, and physicochemical indices (e.g., viscosity, moisture, ash content, and glucomannan content). Wherein the second-grade refined konjac flour, the third-grade refined konjac flour and the fourth-grade refined konjac flour are low-grade refined konjac flour. When the second-level konjac fine powder, the third-level konjac fine powder and/or the fourth-level konjac fine powder are selected and used for preparing konjac tofu and other products in the market, a stable gel state is difficult to form under the conventional preparation process, so that in the preparation process, after a proper amount of starch is added to the konjac fine powder, the konjac tofu and other foods are prepared, and a better gelling effect is obtained. However, the konjak foods prepared by this method are not chewy enough and have a poor chewing feeling.

Disclosure of Invention

In order to better utilize low-grade konjac refined powder and enable konjac foods prepared from the low-grade konjac refined powder to be more chewy and elastic, the invention provides modified konjac paste and a preparation method and application thereof.

In a first aspect, the invention provides a modified konjak slurry, which adopts the following technical scheme:

the modified konjak slurry is prepared from the following raw materials in parts by weight:

55-78 parts of konjac fine powder, 0.6-3.3 parts of wheat protein, 0.1-0.6 part of amino acid, 0.3-1.5 parts of edible gum and water; the edible gum is selected from one or more of locust bean gum, guar gum, xanthan gum and acacia gum.

The main effective substance in the konjac powder is KGM, and a large amount of hydroxyl contained on the molecular chain of KGM enables the konjac powder to have excellent water binding capacity, and can be combined with water which is 200 times of the own weight; moreover, KGM also contains a certain amount of acetyl groups. Under the condition of heating and adding alkali, acetyl of the konjac fine powder is removed, so that the water solubility of KGM molecular chains is reduced, and the formation of gel is further promoted. The wheat protein is rich in the gliadin and glutenin; the interaction between the gliadin and glutenin forms a net structure, so that foods (steamed bread, noodles and the like) prepared from the wheat flour are more chewy and have elasticity.

By adopting the technical scheme, the konjac refined powder and the wheat protein are mixed, and the konjac refined powder is modified in a slightly alkaline environment by adding the wheat protein to form modified konjac paste, so that the konjac food prepared from the konjac paste has better elasticity and chewing taste. In the process, only wheat protein is added, so that the chewy mouthfeel of the finally prepared konjak food is improved, but is not obvious. A small amount of edible gum and amino acid are added at proper time, so that the prepared konjak food has obviously improved chewy mouthfeel and stronger chewing feeling. Wherein, the edible glue and the konjac powder are main substances formed by the gel, the edible glue and the konjac powder are interacted to form a more stable net structure, and the wheat protein enters the net structure through intermolecular force, Van der Waals force and the like and is stably connected; the addition of amino acids further enhances the stability of the connection of the wheat protein and the colloidal network structure. Finally, the konjak food prepared by the modified konjak slurry is more chewy, has high elasticity and better chewing feeling.

Preferably, the konjac powder is one or a mixture of two-stage konjac powder, three-stage konjac powder and four-stage konjac powder.

The invention mainly aims at the problem that the konjak food has insufficient elasticity when the low-grade konjak flavor powder (namely the second-grade konjak flavor powder, the third-grade konjak flavor powder and the fourth-grade konjak flavor powder) is used for preparing the konjak food.

Preferably, the konjak slurry is prepared from the following raw materials in parts by weight:

62-71 parts of konjac fine powder, 1.2-2.2 parts of wheat protein, 0.3-0.5 part of amino acid, 0.6-1.1 part of edible gum and water.

By adopting the technical scheme, the using amount of the raw materials is further optimized, so that the modified konjac refined powder is further optimized, and the elasticity and chewing mouthfeel of the konjac food prepared from the modified konjac pulp are further improved.

Preferably, the edible gum is locust bean gum and acacia gum.

By adopting the technical scheme, the locust bean gum and the Arabic gum are added together and are used as main substances for forming gel together with the konjac refined powder, and the gel system is compounded with the wheat protein and the amino acid to obtain modified konjac paste; when the obtained modified konjak slurry is used for preparing konjak foods, the obtained konjak foods have better elasticity (2.72-3.24 mm) and chewiness (5010.59-6505.30 g).

Preferably, the weight ratio of the locust bean gum to the Arabic gum is (1.2-2.6): 1.

By adopting the technical scheme, the modified konjac syrup with more excellent performance is obtained by further optimizing the adding proportion of the locust bean gum and the Arabic gum.

Preferably, the weight ratio of the konjac powder to the water is 1 (15-20).

Preferably, the amino acid is one or both of L-lysine and L-arginine.

By adopting the technical scheme, the L-lysine and/or the L-arginine are/is selected to better react with hydroxyl on KGM molecular chains of the konjac powder, so that the connection stability between the wheat protein and the konjac powder is further enhanced, the konjac powder can be effectively modified, and the konjac food prepared from the modified konjac slurry is more chewy and has high elasticity.

In a second aspect, the invention provides a preparation method of the modified konjac syrup, which adopts the following technical scheme:

a preparation method of the modified konjak slurry comprises the following steps:

s1, pre-dissolving a proportion of wheat protein into an alkali liquor to obtain a wheat protein solution, pre-dissolving a proportion of edible gum into an edible gum solution, and pre-dissolving a proportion of amino acid into an amino acid solution;

s2, dissolving a certain amount of konjac powder in water, wherein the weight ratio of the konjac powder to the water is 1 (15-20), and then heating and stirring at 45-50 ℃ for 0.5-1 h to obtain basic konjac slurry;

s3, mixing the wheat protein liquid and the edible gelatin solution, adding the mixture into the basic konjac syrup, and heating and stirring for 0.5-1 h to obtain optimized konjac syrup;

and S4, adding an amino acid solution into the optimized konjak slurry, heating and stirring to be uniform thick slurry to obtain the modified konjak slurry.

By adopting the technical scheme, when preparing the modified konjak slurry, the basic konjak slurry is prepared, and after heating and stirring for a period of time, the wheat protein and the edible gum (namely the wheat protein liquid and the edible gum solution) are added in a solution form. Wherein, the wheat protein liquid is firstly mixed into the edible gelatin solution and then mixed into the basic konjak slurry, because the edible gelatin solution and the konjak slurry have similar properties and are easy to mix, the wheat protein liquid and the edible gelatin solution are simultaneously added, which is beneficial to the full mixing of the whole material system. After the wheat protein enters the gel formed by the konjac refined powder and the edible gum, the wheat protein and hydroxyl groups on KGM and other related groups act to realize the modification of the konjac refined powder. The addition of the edible gum promotes the mixing of the wheat protein on one hand and further stabilizes the interaction between the wheat protein and the konjac powder on the other hand. And then, amino acid is added to further enhance the stability of a system formed by the wheat protein, the konjac powder and the edible gum, so that the quality of the modified konjac paste is effectively improved, and the prepared konjac food is more elastic.

Preferably, the stirring speed in S3 is 800-1000 rpm.

By adopting the technical scheme, in the state, the obtained gel is in a more viscous gel state, and the amino acid is fully mixed with the optimized konjac paste by high-speed stirring; further, the function of the amino acid is exerted more fully, thereby being more beneficial to improving the quality of the modified konjak slurry and ensuring that the konjak food prepared from the modified konjak slurry is chewy and elastic.

Preferably, the preparation method of the wheat protein liquid comprises the following steps: adding alkali to adjust the pH value of the water to 7.5-8, mixing the wheat protein and the water according to the weight ratio of (1-8) to 100, and uniformly stirring.

By adopting the technical scheme, the wheat protein is dispersed in the solution in advance, so that the wheat protein is better dispersed in the basic konjak slurry, the interaction between the wheat protein and the konjak flavor powder is facilitated, and the modified konjak slurry with excellent performance is finally obtained.

Preferably, the preparation method of the amino acid solution comprises the following steps: adding alkali to adjust the pH value of the water to 7.5-8.5, mixing the amino acid and the water according to the weight ratio of (5-12) to 100, and uniformly stirring.

By adopting the technical scheme, the amino acid is dissolved in the solution in advance, so that the amino acid plays a role in optimizing the konjak pulp, and finally the modified konjak pulp with excellent performance is obtained.

In a third aspect, the invention provides an application of the modified konjac syrup, which adopts the following technical scheme:

the modified konjak pulp can be used for preparing konjak foods such as konjak pieces, konjak tofu, konjak shreds, konjak noodles, konjak bionic products and the like.

In conclusion, the invention has the following beneficial effects:

1. the invention mixes water, konjak refined powder, wheat protein, amino acid and edible gum in a specific proportion to prepare modified konjak pulp with excellent performance; the konjak food prepared from the modified konjak slurry has the advantages of higher elasticity, chewiness and chewy strength.

2. The selection of the edible gum is further optimized, the locust bean gum and the Arabic gum in the weight ratio of (1.2-2.6): 1 are used as the edible gum, the quality of the modified konjak slurry is further improved, and the elasticity of the konjak tofu prepared from the modified konjak slurry is up to 2.81-3.24 mm.

3. According to the invention, when the modified konjac paste is prepared, after the amino acid is added, the stirring speed is controlled within the range of 800-1000 rpm, the stability of the system cannot be damaged due to high-speed stirring on the premise of fully mixing the amino acid and other components in the optimized konjac paste, and the finally obtained modified konjac paste is rich in elasticity and better in taste when the konjac food is prepared from the modified konjac paste.

Detailed Description

The present invention will be described in further detail with reference to examples.

The raw materials involved in the invention are all food grade raw materials which are commonly obtained on the market unless otherwise specified. The rhizoma Amorphophalli refined powder is purchased from second-grade rhizoma Amorphophalli refined powder, which can be purchased from Henan Yu Domain biotechnology limited, and has performance index meeting the related requirements of NY/T494 (rhizoma Amorphophalli powder) on second-grade rhizoma Amorphophalli refined powder. The wheat protein is also called wheat gluten and gluten flour, and can be purchased from the Jinan union such as chemical engineering and technology Limited company, and is food grade, with the product model of RG-1 and the product model of LR 02. The locust bean gum can be obtained from Hebei Tuohai Biotech limited, CAS9000-40-2, with a product content of 99 wt%; xanthan gum is available from Sinkian magnificence Biotech Inc., food grade, CAS 11138-66-2; the guar gum can be purchased from Henan Su lotus Biotech limited, food grade, with a guar gum content of 99.9 wt%; acacia gum is available from Shandong Anbaili Biotech, Inc., food grade, cat # 005. In order to facilitate stirring and mixing, the wheat protein, the locust bean gum, the guar gum, the xanthan gum and the Arabic gum are all powdery raw materials.

Examples

Example 1

The modified konjak pulp comprises 550g of konjak fine powder, 6g of wheat protein, 1g of amino acid and 3g of edible gum, wherein the edible gum is locust bean gum, and the amino acid is L-lysine.

The preparation process of the modified konjak slurry comprises the following steps:

s1, adjusting the pH value of water to 8 by using 30 wt% NaOH solution, then suspending and dispersing the wheat protein in 150g of water according to the proportion, and adding alkali liquor to promote the dispersion of the wheat protein to obtain the wheat protein liquid. The locust bean gum with the proportion amount is dispersed and dissolved in 30g of water to obtain the locust bean gum liquid. The pH of the water was adjusted to 8.2 with 30 wt% NaOH solution, then the proportional amount of L-lysine was dissolved in 10g of water, and the addition of lye to promote the dissolution of L-lysine resulted in the L-lysine solution.

S2, dissolving a proportional amount of konjac powder in 9.9kg of water, and then stirring for 1h at a constant temperature of 48 ℃ and 400rpm to obtain basic konjac paste;

s3, uniformly mixing all the wheat protein liquid and all the locust bean gum liquid, adding the mixture into the basic konjak slurry, and stirring at the constant temperature of 50 ℃ and 300rpm for 1h to obtain optimized konjak slurry;

s4, adding an L-lysine solution into the optimized konjac paste, and stirring for 0.5h at a constant temperature of 50 ℃ and 900rpm to obtain the modified konjac paste.

In the following examples and comparative examples, the weight ratio of wheat protein to water when dispersing wheat protein is 4: 100, respectively; when dissolving L-lysine, the weight ratio of L-lysine to water is 10: 100; when dissolving locust bean gum, the weight ratio of locust bean gum to water is 10: 100.

Examples 2 to 7

Examples 2 to 7 are different from example 1 in the ratio of raw materials for preparing the modified konjak slurry, and are shown in table 1, and the others are the same as example 1.

TABLE 1

Example 8

This example differs from example 6 in the selection of the edible gum; in the embodiment, the locust bean gum in the embodiment 6 is replaced by the guar gum with the same weight, and the formula and the proportion of other raw materials are the same as those in the embodiment 6.

This example differs from example 6 in the preparation of a modified konjac syrup in that: when dissolving guar gum in S1, 100g of water is used to dissolve the dispersed guar gum, and the guar gum solution is obtained. The other steps are the same as in example 6. In the following examples and comparative examples, the weight ratio of guar gum to water when dissolving guar gum is 10:100, unless otherwise specified.

Example 9

This example differs from example 6 in the selection of the edible gum; in this example, 6g of xanthan gum and 4g of guar gum (the total weight of edible gum is 10g) are used to replace 10g of locust bean gum in example 6, and the formula ratio of other raw materials is the same as that in example 6.

This example differs from example 6 in the preparation of a modified konjac syrup in that: in S1, when dissolving xanthan gum and guar gum, 1.5g of glucose, 6g of xanthan gum and 4g of guar gum are mixed, and then added to 100g of water, so that the xanthan gum and guar gum are dispersed in the solution, thereby obtaining an edible gum solution. The other steps are the same as in example 6.

Example 10

This example differs from example 6 in the selection of the edible gum; in this example, the locust bean gum of example 6 was replaced by equal weight of gum arabic, and the other formulation was the same as that of example 6.

This example differs from example 6 in the preparation of a modified konjac syrup in that: in S1, when gum arabic is dissolved, gum arabic is dissolved and dispersed in 100g of water, and the mixture is stirred until the gum arabic is sufficiently dissolved to obtain gum arabic liquid. The other steps are the same as in example 6.

Example 11

This example differs from example 6 in the selection of the edible gum; this example was conducted in the same manner as example 6 except that 10g of locust bean gum in example 6 was replaced with 6g of locust bean gum and 4g of gum arabic (total weight of edible gum: 10 g).

This example differs from example 6 in the preparation of a modified konjac syrup in that: and S1, when the locust bean gum and the Arabic gum are dissolved, adding the locust bean gum and the Arabic gum in the formula amount into 100g of water, and uniformly stirring (when the edible gum is dissolved, ensuring that 10g of the edible gum is dissolved and dispersed by 100g of water), so as to obtain the edible gum liquid. The other steps are the same as in example 6.

Examples 12 to 15

This example differs from example 11 in the weight ratio of locust bean gum to gum arabic, which is shown in table 2, and is otherwise the same as example 11.

TABLE 2

Detailed description of the preferred embodiments	Locust bean gum/g	Arabic gum/g	The weight ratio of locust bean gum to acacia gum
				Example 11	6	4	1.5:1
Example 12	4.5	5.5	0.8:1
				Example 13	5.6	4.4	1.2:1
Example 14	7.2	2.8	2.6:1
				Example 15	7.5	2.5	3.0:1

Comparative example 1

The comparative example differs from example 11 in that the raw material for producing the modified konjac syrup was not added with an amino acid (i.e., neither L-lysine nor L-arginine was added), and the weight of the wheat protein was 22g, and the other examples were the same as example 11.

Namely, in the comparative example, the formula proportion of the modified konjak paste is as follows: 650g of konjac fine powder, 22g of wheat protein, 6g of locust bean gum and 4g of arabic gum.

When dissolving wheat protein, 22g of wheat protein is dissolved in 550g of water, the pH value of the solution is adjusted to 8 by using 30 wt% of NaOH solution, and the wheat protein solution is obtained after uniform mixing.

Comparative example 2

The comparative example is different from example 11 in that no edible gum is added to the raw material for preparing the modified konjac syrup, and the weight of the wheat protein is 28g, and the other example is the same as example 11.

Namely, in the comparative example, the formula proportion of the modified konjak paste is as follows: 650g of konjak fine powder, 28g of wheat protein and 4g of L-lysine.

When dissolving wheat protein, adjusting pH of water to 8 with 30 wt% NaOH solution, dissolving 28g of wheat protein in 700g of water, and stirring to obtain wheat protein solution.

Comparative example 3

The present comparative example is different from example 11 in that wheat protein was not added to the raw material for preparing the modified konjac syrup in the present comparative example, and the total weight of the edible gum was 28g (of which, locust bean gum 16.8g and gum arabic 11.2g), and the other example was the same as example 11.

Namely, in the comparative example, the formula proportion of the modified konjak paste is as follows: 650g of konjac fine powder, 16.8g of locust bean gum, 11.2g of Arabic gum and 4g of L-lysine.

The modified konjak pulp prepared by the invention can be used for preparing konjak foods, such as konjak tofu, konjak broad bean flour, konjak strings, konjak tripe and the like.

Comparative example 4

The comparative example preparation of konjac syrup comprises the following steps:

s1, dissolving 950g of secondary konjac powder in 11L of water, and then stirring for 1h at a constant temperature of 48 ℃ and 400rpm to obtain an initial mixed solution;

s2, stirring at 50 deg.C and 300rpm for 1.5h to obtain rhizoma Amorphophalli slurry.

The same general commercial second-grade konjac powder as in example 1 was used for this comparative example.

Application example

The modified konjak slurry is used for preparing konjak tofu, and the specific preparation steps are as follows:

I. dissolving 2g of soda ash into 18g of water to obtain soda ash solution;

II. Taking 300g of the prepared modified konjak slurry, adding all prepared pure alkali liquor, boiling until the mixture is formed, and cooling to obtain konjak blocks;

III, cutting the konjak blocks into 3cm × 1.5cm × 1cm size to obtain konjak tofu.

The modified konjak pulps of examples 1 to 15 were numbered 1 to 15, respectively, and the konjak pulps prepared in comparative examples 1 to 4 were numbered 16 to 19, respectively. The konjak pulps numbered 1 to 19 were used for preparing konjak tofu, and the konjak tofu numbered 1 to 19 were obtained, respectively.

The konjak tofu of nos. 1 to 19 thus prepared were subjected to texture property detection and sensory evaluation, respectively.

First, texture detection

The texture characteristics of the konjak tofu were analyzed by a texture analyzer (TPA). The test parameters are: and (3) testing the probe P/35, wherein the speed before testing and the speed after testing are both 1mm/s, the compression ratio is 40%, the trigger force is 5.0g, the time interval is 5s, and the compression is twice. Each sample was replicated 5 times. The specific test results are shown in Table 3.

TABLE 3

As seen from the data results of examples 1 to 15 in Table 3, the konjak tofu produced by using the modified konjak slurry of the invention had an elasticity value in the range of 2.23 to 3.24mm and a chewiness in the range of 2729.33 to 6505.3 g. The konjak tofu was more elastic and chewy than the data of comparative examples 1 to 5.

From the data results of examples 2 and 4-5, it is found that when the amount of the konjac flour is in the range of 620-710 g, the elasticity of the konjac tofu prepared from the modified konjac paste is 2.62-2.74 mm, and the chewiness is 3177.01-4709.43 g. It is fully shown that the use amount of the konjac powder directly influences the properties of the modified konjac powder, and the elasticity of the konjac tofu is reduced when the use amount of the konjac powder is too much or too little.

From the data results of example 2, examples 6-7, it is seen that wheat protein has an effect on the properties of the modified konjac syrup: when the amount of wheat protein is 18g, the elasticity value of the konjak tofu prepared from the modified konjak slurry is as high as 2.87mm, and the chewiness is 4865.54 g.

Further, examples 8 to 11 screened the effect of different edible gums on the modified konjac paste, and in the process, it was found that the edible gums used in these two schemes could better match with the other components in the modified konjac paste when the locust bean gum alone (example 6) or the gum arabic alone (example 10) was used, so that the elasticity of the prepared konjac tofu was better. Compared with the scheme of singly using guar gum (example 8) or using the xanthan gum and the guar gum in a composite manner (example 9), the obtained konjak tofu is more elastic and stiff.

Subsequently, the influence of the weight ratio of locust bean gum and gum arabic on the modified konjac syrup was further explored in examples 12-15: wherein, when the weight ratio of the locust bean gum to the Arabic gum is within the range of 1.2-2.6: 1 (examples 11 and 13-15), the obtained konjak tofu has larger elasticity and is more chewy.

Therefore, in conclusion, the components in the modified konjak slurry are mutually influenced, and the elasticity of the konjak tofu prepared by the modified konjak slurry is changed due to the use amounts of the konjak fine powder and the wheat protein; when the plant gum is selected from locust bean gum and Arabic gum, the elasticity of the konjak tofu is improved.

Comparison of the results of comparative example 1 and example 11 shows that the addition of amino acids is necessary for the elastic properties of the konjak tofu: when no amino acid is added, the elasticity of the konjak tofu prepared from the modified konjak slurry is as low as 2.01mm, and the chewiness is only 2564.60 g. When the amino acid is not added, the interaction between the wheat protein and the konjac powder is influenced, so that the effect of improving the elasticity of the wheat protein is obviously reduced.

The data results of comparative example 2 and example 11 show that the addition of edible gum has an influence on the quality of the modified konjac syrup. When no edible gum is added to the raw materials for preparing the modified konjak slurry, the elasticity of the konjak tofu prepared from the modified konjak slurry is as low as 1.54mm, and the chewiness is only 836.34 g. When the edible gum is not added, the interaction between the wheat protein and the konjac powder is influenced, so that the effect of improving the elasticity of the wheat protein is obviously reduced; meanwhile, as a substance for improving elasticity, it cannot exhibit its excellent elastic properties. Compared with amino acid, the edible gum has the effect of more remarkably improving the elasticity of the konjak tofu.

Comparative example 3 further explores the effect of wheat protein on the quality of modified konjac pulp when preparing modified konjac pulp. When wheat protein is not added to the raw material for preparing the modified konjak slurry, the elasticity of the konjak tofu prepared from the modified konjak slurry is remarkably reduced to 1.13mm, and the chewiness is only 795.06 g.

In comparative example 4, the elasticity, hardness, and chewiness of the konjak tofu prepared using the second-grade konjak powder obtained by general commercial use were far lower than those of the konjak tofu prepared using the modified konjak slurry of the present invention.

The data results of the comparative examples 1 to 3 show that, when the modified konjak pulp is prepared, the interaction among the wheat protein, the amino acid and the edible gum finally obviously improves the property of the konjak pulp, so that the strength and the elasticity of the konjak tofu prepared from the modified konjak pulp are obviously improved, and the taste of the konjak tofu is effectively improved.

Second, sensory evaluation

10 technicians capable of performing sensory evaluation of the konjak tofu were selected, and sensory evaluation was performed on the konjak tofu with the following numbers, and the evaluation criteria are shown in table 4. The average value of the evaluation of each item of the konjak tofu of each number by 10 evaluators was calculated, and the specific results are shown in table 5.

TABLE 4

Note that: in table 4, "small amount" means 3cm × 1.5cm × 1cm of the surface of the konjak tofu, the number of bubbles is 1 to 5, "large amount" means 6 to 15 bubbles, and "large amount" means more than 16 bubbles; the fine bubbles refer to bubbles with the diameter of less than 0.2 mm; the small bubbles refer to bubbles with the diameter of 0.2-0.5 mm; "mesoscopic bubbles" refers to bubbles having a bubble diameter of greater than 0.5 mm.

TABLE 5

As can be seen from the comparison of the data of example 2 and examples 6 to 11 in table 5, the konjak tofu produced by using the modified konjak slurry of the present invention has excellent sensory evaluation results, and the total score is in the range of 80 to 93. In particular, it is seen from the data results of examples 2 and 8 to 11 that the selection of different edible gums has certain influence on the mouthfeel, the tissue morphology and the color of the konjac tofu, wherein the influence on the mouthfeel of the konjac tofu is large. Finally, when locust bean gum and Arabic gum are selected to be mixed for use, the sensory evaluation result of the konjak tofu prepared by the modified konjak slurry is optimal.

On the other hand, as seen from the results of comparing the data of example 11 with that of comparative example 1, the addition of amino acids mainly affected the texture and texture of the konjak tofu when the modified konjak slurry was prepared, and when L-lysine was not added, the sensory evaluation of the konjak tofu prepared from the modified konjak slurry of comparative example 1 was low, and was only 70 points.

As can be seen from the results of comparing the data of example 11 and comparative example 2, the addition of the edible gum affects the taste, texture, and color of the konjak tofu when preparing the modified konjak slurry, and finally results in a lower sensory evaluation result of the konjak tofu prepared from the modified konjak slurry of comparative example 2, which is only 58 points.

The data results of comparative example 3 show that the taste of konjak tofu (taste evaluation value is only 14 points) is mainly affected by wheat protein when preparing modified konjak paste.

In terms of overall sensory evaluation, the konjac tofu prepared by the modified konjac paste has higher scores in comprehensive sensory evaluation of mouthfeel, tissue morphology, color and smell, and better taste experience.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. The modified konjak slurry is characterized by being prepared from the following raw materials in parts by weight: 55-78 parts of konjac fine powder, 0.6-3.3 parts of wheat protein, 0.1-0.6 part of amino acid, 0.3-1.5 parts of edible gum and water; the edible gum is selected from one or more of locust bean gum, guar gum, xanthan gum and acacia gum.

2. The modified konjak slurry of claim 1, wherein the modified konjak slurry is prepared from the following raw materials in parts by weight: 62-71 parts of konjac fine powder, 1.2-2.2 parts of wheat protein, 0.3-0.5 part of amino acid, 0.6-1.1 part of edible gum and water.

3. The modified konjak slurry of any one of claims 1 to 2, wherein the edible gum is locust bean gum and acacia gum.

4. The modified konjak slurry of claim 3, wherein the weight ratio of the locust bean gum to the gum arabic is (1.2 to 2.6): 1.

5. The modified konjak slurry according to any one of claims 1 to 2, wherein the weight ratio of the konjak powder to water is 1 (15 to 20).

6. The modified konjak slurry of claim 1, wherein the amino acid is one or both of L-lysine and L-arginine.

7. The method for producing a modified konjak slurry according to any one of claims 1 to 6, comprising the steps of:

s2, dissolving a certain amount of konjac powder in water, wherein the weight ratio of the konjac powder to the water is 1 (15-20), and then stirring at a constant temperature of 45-50 ℃ for 0.5-1 h to obtain basic konjac slurry;

8. The method for preparing modified konjac syrup according to claim 7, wherein the wheat protein liquid is prepared by the following steps: adding alkali to adjust the pH value of the water to 7.5-8, mixing the wheat protein and the water according to the weight ratio of (1-8) to 100, and uniformly stirring.

9. The method for preparing modified konjak slurry according to claim 7, wherein the amino acid solution is prepared by the steps of: adding alkali to adjust the pH value of the water to 7.5-8.5, mixing the amino acid and the water according to the weight ratio of (5-12) to 100, and uniformly stirring.

10. Use of the modified konjak slurry of any one of claims 1 to 6, wherein the modified konjak slurry is used for producing konjak foods such as konjak chips, konjak tofu, konjak shreds, konjak noodles, and konjak biomimetics.