Method for efficiently producing fresh and wet sweet potato vermicelli

Abstract

The invention discloses a method for efficiently producing fresh and wet sweet potato vermicelli, which comprises the following steps: S1, mixing sweet potato starch, thickening the sweet potato starch, mixing the well-blended sweet potato starch with dry starch and water, and rolling and kneading the mixture into a dough to obtain a sweet potato starch dough; s2, preparing the sweet potato starch dough into sweet potato vermicelli through a steaming and boiling process by adopting a powder leakage method; s3, soaking the sweet potato vermicelli in cooling water containing amylase; s4, putting the soaked sweet potato vermicelli into a freezer for freezing and aging; and S5, unfreezing the frozen and aged vermicelli under natural conditions to obtain the fresh and wet sweet potato vermicelli. According to the method, 10mg / kg alpha amylase solution is used, and the soaking time is 5 minutes. Under the treatment condition, the freezing and aging time of the vermicelli can be shortened to 16h from the original 24h, the unfreezing time is shortened to 6h from the original 12h, and the production efficiency is improved by more than 40%.

Description

Technical Field

[0001] The present invention relates to the technical field of sweet potato vermicelli production, and particularly relates to a method for efficiently producing fresh and wet sweet potato vermicelli. Background Art

[0002] Vermicelli is one of the common traditional foods in China and is also a starch processed food that people often consume in daily life. Common vermicelli is made from sweet potato starch, mung bean starch, potato starch, etc. Taking sweet potato vermicelli as an example: sweet potato starch contains many vitamins and dietary fibers and has relatively high nutritional value. The vermicelli made can provide various nutrients for the human body. Moreover, sweet potato vermicelli has toughness, a low paste soup rate, and a good taste, and is warmly welcomed by the public. Currently, the technological process of vermicelli production in the food industry is divided into the following steps: using potato starch or bean starch as raw materials, and making vermicelli through processes such as slurry mixing (paste making), forming (leaking vermicelli), cooling, drying or not drying (refrigerating or freezing).

[0003] A relatively common method is the vermicelli leaking method: thicken the sweet potato starch paste to make a dough with a certain fluidity. Then put the dough into a vermicelli leaking machine, and vermicelli with a certain shape and length can be leaked out. Subsequently, the vermicelli is steamed and gelatinized, and then put into cooling water to cool down, which can age and shape the vermicelli to a certain extent. Then, the cooled vermicelli is frozen and aged. After aging is completed, it is thawed. During the thawing process, the vermicelli will automatically disperse. Then, after a series of operations such as disinfection and sterilization and packaging, finally, commercial fresh and wet sweet potato vermicelli is made. After the sweet potato vermicelli is steamed and gelatinized, the remaining temperature inside is relatively high, and starch molecules will continuously precipitate to the surface of the vermicelli, resulting in a thick residue of starch paste on the surface of the vermicelli, and they will stick together before being frozen. During freezing and aging, due to the thick starch paste on the surface of the vermicelli, the re-formation speed of hydrogen bonds is slow, resulting in a slow aging speed. The vermicelli needs to be frozen for at least 24 hours to be completely aged and disperse smoothly during thawing. Through on-site investigation and statistics, the production of fresh and wet vermicelli requires at least 24 hours of freezing time and 12 hours of thawing time to carry out disinfection and packaging. The 36-hour waiting time greatly reduces the continuous production level of vermicelli production. If the freezing time of the vermicelli is shortened by one-third and the thawing time is shortened by half, the total time spent is about 22 hours. Taking a factory with a daily production of 25 tons of vermicelli as an example, the annual production difference of vermicelli products can reach more than 180 tons. After the factory improves the technology, the annual profit will increase by at least 3.6 million yuan. Therefore, reducing the viscosity of the cooked vermicelli and shortening the aging time of the vermicelli will greatly increase the factory's production capacity and efficiency, and can promote the development of the entire industry. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for efficiently producing fresh wet sweet potato vermicelli, so as to solve the problem in the prior art that the production process of fresh wet sweet potato vermicelli has a long vermicelli production cycle due to the long freezing aging time, resulting in a low continuous production level.

[0005] To achieve the above objectives, the present invention provides the following technical solutions: The present invention provides a method for efficiently producing fresh wet sweet potato vermicelli, comprising the following steps: S1. slurrying and thickening the sweet potato starch, mixing the thickened starch with dry starch and water, and rolling and kneading them into a dough to obtain a sweet potato starch dough; S2, using the powder leakage method, the sweet potato starch mass in S1 is made into sweet potato vermicelli through a steaming process; S3, soaking the sweet potato vermicelli obtained in S2 in cooling water containing amylase; S4, placing the sweet potato vermicelli soaked in S3 into a freezer for freeze aging; S5. Thawing the frozen and aged vermicelli in S4 under natural conditions to obtain fresh wet sweet potato vermicelli.

[0006] Furthermore, the method further includes sterilizing and aseptically packaging the fresh wet sweet potato vermicelli; the sterilization adopts high-temperature short-time sterilization, and the sterilization condition is heating at 95° C. for 15 seconds; and the aseptic packaging adopts vacuum packaging.

[0007] Furthermore, during the slurry preparation in S1, the water content of the starch slurry formed by mixing dry sweet potato starch and water is maintained at 45-55%, and the slurry preparation water temperature is 20-30°C; during the thickening, the water content of the starch slurry is maintained at 85-90%, the water temperature is 100°C, and the starch slurry obtained by thickening is a gray transparent gel.

[0008] Furthermore, when rolling and kneading into a dough in S1, the mass ratio of water to starch is 2:1, the mass ratio of dry starch to water is 1:2, and the water temperature is maintained between 40-50°C.

[0009] Furthermore, during the cooking process in S2, the temperature is controlled at 100° C., and the cooking time is controlled at 1-2 minutes.

[0010] Furthermore, the amylase in S3 is α-amylase, and its concentration is 10 mg / kg; the sweet potato vermicelli is soaked in cooling water containing amylase for 5 minutes, and the cooling water temperature is 18-22°C.

[0011] Furthermore, the freezing temperature in S4 is -3°C to -5°C, and the freezing time is 16 hours.

[0012] Amylase is a class of enzymes that can hydrolyze starch into dextrin, maltose and other substances with smaller molecular weights. At present, most of the research on amylase is applied in the fields of biology, medicine, new food industry, etc., but there are few reports on its application in the traditional vermicelli industry. Due to its good starch hydrolysis characteristics, it is a good choice for the pretreatment of vermicelli aging. By adding a certain amount of amylase to the cooling water, when the vermicelli is put into the cooling water after being cooked, the amylase molecules can degrade the starch molecules precipitated on the surface of the vermicelli during the cooling process, greatly reducing the thickness of the starch paste on the surface of the vermicelli, decreasing the adhesiveness, and significantly increasing the aging speed, so that the production cycle of each batch of vermicelli is shortened, thereby improving the continuous production efficiency of vermicelli and the production efficiency of the enterprise.

[0013] Based on the above technical solutions, the embodiments of the present invention can at least produce the following technical effects: (1) A method for efficiently producing fresh and wet sweet potato vermicelli provided by the present invention uses an α-amylase solution with a concentration of 10 mg / kg, and the soaking time is 5 min. Under these treatment conditions, the freezing and aging time of the vermicelli can be shortened from the original 24 h to 16 h, and the thawing time can be shortened from the original 12 h to 6 h, and the production efficiency is increased by more than 40%.

[0014] (2) A method for efficiently producing fresh and wet sweet potato vermicelli provided by the present invention. Compared with the vermicelli produced normally, the vermicelli treated with amylase does not show significant differences in texture quality and cooking characteristics, and the quality of the treated vermicelli will not decrease. For the same amylase, changing the concentration of the solution or the soaking time basically does not cause significant changes in the various indexes of texture quality and the various indexes of cooking characteristics, and the differences are not significant. For the cost, α-amylase is relatively common on the market at present, and the selling price is low, and the usage cost is far less than the profit obtained after technical improvement. Therefore, it can be considered that using the enzyme solution not only accelerates the freezing and aging speed of the vermicelli, but also its quality does not decrease compared with the vermicelli produced normally, achieving the expected goal of the experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0016] Figure 1 It is the result diagram of the water absorption rate of vermicelli under different enzyme solution concentrations in Embodiment 1 of the present invention; Figure 2 It is the result diagram of the total cooking loss of vermicelli under different enzyme solution concentrations in Embodiment 1 of the present invention; Figure 3 It is the result diagram of the expansion degree of vermicelli under different enzyme solution concentrations in Embodiment 1 of the present invention; Figure 4 It is the result diagram of the expansion degree of vermicelli under different soaking time treatments in Embodiment 2 of the present invention; Figure 5 It is the result diagram of the expansion degree of vermicelli under different soaking time treatments in Embodiment 2 of the present invention; Figure 6 It is the result diagram of the expansion degree of vermicelli under different soaking time treatments in Embodiment 2 of the present invention. Detailed implementation manners

[0017] Now, various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and implementation schemes of the present invention.

[0018] It should be understood that the terms described in the present invention are only for describing specific implementation manners and are not used to limit the present invention. In addition, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range and each smaller range between any other stated value or intermediate value within the stated range are also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0019] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0020] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific implementation manners of the present invention specification, which are obvious to those skilled in the art. Other implementation manners obtained from the specification of the present invention are obvious to those skilled in the art. The specification and embodiments of the present invention are only exemplary.

[0021] Regarding the terms "comprising", "including", "having", "containing", etc. used herein, they are all open-ended terms, that is, they are meant to include but not limited to.

[0022] Embodiment 1 A method for efficiently producing fresh and wet sweet potato vermicelli, comprising the following steps: (1)Mix sweet potato starch to make slurry, thicken it, and knead it into a dough to obtain sweet potato starch dough. During the slurry-making process, the water content in the starch slurry formed by mixing dry starch and water should be maintained at about 50%, and the slurry-making water temperature is 20 - 30°C. During the thickening process, the water content of the starch paste should be maintained at about 87.5%, the water temperature for thickening should be 100°C, and the starch paste should be a grayish transparent gel. The process of kneading into a dough is a process of kneading the thickened starch paste with dry starch and water. Among them, the ratio of water to starch paste is 2:1, the ratio of dry starch to water is 1:2, and the water temperature is maintained between 40 - 50°C. After kneading into a dough, the sweet potato starch dough should be as smooth as dough, non-sticky, and can flow evenly without breaking.

[0023] (2)Adopt the method of leaking powder and make the sweet potato starch dough into sweet potato vermicelli through the steaming process. During the steaming process, the steaming temperature is controlled at 100°C, and the steaming time is controlled between 1 - 2 minutes.

[0024] (3)Soak the sweet potato vermicelli in cooling water containing amylase. The type of amylase is α-amylase, the concentration is 10 mg / kg, the soaking time is 5 minutes, and the cooling water temperature is about 20°C.

[0025] (4)Put the soaked sweet potato vermicelli into the freezer for freezing and aging. The freezing temperature is -3 - -5°C, and the freezing time is 16 hours.

[0026] (5)Thaw the frozen and aged vermicelli under natural conditions to obtain fresh and wet sweet potato vermicelli, and the thawing time is about 6 hours.

[0027] (6)The subsequent method also includes further processing the obtained rice noodles such as sterilization and aseptic packaging. Among them, high-temperature short-time sterilization is adopted, and the sterilization conditions are heating at 95°C for 15 s; aseptic packaging adopts vacuum packaging treatment.

[0028] Effect of different enzyme solution concentrations on the cooking characteristics of vermicelli: Put the sweet potato vermicelli in (3) into cooling water without amylase for soaking, and the rest is the same as the above preparation method. The fresh and wet sweet potato vermicelli prepared is used as the normal batch; A1: Soak in 10 mg / kg α-amylase solution for 5 minutes; A2: Soak in 20 mg / kg α-amylase solution for 5 minutes; A3: Soak in 40 mg / kg α-amylase solution for 5 minutes; B1: Soak in 10 mg / kg β-amylase solution for 5 minutes; B2: Soak in 20 mg / kg β-amylase solution for 5 minutes; B3 represents soaking in 40 mg / kg β-amylase solution for 5 minutes.

[0029] The water absorption rate, total cooking loss, and swelling degree of fresh and wet sweet potato vermicelli in normal batches, groups A1, A2, A3, B1, B2, and B3 were tested, and the results are as Figures 1 - 3 shown.

[0030] It can be Figures 1 - 3 seen that when other conditions are the same, compared with the sweet potato vermicelli produced by the normal process, the sweet potato vermicelli made after soaking treatment at different concentrations have basically no significant differences in water absorption rate, total cooking loss, and swelling degree. This shows that treatment with amylase solution will not affect the quality of the vermicelli, and changing the concentration of the amylase solution will not cause differences in the quality of the vermicelli either. In this case, choosing the condition with a lower amylase concentration is more conducive to cost savings and can also achieve the effect of shortening the freezing and aging time.

[0031] Example 2 Effect of different soaking times on the cooking characteristics of sweet potato vermicelli: Put the (3) sweet potato vermicelli into cool water without amylase for soaking, and the rest is the same as the preparation method in Example 1. The fresh and wet sweet potato vermicelli prepared are used as the normal batch; A1: Soak in 10 mg / kg α-amylase solution for 5 min; A2: Soak in 10 mg / kg α-amylase solution for 10 min; B1: Soak in 10 mg / kg β-amylase solution for 5 min; B2: Soak in 10 mg / kg β-amylase solution for 10 min; The water absorption rate, total cooking loss, and swelling degree of the fresh and wet sweet potato vermicelli in normal batches, groups A1, A2, B1, and B2 were tested, and the results are as Figures 4 - 6 shown.

[0032] It can be Figures 4 - 6 seen that when other conditions are the same, compared with the sweet potato vermicelli produced by the normal process, the sweet potato vermicelli made after different soaking times have basically no significant differences in water absorption rate, total cooking loss, and swelling degree. This shows that treatment with amylase solution will not affect the quality of the vermicelli, and within a certain range, changing the soaking time of the amylase solution will not cause differences in the quality of the vermicelli either. In this case, choosing the condition with a shorter soaking time is more conducive to cost savings and can also achieve the effect of shortening the freezing and aging time.

[0033] Example 3 Effect of treatment with amylase solutions at different concentrations on the texture quality of sweet potato vermicelli, and the results are shown in Table 1: Table 1 As can be seen from Table 1, for the α-amylase treatment group, with the increase in the concentration of the enzyme solution, except that the chewiness is better, other texture indexes do not change significantly. For the β-amylase treatment group, with the increase in the concentration of the enzyme solution, all texture indexes do not change significantly. By comparing with the control group, it is found that almost all the viscosities of the experimental groups are significantly lower than that of the control group, and there are no obvious differences between the experimental groups and the control group in other indexes. This also shows that after treating the vermicelli with amylase, the viscosity of the vermicelli can be significantly reduced, and it will not have an obvious impact on the texture quality of the vermicelli. For the vermicelli made after soaking in 10 mg / kg α-amylase solution for 5 min, except that the cohesiveness is significantly higher than that of the control group, other indexes have no significant differences from the control group. And the cohesiveness reflects the strength of the internal structure of the vermicelli. The higher the value, the higher the strength and the better the taste during eating. Therefore, the quality of the vermicelli remains good under the treatment of soaking in 10 mg / kg α-amylase solution for 5 min.

[0034] Example 4 The influence of different soaking times on the texture quality of sweet potato vermicelli is shown in Table 2 as follows: Table 2 As can be seen from Table 2, when the concentration of amylase is the same, for α-amylase, the longer the soaking time, the smaller the hardness and gumminess, and the better the quality of the vermicelli; for β-amylase, the longer the soaking time, there are no significant differences in each texture characteristic index, and it is considered that the change of the soaking time has no significant impact on the quality of the vermicelli. There are no significant differences in the elasticity, chewiness and gumminess of the vermicelli in the normal group and all experimental groups, and the quality remains relatively good; while there are differences in the hardness, viscosity and cohesiveness of the vermicelli in the normal group and the experimental groups. The hardness of the α-amylase treatment group is generally smaller than that of the β-amylase treatment group, and there are significant differences with some of the normal group; in terms of viscosity, the viscosities of all experimental groups are significantly smaller than that of the normal group, and in terms of cohesiveness, the vermicelli after β-amylase treatment has stronger cohesiveness. Generally speaking, the quality of the vermicelli after α-amylase treatment is better.

[0035] Finally, it should be noted that: The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for efficiently producing fresh and wet sweet potato vermicelli, characterized in that, It includes the following steps: S1. Adjust the sweet potato starch into a slurry and thicken it. Mix the thickened starch paste with dry starch and water, and knead them into a dough to obtain a sweet potato starch dough; S2. Adopt the method of leaking powder, and make the sweet potato starch dough in S1 into sweet potato vermicelli through a steaming process; S3. Immerse the sweet potato vermicelli obtained in S2 in the cooling water containing amylase; S4. Put the sweet potato vermicelli soaked in S3 into a freezer for freezing and aging; S5. Thaw the sweet potato vermicelli after freezing and aging in S4 under natural conditions to obtain fresh and wet sweet potato vermicelli.

2. The method for efficiently producing fresh and wet sweet potato vermicelli according to claim 1, characterized in that, It also includes subsequent sterilization and aseptic packaging treatment of the fresh and wet sweet potato vermicelli; the sterilization adopts high-temperature short-time sterilization, and the sterilization conditions are heating at 95°C for 15 s; the aseptic packaging adopts vacuum packaging treatment.

3. The method for efficiently producing fresh and wet sweet potato vermicelli according to claim 1, characterized in that, When adjusting the slurry in S1, the water content in the starch slurry formed by mixing dry sweet potato starch and water is maintained at 45-55%, and the slurry-adjusting water temperature is 20-30°C; when thickening, the water content of the starch paste is maintained at 85-90%, the water temperature is 100°C, and the thickened starch paste is in the form of a gray transparent gel.

4. The method for efficiently producing fresh wet sweet potato vermicelli according to claim 1, characterized in that, When kneading into a dough in S1, the mass ratio of water to the starch paste is 2:1, the mass ratio of dry starch to water is 1:2, and the water temperature is maintained between 40-50°C.

5. The method for efficiently producing fresh and wet sweet potato vermicelli according to claim 1, characterized in that, During the steaming process in S2, the temperature is controlled at 100°C, and the steaming time is controlled at 1-2 min.

6. The method for efficiently producing fresh and wet sweet potato vermicelli according to claim 1, characterized in that, The amylase in S3 is α-amylase, and its concentration is 10 mg / kg; the soaking time of the sweet potato vermicelli in the cooling water containing amylase is 5 min, and the cooling water temperature is 18-22°C.

7. The method for efficiently producing fresh wet sweet potato vermicelli according to claim 1, characterized in that, The freezing temperature in S4 is -3°C to -5°C, and the freezing time is 16 h.

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