Preparation method of low-bacterium wheat flour and low-bacterium wheat flour

Abstract

The invention provides a preparation method of low-bacterium wheat flour and the low-bacterium wheat flour, and the preparation method of the low-bacterium wheat flour comprises the following steps: preparing a mixed solution containing bacteriophage lyase, phenyllactic acid and water; mixing the mixed solution with wheat, and sequentially standing and centrifugally filtering; the wheat obtained after centrifugal filtration is subjected to wheat wetting and flour milling in sequence. According to the production method of the low-bacterium wheat flour, the total number of bacterial colonies of the wheat flour can be controlled to be 380 cfu / g or below, the content of mould and saccharomycetes can be controlled to be 100 cfu / g, the requirements of customers and the market for the low-bacterium wheat flour are met, the quality of the wheat flour is not damaged, and the bacterium content of processed by-products is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of grain processing, and in particular to a preparation method of low-bacteria wheat flour and the low-bacteria wheat flour. Background Art

[0002] In the related technology, physical and / or chemical methods are mostly used to prepare low-bacteria wheat flour. However, the quality of wheat is easily damaged when sterilized by heat treatment methods such as steam and microwaves; ultraviolet light, pulsed light, etc. have poor penetration and low sterilization efficiency; electrolyzed water is unstable and has poor mold inhibition effect; ozone water-moistened wheat is prone to produce odor, and the fatty acid value of wheat increases when the treatment time is long. In addition, ozone has poor stability, certain toxicity and is easy to explode; chlorine dioxide is unstable and decomposes even in a dark environment. The effective bactericidal components of the chlorine dioxide solution decompose, causing its bactericidal effect to weaken over time.

[0003] Therefore, there is an urgent need to provide a method for preparing low-bacteria wheat flour that has good antibacterial effect, does not damage wheat quality and has high safety. Summary of the invention

[0004] Based on this, the present application provides a method for preparing low-bacteria wheat flour and low-bacteria wheat flour which has good antibacterial effect, will not damage wheat quality and has high safety.

[0005] The first aspect of the present application provides a method for preparing low-bacteria wheat flour, comprising the following steps:

[0006] preparing a mixed solution comprising bacteriophage lytic enzyme, phenyllactic acid and water;

[0007] The mixed solution is mixed with wheat, and then allowed to stand and centrifuged and filtered;

[0008] The wheat obtained after centrifugal filtration is sequentially tempered and floured.

[0009] In some embodiments, the mass ratio of the bacteriophage lytic enzyme, phenyllactic acid and water is (1-5):(50-200):10000.

[0010] In some embodiments, the mass ratio of the mixed solution to the wheat is (0.5-2):1.

[0011] In some embodiments, the standing time is 5 min-60 min.

[0012] In some embodiments, the centrifugation speed is 500 rpm-20000 rpm.

[0013] In some embodiments, the centrifugation time is 1 min-30 min.

[0014] In some embodiments, the temperature of tempering the wheat is 15°C-30°C.

[0015] In some embodiments, the wheat tempering time is 4h-8h.

[0016] In some embodiments, the moisture content of the wheat obtained after centrifugal filtration is 15wt%-17wt%.

[0017] The second aspect of the present application provides a low-bacteria wheat flour prepared by the preparation method of the first aspect of the present application.

[0018] The method for preparing low-bacteria wheat flour provided above adopts a mixed solution of bacteriophage lytic enzyme, phenyllactic acid and water combined with centrifugal filtration to temper the wheat. During the standing process of the wheat and the mixed solution, the bacteriophage lytic enzyme and phenyllactic acid synergistically act on the cell wall, cell membrane and nucleic acid of the microorganisms, inhibit the growth and reproduction of bacteria and molds in the wheat bran and wheat ventral groove, degrade fungal mycin, and reduce the content of microorganisms. Further, the microorganisms attached to the wheat epidermis can be effectively separated by centrifugation. At the same time, the wheat mixed solution is impacted during the centrifugation process, which destroys the integrity of the wheat cortex, shortens the route for water molecules to enter the endosperm, and shortens the tempering time.

[0019] The production method of low-bacteria wheat flour provided in the present application can control the total colony count of wheat flour to below 380 cfu / g, and the content of mold and yeast can be controlled to below 100 cfu / g, meeting the needs of customers and the market for low-bacteria flour without damaging the quality of wheat flour, and reducing the bacterial content of processing by-products. Compared with the traditional wheat moistening method, the wheat moistening time takes up to 18h-24h. The preparation method of low-bacteria wheat flour provided in the present application can significantly shorten the wheat moistening time to 4h-8h, significantly improve production efficiency, and simplify the operation steps. Compared with chemical sterilization technologies such as ozone water and chlorine dioxide sterilization, this solution uses physical combined with biotechnology, bacteriophages are easy to degrade, no harmful products are produced in actual operation, and no harmful gases are produced. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application and to more completely understand the present application and its beneficial effects, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0021] Figure 1 The present invention is a flow chart of a method for preparing low-bacteria wheat flour provided in one embodiment. DETAILED DESCRIPTION

[0022] For ease of understanding of the present application, the present application will be described more fully below with reference to the relevant embodiments. The following provides preferred embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0024] The terms "and / or", "or / and", and "and / or" used herein include any one of two or more related listed items, and also include any and all combinations of the related listed items, wherein the any and all combinations include any combination of two related listed items, any more related listed items, or all related listed items. It should be noted that when at least three items are connected by at least two conjunctions selected from "and / or", "or / and", and "and / or", it should be understood that in the present application, the technical solution undoubtedly includes technical solutions connected by "logical and", and also undoubtedly includes technical solutions connected by "logical or".

[0025] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0026] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0027] Only some numerical ranges are specifically disclosed herein. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, and likewise any upper limit can be combined with any other upper limit to form an unspecified range. In addition, each separately disclosed point or single value can itself be combined as a lower limit or upper limit with any other point or single value or with other lower limits or upper limits to form an unspecified range.

[0028] The temperature parameters in this application, unless otherwise specified, allow both constant temperature treatment and treatment within a certain temperature range. The constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are allowed.

[0029] Herein, the “suitable” mentioned in “suitable combination”, “suitable method”, “any suitable method”, etc., shall be based on the ability to implement the technical solution of this application, solve the technical problems of this application, and achieve the expected technical effects of this application.

[0030] In the present application, "further", "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present application.

[0031] In this application, "optionally", "optional", and "optional" mean optional or dispensable, that is, any one of the two parallel schemes of "yes" or "no". If multiple "options" appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent.

[0032] In the description of the application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] If there is no special description, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution. If there is no special description, all technical features and optional technical features of the present application can be combined with each other to form a new technical solution.

[0034] If there is no special explanation, all the steps of the present application can be performed sequentially or randomly, preferably sequentially.

[0035] In the related technology, physical and / or chemical methods are mostly used to prepare low-bacteria wheat flour. However, the quality of wheat is easily damaged when sterilized by heat treatment methods such as steam and microwaves; ultraviolet light, pulsed light, etc. have poor penetration and low sterilization efficiency; electrolyzed water is unstable and has poor mold inhibition effect; ozone water-moistened wheat is prone to produce odor, and the fatty acid value of wheat increases when the treatment time is long. In addition, ozone has poor stability, certain toxicity and is easy to explode; chlorine dioxide is unstable and decomposes even in a dark environment. The effective bactericidal components of the chlorine dioxide solution decompose, causing its bactericidal effect to weaken over time.

[0036] The Chinese patent application with publication number CN113841734A discloses the use of stable chlorine dioxide for moistening wheat. After the stable chlorine dioxide is activated, chlorine dioxide gas molecules are generated. Chlorine dioxide has a pungent odor and irritates the eyes and respiratory tract, which is dangerous in actual use.

[0037] Therefore, there is an urgent need to provide a method for preparing low-bacteria wheat flour that has good antibacterial effect, does not damage wheat quality and has high safety.

[0038] Based on the above problems, the present application firstly utilizes the centrifugal filtration principle to effectively separate wheat epidermal microorganisms during the wheat tempering process, firstly utilizes bacteriophage lytic enzymes to effectively kill wheat ventral groove and epidermal bacteria during the wheat tempering process, and firstly utilizes phenyllactic acid to degrade fungal toxins during the wheat tempering process and kill mold at the same time; under the premise of not damaging the quality of wheat flour and its by-products, centrifugal filtration technology is used in conjunction with biological enzymes and organic acids to reduce the content of wheat bran microorganisms, shorten the wheat tempering time, and obtain a wheat flour with a colony content of 10 3 Low-bacteria wheat flour with less than cfu / g.

[0039] One or more embodiments of the present application provide a method for preparing low-bacteria wheat flour, comprising the following steps: preparing a mixed solution comprising bacteriophage lytic enzyme, phenyllactic acid and water; mixing the mixed solution with wheat, and then allowing the mixed solution to stand and centrifugally filtering the mixed solution; and tempering and milling the wheat obtained after centrifugation.

[0040] Understandably, the method for preparing low-bacteria wheat flour uses a mixed solution of bacteriophage lytic enzyme, phenyllactic acid and water combined with centrifugal filtration to moisten the wheat. During the static process of wheat and the mixed solution, the bacteriophage lytic enzyme and phenyllactic acid synergistically act on the cell wall, cell membrane and nucleic acid of the microorganisms, inhibit the growth and reproduction of bacteria and molds in the wheat bran and wheat ventral groove, degrade fungal mycin, and reduce the content of microorganisms. Further, the microorganisms attached to the wheat epidermis can be effectively separated by centrifugation. At the same time, the wheat mixed solution is impacted during the centrifugation process, which destroys the integrity of the wheat cortex, shortens the route for water molecules to enter the endosperm, and shortens the moistening time.

[0041] The production method of low-bacteria wheat flour provided in the present application can control the total colony count of wheat flour to below 380 cfu / g, and the content of mold and yeast can be controlled to below 100 cfu / g, meeting the needs of customers and the market for low-bacteria flour without damaging the quality of wheat flour, and reducing the bacterial content of processing by-products. Compared with the traditional wheat moistening method, the wheat moistening time takes up to 18h-24h. The preparation method of low-bacteria wheat flour provided in the present application can significantly shorten the wheat moistening time to 4h-8h, significantly improve production efficiency, and simplify the operation steps. Compared with chemical sterilization technologies such as ozone water and chlorine dioxide sterilization, this solution uses physical combined with biotechnology, bacteriophages are easy to degrade, no harmful products are produced in actual operation, and no harmful gases are produced.

[0042] In some embodiments, before the step of mixing the mixed solution with the wheat, the preparation method further comprises: removing impurities from the wheat.

[0043] Figure 1 A schematic diagram of the preparation process of low-bacteria wheat flour provided in one embodiment, comprising Figure 1 It can be seen that when preparing low-bacteria wheat flour, first prepare a mixed solution containing bacteriophage lytic enzyme, phenyllactic acid and water; mix the mixed solution with the cleaned wheat and then let it stand and centrifuge it in sequence; put the wheat obtained after centrifugal filtration into a warehouse for standing and tempering, and after the standing and tempering, use a flour milling system to grind the wheat and collect wheat flour.

[0044] In some embodiments, the mass ratio of bacteriophage lytic enzyme, phenyllactic acid and water is (1-5): (50-200): 10000; for example, it can be but not limited to (1-5): (50-200): 10000, (1-4.5): (50-180): 10000, (1-4): (50-160): 10000, (1-3.5): (50-140): 10000, (1-3): (50-120): 10000 or (1-3): (50-100): 1000, etc. When the mass ratio of bacteriophage lytic enzyme, phenyllactic acid and water is within the above range, wheat epidermal bacteria and fungal microorganisms can be effectively killed without excessive use causing increased costs.

[0045] As a possible implementation, the mass ratio of the mixed solution to the wheat is (0.5-2):1; for example, it can be, but is not limited to, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1 or a range between any two of the above mass ratios. When the mass ratio of the mixed solution to the wheat is within the above range, the wheat can be fully contacted with the mixed solution, which is convenient for killing wheat microorganisms, and at the same time, excessive use will not cause waste of solution and increase costs.

[0046] In some embodiments, the standing time is 5 min-60 min; for example, it can be but not limited to 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min or a range between any two of the above time periods, etc. When the standing time is within the above range, wheat microorganisms can be effectively killed, and at the same time, water cannot penetrate into the interior of the wheat, which is convenient for subsequent centrifugal separation.

[0047] As a possible embodiment, the centrifugal speed is 500rpm-20000rpm; for example, it can be but not limited to 500rpm, 1000rpm, 2000rpm, 3000rpm, 4000rpm, 5000rpm, 6000rpm, 7000rpm, 8000rpm, 9000rpm, 10000rpm, 11000rpm, 12000rpm, 13000rpm, 14000rpm, 15000rpm, 16000rpm, 17000rpm, 18000rpm, 19000rpm, 20000rpm or the range between any two of the above speeds, etc. When the centrifugal speed is within the above range, wheat and microorganisms can be fully separated, the microbial content of wheat can be effectively reduced, the wheat cortex can be appropriately broken, and the wheat tempering process can be accelerated.

[0048] In some embodiments, the centrifugation time is 1 min-30 min; for example, it can be but not limited to 1 min, 2 min, 4 min, 6 min, 8 min, 10 min, 12 min, 14 min, 16 min, 18 min, 20 min or a range between any two of the above times, etc. When the centrifugation time is within the above range, the wheat and the microorganisms can be fully separated, the microbial content of the wheat can be effectively reduced, the wheat cortex can be appropriately broken, and the wheat tempering process can be accelerated.

[0049] It should be noted that the centrifugal speed and time can be combined in any suitable manner, and both can be selected from any centrifugal speed and time described in this article.

[0050] As a possible implementation, the temperature of tempering the wheat is 15° C.-30° C. For example, it may be, but is not limited to, 15° C., 16° C., 17° C., 18° C., 19° C., 20° C., 21° C., 22° C., 23° C., 24° C., 25° C., or a range between any two of the above temperatures.

[0051] In some embodiments, the time for tempering the wheat is 4 hours to 8 hours; for example, it can be but is not limited to 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours or a range between any two of the above times.

[0052] In some embodiments, the moisture content of the wheat obtained after centrifugal filtration is 15wt%-17wt%; for example, it can be but not limited to 15wt%, 15.5wt%, 16wt%, 16.5wt%, 17wt% or a range between any two of the above moisture contents.

[0053] One or more embodiments of the present application provide a low-bacteria wheat flour, which is prepared using the above-mentioned method for preparing low-bacteria wheat flour.

[0054] The low-microorganism wheat flour provided in the present application has a total colony count of less than 380 cfu / g, a mold and yeast content of less than 100 cfu / g, the wheat quality is not damaged, and the bacterial content of processing by-products is low, which can meet the needs of customers and the market for low-microorganism flour.

[0055] The technical scheme of the present application is described in detail below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present application and are not used to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following embodiments are preferably referred to the guidance given in the present application, and can also be carried out according to the experimental manual or conventional conditions in the field, or according to the conditions recommended by the manufacturer, or with reference to experimental methods known in the art.

[0056] In the following specific embodiments, the measured parameters of raw material components may have slight deviations within the range of weighing accuracy unless otherwise specified. For temperature and time parameters, acceptable deviations caused by instrument test accuracy or operation accuracy are allowed.

[0057] 1. Preparation of low-bacteria wheat flour

[0058] Example 1

[0059] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 1:50:10000;

[0060] Step S2, cleaning and removing the impurities from the wheat for later use;

[0061] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 10 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0062] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0063] Example 2

[0064] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 3:50:10000;

[0065] Step S2, cleaning and removing the impurities from the wheat for later use;

[0066] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 20 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0067] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0068] Example 3

[0069] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 3:50:10000;

[0070] Step S2, cleaning and removing the impurities from the wheat for later use;

[0071] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 30 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 3000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0072] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 5 hours before milling.

[0073] Example 4

[0074] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 3:100:10000;

[0075] Step S2, cleaning and removing the impurities from the wheat for later use;

[0076] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 20 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 3000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0077] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 5 hours before milling.

[0078] Example 5

[0079] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 3:100:10000;

[0080] Step S2, cleaning and removing the impurities from the wheat for later use;

[0081] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 20 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 4000 r / min and a centrifugation time of 6 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0082] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 4 hours before milling.

[0083] Example 6

[0084] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 5:50:10000;

[0085] Step S2, cleaning and removing the impurities from the wheat for later use;

[0086] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 10 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0087] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0088] Example 7

[0089] The preparation method of Example 7 is similar to the preparation method of Example 1, except that the mass ratio of bacteriophage lytic enzyme, phenyllactic acid and water in step S1 of Example 7 is different, and the others are the same. The details of Example 7 are as follows:

[0090] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 1:100:10000;

[0091] Step S2, cleaning and removing the impurities from the wheat for later use;

[0092] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 10 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0093] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0094] Example 8

[0095] The preparation method of Example 8 is similar to the preparation method of Example 1, except that the mass ratio of bacteriophage lytic enzyme, phenyllactic acid and water in step S1 of Example 8 is different, and the others are the same. The details of Example 8 are as follows:

[0096] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 1:200:10000;

[0097] Step S2, cleaning and removing the impurities from the wheat for later use;

[0098] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 10 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0099] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0100] Example 9

[0101] The preparation method of Example 9 is similar to the preparation method of Example 1, except that the mass ratio of the mixed solution to wheat in step S3 of Example 9 is different, and the others are the same. The details of Example 9 are as follows:

[0102] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 1:50:10000;

[0103] Step S2, cleaning and removing the impurities from the wheat for later use;

[0104] Step S3, mixing the prepared mixed solution with wheat at a mass ratio of 0.5:1 and letting it stand for 10 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0105] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0106] Example 10

[0107] The preparation method of Example 10 is similar to the preparation method of Example 1, except that the mass ratio of the mixed solution to wheat in step S3 of Example 10 is different, and the others are the same. The details of Example 10 are as follows:

[0108] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 1:50:10000;

[0109] Step S2, cleaning and removing the impurities from the wheat for later use;

[0110] Step S3, mixing the prepared mixed solution with wheat at a mass ratio of 2:1 and letting it stand for 10 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0111] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0112] Comparative Example 1

[0113] The difference between the preparation method of comparative example 1 and the preparation method of embodiment 3 is that water is used to replace the mixed solution in comparative example 1. The specific preparation method of comparative example 1 is as follows:

[0114] Step S1, cleaning and removing impurities from the wheat for later use.

[0115] Step S2, mixing tap water and wheat in a mass ratio of 1:1 and letting it stand for 30 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 3000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0116] Step S3: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 5 hours before milling.

[0117] Comparative Example 2

[0118] The main difference between the preparation method of comparative example 2 and the preparation method of embodiment 2 is that in step S3 of comparative example 2, the mixed solution and wheat are mixed and then vibrated. The preparation method of comparative example 2 is as follows:

[0119] Step S1, uniformly preparing a mixed solution according to the mass ratio of bacteriophage lytic enzyme: phenyllactic acid: water = 3:50:10000;

[0120] Step S2, cleaning and removing the impurities from the wheat for later use;

[0121] Step S3, the prepared mixed solution and wheat are irrigated by a vibration irrigating machine, and the moisture content of the wheat is increased to 16% after the vibration is completed.

[0122] Step S4: After the vibration is completed, the wheat is put into the wheat tempering bin and left to temper for 12 hours before milling.

[0123] Comparative Example 3

[0124] Step S1, cleaning and removing impurities from the wheat for later use.

[0125] Step S2: Mix 10 mg / L ozone water with wheat and vibrate until the moisture content of the wheat is 16%.

[0126] Step S3: After the vibration is completed, the wheat enters the wheat tempering bin and is left to temper for 12 hours before being milled.

[0127] Comparative Example 4

[0128] Step S1, cleaning and removing impurities from the wheat for later use.

[0129] Step S2: Mix 10 mg / L chlorine dioxide with wheat and vibrate until the moisture content of the wheat is 16%.

[0130] Step S3: After the vibration is completed, the wheat enters the wheat tempering bin and is left to temper for 12 hours before being milled.

[0131] Comparative Example 5

[0132] The difference between Comparative Example 5 and Example 2 is that the mixed solution in step S1 of Comparative Example 5 does not contain bacteriophage lytic enzyme, and the other parts are the same. The specific preparation method of Comparative Example 5 includes:

[0133] Step S1, uniformly preparing a mixed solution according to a mass ratio of phenyllactic acid: water = 50:10000;

[0134] Step S2, cleaning and removing the impurities from the wheat for later use;

[0135] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 20 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0136] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0137] Comparative Example 6

[0138] The difference between Comparative Example 6 and Example 2 is that the mixed solution in step S1 of Comparative Example 6 does not contain phenyllactic acid, and the other aspects are the same. The specific preparation method of Comparative Example 6 includes:

[0139] Step S1, uniformly preparing a mixed solution according to a mass ratio of bacteriophage lytic enzyme: water = 3:10000;

[0140] Step S2, cleaning and removing the impurities from the wheat for later use;

[0141] Step S3, mixing the prepared mixed solution with wheat in a mass ratio of 1:1 and letting it stand for 20 minutes. After the standing, the mixture enters a filtering centrifuge at a speed of 1000 r / min and a centrifugation time of 10 minutes. After high-speed centrifugation, the moisture content of the wheat increases to 16%.

[0142] Step S4: After centrifugal filtration is completed, the wheat is placed in a wheat tempering bin and allowed to stand for 6 hours before milling.

[0143] Comparative Example 7

[0144] After the wheat is cleaned and dusted, it is sprayed with water until the moisture content of the wheat is 16%. After the wheat is watered, it is left to stand at 25℃ for 20 hours before flour making.

[0145] 2. Determination of microbial indicators

[0146] The total number of fungi and the content of molds and yeasts were measured for the wheat flour prepared in the above embodiments and comparative examples, wherein the total number of colonies refers to GB 4789.2-2022; the molds and yeasts refer to GB 4789.15-2016. The test results are shown in Table 1.

[0147] Table 1

[0148]

[0149] From the comparison of the results of Examples 1-10 and Comparative Examples 1-7 in Table 1, it can be seen that the total number of fungi in the wheat flour prepared by the conventional wheat moistening method in Comparative Example 7 is far more than 10 3 cfu / g, while the total colony count of the wheat flour obtained in Examples 1-10 is below 380 cfu / g, and the content of mold and yeast is below 100 cfu / g; it shows that when the mixed solution of phage lytic enzyme, phenyllactic acid and water is combined with centrifugal filtration for wheat moistening, the phage lytic enzyme and phenyllactic acid synergistically act on the cell wall, cell membrane and nucleic acid of the microorganism during the standing process of the wheat and the mixed solution, inhibit the growth and reproduction of bacteria and mold in the wheat bran and wheat ventral groove, degrade fungal mycin, and reduce the content of microorganisms. Further, the microorganisms attached to the wheat epidermis can be effectively separated by centrifugation, and the wheat mixed solution is impacted during the centrifugation process, which destroys the integrity of the wheat cortex, shortens the route for water molecules to enter the endosperm, and shortens the moistening time. And as the centrifugal force (speed) increases during the centrifugation process, the degree of damage to the wheat cortex increases, and the moistening process is accelerated. The concentration of phage lytic enzyme and phenyllactic acid increases, and the bactericidal effect is enhanced, but after increasing to a certain concentration, the bactericidal effect no longer continues to change.

[0150] By comparing the results of Example 3 with those of Comparative Examples 1 and 7, it can be seen that centrifugal filtration can effectively reduce the microbial content in wheat flour, but its effect is limited. Wheat flour produced only by centrifugal filtration technology cannot meet the standard of low-bacteria wheat flour.

[0151] By comparing the results of Example 2 with those of Comparative Examples 5 and 6, it can be seen that the killing of wheat microorganisms by only using one means of bacteriophage lytic enzyme or phenyllactic acid in conjunction with centrifugation technology is far less effective than using the two substances in conjunction with centrifugation technology, and the use of phenyllactic acid has a greater impact on the fungal content.

[0152] Comparison of the results of Example 2 with Comparative Example 2 and Comparative Examples 5-6 shows that the microbial content of wheat flour produced by phage lytic enzyme and phenyllactic acid synergistically tempering wheat is significantly lower than that of conventional tempering wheat, but its bactericidal effect is worse than that of centrifugal filtration synergistically tempering a mixed solution of phage lytic enzyme and phenyllactic acid. Centrifugal filtration and the use of phage lytic enzyme and phenyllactic acid have a system synergistic effect.

[0153] It can be seen from Comparative Examples 3-4 that although ozone water moisturizing wheat and chlorine dioxide solution moisturizing wheat can effectively reduce the microbial content in wheat flour, their action time is short, stability is poor, and the comprehensive bactericidal effect is weaker than that of the present application.

[0154] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0155] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for preparing low-bacteria wheat flour, characterized in that: The steps include: preparing a mixed solution comprising bacteriophage lytic enzyme, phenyllactic acid and water; The mixed solution is mixed with wheat, and then allowed to stand and centrifuged and filtered; The wheat obtained after centrifugal filtration is sequentially tempered and floured.

2. The preparation method according to claim 1, characterized in that The mass ratio of the bacteriophage lytic enzyme, phenyllactic acid and water is (1-5):(50-200):10000.

3. The preparation method according to claim 1, characterized in that: The mass ratio of the mixed solution to the wheat is (0.5-2):

1.

4. The preparation method according to claim 1, characterized in that: The standing time is 5 min-60 min.

5. The preparation method according to claim 1, characterized in that: The centrifugal speed is 500rpm-20000rpm.

6. The preparation method according to claim 1, characterized in that: The centrifugation time is 1min-30min.

7. The preparation method according to claim 1, characterized in that: The temperature of the wheat tempering is 15°C-30°C.

8. The preparation method according to claim 1, characterized in that: The time for tempering the wheat is 4h-8h.

9. The preparation method according to any one of claims 1 to 8, characterized in that: The moisture content of the wheat obtained after centrifugal filtration is 15wt%-17wt%.

10. A low-bacteria wheat flour, characterized in that: The preparation is obtained by the preparation method according to any one of claims 1 to 9.

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