CN108175039B

CN108175039B - Superfine wall-broken crushed vegetable flour and preparation method thereof

Info

Publication number: CN108175039B
Application number: CN201810115175.5A
Authority: CN
Inventors: 任文明
Original assignee: Individual
Current assignee: LIANGCHENG COUNTY CENTURY GRAIN ROW CO.,LTD.
Priority date: 2018-02-06
Filing date: 2018-02-06
Publication date: 2022-01-04
Anticipated expiration: 2038-02-06
Also published as: CN108175039A

Abstract

The present invention provides a method for producing ultrafine wall-breaking and pulverizing vegetable flour and the vegetable flour obtained by the method, wherein the method comprises: subjecting vegetables to freeze-drying and dehydration treatment at a temperature of -55°C to -35°C, Make the moisture content of the vegetables after drying and dehydration ≤8% mass fraction; the vegetables after dehydration, ultra-finely broken and crushed the vegetable powder with a fineness of 270 mesh sieves, so that the average particle size of the vegetable particles is 53 μm; The flour is mixed and stirred evenly by three-dimensional double motion to obtain vegetable flour. The present invention solves the problems of unbalanced nutrition of vegetable flour in the prior art, unstable product quality (ineffective release of nutrients, pigments and flavor substances, uneven mixing), difficulty in large-scale standardized production, poor formability, serious decrease in taste, and easy Deterioration, short product shelf life, etc.

Description

Superfine wall-broken crushed vegetable flour and preparation method thereof

Technical Field

The invention relates to the field of food manufacturing, in particular to a method for manufacturing ultramicro wall-broken crushed vegetable flour and vegetable flour.

Background

The flour is used as staple food of people, has large demand, and can be divided into high gluten flour, medium gluten flour, low gluten flour and non-gluten flour according to the content of protein in the flour. Although the varieties of the flours supplied in the market are various, the flours have single nutrient and cannot meet the needs of human bodies, and the single flour cannot meet the increasing living demands of people along with the improvement of living standard and the enhancement of health care consciousness of people.

The vegetables can provide various nutrients such as vitamins and minerals necessary for human bodies, and are one of essential foods in daily diet of people. In China, most vegetables are generally ripe in spring or summer, and the vegetables in due seasons need to be refrigerated when the fresh vegetables are wanted to be eaten all the year round, and the vegetables can be rotten and deteriorated due to temperature difference in the refrigeration stage or unreasonable pretreatment before refrigeration. In addition, considering that some people do not like to eat vegetables, especially some children only like to eat meat, growth and development may be affected. Therefore, attempts have been made to add vegetables to flour to prepare vegetable flour that meets the demand for a healthy nutritional diet.

However, in the prior art, various vegetables are mainly squeezed into juice, because the fact that the whole vegetable ingredients are directly mixed into flour causes many technical difficulties, such as reduced flour formability and seriously influenced flour taste. However, the vegetable juice is added into the flour to prepare the vegetable flour, which has the defects of complex operation, poor mouthfeel, incomplete nutrient substances, unstable product quality, difficult storage and difficult mass standardized production. Especially, the lack of cellulose in vegetables results in that the flour containing only vegetable juice has the taste of vegetables, but cannot provide the functional effects of keeping intestinal health, promoting intestinal peristalsis and the like which the vegetables originally have.

The prior art CN107156642A discloses a nutritious noodle rich in green vegetables, which is prepared by adding vegetable powder into flour, but does not disclose a specific manufacturing method. The inventor of the invention operates according to the technical scheme that vegetables are crushed into fine powder and then mixed with flour, and finds that the fine vegetable powder has certain particle size, so that the flour has poor formability and seriously reduced mouthfeel. Further, since the above-mentioned technical means do not disclose a specific manufacturing method, those skilled in the art will be faced with many technical difficulties in practice.

The prior art CN1241364 discloses vegetable-containing flour and a manufacturing method thereof, and the method comprises the steps of cleaning vegetables, pulping, adding flour, stirring, drying, grinding, and then carrying out vacuum sealing packaging. The vegetable flour is prepared by drying at 25-45 deg.C, and because the vegetable pulp and flour are placed at 25-45 deg.C for a long time, a large amount of microorganisms are easy to breed, which causes flour deterioration and shortens the quality guarantee period of flour products.

Through intensive research, the inventor unexpectedly discovers a technical means for solving the technical problems of poor formability, seriously reduced mouthfeel, easy deterioration, short product shelf life and the like of flour added with vegetable powder. The technical problems which puzzle technicians in the field for many years in the prior art are comprehensively solved by comprehensively using the technical means of vegetable dehydration mode, grinding fineness, water content control, dry mixing and the like, and the prepared vegetable flour has the advantages of good taste, better formability and long shelf life.

Disclosure of Invention

In view of the above, the invention provides a vegetable flour manufacturing method and vegetable flour prepared by the method, so as to solve or alleviate one or more problems of unbalanced nutrition, unstable product quality (nutrition, pigment and flavor substances cannot be effectively released and are not uniformly mixed), difficulty in large-scale standardized production, poor formability, seriously reduced taste, easiness in deterioration, short product shelf life and the like of the vegetable flour in the prior art.

The invention provides a vegetable flour manufacturing method in a first aspect, which comprises the following steps: carrying out freeze drying and dehydration treatment on the vegetables at the temperature of-55 to-35 ℃ so that the water content of the dried and dehydrated vegetables is less than or equal to 8 mass percent; crushing the dehydrated vegetables into vegetable powder of 200-270 meshes so that the average particle size of the vegetables is 53-75 mu m; mixing and stirring vegetable powder and flour to obtain vegetable flour, wherein the mixing weight ratio of the vegetable powder is 2-6%, and the mixing weight ratio of the flour is 94-98%.

Alternatively, the dehydrated vegetables are pulverized into vegetable powder that can pass through 270 mesh so that the vegetable particle size is 53 μm on average.

Optionally, after the dehydrated vegetable is crushed into vegetable powder which can pass through a 270-mesh sieve so that the vegetable particle size is 53 μm on average, the method further comprises the following steps: and continuously carrying out freeze dehydration and drying on the crushed dehydrated vegetables to ensure that the water content of the powdery dehydrated vegetables reaches less than or equal to 6 mass percent.

Optionally, after the vegetable flour is obtained by mixing and stirring the vegetable powder and the flour, the method further comprises the following steps: the light transmittance is zero, and the gas barrier rate is less than 15cm³/m²·(24h)·1The vegetable flour is subjected to vacuum and sealed deoxidizer package by using a high-barrier packaging material of 01.325 kPa.

Optionally, before mixing and stirring the vegetable powder and the flour to obtain the vegetable flour, the method further comprises the following steps: making flour with fineness of 91-107 meshes and water content of less than 13%.

Optionally, the vegetable comprises at least one of: tuber vegetables, root vegetables or leaf vegetables.

Optionally, the flour comprises at least one of: wheat flour, oat flour or corn flour.

Optionally, the vegetable powder is mixed in an amount of 5% by weight and the flour is mixed in an amount of 95% by weight.

Optionally, the flour has a fineness of 100 mesh and a moisture content of < 10%.

In a second aspect, the present invention provides vegetable flour produced by the method for producing vegetable flour according to the first aspect.

In particular, the invention provides a vegetable flour manufacturing method which is used for manufacturing vegetable flour. Fig. 1 is a flow chart of a method of manufacturing vegetable flour according to an embodiment of the present invention. As shown in fig. 1, the process includes the following steps:

step S101, providing vegetables, and cleaning the vegetables to remove impurities. Specifically, fresh vegetables without insect pests, rottenness and deterioration are provided, roots and withered parts of leaves are removed, and silt and impurities on the surfaces of the vegetables are cleaned. In order to clean the vegetables more cleanly, in an optional embodiment, the vegetables are subjected to a cleaning process, namely a step of soaking the vegetables for 5-6 minutes at normal temperature by using edible alkali (the concentration is 2% -15%).

Also: the vegetable is blanched, namely hot water with the water temperature of 70-72 ℃ is adopted, edible salt is added to prepare light salt water with the concentration of 2%, and enzyme (peroxidase) deactivation and color protection treatment are carried out on the vegetable for 1-5 minutes.

Alternatively, the vegetables may be stem vegetables, root vegetables, fruit vegetables, leaf vegetables or fungus vegetables. In particular, it may be fruit and vegetable: tomato, pepper; root vegetables: carrot, radish, beet; green leaf vegetables: celery, spinach, wild vegetables and Chinese cabbage; fungus vegetables: mushroom, shiitake mushroom, oyster mushroom, straw mushroom, pholiota nameko, agaric, tremella and hericium erinaceus; algae dish: seaweed, kelp, and the like.

Step S102, the vegetables are subjected to freeze drying dehydration treatment at the temperature of-55 to-35 ℃ so that the water content of the dried and dehydrated vegetables is less than or equal to 8 percent (mass fraction). In order to speed up the freeze-drying dehydration process of the vegetables, in an alternative embodiment, the vegetables are sliced or diced before the freeze-drying dehydration process of the vegetables. In another alternative embodiment, the freeze-drying dehydration process may be specifically carried out by placing the sliced or diced vegetables in a vacuum freeze-dryer at a rate of 10 to 20kg/m²Spreading, and carrying out freeze drying dehydration treatment at the temperature of between 55 ℃ below zero and 35 ℃ below zero to ensure that the water content of the dried and dehydrated vegetables is less than or equal to 8 percent.

The vegetable is subjected to freeze drying and dehydration treatment at the temperature of between 55 ℃ below zero and 35 ℃ below zero, so that the tissue structure and the appearance form of the vegetable can be well preserved, the nutrient components in the vegetable can not be lost, the pigments such as active substances, chlorophyll, anthocyanin and the like in the vegetable can be well preserved, and the original nutrition, color and flavor of the vegetable can be furthest preserved.

Step S103, micronizing the dehydrated vegetables into vegetable powder of 200-270 meshes so that the average particle size of the vegetables is 53-75 μm. Preferably, in an alternative embodiment, the dehydrated vegetables are micronized into 270 mesh vegetable powder such that the vegetable particle size averages 53 μm. As the diameter of the plant cell is usually 10-100 μm, the wall breaking effect can be achieved through the step, and the digestion and absorption of the nutrient components by a human body are facilitated. The cell wall breaking technology is a technology for breaking the plant cell walls to enable moisture and nutrition to be absorbed by a human body better and keep active ingredients, releasing plant biochemical substances and fusing dietary fibers, vitamins and other nutrient elements to the maximum extent, so that the plant cell walls are easier to absorb by the human body. In an optional embodiment, the crushed dehydrated vegetables are continuously subjected to freeze dehydration and drying, so that the moisture content of the crushed dehydrated vegetables is less than or equal to 6 percent (mass fraction) to prolong the shelf life of the crushed dehydrated vegetables. According to one embodiment, the powdery dehydrated vegetables are isolated by the volume of 0.5 to 0.8 cubic meter, and then are subjected to freeze drying dehydration treatment at the temperature of-25 to-15 ℃ for 30 to 50 minutes. Experiments show that the taste can be kept well in the condition. This embodiment can reduce the burden on the cold room, and the time and effect are substantially the same as those in the case of lower temperature.

And step S104, mixing and stirring the ultramicro vegetable powder and flour to obtain vegetable flour. In an alternative embodiment, vegetable powder in a mixed weight ratio of 2% to 6% is proportioned and mixed with flour in a mixed weight ratio of 94% to 98%. In an alternative embodiment, the vegetable powder is mixed at a weight ratio of 5% and the flour is mixed at a weight ratio of 95%. The time for mixing can be properly set according to actual conditions, so that the vegetable powder and the flour are fully mixed, for example, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes, 60 minutes, 90 minutes, 120 minutes and the like. Those skilled in the art will appreciate that the mixing time can be flexibly adjusted, and any obvious time data variation is within the scope of the present embodiment.

The inventors have noticed that if the rotation speed is too high during mixing, the taste of the vegetable flour is deteriorated, which may be caused by the temperature increase of the material itself during the shearing, rubbing, penetration and convection of the vegetable powder and flour due to the too high rotation speed of the built-in helical blades. Too slow a speed of rotation would result in uneven mixing and efficiency. According to one embodiment, the mixing is carried out by rotating the built-in ribbon blades at a low speed in a first direction, then at a high speed, then stopping the rotation for 3min to 7min for cooling, then at a high speed, rotating the built-in ribbon blades in the opposite direction, and then at a low speed, wherein the high speed is 1/4 to 1/5 times the time of the low speed, the number of revolutions of the built-in ribbon blades at the high speed is 50r/min, and the number of revolutions of the low speed is 16 r/min. The barrel speed is preferably 1/2 which is the speed of the internal helical blades.

In order to improve the mouthfeel and prolong the shelf life of the vegetable flour, in an optional embodiment, the vegetable flour with fineness of 91-107 meshes and water content of less than 13% is prepared before the vegetable flour is obtained by mixing and stirring the vegetable flour and the flour. In an alternative embodiment, flour with a fineness of 100 mesh and a moisture content of 10% is produced. Alternatively, the flour may be wheat flour, oat flour or corn flour.

In an optional embodiment, after the step, the sensory, physicochemical and microbial indexes of the prepared vegetable flour can be detected, and the finished product is obtained after the detection is qualified.

By the vegetable flour manufacturing method comprising the steps, the problems that the vegetable flour in the prior art is unbalanced in nutrition, unstable in product quality (nutrition, pigments and flavor substances cannot be effectively released and are not uniformly mixed), difficult to produce in a large-scale standardized manner, poor in formability, seriously reduced in taste, easy to deteriorate, short in product shelf life and the like are solved, and the vegetable flour which is scientific and reasonable in nutrition proportion, pure in taste, easy to store, capable of being directly eaten and capable of realizing industrial production is prepared.

In order to prevent breeding of ova and oxidation fading in vegetable flour, a vacuum light-proof packaging process can be adopted, specifically, after vegetable flour and flour are mixed and stirred to obtain vegetable flour, the light transmittance can be zero, and the gas barrier rate is less than 15cm³/m²Vacuum packaging of vegetable flour is carried out by high-barrier packaging material of 101.325kPa (24 h). Further, a small deoxidizer package is added in the package to ensure that the package contains oxygen<0.5% (absolute pressure 1.33kPa) so that the shelf life can be as long as 12 months.

The preparation method of the vegetable flour solves the problems of unbalanced nutrition, unstable product quality and difficulty in large-scale standardized production of the vegetable flour in the prior art, thereby preparing the vegetable flour which has scientific and reasonable nutrition proportion, pure taste, easy storage, direct eating and industrial production.

Drawings

Fig. 1 is a flow chart of a manufacturing method of the ultrafine wall-broken pulverized vegetable flour according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described in detail and fully with reference to the accompanying drawings in the embodiments of the present invention.

Example 1

A method for preparing vegetable flour comprises the following steps:

step S101, providing vegetables, and cleaning the vegetables to remove impurities.

The vegetable is celery.

Step S102, the vegetables are subjected to freeze drying dehydration treatment at the temperature of-55 to-35 ℃ so that the water content of the dried and dehydrated vegetables is less than or equal to 8 percent (mass fraction).

Step S103, crushing the dehydrated vegetables into 270-mesh vegetable powder.

And step S104, mixing and stirring the vegetable powder and the flour to obtain vegetable flour. The method specifically comprises the steps of firstly rotating the mixed powder clockwise for 4 minutes at a low speed, rotating the mixed powder clockwise for 1 minute at a high speed, then stopping the rotation, after the mixed powder does not rotate any more, rotating the mixed powder anticlockwise for 1 minute at a high speed, then rotating the mixed powder anticlockwise for 4 minutes at a low speed, wherein the rotating speed of a charging barrel is 1/2 of the rotating speed of a built-in helical ribbon blade, and mixing the vegetable powder with the mixed weight ratio of 6% and the flour with the mixed weight ratio of 94% in a matching manner.

The flour is wheat flour.

And (3) detecting the sensory, physicochemical and microbial indexes of the prepared vegetable flour, and obtaining a finished product after the detection is qualified.

Example 2

A method for preparing vegetable flour comprises the following steps:

step S101, providing fresh vegetables without insect pests, rotting and deterioration, removing withered parts of roots and leaves, and cleaning silt and impurities on the surfaces of the vegetables.

The vegetable is a 1:1 mixture of tomato and shiitake mushroom.

And S102, before the vegetables are subjected to freeze drying dehydration treatment, slicing or dicing the vegetables, and then, carrying out freeze drying dehydration treatment on the vegetables at the temperature of-55 to-35 ℃ so that the water content of the dried and dehydrated vegetables is less than or equal to 8 percent (mass fraction).

And step S103, crushing the dehydrated vegetables into vegetable powder capable of passing through a 270-mesh sieve so that the average particle size of the vegetables is 53 microns.

And step S104, mixing and stirring the vegetable powder and the flour to obtain vegetable flour. The method specifically comprises the steps of firstly rotating clockwise for 5 minutes at a low speed, rotating clockwise for 1 minute at a high speed, then stopping, after the mixed powder does not rotate any more, rotating anticlockwise for 1 minute at a high speed, then rotating anticlockwise for 5 minutes at a low speed, wherein the rotating speed of a charging barrel is 1/2 of the rotating speed of a built-in helical ribbon blade, and proportionally mixing vegetable powder with the mixed weight ratio of 4% and flour with the mixed weight ratio of 96%.

The flour is oat flour.

After the vegetable flour is obtained by mixing and stirring the vegetable powder and the flour, the vegetable flour with light transmittance of zero and gas barrier rate of less than 15cm can be used³/m²High-barrier packaging material (24h) 101.325 kPa), vacuum-sealing the vegetable flour and packaging with deoxidizer.

Example 3

A method for preparing vegetable flour comprises the following steps:

step S101, providing fresh vegetables without insect pests, rotting and deterioration, removing withered parts of roots and leaves, and cleaning silt and impurities on the surfaces of the vegetables. After washing vegetables, the vegetables were soaked in 5% saline for 30 minutes.

The above vegetables are 1 of tomato, carrot, spinach, agaric and seaweed: 1: 1: 1: 1.

Step S102, before the vegetable is subjected to freeze drying dehydration treatment, the vegetable is subjected to slicing or dicing treatmentThen placing the sliced or diced vegetable in a vacuum freeze-dryer at a ratio of 10 to 20kg/m²Spreading, and performing freeze drying and dehydration treatment at the temperature of-55 to-35 ℃ to ensure that the water content of the dried and dehydrated vegetables is less than or equal to 8 percent (mass fraction).

And step S103, crushing the dehydrated vegetables into vegetable powder which can pass through a 270-mesh sieve, so that the average particle size of the vegetables is 53 microns. And continuously carrying out freeze dehydration and drying on the crushed dehydrated vegetables to ensure that the water content of the powdery dehydrated vegetables is less than or equal to 6 percent (mass fraction).

And step S104, mixing and stirring the vegetable powder and the flour to obtain vegetable flour. The method specifically comprises the steps of firstly rotating the mixed powder clockwise for 8 minutes at a low speed, rotating the mixed powder clockwise for 2 minutes at a high speed, then stopping the rotation, after the mixed powder does not rotate any more, rotating the mixed powder anticlockwise for 2 minutes at a high speed, then rotating the mixed powder anticlockwise for 8 minutes at a low speed, wherein the rotating speed of a charging barrel is 1/2 of the rotating speed of a built-in helical ribbon blade, and mixing the vegetable powder with the mixed weight ratio of 2% and the flour with the mixed weight ratio of 98%, wherein the fineness of the flour is 107 meshes and the water content is 10%.

The flour is wheat flour.

After the vegetable flour is obtained by mixing and stirring the vegetable powder and the flour, the vegetable flour with light transmittance of zero and gas barrier rate of less than 15cm can be used³/m²Vacuum packaging vegetable flour with high-barrier packaging material of (24h) 101.325kPa, and packaging with small deoxidizer bag to make the package contain oxygen<0.5% (absolute pressure 1.33 kPa).

Example 4:

a method for preparing vegetable flour comprises the following steps:

step S101, providing fresh vegetables without insect pests, rotting and deterioration, removing withered parts of roots and leaves, and cleaning silt and impurities on the surfaces of the vegetables. After washing vegetables, the vegetables were soaked in 5% saline for 3 hours.

The above vegetables are Chinese cabbage and herba Zosterae Marinae 1: 1.

Step S102, before the vegetables are subjected to freeze drying dehydration treatment, the vegetables are subjected to slicing or dicing treatment, and then the sliced or diced vegetables are placed in a vacuum freeze dryer according to the ratio of 10-20 kg/m²Spreading, and performing freeze drying dehydration treatment at the temperature of-55 to-35 ℃ to ensure that the water content of the dried and dehydrated vegetables is less than or equal to 8 percent (mass fraction).

And step S103, crushing the dehydrated vegetables into vegetable powder capable of passing through a 270-mesh sieve so that the average particle size of the vegetables is 53 microns. And continuously carrying out freeze dehydration and drying on the crushed dehydrated vegetables to ensure that the water content of the powdery dehydrated vegetables is less than or equal to 6 percent (mass fraction).

And step S104, mixing and stirring the vegetable powder and the flour to obtain vegetable flour. The method specifically comprises the steps of firstly rotating the vegetable powder at a low speed for 4 minutes in a counterclockwise manner, rotating the vegetable powder at a high speed for 1 minute in a counterclockwise manner, then stopping the rotation, after the mixed powder does not rotate any more, rotating the vegetable powder at a high speed for 1 minute in a clockwise manner, then rotating the vegetable powder at a low speed for 4 minutes in a clockwise manner, wherein the rotating speed of a charging barrel is 1/2 of the rotating speed of a built-in helical blade, and mixing the vegetable powder with the mixed weight ratio of 5% and the flour with the mixed weight ratio of 95%, wherein the fineness of the flour is 91-107 meshes, and the water content is less than 13%.

The flour is a 1:1 mixture of corn flour and wheat flour.

Test example:

the following representative test examples are provided to better explain the unexpected technical effects of the present invention, but the experimental studies actually performed by the inventors of the present invention are not limited to the following test examples.

Test example 1: flour (moldability and taste) made from vegetable powder with different fineness of pulverization

The experiment is to study the influence of the vegetable powder grinding fineness on the quality of the finished flour by investigating the formability and mouthfeel of vegetable flour prepared from vegetable powder with different grinding fineness.

Test subjects: the test group was vegetable flour (average particle size 75um) obtained according to the protocol of example 4. Comparative example 1 group (i.e., vegetables were pulverized into fine powder having an average particle size of 45 μm (325 mesh) in step S103, and the rest was the same as in example 4), comparative example 2 group (i.e., vegetables were pulverized into fine powder having an average particle size of 106 μm (150 mesh) in step S103, and the rest was the same as in example 4), comparative example 3 group (i.e., vegetables were pulverized into fine powder having an average particle size of 212 μm (70 mesh) in step S103, and the rest was the same as in example 4), and comparative example 4 group (i.e., vegetables were pulverized into fine powder having an average particle size of 425 μm (35 mesh) in step S103, and the rest was the same as in example 4).

The test process comprises the following steps: the above groups of test subjects were processed into cylindrical dry noodles having a length of 20cm and a diameter of 2mm according to the same noodle processing method which is conventional in the art, and then measured for moldability and mouthfeel. The moldability was measured by placing 5L of water in a 10L vessel and boiling, placing 100 dried noodles of the same length, followed by stirring with a 10 rpm paddle for 10 minutes. Subsequently, the number of noodle strings without breakage was measured to evaluate moldability, and the same experiment was repeated 10 times with the average value as the result of moldability evaluation. The taste was measured by cooking the five groups of products into noodles in the same manner, then tasting 10 volunteers, each volunteer tasted 5 kinds of noodles simultaneously, and given a score of 1-10 points according to the taste, wherein 10 points are very good taste, and 1 point is very poor taste. Statistical analysis was then performed to calculate the average score for each group.

And (3) test results:

group of	Formability	Taste of the product
			Test group	96.4	9.5
Comparative example 1 group	91.8	9.0
			Comparative example 2 group	80.4	7.2
Comparative example 3 group	72.7	6.7
			Comparative example 4 group	55.7	3.1

The results showed that the flour made of the vegetable fine powder having an average particle size of 53 μm or less after pulverization had better moldability and mouthfeel, and that the flour made of the vegetable fine powder having an average particle size of 106 μm or more after pulverization had relatively poor moldability and mouthfeel. Further, as a result of the above studies, the present inventors have unexpectedly found that it is not preferable that the fineness of the vegetable fine powder is as fine as possible and that the optimum average particle diameter is 53 μm. Of course, the evaluation of the fine powder with a particle size of 45 μm (i.e., when the fine powder can pass through a sieve of 325 mesh or more) can also be carried out well to achieve the technical effects in the art.

Test example 2: flour (taste) made from vegetable powder with different dehydration methods

The experiment is to study the influence of the vegetable powder dehydration mode on the quality of the finished flour product by investigating the mouthfeel of the vegetable flour prepared from the vegetable powder obtained by different dehydration methods.

Test subjects: the experimental group was vegetable flour (freeze-dried and dehydrated) obtained according to the technical scheme of example 2. Comparative example 1 (heat drying group, step S102, before freeze drying dehydration treatment of vegetables, the vegetables were sliced or diced, then the vegetables were dried and dehydrated in a hot air circulation oven at a temperature of 50 ℃ so that the moisture content of the dried and dehydrated vegetables was 8% (mass fraction) or less, the remaining steps were the same as in example 2), comparative example 2 (dry drying group, step S102, before freeze drying dehydration treatment of vegetables, the vegetables were sliced or diced, then the vegetables were dried and dehydrated at a low temperature in a drying air chamber at a temperature of 15 ℃ so that the moisture content of the dried and dehydrated vegetables was 8% (mass fraction) or less, and the remaining steps were the same as in example 2).

The test process comprises the following steps: the above groups of test subjects were processed into cylindrical dry noodles having a length of 20cm and a diameter of 2mm according to the same noodle processing method which is conventional in the art, and then the mouth feel was measured. The taste was measured by cooking the three groups of products into noodles in the same manner, then tasting the noodles by 10 volunteers, each volunteer tasted 3 kinds of noodles simultaneously, and given a score of 1-10 points according to the taste, wherein 10 points are very good taste, and 1 point is very poor taste. Statistical analysis was then performed to calculate the average score for each group.

And (3) test results:

group of	Taste of the product
		Test group	9.3
Comparative example 1 group	8.9
		Comparative example 2 group	9.0

As the skilled person knows, freeze-drying can better retain the nutritional components in vegetables in general, and the temperature-sensitive components such as vitamins are not damaged, and the vitamin C content determination tests performed by the applicant on three vegetable components such as freeze-drying, heat drying and drying in the shade also confirm the above-mentioned point. Meanwhile, aiming at the fact whether the three different drying modes affect the taste of the finished flour, corresponding technical inspiration is not provided in the prior art, and through the experiment, the fact that the freeze-dried vegetables can enable the product to have better taste, color and fragrance is found, and an unexpected technical effect is achieved.

Test example 3: influence of flours of different moisture contents on the quality of the product (shelf life)

The test is to study the influence of the water content of the flour used on the quality of the finished flour by investigating the shelf life of vegetable flour prepared from flours with different water contents.

Test subjects: the test group was vegetable flour obtained according to the technical scheme of example 3 (the flour in step S104 was 107 mesh flour, and the corn flour had a water content of 10%). Comparative example 1 group (the flour in step S104 was 200 mesh corn flour with 5% moisture, the rest of example 3). Comparative example 2 group (flour in step S104 was 120 mesh, corn flour with 7% moisture content, the rest of example 3). Comparative example 3 group (the flour in step S104 was 80 mesh, corn flour with 13% moisture content, the rest of example 3). Comparative example 4 group (the flour in step S104 was 50 mesh, corn flour with 15% moisture content, the rest of example 3).

The test process comprises the following steps: and (3) placing the finished vegetable flour products obtained by the tests at the temperature of 60 ℃ for 3 months, and carrying out a stability acceleration test. And (3) taking out the product after 3 months, and respectively carrying out color and smell tests, (1) placing the sample under the radiation light, and visually checking whether the color and the luster of all the samples are normal. (2) And (4) odor identification, namely, taking a small amount of sample, and immediately smelling whether the odor is normal or not when the sample takes care of the odor. Secondly, the sample is put into a closed vessel, is kept warm for several minutes in warm water at the temperature of 60-70 ℃, and is taken out to immediately smell and distinguish whether the smell is normal or not. And thirdly, the results are expressed as normal and abnormal, and the normal vegetable flour has inherent color, luster and smell, so that abnormal results are explained. The normal smell is the due fresh smell and storage smell of the product; the harmful odor is damp mildew odor, acidic odor, and miscellaneous odor.

And (3) test results:

group of	Color	Smell(s)
			Test group	The color and luster are not changed	Is normal
Comparative example 1 group	Dark color and luster and agglomeration	Is normal
			Comparative example 2 group	The color and luster are not changed	Normal, but slightly storage smell
Comparative example 3 group	Slightly darker color and luster	Is normal
			Comparative example 4 group	Blackened color and luster	Abnormal, damp and musty smell

The result shows that when the flour fineness is 80-120 meshes and the humidity is 7-13%, the prepared vegetable flour finished product has better stability and longer shelf life. The experiment unexpectedly finds that when the flour fineness is 107 meshes and the humidity is 10%, the stability of the product is the best, and the shelf life is the longest. When the fineness of the flour is 200 meshes, the vegetable flour finished product is easy to agglomerate, and the quality guarantee period is shortened. Similarly, when the humidity is 15%, the finished vegetable flour product is easy to mildew and has short shelf life.

And then taking new test objects with flour fineness of 80-120 meshes and humidity of 7-13%, namely finished vegetable flour products of the experimental group, the comparative group 2 and the comparative group 3, placing for 2 years at room temperature and normal humidity, and inspecting the quality of the products, wherein the shelf life of the test objects can be found to be more than 2 years.

Test example 4: different mixing modes (drying after mixing compared with dry mixing) (shelf life)

This test was conducted to investigate the effect of different mixing regimes on the quality of the finished flour by investigating the shelf life of vegetable flour made by different regimes of mixing flour and vegetables together.

Test subjects: the test group was vegetable flour obtained according to the technical scheme of example 1 (i.e. vegetables were made into dry powder and then dry-mixed with flour). Comparative example 1 (i.e., a method of wet-mixing and drying vegetables after beating, wherein before the vegetables are crushed and beaten, the vegetables are sliced or diced, then the vegetables are crushed and beaten into vegetable suspension capable of passing through a 270 mesh sieve so that the average particle size of the vegetables is 53 μm. the vegetable slurry is wet-mixed with flour to obtain a mixture, specifically, the vegetable slurry (corresponding to dry vegetable powder having a water content of 8% and a mixing weight ratio of 4%) is mixed with flour having a mixing weight ratio of 96%, the mixture is freeze-dried and dehydrated at a temperature of-55 ℃ to-35 ℃ to obtain vegetable flour, and the remaining steps are the same as in example 1).

The test process comprises the following steps: and (3) placing the finished vegetable flour products obtained in the two groups of tests at the temperature of 60 ℃ for 3 months, and carrying out a stability acceleration test. And (3) taking out the product after 3 months, and respectively carrying out color and smell tests, (1) placing the sample under the radiation light, and visually checking whether the color and the luster of all the samples are normal. (2) And (4) odor identification, namely, taking a small amount of sample, and immediately smelling whether the odor is normal or not when the sample takes care of the odor. Secondly, placing the sample into a closed vessel, preserving the temperature for several minutes in warm water at the temperature of 60-70 ℃, and immediately smelling to determine whether the smell is normal or not after taking out. And thirdly, the results are expressed as normal and abnormal, and the normal vegetable flour has inherent color, luster and smell, so that abnormal results are explained. The normal smell is the due fresh smell and storage smell of the product; the harmful odor is damp mildew odor, acidic odor, and miscellaneous odor.

And (3) test results:

group of	Color	Smell(s)
			Test group	The color and luster are not changed	Is normal
Comparative example 1 group	Color and luster become dark	Abnormal and slightly acidic odor

The results show that the mixing mode of making the vegetables into dry powder and then mixing the vegetables with the flour by a dry method can have longer shelf life. The method of pulping the vegetables, mixing the pulped vegetables with flour in a wet manner and then drying the vegetables has short shelf life. The technical effect achieved by the different mixing modes is never disclosed in the prior art and is unexpected.

Example 5: comparison of Secondary dehydration (shelf life)

The test is to investigate the influence of the secondary freeze-drying on the quality of the finished flour by investigating whether the quality guarantee period of the vegetable flour prepared by the secondary freeze-drying of the crushed vegetable powder is long.

Test subjects: the test group was vegetable flour obtained according to the technical scheme of example 3 (i.e. the vegetable powder obtained after grinding was freeze-dried twice). Comparative example 1 group (i.e., vegetable powder was not subjected to secondary freeze-drying. step S103 was to crush the dehydrated vegetables into vegetable powder of more than 270 mesh so that the vegetable particle size was 53 μm on average. the rest of the steps were the same as in example 3).

And (3) test results:

group of	Color	Smell(s)
			Test group	The color and luster are not changed	Is normal
Comparative example 1 group	The color and luster are not changed	Abnormal, slightly damp and musty smell

The results show that the vegetable powder can be subjected to secondary dehydration and drying, and has longer shelf life. And if the vegetable powder is not dehydrated and dried for the second time, the shelf life is shorter.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A manufacturing method of ultramicro wall-broken crushed vegetable flour is characterized by comprising the following steps:

carrying out freeze drying and dehydration treatment on the vegetables at the temperature of-55 to-35 ℃ so that the water content of the dried and dehydrated vegetables is less than or equal to 8 mass percent;

crushing the dehydrated vegetables into vegetable powder with the fineness of 270 meshes or 325 meshes to ensure that the average particle size of the vegetable particles is 53 mu m or 45 mu m;

mixing vegetable powder and flour, stirring to obtain vegetable flour, wherein the mixing weight ratio of the vegetable powder is 2-6%, the mixing weight ratio of the flour is 94-98%,

in the step of mixing and stirring the vegetable powder and the flour to obtain the vegetable flour, a three-dimensional double-motion mixing and stirring method is adopted to ensure that the CV (coefficient of variation) of the mixing uniformity is less than or equal to 5 percent, the working process comprises the steps of rotating and mixing the built-in spiral-ribbon blades at low speed along a first direction except the rotation of a charging barrel, then rotating and mixing the built-in spiral-ribbon blades at high speed, then stopping 3min for cooling, then rotating and mixing the built-in spiral-ribbon blades at high speed along the opposite direction, and then mixing the mixed materials in a low-speed rotating and mixing mode, wherein the high-speed rotating and mixing time is 1/4-1/5 of the low-speed rotating and mixing time, the high-speed rotating speed of the built-in spiral-ribbon blades is 50r/min, the low-speed rotating is 16r/min, and the rotating speed of the charging barrel is 1/2 of the rotating speed of the built-in spiral-ribbon blades.

2. The vegetable flour production method as claimed in claim 1, further comprising, after the vegetable particles are made to have an average particle diameter of 53 μm or 45 μm:

and continuously carrying out freeze dehydration and drying on the crushed dehydrated vegetables to ensure that the water content of the powdery dehydrated vegetables reaches less than or equal to 6 mass percent.

3. The method of producing vegetable flour as claimed in claim 2, wherein the step of continuing freeze-dehydration drying of the dehydrated vegetable after pulverization comprises:

the powdery dehydrated vegetables are measured in a volume of 0.5-0.8 cubic meter;

and (3) continuously carrying out vacuum freeze drying and dehydration treatment on the vegetables at the temperature of between 25 ℃ below zero and 15 ℃ below zero for 30 to 50 minutes, and then carrying out moisture-proof packaging for later use.

4. The method for producing vegetable flour as claimed in claim 1, wherein the flour has a fineness of 91-107 meshes and a moisture content of < 13%.

5. A vegetable flour production method according to any one of claims 1 to 4 wherein the vegetable comprises at least one of: the flour comprises stem vegetables, root vegetables, fruit vegetables, leaf vegetables or fungus vegetables, and at least one of the following materials: wheat flour, oat flour, buckwheat flour, or corn flour.

6. The method for producing vegetable flour according to any one of claims 1 to 4, wherein the step of subjecting the vegetable to vacuum freeze-drying dehydration at a temperature of-55 ℃ to-35 ℃ is preceded by:

a step of cleaning vegetables, namely soaking the vegetables for 5-6 minutes at normal temperature by using edible alkali with the concentration of 2% -15%; and

blanching vegetables, namely adopting hot water with the water temperature of 70-72 ℃, adding edible salt to prepare light salt water with the concentration of 2%, and carrying out enzyme deactivation and color protection treatment on the vegetables for 1-5 min.

7. The vegetable flour manufacturing method as claimed in any one of claims 1 to 4, wherein the vegetable powder is mixed in a weight ratio of 5%, the flour is mixed in a weight ratio of 95%, the flour has a fineness of 107 mesh, a moisture content of 10%, and a vegetable particle size of 53 μm on average.

8. The method for producing vegetable flour as claimed in claim 1, wherein after mixing vegetable powder with flour to obtain vegetable flour, further comprising:

the light transmittance is zero and the gas barrier rate is less than 15cm³/m²High-barrier packaging material (24h) 101.325 kPa), and the vegetable flour is subjected to vacuum and sealed deoxidizer packaging, wherein the vacuum degree is 0.600-1.333 kPa.

9. Vegetable flour, characterized in that it is produced by a method for producing vegetable flour according to any one of claims 1-8.