CN115633760A

CN115633760A - Grain processing method

Info

Publication number: CN115633760A
Application number: CN202211330038.6A
Authority: CN
Inventors: 聂润清
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-10-27
Filing date: 2022-10-27
Publication date: 2023-01-24

Abstract

The invention relates to a grain processing method, which belongs to the technical field of grain processing and comprises the following steps: picking the grains off when the grains enter the final stage of grouting, and draining water after cleaning; then baking, wherein the baking comprises a high-temperature fast baking stage and a low-temperature slow baking stage; and (3) performing low-temperature cooling and low-temperature air drying on the baked grains, and then threshing, and completing the processing through multiple processes. The invention overturns the traditional processing mode, cuts off the grains which reach the peak value in the final stage of grouting for processing, does not damage any part of the grains, keeps the substances such as anthocyanin and the like in the grains on one hand, keeps the structures such as inner membranes, germs and the like of the grains on the other hand, and ensures the comprehensive nutrition of processed food.

Description

Grain processing method

Technical Field

The invention relates to the technical field of grain processing, in particular to a grain processing method.

Background

The ' five cereals are used as nutrients ' in the Huangdi's Canon of medicine, and the ' Chinese resident dietary guidelines ' also indicate ' food diversity, cereals are main foods ', namely the main foods commonly known by people, such as rice, millet, corn, sorghum and the like. From its nutritional contribution, grains provide the human with a major energy source and a large majority of nutrients, such as carbohydrates, proteins, dietary fibers, and B-vitamins. In order to ensure the taste and facilitate the digestion and absorption of human bodies, the grains must be processed before being eaten. Generally, cereal grains are subjected to procedures such as husking, grinding, screening and the like, parts such as hulls, skin layers, embryos and the like are removed, endosperm is mainly reserved, and various nutritional ingredients of the grains are transferred into byproducts and lost due to different distribution of the nutritional ingredients. Therefore, grain processing needs to be a method, on one hand, certain processing precision is required to ensure the edible quality of finished products, and on the other hand, the loss of nutrient components is required to be reduced as much as possible.

The current common processing method is grain milling, namely, raw grains are subjected to crust removal and skin and embryo removal to obtain purer whole grain or coarse grain endosperm and grains which are packaged into grains, and the grain milling comprises two modes of dry processing and wet processing. The dry processing comprises crushing raw grain, peeling endosperm coarse grains from cortex, grinding into powder such as wheat flour, rye flour, and corn flour, or pulverizing some grain products directly and sieving to obtain powder such as rice flour and sorghum rice flour. The wet processing comprises soaking raw grain or granular finished grain, absorbing water, softening, grinding to extract slurry endosperm, purifying, and drying to obtain powder, such as water-milled rice flour, corn starch, wheat starch, etc. However, regardless of dry processing or wet processing, excessive finishing can improve the taste of grains so that the grains are not rough and are beneficial to digestion and absorption, but the processing mode can cause the grains to lose a large amount of nutrient substances. In the case of wheat, the higher the processing accuracy at the time of milling, the greater the loss of nutrients. For example, the protein content in the refined white powder is 27 percent lower than that of the standard powder, the fat content is 23 percent lower than that of the standard powder, the vitamin B1 content is 87 percent lower than that of the standard powder, the nicotinic acid content is 56 percent lower than that of the standard powder, and the contents of other trace elements such as calcium, phosphorus and iron are also greatly reduced.

The nutrition preservation, the appearance quality and the palatability are three problems which are difficult to solve and contradictory in the grain processing technology all the time. Taking rice as an example, the rice processing is to make the rice into rice, and comprises two procedures of hulling and rice milling. Husking is to peel off the inner and outer shells and glume protection of rice, husking is to grind off the cortex and embryo on brown rice, and the remaining endosperm is rice. Because the vitamins of the rice are mainly concentrated in the cortex, aleurone layer and embryo of the brown rice, the aleurone layer contains more protein and fat, most of the vitamins, protein and fat are transferred into rice bran along with the milled aleurone layer along with the removal of the cortex, aleurone layer and embryo during rice milling, and the loss is usually about 20%. However, the brown rice has poor appearance and palatability and a low market prospect, although it can ensure comprehensive nutrition as much as possible. Therefore, there is still a need to find a method of processing cereals that balances nutrition, appearance and taste.

Disclosure of Invention

In order to solve the technical problems, the invention provides the grain processing method, and the grains processed by the method have the advantages of comprehensive nutrition reservation, crystal clear appearance, good taste, easy digestion and the like.

The invention aims to provide a grain processing method, which comprises the following steps:

s1, picking the grains off at the end of a grain grouting period, and draining water after cleaning;

s2, baking the washed grains; the baking comprises two stages: the first stage is a high-temperature fast baking stage, the second stage is a low-temperature slow baking stage, specifically, baking at 270-280 deg.C for 3-5min, and baking at 150-160 deg.C for 10-20min;

s3, cooling the baked grains at low temperature;

s4, air-drying the cooled grains at a low temperature;

s5, threshing the air-dried grains, and then removing dust from the obtained grains;

s6, removing the outer skin of the obtained grains and performing secondary dust removal;

and S7, refrigerating and storing the obtained product.

The growth and development process of a plant can be divided into three stages, namely, vegetative growth stage (from seed germination to tillering), vegetative growth and reproductive growth merging stage (from jointing to booting), and reproductive growth stage (from heading to ripening). In the third growth stage, the grain is formed and then enters the grain filling stage, which is a fixed growth stage of the crop, also called the milk stage, and is a stage in which the starch, protein and accumulated organic matter produced by photosynthesis are stored in the grain through assimilation. Except for special description, the grouting period in the invention refers to the stage, the picking-off time is the peak period after the final grouting period, taking northeast different rice varieties as examples, the optimal picking period is slightly different: for example, the maturation period of Donggao 121 is about 135 days, and the optimal processing period is 124-126 days; the mature period of the nine-rice 80 is about 136 days, and the optimal processing period is 125-127 days; the mature period of the Tong system 937 is about 137 days, and the optimal processing time period is 126-128 days; the mature periods of the Tonghe 868 and the Donggao 275 are both about 138 days, and the optimal processing period is 127-129 days.

Further, in step S1, the moisture content of the grain is 25% -35%.

Further, in step S3, low-temperature cooling is performed at-5 to 5 ℃.

Further, in step S3, the temperature is cooled for 10-20min.

Further, in step S4, low-temperature air drying is performed at 5 to 10 ℃.

Further, in step S4, the air is dried for 48-72h at low temperature.

Further, the water content of the grains air-dried in the step S4 is 14% -15%.

Grain seeds and glumes in the period from the filling period to the mature period are tightly connected and are not easy to separate, the grains after two-section type baking are quickly cooled and threshed after low-temperature air drying, and the grains immediately enter low temperature compared with the grains with hulls baked at overheat temperature, so that rice in the grains and an outer coating film of the rice are quickly contracted and separated from the adhered shells, and the perfect forming of the rice in the shells is accelerated after low-temperature air drying, so that the threshing rate is greatly improved. Meanwhile, the low-temperature air drying also has the functions of reserving the nutrient substances of the grains and enhancing the mouthfeel.

Further, in step S5 or S6, the dust removal is anhydrous dust removal. The primary dust removal in the step S5 is to ensure the cleanness of the grains, and the secondary dust removal in the step S6 cannot be contacted with water, so that the product obtained by the invention can rapidly expand when meeting water, and the expansion can cause the outer envelope of the rice to fall off, thereby causing the loss of nutrient substances.

Further, in step S7, screening, grading, vacuum packaging, and the like are further included before the refrigerated storage. In order to keep the appearance and nutrition of the product from losing, the product prepared by the invention needs to be refrigerated, taking rice as an example, the product prepared by the invention is emerald green or dark green (which is milk white in rice when being picked), and if the product is not refrigerated for storage, the product gradually turns yellow at normal temperature, the nutrition is lost, and the taste is also reduced.

Further, the grains include, but are not limited to, rice, wheat, corn, millet, sorghum, black rice, red rice, barley, oat, buckwheat, glutinous rice, scented rice, and the like.

Further, when the grain is rice, wheat, red rice, barley, oat, buckwheat, glutinous rice, scented rice, etc., the processed product is emerald green or dark green.

By means of the scheme, the invention at least has the following advantages:

the invention overturns the traditional processing mode, cuts off grains which reach the peak value at the final stage of grouting for processing without damaging any part of the grains, on one hand, reserves substances such as anthocyanin and the like in the grains, can be used for enhancing the immune system function of an organism, fully exerts the functions of antioxidation, inflammation inhibition, allergy protection and the like, on the other hand, reserves the structures of tunica intima, germ and the like of the grains, and ensures the comprehensive nutrition of a processed product.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to make the technical solutions of the present invention practical in accordance with the contents of the specification, the following description is made with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

In order that the present invention may be more readily and clearly understood, there now follows a more particular description of the invention, reference being had to the accompanying drawings in which specific embodiments thereof are shown.

FIG. 1 is a schematic representation of the product obtained after processing in example 1.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Example 1

Oryza sativa 121 with a growth maturity of 135 days was selected and processed as follows when the final stage of the growth filling reached the peak (day 125):

(1) Cutting off rice ears, cleaning with clear water, draining off water, and controlling the water content to be 25% -35%;

(2) Feeding the rice ears into an oven for baking, setting the oven temperature at 270 ℃ for 5min, and immediately transferring into the oven with the oven temperature of 160 ℃ for baking for 10min;

(3) After baking, placing the rice ears in a low-temperature chamber at 0 ℃ for rapid cooling for 15min;

(4) Then air-drying in an air-drying chamber at 5-10 ℃ for 60h;

(5) After being dried, the rice is threshed by a single-spike thresher;

(6) Dedusting;

(7) Entering a machine to remove the shell, and removing dust again after the shell is removed;

(8) Screening, bagging according to grades, vacuum sealing, covering with outer protective film, sealing again, and refrigerating in a refrigerator.

FIG. 1 shows that the rice product obtained by the preparation method is emerald green, transparent in color and full in grain.

Example 2

Selecting a general system 937 with the growth mature period of 137 days, and processing the following steps when the final stage of the growth grouting reaches a peak value (127 th day):

(1) Cutting off the rice ears, cleaning the rice ears by using clear water, draining the water, and controlling the water content to be 25-35%;

(2) Feeding the rice ears into an oven for baking, setting the oven temperature to be 280 ℃ for 3min, and then immediately transferring into the oven with the oven temperature of 150 ℃ for baking for 15min;

(3) After baking, quickly putting the rice ears into a low-temperature chamber with the temperature of-3 ℃ for quickly cooling for 10min;

(4) After the temperature is reduced, entering a low-temperature air drying stage, and carrying out air drying at 10 ℃ for 48h;

(5) Sending the air-dried rice ears into a single ear threshing machine for threshing;

(6) Dedusting;

(8) Screening, bagging according to grades, vacuum sealing, covering with an outer protective film, sealing again, and refrigerating in a refrigerator.

Comparative example 1

Oryza sativa 121 with a growth maturity of 135 days was selected, picked up on day 131 and processed in the same manner as in example 1.

Comparative example 2

(2) Baking the rice ears in an oven at 270 ℃ for 10min;

(3) After the baking is finished, placing the rice ears in a low-temperature chamber for rapid cooling at 0 ℃ for 15min;

(4) Then air-drying in an air-drying chamber at 5-10 ℃ for 60h;

(5) After being dried, the rice is threshed by a single-spike thresher;

(6) Dedusting;

Comparative example 3

(2) Feeding the rice ears into an oven for baking, setting the oven temperature to be 270 ℃ for 3min, and then immediately transferring into the oven with the oven temperature of 160 ℃ for baking for 15min;

(4) Then air-drying at 25-30 ℃ for 60h;

(5) After being dried by the air, the rice is threshed by a single ear thresher;

(6) Removing dust;

(7) Entering a machine to remove the shell, and removing dust again after removing the shell;

Test example

(1) The threshing effect of example 1 and comparative example 3 were compared, and the results were as follows:

TABLE 1 results of clean removal

	Net removal rate (%)
		Example 1	81.2-85.7
Comparative example 3	42.6-50.4

(2) The Dong rice 121 processed in example 1 was compared with a commercially available Dong rice 121 in terms of nutritional value, and the test results are as follows.

TABLE 2 nutritional value test results

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the spirit or scope of the invention.

Claims

1. A method of processing grain, comprising the steps of:

s2, baking the washed grains; the baking is carried out at 270-280 ℃ for 3-5min, and then the baking is carried out at 150-160 ℃ for 10-20min;

s3, cooling the baked grains at low temperature;

s4, air-drying the cooled grains at a low temperature;

s5, threshing the air-dried grains, and then removing dust;

s6, removing the outer skin of the grains, and then performing secondary dust removal;

and S7, refrigerating and storing the obtained product.

2. The grain processing method according to claim 1, wherein: in step S1, the moisture content of the grain is 25% -35%.

3. The grain processing method according to claim 1, wherein: in step S3, low temperature cooling is performed at-5 to 5 ℃.

4. The grain processing method according to claim 1, wherein: in step S3, the temperature is cooled for 10-20min.

5. The grain processing method according to claim 1, wherein: in step S4, low-temperature air drying is carried out at 5-10 ℃, and the air drying time is 48-72h.

6. The grain processing method according to claim 1, wherein: and the water content of the grains air-dried in the step S4 is 14-15%.

7. The grain processing method according to claim 1, wherein: in step S5 or S6, the dust removal is anhydrous dust removal.

8. The method of claim 1, wherein: the cereals include one or more of rice, wheat, corn, millet, sorghum, glutinous rice, scented rice, black rice, red rice, barley, oat, and buckwheat.

9. The processing method according to claim 1, characterized in that: the processed product is dark green or emerald green.

10. A product obtained by the process of any one of claims 1 to 9.