Method for simultaneously producing purple perilla seed kernel oil and purple perilla seed kernel crude protein powder

Abstract

The invention relates to the technical field of food processing, in particular to a method for simultaneously producing purple perilla seed kernel oil and purple perilla seed kernel crude protein powder. The invention provides a method for simultaneously producing purple perilla seed oil and purple perilla seed crude protein powder, the method is a processing method for fully utilizing medicinal and edible purple perilla seeds, the purple perilla seed oil and the purple perilla seed crude protein powder can be simultaneously obtained, the quality of the purple perilla seed oil is greatly improved by the method provided by the invention, and the purple perilla seed oil and the purple perilla seed crude protein powder can be used for preparing the purple perilla seed oil and the purple perilla seed crude protein powder. Specifically, the content of omega-3 unsaturated fatty acid in the perilla seed kernel oil is increased (more than 65%), and the quality content is ensured to be stable; the content of functional nutrient substances (total sterol, squalene, vitamin E and the like) in the perilla seed kernel oil is increased. Meanwhile, the whole process of the method is low in temperature and adopts a pure physical method, loss and damage of nutritional functional substances caused by long-time high temperature and chemical refining are prevented, and the method has the advantages of green and environment-friendly product, low-carbon and environment-friendly process and simplicity in operation.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, in particular to a method for simultaneously producing perilla seed kernel oil and perilla seed kernel crude protein powder. Background Art

[0002] Perilla (Perilla frutescens (L.) is one of the first batch of medicinal and edible plants promulgated. It is a crop with strong ethnic characteristics in Guizhou and has important economic value and development value. The α-linolenic acid content of perilla oil is between 60-70%. It is known as "plant brain gold" by the medical community and is an ideal plant oil to replace "deep-sea fish oil". In recent years, as the efficacy of α-linolenic acid in promoting brain development and fighting cancer has been widely recognized, the health and medical functions of its seeds, leaves and stems have attracted much attention from scholars at home and abroad. As an important crop for people's life and health, according to the development needs of the perilla industry, the present invention intends to break through the technical bottleneck of the deep processing of perilla seeds, give full play to the application benefits of perilla seeds, and develop perilla health products suitable for the general public.

[0003] Perilla seeds have a high oil content. Perilla seed kernel oil is a new type of edible vegetable oil rich in ω-3, with an oil content of up to 45%. Its α-linolenic acid content is 60-70%, which belongs to ω-3 polyunsaturated fatty acids and has important probiotic effects on the human body. However, it is difficult to supplement ω-3 unsaturated fatty acids in regular diets, resulting in an extremely insufficient intake of α-linolenic acid. Therefore, perilla seeds have a high development and application value. Perilla seed kernel cake (perilla cake meal) is a byproduct of defatted perilla seeds. It has a crude protein content of up to 32.33%, contains 7.48% crude fat, 8.58% crude ash and 35.49% crude fiber, has an aromatic taste, excellent taste, high protein content and few impurities. Unlike rapeseed meal and cottonseed meal, the content of glucosinolates and degradation products and toxic components of cottonpol in perilla cake meal is very low, and there are no other substances harmful to human health. Perilla cake is also rich in essential amino acids, and the ratio of essential amino acids is balanced. Its efficacy ratio, net protein ratio and true digestibility are all very high. It is a very good plant protein resource and also a very good feed resource.

[0004] The pressing method is a traditional method for extracting vegetable oils, which uses mechanical external force to squeeze the oil out of the raw materials. This method has the advantages of simple process operation, high production safety, and a wide range of applications. However, this method will result in low oil quality of oil crops, low comprehensive utilization rate of raw materials, and a large loss of active ingredients in the oil.

[0005] Perilla seeds are currently processed by "steaming and frying - pressing" to obtain perilla seed kernel oil, and then a series of processes such as "deacidification, degumming, decolorization, dehydration, deodorization, and dewaxing" are used to remove solid impurities, free fatty acids, phospholipids, gum, wax, pigments, odors, etc. contained in the perilla seed kernel oil. However, perilla seed kernel oil undergoes multiple high-temperature refining and sodium hydroxide strong alkaline reactions, and the unsaturated fatty acids in the perilla seed kernel oil are decomposed by heat, and functional nutrients (squalene, sitosterol, vitamin E, etc.) are lost in large quantities, resulting in the current processed perilla seed kernel oil. The linolenic acid content is generally only 58%, affecting the overall quality, efficacy, flavor, shelf life, etc. of perilla seed kernel oil.

[0006] It can be seen from this that the α-linolenic acid in perilla seed kernel oil obtained by traditional processing is destroyed, resulting in a large nutritional loss, the product development on the market is relatively single, and the overall output of perilla seed kernel oil at home and abroad is small.

[0007] The residue after squeezing perilla seeds (perilla seed cake) can be further processed into products such as protein, peptide, perilla sauce, etc., and trace active ingredients such as polysaccharides and flavonoids can also be extracted. In recent years, new products such as perilla sauce, perilla powder, and fermented milk have been developed for perilla seed cake. Perilla sauce produced by co-fermentation of perilla seed meal and soybean meal as raw materials not only makes full use of the protein, polysaccharide and oil in perilla seed meal, realizes the full nutritional utilization of perilla seed meal, but also has the nutrition and flavor of traditional soybean paste, integrating seasoning, flavoring and health care. Fermented perilla powder is prepared from perilla seed meal as raw material, and perilla powder bread can be produced by adding fermented perilla powder to bread crumbs. Its water retention, aging degree, starch aging enthalpy value and fat oxidation degree during storage are better than those of the blank group without perilla powder. In addition, perilla seed meal is fermented to produce flavored fermented milk with a unique aroma of perilla, and perilla seed meal can be directly added to peach crisp raw materials to produce perilla seed meal peach crisp.

[0008] Therefore, high-quality processing of perilla seeds and utilization of their cakes have become a research hotspot, but the deep processing of peeled perilla seed kernels has not been reported. Summary of the invention

[0009] The purpose of the present invention is to provide a method for simultaneously producing perilla seed kernel oil and perilla seed kernel crude protein powder, so as to solve the problems existing in the above-mentioned prior art. The present invention provides a method for deep processing of peeled perilla seed kernels, which can simultaneously produce perilla seed kernel oil and perilla seed kernel crude protein powder, and the content of ω-3 unsaturated fatty acids in the obtained perilla seed kernels is above 65%.

[0010] To achieve the above object, the present invention provides the following solutions:

[0011] The present invention provides a method for simultaneously producing perilla seed kernel oil (perilla oil) and perilla seed kernel crude protein powder (perilla kernel crude protein), comprising the following steps:

[0012] The perilla seed kernels are subjected to low temperature pressing and physical filtration in sequence to obtain the perilla seed kernel oil and perilla seed kernel crude protein;

[0013] Grinding the perilla seed kernel crude protein to obtain the perilla seed kernel crude protein powder;

[0014] The low temperature pressing comprises a first low temperature pressing, microwave drying and a second low temperature pressing;

[0015] The physical filtration includes low temperature filtration, cooling crystallization and low temperature fine filtration.

[0016] Preferably, the first low-temperature pressing has a pressing temperature of ≤30°C and a pressing time of 30 minutes;

[0017] And / or, the pressure of the first low-temperature pressing is 60 MPa;

[0018] And / or, during the first low-temperature pressing, the moisture content of the perilla seed kernels entering the pressing is 5%, the entering temperature is ≤30° C., and the pressing time is 60 min.

[0019] Preferably, the temperatures of the drying box used in the microwave drying are set to 120° C., 130° C. and 120° C. respectively; and the conveyor belt speed of the microwave drying is 2 m / min.

[0020] Preferably, the second low-temperature pressing has a pressing temperature of ≤30°C and a pressing time of 300 min;

[0021] And / or, the pressure of the second low-temperature pressing is 80 MPa and the time is 300 min;

[0022] And / or, during the second low-temperature pressing, the moisture content of the dried perilla seed kernel cake obtained by microwave drying is less than 5%.

[0023] Preferably, the temperature of the low-temperature filtration is ≤10°C and the pressure is ≤0.35MPa.

[0024] Preferably, the cooling crystallization temperature is 0-4°C and the time is 48h.

[0025] Preferably, the temperature of the low-temperature fine filtration is 5-10°C.

[0026] Preferably, the method for preparing the perilla seed kernels comprises the steps of sequentially performing low-temperature drying, impurity removal, grading, peeling and separation, and color sorting and separation on the perilla seeds to obtain the perilla seed kernels.

[0027] Preferably, the microwave temperature is 120° C. and the time is 5 min.

[0028] Preferably, the classification standard is:

[0029] Perilla seeds with a diameter of more than 1.6 mm are large seeds; those with a diameter of 1.4-1.6 mm are medium seeds; and those with a diameter of less than 1.4 mm are small seeds.

[0030] And / or, the low-temperature drying is performed at a temperature of 45° C. and for a time of 8-10 hours.

[0031] Perilla seeds have a high moisture content, which not only makes them prone to mold and caking, but also makes them difficult to store safely, and seriously affects the quality of high-quality perilla oil. Removing moisture from perilla seeds through low-temperature drying can not only ensure safe storage, improve the quality and peeling efficiency of perilla seeds, but also significantly improve the oxidative stability of perilla seeds.

[0032] The principle of the peeling and separation (seed kernel sorting and screening) described in the present invention is to utilize the different specific gravity of kernel and seed, that is: the specific gravity of kernel is large, the specific gravity of seed is small, kernel will move onto the sieve, seed will move downward, and the kernel and seed can be seen to be separated by naked eyes on the sieve surface. The unpeeled perilla seeds are circulated to the previous seed kernel separation sieve through the suction return system, and finally return to the perilla seed peeling machine for peeling. At this time, the perilla seed peeling and sorting unit is designed as an automatic cycle peeling and sorting process. After peeling, clean the sieve surface and clean up in time. The present invention adopts the centrifugal peeling and separation technology of perilla seeds, which breaks through the technical bottleneck of the deep processing of perilla seed peeling. The perilla seed peeling method provided by the present invention is used for peeling, and the peeling rate of perilla seeds reaches 99%. After the perilla seeds are peeled, the perilla kernels are obtained, and the skin content (seed content) is ≤1%, and the broken kernel rate in the skin is ≤2%, that is, the pure kernel rate of perilla is ≥99%.

[0033] The present invention discloses the following technical effects:

[0034] The invention provides a method for producing perilla seed kernel oil and perilla seed kernel crude protein powder at the same time. The method is a processing method that makes full use of perilla seeds that are both medicinal and edible, and can obtain perilla seed kernel oil and perilla seed kernel crude protein powder at the same time. Through the method provided by the invention, the quality and quality of perilla seed kernel oil have been greatly improved, which is specifically reflected in: increasing the content of ω-3 unsaturated fatty acids in perilla seed kernel oil (more than 65%) to ensure stable quality content; increasing the content of functional nutrients (total sterols, squalene, vitamin E, etc.) in perilla seed kernel oil. At the same time, the method is low temperature throughout the whole process, and a pure physical method is used throughout the whole process to prevent the loss and destruction of nutritional functional substances caused by long-term high temperature and chemical refining. At the same time, it also has the advantages of green and environmentally friendly products, low-carbon and environmentally friendly processes, and simple operation. In addition, the perilla seed kernel oil obtained by the method provided by the invention has good color, high nutritional content, and good palatability; and the perilla seed kernel cake (perilla cake meal) is fully utilized to improve the utilization rate of the perilla seed kernel cake; the invention uses the perilla seed kernel cake to develop a perilla seed kernel crude protein powder with high nutritional content. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 The present invention is a flow chart for the preparation of perilla seed kernel oil and perilla seed kernel crude protein powder. DETAILED DESCRIPTION

[0037] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0038] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0039] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0040] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0041] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0042] Unless otherwise specified, the methods used in the present invention are all methods well known to those skilled in the art.

[0043] Example 1

[0044] Process such as Figure 1 shown.

[0045] 1. Raw materials:

[0046] The raw materials used in this embodiment are: high-linolenic acid perilla seeds produced by Qisu No. 3 of the Rapeseed Institute of Guizhou Academy of Agricultural Sciences, which are industrialized ("company + agricultural technology department + farmers") order-made in low-temperature, cold and low-sunlight areas above 1,300 m in high-altitude mountainous areas of Guizhou (such as Changshun, Xingren, Hezhang, etc.) to obtain perilla seeds with high linolenic acid content, and the farmers are required to dry and clean the produced raw materials in time to reduce the moisture content to less than 8%, and impurities are removed by air separation and screening, and then recycled into the warehouse; the high-linolenic acid perilla seeds have an oil content of 45% (oil content is fat content), a protein content of 20%, and an α-linolenic acid content of 65-69%, which is as high as 69.73%, which is 5%-8% higher than the α-linolenic acid content in ordinary perilla seeds.

[0047] Table 1 Analysis of linolenic acid content in Qisu No. 3 at different altitudes

[0048] area Kaiyang Changshun Xingren Hezhang altitude 910m 1280m 1430m 1760m 2023 62.32 65.15 67.26 69.08 2024 63.44 66.14 68.43 69.73

[0049] 2. Low temperature drying

[0050] The moisture content of high-quality high-linolenic perilla seeds is relatively high, generally 8-12%. In order to safely store and peel the high-linolenic perilla seeds, the high-linolenic perilla seeds are purchased and stored, and low-temperature drying technology is used within 1-3 days to reduce the moisture content of the high-linolenic perilla seeds to less than 5%. In this embodiment, a flat-bed static low-temperature dryer is selected to dry the seeds with hot air at a low temperature of 45°C for 8-10 hours, and the moisture content is slowly reduced from 8-12% to 5%, and dried perilla seeds are obtained, and then stone removal and cleaning are carried out.

[0051] 3. Clean up

[0052] High linolenic acid perilla seeds contain mud, sand, broken leaves, impurities and other impurities. Stone removers and 5XJC-5A seed selection vehicles are used. High linolenic acid perilla seeds are winnowed and de-stoned to remove ash, mud, broken leaves, impurities, small seeds, etc., to obtain clean, uniform and high-quality high linolenic acid perilla seeds.

[0053] 4. Grading

[0054] After the perilla seeds are dried and impurities removed, they are divided into different specifications and grades according to the diameter of the perilla seeds. The specific steps are: the dried perilla seeds pass through the upper hopper and enter the bucket elevator, and the dried perilla seeds are lifted and transported to the grading screen. The grading screen divides the dried perilla seeds into 3 large, medium and small grades. The large standard: diameter > 1.6mm is large perilla seeds, the medium standard: diameter 1.4-1.6mm is medium perilla seeds, and the small standard: diameter < 1.4mm is small perilla seeds.

[0055] Large-grain perilla seeds, medium-grain perilla seeds and small-grain perilla seeds are quantitatively packed into fixed containers or woven bags respectively, and the grades of the perilla seeds are marked for processing.

[0056] 5. Peeling and separation

[0057] After the perilla seeds are graded, the large and medium perilla seeds are peeled for deep processing, and the small perilla seeds are subjected to other processing.

[0058] The large-grain perilla seeds and the medium-grain perilla seeds are peeled and separated in batches respectively. The peeling and separation machine used is TFSZ-300. The specific steps of peeling and separation are as follows: the perilla seed raw materials (large-grain perilla seeds or medium-grain perilla seeds) first pass through the upper hopper and enter the bucket elevator. The elevator transports the perilla seed raw materials to the perilla seed shelling machine. The motor speed is 1000-1300rpm / min. The perilla seed shelling machine shells the perilla seeds using the centrifugal shelling principle. The perilla seed peeling and sorting unit is designed as an automatic cycle peeling and sorting process. After shelling, the mixture contains perilla kernels, perilla seed husks and unhulled perilla seeds; the perilla seed husks are then sucked out by air selection and collected separately; the perilla kernels and unhulled perilla seeds are passed through three vibrating sorting screens to fully sort and separate the perilla seeds and perilla kernels, and finally the perilla seed hairy kernels are obtained, the perilla seed hairy kernels contain ≤5% of seeds, of which the perilla kernels are ≥95%.

[0059] 6. Color sorting and separation

[0060] The raw perilla seeds (containing seeds ≤5%) are separated by color sorting machine. Before color sorting, check whether there are any debris in the equipment line and the hopper of the color sorter. Then turn on the air compressor and wait for the pressure to reach the value of 4Mpa. Then use the pressure gun to blow away the ash in the color sorter. Open the feed port and adjust the feed speed according to the peeling effect of the raw perilla seeds. If the peeling effect is good (containing seeds ≤5%), the feed speed is set to 40 and the color sorting value is set to 80. Pure perilla seeds can be obtained, the pure perilla kernel rate is ≥99%, and the seed content in the perilla kernel is ≤1%. Through the selection and separation, the purity of the perilla kernel is greatly improved. At the same time, the fat content and protein content in the perilla kernel are also improved.

[0061] After that, the perilla seed kernel was tested and analyzed: it contains 51.0% fat, 27.2% protein, 20.36% amino acid, 3250mg / kg calcium, 6680mg / kg potassium, 3280mg / kg magnesium, 53.6mg / kg iron, 58.4mg / kg zinc, 18.1mg / kg manganese, 18.7mg / kg copper, 21.8mg / kg strontium, etc. It is also rich in squalene, sitosterol, etc.

[0062] 7. Low temperature pressing

[0063] After peeling and color sorting of high linolenic acid perilla seeds, pure perilla kernels were obtained. Due to the influence of physical properties during the screw pressing process, it was difficult to build up pressure for the pure perilla kernels. Therefore, the following steps were performed:

[0064] 7.1. Initial low temperature pressing

[0065] In order to fully increase the content of ω-3 unsaturated fatty acids in perilla seed kernel oil, reduce wax, acid value and peroxide value, it was determined through screening that a 4-column hydraulic oil press was used for primary pressing. The best conditions were: 5% inlet moisture, ≤30°C inlet temperature, 10-25°C ambient temperature, no protein deformation in the pressed cake, and the comprehensive oil temperature of the oil output was lower than 30°C; prevent high temperature pressing from increasing acid value, peroxide, wax, polycyclic aromatic hydrocarbons, etc. The specific steps are as follows:

[0066] First, put the pure perilla kernels into a cotton hydraulic bag and set the best conditions: the moisture content of the pure perilla kernels entering the press is 5%, the temperature of the raw materials entering the press is controlled within 30°C, and the ambient temperature is 10-25°C; take about 7.5kg of pure perilla kernels, put the pure perilla kernels into the pressing cylinder according to the pressing procedure, and press the start button. With hydraulic oil as the medium, the hydraulic rod is driven by the power of the hydraulic pump, so that the hydraulic column is gradually subjected to force to achieve the purpose of pressing the perilla kernels. When the press machine slowly increases the pressure, the perilla seed kernel oil is slowly squeezed out. The whole pressure-increasing process lasts about 15 minutes. The pressure will be increased to a maximum of 60MPa for fixed pressure pressing. The pressure-increasing procedure is to first check and clean the hydraulic press and the barrel, then put the material into the barrel, adjust the pressure time according to the panel, and finally press the start button until the pressure is slowly increased. The temperature of the oil press is kept within 38.0℃, and then the pressure is maintained at 60MPa for 45 minutes. The entire process of the first low-temperature pressing takes a total of 60 minutes. Depending on whether the oil flowing out of the gap between the pressing bars forms a line, the pressure holding time can be appropriately reduced or extended by 5-10 minutes. If it forms a line, the pressure holding time is extended, otherwise it is reduced. After pressing, the pressed products were investigated, and the results showed that about 2.25 kg of crude oil was produced at a single time, with an oil yield of 30%; about 5.25 kg of kernel meal was produced, with a kernel cake yield of 70%; the crude perilla kernel oil was stored in a 10°C refrigerator, and the kernel cake was placed in a stainless steel barrel for secondary processing.

[0067] 7.2 Microwave drying

[0068] The perilla kernel cake after the initial squeezing needs to be flavored by a microwave rapid drying method. The three microwave temperature bins are set to 120°C, 130°C, and 120°C for drying. When the bin temperature rises to the set temperature, the perilla kernel cake after the initial squeezing is placed in the microwave feeding port. The color and aroma of the perilla kernel cake at the microwave discharge port are judged. If it is light yellow with a unique roasted aroma, the running speed is appropriate. If the roasted aroma is too strong or the color is too dark, the speed of the microwave material conveyor belt needs to be accelerated. In this embodiment, the microwave temperatures are 120°C, 130°C, and 120°C, and the material conveyor belt speed is 2m / min.

[0069] The fast and appropriate temperature and the appropriate material conveyor belt speed help to achieve the purpose of drying, flavoring and puffing the material. At the same time, after the initial extraction, the linolenic acid in the perilla kernel oil is less damaged, and the moisture of the material can be controlled at around 5%. The microwave-dried perilla kernel cake material is placed in a stainless steel tank and quickly cooled to room temperature of around 25°C by cold air.

[0070] 7.3. Secondary low temperature pressing

[0071] In order to increase the oil yield of perilla kernels and the protein content of perilla kernel cakes, a multi-layer high-pressure hydraulic oil press is selected to perform a second pressing on the dried perilla kernel cake material. If the moisture content of the material is too high, the material will easily be squeezed out from the gaps in the pressing bars during the pressing process. Therefore, it is necessary to ensure that the moisture content of the material is low enough (moisture content within 5%), and the temperature of the raw materials entering the press is controlled within 30°C. Then, the microwave-dried perilla kernel cake material is placed layer by layer in the press barrel, and the temperature entering the press is controlled at 15-30°C. Ensure that there is a pressing plate on each layer, start the oil press, and slowly increase the pressure. The pressure-increasing procedure is to clean the oil press, put the material in the barrel, set the pressure to 80Mpa, set the single interval hydraulic time (pressurize once every 30 seconds), and press the start button. Start oil pressing, reach the maximum pressure value of 80MPa, the temperature of the oil press is controlled within 38.0℃, the whole pressure increase process will last for 10-20min, adjust the interval single pressing time according to the oil output in the gap of the pressing bar, when the oil output is in line, the single interval pressing time interval needs to be slowly shortened, the whole secondary low temperature time lasts for 300min, and the second perilla seed kernel crude oil and the second perilla seed kernel cake are obtained respectively, the second perilla seed kernel crude oil is put into a 10℃ refrigerator for refrigeration, the second perilla seed kernel cake is put into a stainless steel barrel, the perilla seed kernel cake is broken, and quantitative vacuum packaging is carried out for processing. The squeezing products of this step were investigated, and the results showed that the single squeezing amount was 30kg, the oil output was 8.75kg, and the perilla seed kernel cake was 21kg.

[0072] 8. Pure physical filtration (low temperature freezing filtration)

[0073] 8.1. Low temperature filtration

[0074] In order to retain the natural active functional nutrients of perilla seed kernel oil to the maximum extent and improve the pure natural nutrients of perilla seed kernel oil, low-temperature filtration is adopted, that is, the squeezed perilla seed kernel crude oil is fully cooled to a low temperature below 10°C, and a 1μm filter cloth plate and frame filter is used for the first filtration. The filter pressure does not exceed 0.35MPa to remove impurities and most of the wax in the crude oil and obtain low-temperature filtered perilla seed kernel oil.

[0075] 8.2 Cooling crystallization

[0076] The low-temperature filtered perilla seed kernel oil contains a small amount of wax and impurities, which affect the appearance quality of the product. After the initial filtration (low-temperature filtration) of the perilla seed kernel crude oil, it is placed in a cooling room at room temperature of 0-4°C for cooling and crystallization for 48 hours, that is, the low-temperature filtered perilla seed kernel oil is crystallized and cooled in the cooling room tank, and the final oil temperature is 2-4°C. In the first 24 hours of cooling and crystallization, the cooling rate of the perilla seed kernel oil is about 1°C per hour, and the total cooling in the next 24 hours is about 1-2°C, and finally reaches a temperature of 2-4°C, and the perilla seed kernel oil with good cooling and crystallization is obtained.

[0077] 8.3 Low temperature fine filtration

[0078] The cooled and crystallized perilla seed kernel oil is finely filtered using a stainless steel plate and frame filter, and the "filter paper + filter cloth" method is used for fine filtration. The pore size of the filter paper is required to be 0.5 μm, and the pore size of the filter cloth is 3 μm. The filtration is carried out in a low-temperature cold storage room, maintaining the room temperature at 5-10°C to obtain low-temperature fine-filtered perilla seed kernel oil, which is stored in a 304 stainless steel oil storage tank at 0-4°C for filling.

[0079] The low-temperature fine-filtered perilla seed kernel oil was subjected to a freezing test at 0°C. The results showed that the low-temperature fine-filtered perilla seed kernel oil remained transparent and clear after being frozen for more than 4 hours.

[0080] 9. Grading and precision filling

[0081] The low-temperature fine-filtered perilla seed kernel oil was tested and graded into special-grade perilla seed kernel oil and superior-grade perilla seed kernel oil. The standards for special and superior grades are shown in Tables 1 and 2. Afterwards, they were bottled according to grade. Special-grade perilla seed kernel oil was bottled in small glass bottles with a precision of 3 mL, and superior-grade perilla seed kernel oil was bottled in glass bottles with a volume of about 100 mL for consumption. The super-grade perilla seed kernel oil (pure natural super-grade perilla seed kernel oil) has a natural golden and translucent color, a pure and fragrant smell, and no peculiar smell. The physical and chemical indicators of the product after testing are: water and volatile matter content 0.04%, insoluble impurity content 0.01%, acid value 0.43mg / g, peroxide value 0.06g / 100g, benzopyrene not detected, aflatoxin not detected, and solvent residue not detected (Table 2); Nutritional indicators: linolenic acid content 69.51%, total sterol 5238mg / kg, squalene 178.53mg / kg, total carotene 5190μg / 100g (Table 2). The test results are consistent with the super-grade perilla seed kernel oil (Table 3, Table 4), and a small glass 3mL precision filling is used, and then a matching straw is installed in the package to obtain a super-grade direct drinking perilla seed kernel oil product. If the perilla seed kernel oil is graded as superior grade, fill it into a glass bottle of about 100 mL for consumption, affix a label, and complete the product packaging.

[0082] Table 2 Example Perilla seed oil nutritional classification index

[0083]

[0084] Table 3 Physical and chemical indicators of premium perilla seed oil

[0085] index Test data Moisture and volatile matter content / (%) 0.10 Insoluble impurities content / (%) 0.05 Acid value (KOH) / (mg / g)≤ 1.5 Peroxide value / (g / 100g)≤ 0.15 Aflatoxin B1 / (μg / kg)≤ 1 Benzo(a)pyrene / (μg / kg)≤ 1 Residual solvent / (mg / kg)≤ Not to be detected

[0086] Table 4 Nutritional grading indexes of special grade perilla seed kernel oil and superior grade perilla seed kernel oil

[0087]

[0088] 10. Processing of high-protein perilla seed kernel crude protein powder

[0089] Perilla seed kernel cake is a by-product of peeled perilla seed kernels after two low-temperature pressings. The perilla seed kernel cake needs to be further processed into semi-finished products. The perilla seed kernel cake is subjected to microwave dehumidification, which also has the functions of maturation, flavor enhancement and sterilization to obtain high-protein perilla seed kernel powder.

[0090] In this embodiment, microwave dehumidification is performed by microwave drying machine 45HMV-6X at a temperature of 120° C. for 5 min, then cooled to room temperature, and then crushed by ultrafine pulverizer to obtain 200 mesh, 300 mesh, etc. perilla seed kernel crude protein powder, and then quantitatively packaged into 5kg and 10kg for stand-alone use.

[0091] At the same time, the nutrients in the peeled and separated peeled perilla seed kernels and the 200-mesh perilla kernel crude protein obtained by the preparation method provided by the present invention were investigated, and the results are shown in Table 3. The crude fat content of the perilla kernel crude protein powder prepared by the method provided by the present invention is 9.0% (Table 5), the crude protein content is as high as 53.93%, the amino acid content is 43.40%, and the total dietary fiber content is 27.56%; it contains a large amount of mineral elements required by the human body, such as calcium content of 6140mg / kg, potassium content of 11970mg / kg, magnesium content of 5970mg / kg, etc.; it also contains a large amount of trace elements, such as iron content of 91.62mg / kg, copper content of 36.50mg / kg, zinc content of 108.60mg / kg, strontium content of 40.97mg / kg, manganese content of 33.37mg / kg, nickel content of 7.49mg / kg, etc.; by comparing the contents of various components of the perilla crude protein powder with those of the peeled perilla kernel, it can be seen that, except for the contents of crude fat and crude protein, the contents of other components of the perilla crude protein are significantly higher than those of the peeled perilla kernel.

[0092] It can be seen that the perilla seed kernel crude protein powder obtained by the method provided by the present invention not only has a crude protein content of up to 53.93%, but also contains 66.6% of α-linolenic acid fat, a large amount of mineral elements calcium, magnesium, and potassium required by the human body, essential trace elements iron, copper, zinc, strontium, manganese, nickel, etc., vitamin E, vitamin B2, etc., is rich in nutrition, is a high-quality semi-finished product for preparing meal replacement powder and developing perilla milk, and can also be directly ultra-finely crushed and packaged into 20g and 30g perilla seed kernel crude protein powder products.

[0093] Table 5 Comparative analysis of the content of perilla seed kernels before and after pressing

[0094]

[0095] Example 2 Omega 3 Perilla Seed Kernel Oil (ω-3 Perilla Seed Kernel Oil)

[0096] The high linolenic acid perilla seeds were processed by the steps of Example 1 to obtain premium perilla seed kernel oil, which was quantitatively filled in a 3 mL glass bottle to obtain premium perilla seed kernel oil. After inspection, it was found that: the water and volatile content was 0.05%, the insoluble impurity content was 0.01%, the acid value was 0.55 mg / g, the peroxide value was 0.09 g / 100 g, benzopyrene was not detected, aflatoxin was not detected, and the solvent residue was not detected. The α-linolenic acid content was 67.8%, and the total amount of sterols was 4.33×10 3 mg / kg, squalene is 263.20mg / kg, and carotene content is 5.40×10 3 μg / 100g (Table 2).

[0097] Example 3 (ω-3 Perilla seed oil)

[0098] The high linolenic acid perilla seeds were processed according to the steps of Example 1 to obtain premium perilla seed kernel oil, which was quantitatively filled in 3 mL glass bottles to obtain ω-3 premium perilla seed kernel oil products. The products were tested as follows: the perilla seed kernel oil had a moisture and volatile matter content of 0.05%, an insoluble impurity content of 0.01%, an acid value of 0.66 mg / g, a peroxide value of 0.07 g / 100 g, an α-linolenic acid content of 68.39%, and a total sterol content of 4.89 × 10 3 mg / kg, squalene is 146.09mg / kg, and carotene content is 4.89×10 3 μg / 100g (Table 2).

[0099] Comparative Example 1

[0100] The steps are the same as those in Example 1, except that in the low-temperature pressing process, the peeled perilla kernel was selected and only one low-temperature 60 MPa pressing step was performed. The obtained perilla kernel oil was tested and found to have the following contents: water content and volatile matter content were 0.04% (Table 6), insoluble impurity content was 0.01%, acid value was 0.33 mg / g, peroxide value was 0.05 g / 100 g, benzopyrene was not detected, aflatoxin was not detected, and solvent residue was not detected. The α-linolenic acid content was 68.50%, and the total amount of sterols was 4.96×10 3 mg / kg, squalene is 157.38mg / kg, and carotene content is 5.16×10 3 μg / 100g, reaching the index of premium perilla kernel oil. However, the crude fat content of perilla kernel crude protein powder is 38.9% (Table 7), the residual oil rate is very high, the crude protein content is not high, the crude protein content is 36.20%, the amino acid content is 29.20%, and the total dietary fiber content is 18.50%, which are significantly lower than those in Example 1; the calcium content of 4120mg / kg, potassium content of 8040mg / kg, and magnesium content of 4010mg / kg, which are a large number of mineral elements required by the human body, are also significantly lower than those in Example 1.

[0101] Comparative Example 2

[0102] The steps are the same as those in Example 1, except that in the low-temperature pressing process, the peeled perilla kernels were selected and only subjected to the low-temperature pressing step of 60 MPa twice. The obtained perilla kernel oil was tested and found to have the following contents: water content and volatile matter content of 0.05% (Table 6), insoluble impurity content of 0.01%, acid value of 0.45 mg / g, peroxide value of 0.06 g / 100 g, no benzopyrene, no aflatoxin, and no solvent residue. The α-linolenic acid content was 68.32%, and the total amount of sterols was 4.83×10 3 mg / kg, squalene is 163.22mg / kg, and carotene content is 5.10×10 3μg / 100g, reaching the index of premium perilla seed oil. However, the crude fat content of perilla seed crude protein powder is 14.80% (Table 7), the residual oil rate is relatively high, the crude protein content is 47.69%, the amino acid content is 38.47%, the total dietary fiber content is 24.37%, etc., which are significantly lower than those in Example 1; the calcium content is 5482mg / kg, the potassium content is 10592mg / kg, and the magnesium content is 5283mg / kg, etc., which are also significantly lower than those in Example 1.

[0103] Comparative Example 3

[0104] The steps are the same as those in Example 1, except that: in the low-temperature pressing process, unpeeled perilla seeds were selected and the step of 60MPa low-temperature pressing was carried out twice. The steps are the same as those in Example 1, except that: in the low-temperature pressing process, peeled perilla seeds were selected and the step of 60MPa low-temperature pressing was carried out twice. The obtained perilla seed oil was tested and found to have the following contents: water and volatile matter content 0.07% (Table 6), insoluble impurity content 0.02%, acid value 1.33mg / g, peroxide value 0.10g / 100g, benzopyrene 0.04μg / kg, aflatoxin 0.12μg / kg, and solvent residue was not detected. The α-linolenic acid content was 67.05%, and the total amount of sterols was 4.82×10 3 mg / kg, squalene is 137.58mg / kg, and carotene content is 4.69×10 3 μg / 100g, reaching the index of premium perilla seed oil. However, the crude fat content of perilla seed crude protein powder is 13.60% (Table 7), the residual oil rate is relatively high, the crude protein content is 29.68%, and the amino acid content is 25.81%, which is significantly lower than that of Example 1; the calcium content is 5715mg / kg, potassium is 7463mg / kg, and magnesium is 4058g / kg, which is also significantly lower than that of Example 1, but the dietary fiber content is 39.76%, which is significantly increased.

[0105] Comparative Example 4

[0106] The steps are the same as those in Example 1, except that: in the low-temperature pressing process, unpeeled perilla seeds were selected and pressed twice by a low-temperature double-bolt oil press. The steps are the same as those in Example 1, and the perilla seed oil obtained is tested to have the following contents: water and volatile matter content 0.08% (Table 6), insoluble impurity content 0.03%, acid value 2.5 mg / g, peroxide value 0.18 g / 100 g, benzopyrene 0.21 μg / kg, aflatoxin 0.17 μg / kg, and no residual solvent. The α-linolenic acid content is 66.21%, and the total amount of sterols is 4.01×10 3 mg / kg, squalene is 115.9mg / kg, and carotene content is 4.43×10 3μg / 100g, its acid value and peroxide value are significantly increased, and it cannot reach the index of special grade perilla kernel oil. However, the crude fat content of perilla seed cake crude protein powder is 11% (Table 7), the crude protein content is 31.86%, and the amino acid content is 26.21%. The protein and amino acid content is not high, and the content is significantly lower than that in Example 1; it contains a large amount of mineral elements required by the human body, such as calcium 5730mg / kg, potassium 7490mg / kg, and magnesium 4060mg / kg, which are also significantly lower than those in Example 1; the dietary fiber content is 40.90% significantly increased.

[0107] Table 6 Nutritional grading indexes of perilla seed kernel oil in different comparative examples

[0108]

[0109] Table 7 Comparative analysis of the content of crude protein powder of perilla seed kernel

[0110]

[0111]

[0112] As shown in Tables 6 and 7, the difference in Comparative Example 1 is that the peeled perilla seeds were pressed at low temperature at 60 MPa once, and the crude fat content of the crude protein powder of the perilla seeds was ≤40%, the crude protein content was not high, and the residual oil rate of the perilla seeds cake was also very high. The difference in Comparative Example 2 is that the peeled perilla seeds were pressed at low temperature at 60 MPa twice, and the crude protein content of the crude protein powder of the perilla seeds was ≤50%, the crude protein content was high, and the residual oil rate of the perilla seeds cake was also high. The difference in Comparative Example 3 is that the unpeeled perilla seeds were pressed at low temperature at 60 MPa twice, and the acid value and peroxide value of the perilla seed oil were increased, benzopyrene and aflatoxin were detectable, the crude protein content of the perilla seed crude protein powder was ≤30%, and the cellulose was significantly increased. The difference of Comparative Example 4 is that the unpeeled perilla seeds are selected and pressed by a low-temperature double-bolt oil press twice. The acid value and peroxide value of the perilla seed oil obtained are significantly increased, and the benzopyrene and aflatoxin values ​​are also increased, which cannot reach the index of premium perilla seed oil; the crude protein content is 31.86%, the amino acid content is 26.21%, the protein and amino acid contents are lower, and the dietary fiber content is significantly increased.

[0113] In summary, the method for simultaneously producing perilla seed kernel oil and perilla seed kernel crude protein powder provided by the present invention not only obtains high-quality special-grade perilla seed kernel oil rich in phytosterols, squalene, carotene, etc., but also obtains perilla seed kernel powder with a high crude protein content, wherein the crude protein content is ≥50%, the protein and amino acid contents are very high, and the powder contains a large amount of mineral elements such as calcium, potassium, magnesium, etc. required by the human body; and also contains a large amount of trace elements such as iron, copper, zinc, strontium, manganese, nickel, etc.

[0114] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for simultaneously producing perilla seed kernel oil and perilla seed kernel crude protein powder, characterized in that: The following steps are involved: The perilla seed kernels are subjected to low temperature pressing and physical filtration in sequence to obtain the perilla seed kernel oil and perilla seed kernel crude protein; Microwave and crush the crude protein of perilla seed kernel to obtain the crude protein powder of perilla seed kernel; The low temperature pressing comprises a first low temperature pressing, microwave drying and a second low temperature pressing; The physical filtration includes low temperature filtration, cooling crystallization and low temperature fine filtration.

2. The method according to claim 1, characterized in that The first low-temperature pressing has a pressing temperature of ≤30°C and a pressing time of 30 minutes; And / or, the pressure of the first low-temperature pressing is 60 MPa; And / or, during the first low-temperature pressing, the moisture content of the perilla seed kernels entering the pressing is 5%, the entering temperature is ≤30° C., and the pressing time is 60 min.

3. The method according to claim 1, characterized in that The temperatures of the drying boxes used in the microwave drying are set to 120° C., 130° C. and 120° C. respectively; the conveyor belt speed of the microwave drying is 2 m / min.

4. The method according to claim 1, characterized in that: The second low-temperature pressing has a pressing temperature of ≤30°C and a pressing time of 300 minutes; And / or, the pressure of the second low-temperature pressing is 80 MPa and the time is 300 min; And / or, during the second low-temperature pressing, the moisture content of the dried perilla seed kernel cake obtained by microwave drying is less than 5%.

5. The method according to claim 1, characterized in that The temperature of the low temperature filtration is ≤10°C and the pressure is ≤0.35MPa.

6. The method according to claim 1, characterized in that The temperature of the cooling crystallization is 0-4°C and the time is 48h.

7. The method according to claim 1, characterized in that The temperature of the low-temperature fine filtration is 5-10°C.

8. The method according to claim 1, characterized in that The temperature of the microwave is 120° C. and the time is 5 min.

9. The method according to claim 1, characterized in that: The preparation method of the perilla seed kernels comprises the steps of sequentially performing low-temperature drying, impurity removal, grading, peeling and separation, and color sorting and separation on the perilla seeds to obtain the perilla seed kernels.

10. The method according to claim 9, characterized in that The classification standards are: Perilla seeds with a diameter of more than 1.6 mm are large seeds; those with a diameter of 1.4-1.6 mm are medium seeds; and those with a diameter of less than 1.4 mm are small seeds. And / or, the low-temperature drying is performed at a temperature of 45° C. and for a time of 8-10 hours.

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