Chufa oil and a method for preparing the same

Abstract

The application relates to the technical field of food processing, and particularly discloses a preparation method of cyperus esculentus liquid, which comprises the following steps: preparing an enzyme slurry; grinding cyperus esculentus to prepare raw slurry; mixing the enzyme slurry and the raw slurry according to a predetermined ratio, and performing enzymolysis; pressurizing and homogenizing the enzymolysis product, and performing filtration and sterilization and enzyme inactivation to obtain the cyperus esculentus liquid. The application further discloses the cyperus esculentus liquid prepared by the above method, wherein the reducing sugar content of the cyperus esculentus liquid is 15%, and the protein hydrolysis degree is 6.95%. Through hydrolysis of the raw slurry by the enzyme slurry, the nutritional components in the raw slurry are released, the nutritional value of the cyperus esculentus liquid is improved, macromolecular substances in the cyperus esculentus are decomposed, turbidity and browning of the cyperus esculentus liquid are avoided, and the product stability is improved. Through the enzymolysis, the residue amount is reduced, and the flavor and taste of the cyperus esculentus liquid are improved.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and in particular to a tiger nut liquid and its preparation method. Background Technology

[0002] Tiger nuts are herbaceous oilseed crops with wide soil adaptability and strong meristematic activity. Their main components are: 20-30% oil, 20-30% starch, 20-25% soluble sugars, 8-10% dietary fiber, and 5-8% protein. They are rich in vitamins, minerals, and 17 amino acids, and have good preventative and therapeutic effects on heart disease, hypertension, hyperlipidemia, and cardiovascular and cerebrovascular diseases. They are an important raw material for making soy milk and soy products. Tiger nut soy milk is high in calcium, which helps prevent cardiovascular disease, diabetes, cataracts, organ aging diseases, bone deformities, and can also prevent osteoporosis, regulate insulin production and release, and prevent cell and tissue damage caused by various environmental hazards.

[0003] Chinese invention application (CN 111264626 A) discloses a method for preparing tiger nut-based soy milk, specifically involving raw material pretreatment → wet ultrafine grinding → ingredient mixing → volume adjustment → homogenization → filtration → ultra-high temperature instantaneous sterilization → aseptic filling to obtain tiger nut-based soy milk. However, because tiger nut itself contains a large amount of macromolecular substances, such as cellulose, starch, and protein, relying solely on homogenization and filtration results in a significant amount of residue in the product, and cannot solve issues such as turbidity and browning, leading to insufficient product stability, easy loss of nutrients, and negative impacts on flavor and taste. Summary of the Invention

[0004] Therefore, it is necessary to address the above-mentioned shortcomings by providing a tiger nut liquid with low sedimentation, stable product, and minimal loss of nutrients, as well as its preparation method.

[0005] A method for preparing tiger nut liquid includes the following steps:

[0006] Prepare enzyme syrup;

[0007] Tiger nuts are ground into a paste to prepare raw pulp;

[0008] The enzyme syrup and raw pulp are mixed in a predetermined ratio and then enzymatically hydrolyzed.

[0009] The enzymatic hydrolysis product is homogenized under pressure, then the ingredients are added and filtered to obtain soybean liquid slurry;

[0010] Sterilize and inactivate the enzymes in the soybean liquid raw pulp to obtain tiger pea liquid.

[0011] In one embodiment, the enzyme syrup is a mixture of α-amylase extracted from Bacillus licheniformis, amyloglucosidase extracted from Aspergillus niger, and α-amylase extracted from Bacillus liquefactionus.

[0012] In one embodiment, the enzyme syrup contains α-amylase extracted from Bacillus licheniformis with an enzyme activity of 1500-2500 U / g, amyloglucosidase extracted from Aspergillus niger with an enzyme activity of 1400-2000 U / g, and α-amylase extracted from Bacillus liquefaction with an enzyme activity of 1200-1700 U / g.

[0013] In one embodiment, the soybean syrup comprises the following components in parts by weight: 5-15 parts tiger nut powder, 1 part enzyme syrup, 30-70 parts water, 0-2 parts soybean protein, and 0-2 parts calcium carbonate.

[0014] In one embodiment, grinding the tiger nuts to prepare the raw pulp includes:

[0015] Grind the tiger nuts and pass them through a 200-mesh sieve;

[0016] Take the sieved material, add water, and wet grind it to produce raw pulp with a fineness of 300 mesh.

[0017] In one embodiment, the enzymatic hydrolysis temperature is 60–80°C and the enzymatic hydrolysis time is 0.5–1.5 h.

[0018] In one embodiment, the equipment used for sterilization and enzyme inactivation is an ultra-high temperature sterilizer, a steam exchanger, or a heat exchanger.

[0019] In one embodiment, the sterilization and enzyme inactivation operation lasts for at least 15 seconds, and the minimum sterilization and enzyme inactivation temperature is 118°C.

[0020] In one embodiment, the amount of sediment in the enzymatic hydrolysis product is less than 2.39%.

[0021] The present invention also discloses a tiger nut liquid, which is prepared by the above preparation method, wherein the tiger nut liquid has a reducing sugar content of 15% and a protein hydrolysis degree of 6.95%.

[0022] The present invention relates to tiger nut liquid and its preparation method, which involves preparing an enzyme syrup. The enzyme syrup hydrolyzes the raw tiger nut pulp, releasing the nutrients and sugars, thereby enhancing the nutritional value of the tiger nut liquid. Simultaneously, it decomposes the large molecules in the tiger nut, preventing turbidity and browning caused by the precipitation or spoilage of these large molecules, thus improving product stability and preventing nutrient loss. After enzymatic hydrolysis, the residue in the raw tiger nut pulp is further decomposed, reducing the amount of residue in the hydrolysis products, thereby improving the flavor and texture of the tiger nut liquid. Attached Figure Description

[0023] Figure 1This is a flowchart of a method for preparing tiger nut liquid in one embodiment of the present invention. Detailed Implementation

[0024] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] This invention discloses a method for preparing tiger nut liquid with low sedimentation, stable product quality, and minimal nutrient loss. The method involves an enzymatic process where an enzyme slurry is mixed with raw tiger nut pulp. The enzymes in the slurry hydrolyze the macromolecules in the raw tiger nut pulp, converting them into smaller sugar molecules. This prevents the sedimentation or spoilage of macromolecules during storage. The tiger nut liquid prepared using this enzymatic method is safe to drink directly and contains a high degree of protein hydrolysis, making it easily digestible and absorbable. It avoids the side effects of bloating and diarrhea that can occur when drinking pure soy milk, especially for those with indigestion, belching, or poor gastrointestinal function.

[0026] For details, please refer to Figure 1 The method for preparing tiger nut liquid in this embodiment includes the following steps:

[0027] S1: Prepare enzyme syrup.

[0028] In this embodiment, the enzyme syrup is a mixture of α-amylase extracted from Bacillus licheniformis, amylase extracted from Aspergillus niger, and α-amylase extracted from Bacillus liquefactionus. It should be noted that α-amylase can hydrolyze the α-1,4-glycosidic bonds within starch, producing dextrin, oligosaccharides, and monosaccharides. Amylase can hydrolyze the α-1,4- and α-1,6-glycosidic bonds of polysaccharides (starch, glycogen, etc.) to glucose. Mixing α-amylase and amylase with the desired enzyme activity can enhance the nutritional value of tiger nuts without affecting their taste.

[0029] Since excessive or insufficient enzyme activity will alter the proportion of the hydrolyzed molecules in the product, thus affecting the taste and flavor, in this embodiment, the enzyme activity of α-amylase extracted from Bacillus licheniformis is 1500-2500 U / g, the enzyme activity of amylase extracted from Aspergillus niger is 1400-2000 U / g, and the enzyme activity of α-amylase extracted from Bacillus liquefactionus is 1200-1700 U / g. It should be noted that the enzyme activity concentration may vary between products from different enzyme manufacturers. Therefore, in actual production and processing, the enzyme activity needs to be adjusted according to the product description to meet the enzyme activity requirements of various enzymes used in preparing the enzyme syrup.

[0030] Specifically, α-amylase with an enzyme activity of 1500-2500 U / g extracted by Bacillus licheniformis, amyloglucosidase with an enzyme activity of 1400-2000 U / g extracted by Aspergillus niger, and α-amylase with an enzyme activity of 1200-1700 U / g extracted by Bacillus liquefactionus are mixed and stirred to form a homogeneous enzyme slurry.

[0031] S2: Grind tiger nuts into a paste to prepare raw pulp.

[0032] In step S2, grinding tiger nuts into a pulp to prepare raw pulp includes:

[0033] Grind the tiger nuts and pass them through a 200-mesh sieve;

[0034] Take the sieved material, add water, and wet grind it to produce raw pulp with a fineness of 300 mesh.

[0035] Specifically, tiger nuts are ground into a fine powder, which is then passed through a 200-mesh sieve. The sieve-passing material is collected to obtain tiger nut powder with a particle size of less than 200 mesh. An appropriate amount of purified water is then added to the tiger nut powder and stirred to ensure thorough mixing. Wet ultrafine grinding is then performed in an aqueous environment (i.e., under the condition that the tiger nut powder and water are mixed), further grinding the tiger nut powder mixed in the water until a raw tiger nut paste with a fineness of 300 mesh is obtained. In this embodiment, the fineness of the raw tiger nut paste can be detected by sieving the paste or controlled by adjusting the operating parameters of the grinding equipment.

[0036] S3: Mix the enzyme syrup and raw pulp in a predetermined ratio and then perform enzymatic hydrolysis.

[0037] In this embodiment, to prepare tiger nut liquid, the enzyme syrup and raw pulp are mixed in a weight ratio of 5-15 parts tiger nuts, 1 part enzyme syrup, and 30-70 parts water. Preferably, the enzyme syrup is added to a container for holding the raw pulp, and the mixture is stirred to ensure thorough mixing. This allows the enzymes in the enzyme syrup to come into contact with the raw pulp, hydrolyzing macromolecules in the raw pulp and simultaneously enzymatically breaking down the tiger nut particles, thereby reducing the amount of sediment in the enzymatic hydrolysis product.

[0038] In this embodiment, the enzymatic hydrolysis temperature was 60–80°C. This temperature increase accelerated the enzymatic hydrolysis reaction rate while preventing enzyme denaturation and inactivation due to excessively high temperatures, thus maintaining enzyme activity. The hydrolysis time was 0.5–1.5 hours to ensure complete hydrolysis of macromolecules and tiger nut particles in the raw hydrolysate. Measurements showed that the sediment content of the hydrolysis product was less than 2.39%, significantly improving the taste of the tiger nut liquid.

[0039] S4: Homogenize the enzymatic hydrolysis product under pressure, add ingredients and filter to obtain soybean liquid slurry.

[0040] Specifically, an appropriate amount of purified water is added to the enzymatic hydrolysis product, mixed, and homogenized under pressure. Then, the ingredients are added and the mixture is brought to a final volume with water, homogenized again under pressure, and filtered. In this embodiment, the amount of purified water added to the enzymatic hydrolysis product is such that the enzymatic hydrolysis product forms a dilute solution in the purified water, and the liquid portion of this dilute solution can easily pass through the pressure homogenizer. For example, the ratio of enzymatic hydrolysis product to purified water is 1:2 to 1:10. Of course, the ratio can be further adjusted according to the processing conditions.

[0041] The soybean liquid raw slurry of this embodiment includes the following components in parts by weight: 5-15 parts tiger nut powder, 1 part enzyme syrup, 30-70 parts water, 0-2 parts soybean protein, and 0-2 parts calcium carbonate.

[0042] S5: Sterilize and inactivate enzymes in the soybean liquid raw pulp to obtain tiger pea liquid.

[0043] Specifically, the soybean pulp is subjected to ultra-high temperature sterilization and enzyme inactivation to obtain tiger nut liquid with a reducing sugar content of 15% and a protein hydrolysis degree of 6.95%. This liquid is then aseptically packaged to obtain tiger nut products of the corresponding specifications. In this embodiment, the sterilization and enzyme inactivation operations are performed using an ultra-high temperature sterilizer, a steam exchanger, or a heat exchanger. The sterilization and enzyme inactivation operation lasts for at least 15 seconds, and the minimum sterilization and enzyme inactivation temperature is 118°C. By providing high-temperature conditions, the enzymes and other microorganisms in the soybean pulp are denatured and inactivated, preventing the enzymes and microorganisms from continuing to multiply or die in the nutrient environment of the soybean pulp, thus avoiding problems such as off-flavor and sedimentation in the tiger nut liquid, and ensuring the quality of the tiger nut liquid.

[0044] This invention also discloses a tiger nut liquid prepared by the above-mentioned method. Nutritional tests on the tiger nut liquid prepared by the above method show that the reducing sugar content is 15% and the degree of protein hydrolysis is 6.95%, which meets the drinking requirements. Compared with milk and other plant milk, tiger nut liquid prepared by enzymatic method has a higher reducing sugar content, so no additional sugar needs to be added. It is beneficial for the prevention and treatment of metabolic syndromes such as diabetes, glycogen storage disease, and obesity.

[0045] The preparation process of tiger nut liquid will be explained below with specific examples.

[0046] Prepare the raw materials according to the following proportions by weight:

[0047] 5-15 parts tiger nuts, 1 part enzyme syrup, 30-70 parts water, 0-2 parts soy protein, 0-2 parts calcium carbonate.

[0048] Example 1

[0049] In this embodiment, the raw materials are prepared according to the following ratio: 10 parts tiger nuts, 1 part enzyme syrup, 50 parts water, 0-2 parts soy protein, and 0-2 parts calcium carbonate. The enzyme syrup is composed of α-amylase with an enzyme activity of 1500-2500 U / g extracted by Bacillus licheniformis, amyloglucosidase with an enzyme activity of 1400-2000 U / g extracted by Aspergillus niger, and α-amylase with an enzyme activity of 1200-1700 U / g extracted by Bacillus liquefactionus.

[0050] Ten parts of tiger nuts were added to purified water containing 0.25% sodium bicarbonate at 30°C and wet-milled at 6000 RPM to obtain tiger nut milk with a fineness of 300 mesh. One part of enzyme syrup was added and heated to 70°C for 50 minutes for enzymatic hydrolysis. The mixture was then made up to 34 parts of water and homogenized under pressure at 30 MPa. 0-2 parts of soy protein and 0-2 parts of calcium carbonate were added, and the mixture was homogenized again under pressure at 30 MPa. After volume adjustment, homogenization, filtration, and ultra-high temperature instantaneous sterilization, a tiger nut liquid with a reducing sugar content of 15% and a protein hydrolysis degree of 6.95% was obtained. This liquid was then aseptically packaged to obtain the tiger nut product of the corresponding specifications. In actual operation, the amount of soy protein and calcium carbonate added can be adjusted according to the flavor and nutritional requirements of the beverage. Calcium carbonate is used for flavoring.

[0051] In other embodiments, the amounts of tiger nuts, enzyme syrup, and water added can be adjusted as needed.

[0052] Enzymatic digestion test

[0053] To illustrate the enzymatic hydrolysis effect of the present invention, an enzymatic hydrolysis experiment was conducted, divided into four groups: Group 1, Group 2, Group 3, and Control Group. Group 1 was tiger nut liquid prepared by enzymatic hydrolysis using the method of Example 1 of the present invention; Group 2 was tiger nut liquid prepared by enzymatic hydrolysis, wherein the enzyme solution consisted of α-amylase extracted from Bacillus licheniformis and α-amylase extracted from Bacillus liquefactionus; Group 3 was tiger nut liquid prepared by enzymatic hydrolysis, wherein the enzyme solution consisted of amyloglucosidase extracted from Aspergillus niger; and the Control Group was tiger nut liquid not prepared by enzymatic hydrolysis, the steps of which were the same as those in Example 1 except that no enzyme syrup was added. After the preparation of the four groups, the degree of protein hydrolysis, reducing sugar content, and residue content in the enzymatic hydrolysate were measured for each group.

[0054] To compare the enzymatic hydrolysis effects of the three groups in preparing tiger nut liquid using the enzymatic method, the enzyme activity content of the enzyme solutions in groups 1, 2, and 3 was the same.

[0055] The hydrolyzed protein content was tested using the biuret test.

[0056] The reducing sugar content was determined by potassium permanganate titration, according to the second method of the national food safety standard GB5009.7.

[0057] The method for testing residue content is as follows: Weigh the filter paper to an accuracy of 0.001g. Take a 10.5g sample and filter it using the filter paper (pore size 200 µm). Dry the filter paper in a dehydrator at 60°C for 3 days. Remove the filter paper and weigh it to an accuracy of 0.001g. Calculate the weight difference of the filter paper before and after filtration, and divide it by the sample weight of 10.5g to obtain the percentage of residue content.

[0058] The test results are shown in the table below:

[0059]

[0060] Therefore, the soybean liquid obtained by enzymatic hydrolysis of raw tiger pea pulp using the enzyme syrup containing three enzymes of the present invention has a reducing sugar content of 15% and a protein hydrolysis degree of 6.95%. The reducing sugar concentration is significantly higher than that of the control group and the reducing sugar concentration when using one or two enzymes to hydrolyze tiger peas. Moreover, while meeting the protein requirements for drinking, the amount of sediment is significantly reduced. The tiger pea liquid retains the nutritional components and flavor of tiger peas, while increasing the degree of protein hydrolysis, making it easier for the body to digest and absorb. After sterilization and enzyme inactivation, it can be consumed directly, avoiding the side effects such as bloating and diarrhea caused by drinking milk or pure soy milk in people with indigestion, belching, or poor gastrointestinal function. The amount of sediment is low, and the finished product has a smooth taste.

[0061] The method for preparing tiger nut liquid according to the present invention involves preparing an enzyme syrup. The enzyme syrup hydrolyzes the raw tiger nut pulp, releasing the nutrients and sugars in the raw tiger nut pulp, thereby enhancing the nutritional value of the tiger nut liquid. At the same time, it decomposes the large molecules in the tiger nut, avoiding the problems of turbidity and browning caused by the precipitation or deterioration of large molecules, improving the stability of the product, and preventing the loss of nutrients. After enzymatic hydrolysis, the residue in the raw tiger nut pulp is further decomposed, reducing the amount of residue in the enzymatic hydrolysis products, thereby improving the flavor and taste of the tiger nut liquid.

[0062] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0063] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for preparing tiger nut liquid, characterized in that, Includes the following steps: Prepare enzyme syrup; Tiger nuts are ground into a paste to prepare raw pulp; The enzyme syrup and raw pulp are mixed in a predetermined ratio and then enzymatically hydrolyzed. The enzymatic hydrolysis product is homogenized under pressure, then the ingredients are added and filtered to obtain soybean liquid slurry; Sterilize and inactivate the enzymes in the soybean liquid raw pulp to obtain tiger pea liquid; The enzyme syrup is a mixture of α-amylase extracted from Bacillus licheniformis, amyloglucosidase extracted from Aspergillus niger, and α-amylase extracted from Bacillus liquefactionus.

2. The preparation method according to claim 1, characterized in that, The enzyme activity of α-amylase extracted from Bacillus licheniformis is 1500-2500 U / g, the enzyme activity of amyloglucosidase extracted from Aspergillus niger is 1400-2000 U / g, and the enzyme activity of α-amylase extracted from Bacillus liquefactionus is 1200-1700 U / g.

3. The preparation method according to claim 2, characterized in that, The raw materials for the soybean liquid slurry include the following components in parts by weight: 5-15 parts tiger nut powder, 1 part enzyme syrup, 30-70 parts water, 0-2 parts soybean protein, and 0-2 parts calcium carbonate.

4. The preparation method according to claim 3, characterized in that, The process of grinding tiger nuts to prepare raw pulp includes: Grind the tiger nuts and pass them through a 200-mesh sieve; Take the sieved material, add water, and wet grind it to produce raw pulp with a fineness of 300 mesh.

5. The preparation method according to claim 4, characterized in that, The enzymatic hydrolysis temperature is 60–80°C, and the enzymatic hydrolysis time is 0.5–1.5 h.

6. The preparation method according to claim 5, characterized in that, The equipment used for sterilization and enzyme inactivation is an ultra-high temperature sterilizer or a heat exchanger.

7. The preparation method according to claim 6, characterized in that, The equipment used for sterilization and enzyme inactivation is a steam exchanger.

8. The preparation method according to claim 6, characterized in that, The sterilization and enzyme inactivation process lasts for at least 15 seconds, and the minimum sterilization and enzyme inactivation temperature is 118°C.

9. The preparation method according to claim 8, characterized in that, The amount of sediment in the enzymatic hydrolysis product is less than 2.39%.

10. A tiger nut liquid, characterized in that, The tiger nuts liquid is prepared by any one of the preparation methods described in claims 1 to 9, and has a reducing sugar content of 15% and a protein hydrolysis degree of 6.95%.

Images