A method for defatting mealworm larvae protein-assisted defatting without organic solvent residue

Abstract

This invention provides a method for defatting mealworm larvae protein with no organic solvent residue, belonging to the field of food processing technology. The method involves directly grinding mealworm larvae after liquid nitrogen freezing, followed by irradiation-assisted protein extraction. The resulting mealworm larvae protein has a fat content ≤5.49% and an emulsifying activity ≥58.90 mg / L. 2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%. The method used in this invention not only avoids the use of organic solvents, but also significantly improves protein extraction efficiency, enhances the emulsification properties and oxidative stability of proteins, and improves their digestibility.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and in particular to a method for defatting mealworm larvae protein-assisted defatting without organic solvent residue. Background Technology

[0002] As is well known, with the rapid growth of the global population, the demand for food will become a formidable challenge. In particular, the demand for animal protein, mainly meat products, is increasing, projected to rise by 200 million tons annually by 2050. Therefore, finding new protein resources will become crucial.

[0003] Over the past decade, edible insects have gained increasing attention as a sustainable protein source in the food industry's ingredient supply chain. Their high breeding density, ease of survival, and relatively low environmental impact compared to other animals suggest significant potential in addressing the food crisis. Furthermore, research has revealed the high nutritional value of edible insects, with their protein containing essential amino acids, as well as abundant unsaturated fatty acids, vitamins, and minerals. Despite these advantages, the application of edible insects faces a significant challenge: low consumer acceptance of whole edible insects. Current research indicates that processing edible insects into insect powder or protein powder for use in food can greatly improve consumer acceptance. However, the presence of unsaturated fatty acids and chitin may reduce the oxidative stability and digestibility of foods containing insect powder. Therefore, refining edible insect protein will be a crucial step in the application of edible insects.

[0004] Traditional extraction of edible insect protein generally involves five steps: edible insect drying, defatting, protein dissolution and recovery, protein purification, and protein drying. However, a crucial step in protein separation is the defatting process. A common method is defatting with organic solvents. Due to the different polarities, selectivities, and effects on protein denaturation of different solvents, defatted protein powders exhibit varying physical, chemical, and functional properties. Currently, the most common defatting method uses hexane as the defatting solvent. However, while hexane, as an inert organic solvent, does not denature proteins, it suffers from low defatting rates when fats are tightly bound to proteins. Studies have found that edible insect protein defatted with hexane still retains 9%–13% fat residue. Although hexane is the most commonly used defatting solvent in the food industry, its low defatting efficiency and high usage remain problems. These drawbacks necessitate the search for novel auxiliary defatting methods. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide a method for defatting mealworm larvae protein without organic solvent residue. The method for defatting mealworm larvae protein provided by this invention does not use organic solvents, the finished mealworm larvae protein product has no organic solvent residue, and improves the fat removal efficiency and improves the protein functional properties.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for defatting mealworm eggs and larvae without organic solvent residue, comprising the following steps:

[0008] S1. Pretreatment of mealworm larvae: Mealworm larvae are passed through a 20-mesh sieve to remove impurities, frozen in liquid nitrogen, and then ground into powder to obtain mealworm larvae powder.

[0009] S2. Disperse the mealworm larvae powder in distilled water, add sodium bisulfite, and stir at 400 rpm to 600 rpm for 1 min to 2 min to obtain a mealworm larvae powder suspension.

[0010] S3. Adjust the pH of the mealworm larvae suspension to 10.0 with 1 mol / L NaOH, stir at 400 rpm to 600 rpm for 0.5 to 1.5 hours, and then use... 60 Irradiate with Co-γ rays, centrifuge, and collect the supernatant;

[0011] S4. Adjust the pH of the supernatant to 4.3-4.5 with 1 mol / L HCl, incubate at room temperature, centrifuge at low temperature, and collect the precipitate;

[0012] S5. Take the precipitate obtained in S4, dissolve it in distilled water, adjust the pH value to 7.0 with 1 mol / L NaOH, dialyze, freeze dry, grind and sieve to obtain yellow mealworm larvae protein without organic solvent residue.

[0013] Preferably, the w / v ratio of mealworm larvae powder to distilled water in S2 is 1:3.

[0014] Preferably, the amount of sodium bisulfite added in S2 is 0.4g to 0.6g of sodium bisulfite per kg of mealworm larvae powder.

[0015] Preferably, the irradiation dose in S3 is 10 kGy, the dose rate is 1.8 kGy / h, the irradiation time is 20 s, and the irradiation temperature is 45 °C.

[0016] Preferably, the centrifugation in S3 is 5000g for 8 to 12 minutes.

[0017] Preferably, the low-temperature centrifugation in S4 is 4°C, 5000g, for 15 to 25 minutes.

[0018] Preferably, the ratio of the amount of distilled water added in step S5 to the w / v ratio of the precipitate in step S5 is 1:3.

[0019] Preferably, in step S5, dialysis is performed at 4°C using a dialysis bag with a molecular weight cutoff of 1000 Da for 22 to 26 hours.

[0020] The present invention also provides a method for preparing mealworm larvae protein by means of defatting mealworm larvae protein without organic solvent residue as described in the above technical solution.

[0021] Preferably, the fat content of the mealworm larvae protein is ≤5.49%; and the emulsifying activity is ≥58.90 mg / L. 2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%.

[0022] Beneficial Technical Effects: This invention provides a method for defatting mealworm larvae protein without organic solvent residue. The method involves directly grinding mealworm larvae after liquid nitrogen freezing, followed by irradiation-assisted protein extraction. The resulting mealworm larvae protein has a fat content ≤5.49% and an emulsifying activity ≥58.90 mg / L. 2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%. The method used in this invention not only avoids the use of organic solvents, but also significantly improves protein extraction efficiency, enhances the emulsification properties and oxidative stability of proteins, and improves their digestibility. Attached Figure Description

[0023] Figure 1 The effect of irradiation time on the protein and fat content of mealworm larvae;

[0024] Figure 2 The effect of irradiation temperature on the protein and fat content of mealworm larvae;

[0025] Figure 3 The effect of irradiation dose on the protein and fat content of mealworm larvae;

[0026] Figure 4 The effect of irradiation dose on the protein solubility of yellow mealworm larvae;

[0027] Figure 5 The effect of irradiation dose on the protein emulsification properties of yellow mealworm larvae;

[0028] Figure 6 The effect of irradiation dose on the protein digestibility of mealworm larvae. Detailed Implementation

[0029] This invention provides a method for defatting mealworm larvae proteins without organic solvent residue, comprising the following steps:

[0030] S1. Pretreatment of mealworm larvae: Mealworm larvae are passed through a 20-mesh sieve to remove impurities, frozen in liquid nitrogen, and then ground into powder to obtain mealworm larvae powder.

[0031] S2. Disperse the mealworm larvae powder in distilled water, add sodium bisulfite, and stir at 400 rpm to 600 rpm for 1 min to 2 min to obtain a mealworm larvae powder suspension.

[0032] S3. Adjust the pH of the mealworm larvae suspension to 10.0 with 1 mol / L NaOH, stir at 400 rpm to 600 rpm for 0.5 to 1.5 hours, and then use... 60 Irradiate with Co-γ rays, centrifuge, and collect the supernatant;

[0033] S4. Adjust the pH of the supernatant to 4.3-4.5 with 1 mol / L HCl, incubate at room temperature, centrifuge at low temperature, and collect the precipitate;

[0034] S5. Take the precipitate obtained in S4, dissolve it in distilled water, adjust the pH value to 7.0 with 1 mol / L NaOH, dialyze, freeze dry, grind and sieve to obtain yellow mealworm larvae protein without organic solvent residue.

[0035] The present invention first pre-treats the mealworm larvae: the mealworm larvae are passed through a 20-mesh sieve to remove impurities, frozen in liquid nitrogen, and then ground into powder to obtain mealworm larvae powder.

[0036] In this invention, the mealworm larvae are mealworms that have been cultured for 80 to 100 days, with a body length of 1.5 cm to 2.5 cm and a weight of 0.4 g to 0.6 g; the impurity removal refers to removing feed residue from the mealworm larvae; the liquid nitrogen freezing can directly kill the mealworm larvae; this invention chooses to freeze the mealworms with liquid nitrogen without drying, and directly grinds the mealworm larvae to extract protein, which is faster, simpler, and saves energy.

[0037] The present invention disperses yellow mealworm larvae powder in distilled water, adds sodium bisulfite, and stirs at 400 rpm to 600 rpm for 1 min to 2 min to obtain a yellow mealworm larvae powder suspension.

[0038] In this invention, the w / v ratio of the mealworm larvae powder to distilled water is preferably 1:3; the amount of sodium bisulfite added is preferably 0.4g to 0.6g per kg of mealworm larvae powder, more preferably 0.5g per kg of mealworm larvae powder; the stirring is preferably performed at 500 rpm for 1 min. The sodium bisulfite described in this invention can prevent enzymatic browning that may occur during the extraction of mealworm larvae protein, thus ensuring the properties of the mealworm larvae protein.

[0039] In this invention, the pH of the mealworm larvae suspension was adjusted to 10.0 using 1 mol / L NaOH, and after stirring at 400 rpm to 600 rpm for 0.5 to 1.5 hours, it was then used. 60 Irradiate with Co-γ rays, centrifuge, and collect the supernatant.

[0040] In this invention, the preferred irradiation dose is 10 kGy, the dose rate is 1.8 kGy / h, the irradiation time is 20 s, and the irradiation temperature is 45°C; the preferred centrifugation is 5000g for 8-12 min, more preferably 5000g for 10 min. This invention, by using irradiation assistance and setting specific parameters for irradiation assistance, along with other operations, avoids the use of organic solvents in protein defatting, while significantly improving protein extraction efficiency and enhancing protein functional properties. Furthermore, by adjusting the pH of the mealworm larvae suspension to 10.0, this invention ensures maximum solubility of mealworm larvae protein and prevents denaturation of the vast majority of the protein.

[0041] In this invention, the pH of the supernatant was adjusted to 4.3-4.5 with 1 mol / L HCl, incubated at room temperature, centrifuged at low temperature, and the precipitate was collected.

[0042] In this invention, the low-temperature centrifugation is preferably performed at 4°C and 5000g for 15-25 minutes, more preferably at 4°C and 5000g for 20 minutes. The incubation time is preferably 0.5-1.5 hours, more preferably 1-1.5 hours. The incubation in this invention allows for sufficient precipitation of proteins in the supernatant.

[0043] The present invention takes the above-obtained precipitate, dissolves it in distilled water, adjusts the pH value to 7.0 with 1 mol / L NaOH, dialyzes, freeze-dries, grinds and sieves to obtain yellow mealworm larvae protein without organic solvent residue.

[0044] In this invention, the amount of distilled water added is preferably at a w / v ratio of 1:3 to the precipitate; the dialysis is preferably performed at 4°C using a dialysis bag with a molecular weight cutoff of 1000 Da for 22-26 hours, more preferably 24 hours; the freeze-drying and grinding can be performed using conventional methods in the art, and the sieving is preferably performed through a 50-mesh sieve. Adjusting the pH to 7.0 in this invention makes the final mealworm larvae protein more suitable for indicator determination and subsequent application in products.

[0045] The present invention also provides a method for preparing mealworm larvae protein by means of defatting mealworm larvae protein without organic solvent residue as described in the above technical solution.

[0046] In this invention, the fat content of the mealworm larvae protein is ≤5.49%; the emulsifying activity is ≥58.90 mg / L.2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%.

[0047] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments. Unless otherwise specified, the materials, reagents, etc., used in the embodiments and experimental examples of the present invention can be obtained commercially; unless otherwise specified, the methods used in the embodiments and experimental examples of the present invention are conventional methods.

[0048] Example 1

[0049] (1) Pretreatment of mealworm larvae: Feed residue and impurities were separated from live mealworm larvae by passing them through a 20-mesh sieve. All larvae were from the same batch and were killed by direct freezing with liquid nitrogen, then ground into powder. The insect powder was dispersed in distilled water at a ratio of 1:3 (w / v). Then, sodium bisulfite (0.5 g / kg, dry weight of insects) was added and stirred at 500 rpm for 1 min.

[0050] (2) Adjust the pH of the suspension to 10.0 with 1 mol / L NaOH, stir at 500 rpm for 1 h, and then pass the suspension through... 60 The Co-γ ray irradiation treatment was carried out with an irradiation dose of 10 kGy, a dose rate of 1.8 kGy / h, an irradiation time of 20 s, and an irradiation temperature of 45 ℃. Then, the mixture was centrifuged at 5000 g for 10 min to obtain the supernatant and precipitate.

[0051] (4) The collected supernatant was adjusted to the isoelectric point (pI, pH = 4.30-4.50) with 1 mol / L HCl, incubated at room temperature (25℃) for 1 h, and then centrifuged at 4℃ and 5000g for 20 min to separate fat and protein.

[0052] (5) Collect the obtained protein precipitate, dissolve it in distilled water, and adjust the pH to 7.0 with 1 mol / L NaOH;

[0053] (6) The obtained protein solution was dialyzed at 4°C for 24 h using a dialysis bag with a molecular weight cutoff of 1000 Da, and then freeze-dried.

[0054] (7) The freeze-dried mealworm larvae protein was passed through a 50-mesh sieve after being ground in a coffee grinder to obtain refined mealworm larvae protein.

[0055] Example 2

[0056] (1) Pretreatment of mealworm larvae: Feed residue and impurities were separated from live mealworm larvae by passing them through a 20-mesh sieve. All larvae were from the same batch and were killed by direct freezing with liquid nitrogen, then ground into powder. The insect powder was dispersed in distilled water at a ratio of 1:3 (w / v). Then, sodium bisulfite (0.5 g / kg, dry weight of insects) was added and stirred at 400 rpm for 2 min.

[0057] (2) Adjust the pH of the suspension to 10.0 with 1 mol / L NaOH, stir at 400 rpm for 1.5 h, and then pass the suspension through... 60 The Co-γ ray irradiation treatment was carried out with an irradiation dose of 10 kGy, a dose rate of 1.8 kGy / h, an irradiation time of 20 s, and an irradiation temperature of 45 ℃. Then, the mixture was centrifuged at 5000 g for 8 min to obtain the supernatant and precipitate.

[0058] (4) The collected supernatant was adjusted to the isoelectric point (pI, pH = 4.30-4.50) with 1 mol / L HCl, incubated at room temperature (25℃) for 1.5 h, and then centrifuged at 4℃ and 5000g for 15 min to separate fat and protein.

[0059] (5) Collect the obtained protein precipitate, dissolve it in distilled water, and adjust the pH to 7.0 with 1 mol / L NaOH;

[0060] (6) The obtained protein solution was dialyzed at 4°C for 26 h using a dialysis bag with a molecular weight cutoff of 1000 Da, and then freeze-dried.

[0061] (7) The freeze-dried mealworm larvae protein was passed through a 50-mesh sieve after being ground in a coffee grinder to obtain refined mealworm larvae protein.

[0062] Example 3

[0063] (1) Pretreatment of mealworm larvae: Feed residue and impurities were separated from live mealworm larvae by passing them through a 20-mesh sieve. All larvae were from the same batch and were killed by direct freezing with liquid nitrogen, then ground into powder. The insect powder was dispersed in distilled water at a ratio of 1:3 (w / v). Then, sodium bisulfite (0.5 g / kg, dry weight of insects) was added and stirred at 600 rpm for 1 min.

[0064] (2) Adjust the pH of the suspension to 10.0 with 1 mol / L NaOH, stir at 600 rpm for 0.5 h, and then pass the suspension through... 60 The Co-γ ray irradiation treatment was carried out with an irradiation dose of 10 kGy, a dose rate of 1.8 kGy / h, an irradiation time of 20 s, and an irradiation temperature of 45 ℃. Then, the mixture was centrifuged at 5000 g for 12 min to obtain the supernatant and precipitate.

[0065] (4) The collected supernatant was adjusted to the isoelectric point (pI, pH = 4.30-4.50) with 1 mol / L HCl, incubated at room temperature (25℃) for 0.5 h, and then centrifuged at 4℃ and 5000g for 25 min to separate fat and protein.

[0066] (5) Collect the obtained protein precipitate, dissolve it in distilled water, and adjust the pH to 7.0 with 1 mol / L NaOH;

[0067] (6) The obtained protein solution was dialyzed at 4°C for 22 h using a dialysis bag with a molecular weight cutoff of 1000 Da, and then freeze-dried.

[0068] (7) The freeze-dried mealworm larvae protein was passed through a 50-mesh sieve after being ground in a coffee grinder to obtain refined mealworm larvae protein.

[0069] Comparative Example 1

[0070] The difference from Example 1 is that Comparative Example 1 omitted the irradiation treatment to obtain mealworm larvae protein, which was then defatted with n-hexane. The specific steps are as follows: the freeze-dried mealworm larvae protein was dispersed in n-hexane at a mass-to-volume ratio of 1:10 (w / v), stirred at 500 rpm for 1 h, and then centrifuged at 3000 g for 20 min at 4 °C to remove fat; this step was repeated 4 times; the obtained mealworm larvae protein was placed in a fume hood overnight to remove residual n-hexane.

[0071] Comparative Examples 2-5

[0072] The difference from Example 1 is that the irradiation dose in Comparative Examples 2 to 5 was set to 0 kGy, 5 kGy, 15 kGy and 20 kGy respectively, while the other operations were the same as in Example 1.

[0073] Comparative Examples 6-10

[0074] The difference from Example 1 is that the irradiation time in Comparative Examples 6 to 10 was set to 0s, 5s, 10s, 15s, and 25s, respectively, while the other operations were the same as in Example 1.

[0075] Comparative Examples 11–13

[0076] The difference from Example 1 is that the irradiation temperature in Comparative Examples 11 to 13 was set to 25°C, 35°C, and 55°C, respectively, while the other operations were the same as in Example 1.

[0077] Test Example 1

[0078] The mealworm larvae proteins obtained in Examples 1-3 were used to determine their fat content, emulsification properties, and digestibility. The fat content was determined according to GB5009.6-2016.

[0079] The steps for testing emulsification properties are as follows:

[0080] Emulsion preparation: 9.0 mL of a 10 mg / mL mealworm larvae protein solution and 1.0 mL of soybean oil were added to a 50 mL centrifuge tube, and homogenized at 13,500 rpm for 2 min. Immediately afterwards, 50 μL of the emulsion was taken from the bottom 0.5 cm of the centrifuge tube and diluted with 4.95 mL of a 0.1% (w / v) sodium dodecyl sulfate (SDS) solution. The absorbance of the diluted solution at 500 nm was measured using a spectrophotometer. Emulsifying activity (m 2 The calculations for (g) and emulsion stability (%) are as follows:

[0081]

[0082]

[0083] Where A 10 A0 and A10 represent the absorbance at 500 nm at 10 min and 0 min, respectively. C is the protein concentration (mg / mL). denoted as the volume fraction of the oil phase in the emulsion, L as the optical path length (a cuvette with an optical path length of 1 cm was used in this experiment), and D as the dilution factor.

[0084] The steps for detecting digestibility are as follows:

[0085] A TMP solution (40 mg / mL, pH = 2.0) was mixed with simulated gastric fluid (SGF) containing 0.5 M KCl, 0.5 M KH₂PO₄, 1 M NaHCO₃, 2 M NaCl, 0.15 M MgCl₂(H₂O)₆, 0.5 M (NH₄)₂CO₃, 0.3 M CaCl₂, and 480 U / mL pepsin (pH = 3) at a volume ratio of 1:1. The mixture was then digested at 37 °C with continuous shaking (200 rpm) for 2 h. The reaction was stopped by adjusting the pH to 7. Subsequently, 20 mL of gastric digestion fluid was mixed with 20 mL of simulated intestinal fluid (SIF), containing 0.5 M KCl, 0.5 M KH₂PO₄, 1 M NaHCO₃, 2 M NaCl, 0.15 M MgCl₂(H₂O)₆, 0.3 M CaCl₂, and 19740 U / mL trypsin (pH = 7.0). Digestion was carried out at 37 °C for 2 h, and the reaction was terminated by water bath at 95 °C for 5 min. Undigested proteins in the gastric and intestinal digestion products were precipitated by adding 15% trichloroacetic acid (1:1 volume ratio to digestion products). After centrifugation at 10000 g for 15 min, the protein digestibility was calculated as follows:

[0086]

[0087] Where W0 is the protein content of the blank group protease (mg), W1 is the protein content of the sample before digestion (mg), and W2 is the protein content of the supernatant (mg).

[0088] The fat content of the mealworm larvae protein obtained in Examples 1-3 was found to be 5.06±0.04%, 5.26±0.26%, and 5.20±0.29%, respectively; the emulsifying activity was 60.29±0.15 mg / L, respectively. 2 / g, 59.50±0.57m 2 / g, 59.55±0.65m 2 / g, the emulsification stability was 73.74±0.31%, 73.45±0.58%, and 73.60±0.38%, respectively; the digestibility was 76.54±0.26%, 76.36±0.55%, and 76.33±0.44%, respectively.

[0089] Test Example 2

[0090] The protein from mealworm larvae obtained in Example 1 and Comparative Examples 1-13 was analyzed for fat content according to GB5009.6-2016. The results are as follows: Figures 1-3 As shown.

[0091] Depend on Figure 1 It can be seen that with the increase of irradiation time, the protein and fat content of mealworm larvae first decreased and then increased (P<0.05). However, the fat content was lower than that of the unirradiated treatment group. Furthermore, the protein and fat content was lowest at an irradiation time of 20s, and there was no significant difference from the hexane defatting treatment group (P>0.05).

[0092] Depend on Figure 2 It can be seen that under irradiation-assisted defatting conditions, the protein and fat content was lowest at an irradiation temperature of 45℃ compared to room temperature (P<0.05). This indicates that a suitable temperature is conducive to fat dissolution. Furthermore, under irradiation conditions, the fat content at temperatures of 45℃ and 55℃ was not significantly different from that of the hexane defatting group (P>0.05).

[0093] Depend on Figure 3 It can be seen that with the increase of irradiation dose, the protein and fat content of mealworm larvae first decreased and then increased (P<0.05), but both were lower than those of the unirradiated treatment group, and the defatting effect was similar to that of n-hexane at an irradiation dose of 10 kGy (P>0.05).

[0094] Experimental Example 3

[0095] The mealworm larvae proteins obtained in Example 1 and Comparative Examples 1-6 were tested for their solubility, emulsifying properties, and digestibility. The test results are as follows: Figures 4-6 As shown.

[0096] Depend on Figure 4 It can be seen that, compared with the unirradiated group, the solubility of the irradiated protein was significantly increased (P<0.05), and the solubility reached 73.21±0.66% at an irradiation dose of 10 kGy.

[0097] Depend on Figure 5 It can be seen that, compared with the unirradiated sample, the protein emulsifying activity and emulsifying stability of the irradiated sample were significantly improved (P<0.05), and the emulsifying properties were the best when the irradiation dose was 10 kGy.

[0098] Depend on Figure 6 It can be seen that with increasing irradiation dose, the digestibility of mealworm larvae protein first increases and then decreases. Furthermore, the protein digestibility is highest at an irradiation dose of 10 kGy (P < 0.05).

[0099] In summary, the fat content of the mealworm larvae protein obtained by this invention is ≤5.49%; the emulsifying activity is ≥58.90 mg / L. 2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%. The method used in this invention not only avoids the use of organic solvents, but also significantly improves protein extraction efficiency, enhances protein oxidative stability, and improves its digestibility.

[0100] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for defatting mealworm larvae protein-assisted defatting without organic solvent residue, characterized in that, Includes the following steps: S1. Pretreatment of mealworm larvae: Mealworm larvae are passed through a 20-mesh sieve to remove impurities, frozen in liquid nitrogen, and then ground into powder to obtain mealworm larvae powder. S2. Disperse the mealworm larvae powder in distilled water, add sodium bisulfite, and stir at 400 rpm to 600 rpm for 1 to 2 minutes to obtain a mealworm larvae powder suspension; the w / v ratio of the mealworm larvae powder to the distilled water in S2 is 1:3; the amount of sodium bisulfite added in S2 is 0.4 g to 0.6 g of sodium bisulfite per kg of mealworm larvae powder. S3. Adjust the pH of the mealworm larvae suspension to 10.0 with 1 mol / L NaOH, stir at 400 rpm to 600 rpm for 0.5 h to 1.5 h, then irradiate with 60Co-γ rays, centrifuge, and collect the supernatant; the irradiation dose in S3 is 10 kGy, the dose rate is 1.8 kGy / h, the irradiation time is 20 s, and the irradiation temperature is 45℃; the centrifugation in S3 is 5000g for 8 min to 12 min. S4. Adjust the pH of the supernatant to 4.3-4.5 with 1 mol / L HCl, incubate at room temperature, centrifuge at low temperature, and collect the precipitate; the low-temperature centrifugation in S4 is 4℃, 5000g for 15-25 min. S5. Take the precipitate obtained in S4, dissolve it in distilled water, adjust the pH to 7.0 with 1 mol / L NaOH, dialyze, freeze-dry, grind, and sieve to obtain mealworm larvae protein without organic solvent residue; the w / v ratio of the amount of distilled water added in S5 to the precipitate in S5 is 1:3; the dialysis in S5 is performed at 4°C using a dialysis bag with a molecular weight cutoff of 1000 Da for 22h to 26h. The protein from the mealworm larvae has a fat content ≤5.49% and an emulsifying activity ≥58.90 mg / L. 2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%.

2. The mealworm larvae protein prepared by the method of defatting mealworm larvae protein without organic solvent residue as described in claim 1.

3. The mealworm larvae protein according to claim 2, characterized in that, The protein from the mealworm larvae has a fat content ≤5.49% and an emulsifying activity ≥58.90 mg / L. 2 / g, emulsification stability ≥73.22%; digestibility ≥75.81%.

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