CN-116254312-B - Multifunctional pea polypeptide and preparation method thereof

Abstract

The invention discloses a multifunctional pea polypeptide and a preparation method thereof, belonging to the technical field of functional polypeptides; the method comprises the steps of extracting pea protein isolate by utilizing an ultrasonic-assisted alkali dissolution and acid precipitation method, preparing pea polypeptide by utilizing a steam explosion technology-assisted enzymolysis method, and evaluating the functional activity of the pea polypeptide by utilizing a chemical method. The pea polypeptide prepared by the method has the functions of resisting oxidation, reducing blood pressure and reducing blood sugar, the pea polypeptide is obtained by adopting the steam explosion treatment to assist enzymolysis, the functions of the pea polypeptide are improved, the DPPH free radical scavenging capacity is 92%, the ABTS free radical scavenging capacity is 93%, the O 2 ‑ free radical scavenging capacity is 98%, the ACE (angiotensin-converting enzyme) activity inhibition rate is 68%, the alpha-glucosidase activity inhibition rate is 75%, and the alpha-amylase activity inhibition rate is 71%, and a foundation is laid for the pea polypeptide to be widely applied to functional foods or special meal foods.

Inventors

• SONG LIANJUN
• LI TIANGE
• HUANG XIANQING
• ZHANG YUHANG
• WANG TIANLIN
• QIAO MINGWU
• ZHAO QIUYAN

Assignees

• 河南农业大学

Dates

Publication Date

20260508

Application Date

20230217

Claims (5)

1. 1. S1, extracting pea protein isolate, namely dissolving pea raw materials in deionized water after crushing and sieving, wherein the feed liquid ratio of pea powder to water is 1:15-35 w/v, using an ultrasonic technology to assist dissolution, wherein the ultrasonic power is 100-500 w, the ultrasonic time is 10-30 min, the pH is 8-10, extracting protein in bean powder by an alkali-dissolution acid precipitation method, and freeze-drying to obtain pea protein isolate; S2, steam explosion treatment, namely adding the pea protein isolate powder obtained in the step S1 into a steam explosion cylinder of a steam explosion test bed to perform steam explosion treatment, wherein the steam explosion time is 20-100S, the steam explosion pressure is 0.4-1.2 MPa, and freeze-drying to obtain steam exploded pea protein isolate powder; S3, preparing pea polypeptide, namely dissolving the steam exploded pea protein isolate powder obtained in the step S2 in deionized water to prepare substrate concentration of 10%, regulating pH, respectively adding alkaline protease and neutral protease for enzymolysis reaction, extracting under the assistance of ultrasonic waves, inactivating enzyme at high temperature after the reaction is finished, centrifuging for 15min at 6000r/min, removing lower-layer sediment, collecting supernatant, and freeze-drying to obtain pea active polypeptide powder.
2. 2. The method of claim 1, wherein in step S1, the ratio of pea powder to water is 1:29w/v, the ultrasonic power is 260w, the ultrasonic time is 27min, and the pH value is 9.45.
3. 3. The method of claim 1, wherein in the step S2, the steam explosion time is 40S and the steam explosion pressure is 1.0MPa.
4. 4. The method of claim 1, wherein in the step S1, the pea material is protein-rich middle pea No. 9, and the peas are ground and sieved by a sieve of 40-100 meshes.
5. 5. The method according to claim 1, wherein in the step S1, the alkali-dissolution and acid-precipitation method comprises the specific steps of performing ultrasonic treatment, adjusting the pH to 8-10 with 1.0mol/L sodium hydroxide, continuously stirring the sample solution during the period, centrifuging to obtain a supernatant, adjusting the pH to 2.5-5.5 with hydrochloric acid, repeating the above steps for 2-3 times, and washing the precipitate with deionized water to neutrality.

Description

Multifunctional pea polypeptide and preparation method thereof Technical Field The invention belongs to the technical field of functional polypeptides, and particularly relates to a multifunctional pea polypeptide and a preparation method thereof. Background Pea is an important vegetable protein source, and has high nutrition benefit and low price, can realize mass preparation, and has wide market space. In addition, with the continuous improvement of dietary concepts of people, the continuous and deep research on protein substitution and the importance of people on the environment, the market demand of pea protein isolate is further increased. The bioactive polypeptide obtained by enzymolysis of the pea protein isolate not only has the advantages of easy absorption, safety and no side effect, but also has various functional activities such as anti-inflammatory, antioxidant, immunity regulating, blood sugar reducing and the like. At present, an enzymolysis method is commonly used for preparing the polypeptide, and more researches use a physical modification technology to assist enzymolysis so as to improve the yield and the functional activity of the protein peptide. For example, patent CN112626155B discloses a method for preparing pea peptide, which comprises pre-treating pea protein by high-pressure steam sterilization to expand the structure of pea protein for assisting composite enzymolysis, wherein the protein content of the prepared pea peptide powder is more than or equal to 90%, the peptide yield is 73%, but the high-pressure steam is only used for improving the subsequent enzymolysis reaction, and the functional characteristics of pea polypeptide are not studied. In another example, the application publication number is CN113197316A, and the preparation method thereof is that the bean-derived polypeptide with dual functions of depressurization activity and antioxidation activity is obtained by an infrared heat treatment assisted enzymolysis method, and the bean-derived polypeptide has good emulsifying property and emulsifying stability, but the antioxidation performance is still required to be further improved. Therefore, a new physical auxiliary enzymolysis method is needed to prepare pea polypeptide, so as to further improve the functional characteristics of pea protein polypeptide, such as antioxidation, blood pressure reduction and blood sugar reduction. Disclosure of Invention The invention aims to overcome the defects in the prior art and provide a preparation method of an antioxidant pea polypeptide, which utilizes a preparation method of steam explosion auxiliary enzymolysis, so that higher peptide yield is obtained, and the antioxidant pea polypeptide has the functions of resisting oxidation, reducing blood pressure and reducing blood sugar. In order to achieve the aim, the invention adopts the following technical scheme that the preparation method of the antioxidant pea polypeptide comprises the following steps: S1, pea protein isolate is extracted, namely pea raw materials are crushed, sieved and then dissolved in deionized water, the feed liquid ratio of pea powder to water is 1:15-35 w/v, ultrasonic technology is used for assisting in dissolution, the ultrasonic power is 100-500 w, the ultrasonic time is 10-30 min, the pH is 8-10, then protein in the bean powder is extracted by an alkali-dissolution acid precipitation method, and the pea protein isolate is obtained by freeze-drying; S2, steam explosion treatment, namely adding the pea protein isolate powder obtained in the step S1 into a steam explosion cylinder of a steam explosion test bed to perform steam explosion treatment, wherein the steam explosion time is 20-100S, the steam explosion pressure is 0.4-1.2 MPa, and freeze-drying to obtain steam exploded pea protein isolate powder; S3, preparing pea polypeptide, namely dissolving the steam exploded pea protein powder obtained in the step S2 in deionized water to prepare substrate concentration of 10%, regulating pH, respectively adding plant protease to perform enzymolysis reaction, inactivating enzyme at high temperature after the reaction is finished, performing ultrafiltration separation to obtain ultrafiltrate with molecular weight of less than 3kDa, and freeze-drying to obtain pea active polypeptide powder. In the step S1, preferably, the feed liquid ratio of the pea powder to the water is 1:29w/v, the ultrasonic power is 260w, the ultrasonic time is 27min, and the pH value is 9.45. In the step S2, preferably, the steam explosion time is 40S, and the steam explosion pressure is 1.0MPa. In the step S1, pea raw materials are protein-rich middle pea No. 9, and the peas are ground and sieved by a sieve with 40-100 meshes. In the step S1, the specific steps of the alkali-dissolution and acid-precipitation method are heating ultrasonic treatment, adjusting the pH to 8-10 by using 1.0mol/L sodium hydroxide, continuously stirring a sample solution during the ultrasonic treatment, cen