阅读说明：本技术 一种从脱胶海带粉中提取海带蛋白的方法 (Method for extracting kelp protein from degummed kelp powder ) 是由 李胜杰 沈宇晴 赵亚楠 李秀萍 王雯慧 王守印 于 2021-07-08 设计创作，主要内容包括：本发明提供一种从脱胶海带粉中提取海带蛋白的方法,包括以下步骤：称取脱胶海带粉于离心管,按照1：20料液比加入去离子水浸泡12～14小时；离心除去水提液；向沉淀中加入去离子水、NaOH及L-半胱氨酸,混合均匀；在20～70℃下,恒温震荡3～15h；离心得到浸提上清液,使用盐酸调节pH值至1～6；离心后除去上清液,喷雾干燥沉淀后得到海带蛋白。本发明通过在提取蛋白中加入L-半胱氨酸,提高了海带蛋白的提取效率,借助L-半胱氨酸促进蛋白溶出,建立了一种高效稳定的海带蛋白提取方法。(The invention provides a method for extracting kelp protein from degummed kelp powder, which comprises the following steps: weighing degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20, soaking for 12-14 hours in deionized water compared with the feed liquid; centrifuging to remove water extract; adding deionized water, NaOH and L-cysteine into the precipitate, and uniformly mixing; shaking for 3-15 h at a constant temperature of 20-70 ℃; centrifuging to obtain a supernatant liquid, and adjusting the pH value to 1-6 by using hydrochloric acid; centrifuging, removing supernatant, spray drying, and precipitating to obtain kelp protein. The invention improves the extraction efficiency of the kelp protein by adding the L-cysteine into the extracted protein, promotes the dissolution of the protein by means of the L-cysteine, and establishes a high-efficiency and stable kelp protein extraction method.)

1. A method for extracting kelp protein from degummed kelp powder is characterized by comprising the following steps:

s1, weighing 1 part of degummed kelp powder, adding deionized water according to the material-liquid ratio of 1:20, and soaking for 12-14 hours;

s2, centrifuging to obtain a precipitate;

s3, adding deionized water into the precipitate, adding 0.6-1 part of NaOH, adding 0.25-1.25 parts of L-cysteine, and uniformly mixing;

s4, shaking at a constant temperature of 20-70 ℃ for 3-15 h to obtain a leaching solution;

s5, centrifuging the leaching solution obtained in the step S4 to obtain a leaching supernatant, and adjusting the pH value of the leaching supernatant to 1-6;

s6, centrifuging to remove supernatant, precipitating to obtain total protein extract, and spray drying to obtain sea tangle protein.

2. The method for extracting kelp protein from degummed kelp powder according to claim 1, wherein the centrifugation conditions of step S2 comprise centrifugation at 12000g of centrifugal force at 4 ℃ for 20 min.

3. The method for extracting kelp protein from degummed kelp powder according to claim 1, wherein the centrifugation conditions in the step S5 comprise centrifugation at 12000g of centrifugal force at 20-25 ℃ for 20 min.

4. The method for extracting kelp protein from degummed kelp powder according to claim 1, wherein the centrifugation condition of step S6 comprises centrifugation at 12000g of centrifugal force at 20-25 ℃ for 20 min.

5. The method for extracting kelp protein from degummed kelp powder according to claim 1, wherein the pH of the extraction supernatant is adjusted to 1-6 using hydrochloric acid in the step S5.

Technical Field

The invention relates to a protein extraction technology, and particularly provides a method for extracting kelp protein from degummed kelp powder.

Background

With the increasing scarcity of land protein resources, the marine algae has been gradually valued as a source of novel protein resources, the nutritional value of the algae is fully utilized, the requirement of people on high-quality protein is met, and a feasible way is provided for improving the development capacity of marine resources and developing marine economy.

Domestic kelp processing enterprises mainly extract iodine, mannitol and algin, and the waste residue liquid of the extracted kelp is discarded to cause resource waste and environmental pollution.

Therefore, the method for extracting the kelp protein from the degummed kelp powder can replace traditional proteins such as soybean protein and the like by the kelp protein to relieve the current situation of shortage of soybean protein resources, and can solve the problems of waste of resources, low technical utilization rate and low extraction rate in the prior art.

Disclosure of Invention

The invention aims to provide a method for extracting kelp protein from degummed kelp powder aiming at the problems of land resource shortage and difficult protein extraction at present, and provides an effective way for green and efficient production of kelp protein.

In order to achieve the above object, the present invention provides a method for extracting kelp protein from degummed kelp powder, comprising the steps of:

s1, weighing 1 part of degummed kelp powder, adding deionized water according to the material-liquid ratio of 1:20, and soaking for 12-14 hours;

s2, centrifuging to obtain a precipitate;

s3, adding deionized water into the precipitate, adding 0.6-1 part of NaOH, adding 0.25-1.25 parts of L-cysteine, and uniformly mixing;

s4, shaking at a constant temperature of 20-70 ℃ for 3-15 h to obtain a leaching solution;

s5, centrifuging the leaching solution obtained in the step S4 to obtain a leaching supernatant, and adjusting the pH value of the leaching supernatant to 1-6;

s6, centrifuging to remove supernatant, precipitating to obtain total protein extract, and spray drying to obtain sea tangle protein.

Preferably, the centrifugation conditions of step S2 include centrifugation at 12000g of centrifugal force at 4 ℃ for 20 min.

Preferably, the centrifugation conditions of step S5 include centrifugation at 12000g of centrifugal force at 20-25 ℃ for 20 min.

Preferably, the centrifugation conditions of step S6 include centrifugation at 12000g at 20-25 ℃ for 20 min.

Preferably, hydrochloric acid is used to adjust the pH value of the leaching supernatant to 1-6 in the step S5.

The invention provides a method for extracting kelp protein from degummed kelp powder, which is characterized in that the additive amount of NaOH, the additive amount of L-cysteine, the leaching temperature, the leaching time and the pH value of acid precipitation are optimized by a PH-shifting method, so that the extraction efficiency of the kelp protein is improved, the dissolution of the protein is promoted by virtue of the L-cysteine, and a high-efficiency and stable kelp protein extraction method is established. In particular, the following advantages are obtained in comparison with the prior art:

(1) the method adopts a mode of adding solid NaOH, and carries out equal proportion conversion addition according to the initial mass of the raw materials, so that the operation of preparing NaOH solution in advance is reduced, the production process is easy to amplify, the steps of measuring and adjusting the pH value are reduced, the repeatability, the accuracy and the convenience in actual operation are obviously improved, and the operation error caused by inaccurate pH value adjustment and the protein yield and the quality difference between different batches caused by the operation error are reduced.

(2) The L-cysteine is added, so that disulfide bonds in cell walls of the degummed kelp powder can be reduced, the dissolution of protein is promoted, and the protein yield is improved.

(3) The invention optimizes the industrial production steps, improves the production efficiency, relieves the current resource waste phenomenon and has excellent industrialization prospect.

Detailed Description

In order to make the advantages and purposes of the present invention more apparent, the technical solutions of the present invention are described in detail below with reference to specific examples, but the scope of the present invention is not limited to the examples.

The instrument reagents used in the examples are shown in tables 1 and 2.

TABLE 1 reagents and purities

TABLE 2 instruments and models

Example 1

S1, weighing 0.2g of degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20 material-liquid ratio, adding deionized water and soaking for 12-14 hours;

s2, centrifuging at 12000g of centrifugal force for 20min at 4 ℃ to remove the water extract and obtain a precipitate;

s3, adding 20ml of deionized water into the precipitate, adding 0.14g of NaOH, adding 0.1g of L-cysteine, and uniformly mixing;

s4, shaking for 3h at a constant temperature of 60 ℃ to obtain a leaching solution;

s5, centrifuging the leaching solution for 20min at the environment of 20 ℃ and the centrifugal force of 12000g to obtain the leaching supernatant, and adjusting the pH value to 3 by using hydrochloric acid;

s6, mixing uniformly, centrifuging at 12000g at 20 ℃ for 20min, removing supernatant, precipitating to obtain total protein extract, and spray drying to obtain the kelp protein.

Example 2

S1, weighing 0.2g of degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20 material-liquid ratio, adding deionized water and soaking for 12-14 hours;

s2, 12000g, centrifuging for 20min at 4 ℃ to remove water extract, and obtaining precipitate;

s3, adding 20ml of deionized water into the precipitate, adding 0.12g of NaOH, adding 0.05g of L-cysteine, and uniformly mixing;

s4, shaking for 6h at a constant temperature of 20 ℃ to obtain a leaching solution;

s5, centrifuging the leaching solution for 20min at the centrifugal force of 12000g and at the temperature of 20 ℃ to obtain leaching supernatant, and adjusting the pH value to 5 by using hydrochloric acid;

s6, mixing uniformly, centrifuging at the centrifugal force of 12000g at 20 ℃ for 20min, removing supernatant, precipitating to obtain total protein extract, and spray drying the total protein extract to obtain the degummed kelp protein.

Example 3

S1, weighing 0.2g of degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20 material-liquid ratio, adding deionized water and soaking for 12-14 hours;

s2, centrifuging for 20min at the centrifugal force of 12000g and the temperature of 4 ℃, and removing water extract to obtain precipitate;

s3, adding 20ml of deionized water into the precipitate, adding 0.16g of NaOH, adding 0.15g of L-cysteine, and uniformly mixing;

s4, shaking at constant temperature of 30 ℃ for 12h to obtain a leaching solution;

s5, centrifuging the leaching solution at 12000g at 20 ℃ for 20min to obtain a leaching supernatant, and adjusting the pH value to 4 by using hydrochloric acid;

s6, mixing uniformly, centrifuging for 20min at 12000g and 20 ℃, removing supernatant, precipitating to obtain total protein extract, and spray drying the total protein extract to obtain the kelp protein.

Example 4

S1, weighing 0.2g of degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20 material-liquid ratio, adding deionized water and soaking for 12-14 hours;

s2, centrifuging for 20min at the centrifugal force of 12000g and the temperature of 4 ℃, and removing water extract to obtain precipitate;

s3, adding 20ml of deionized water into the precipitate, adding 0.18g of NaOH, adding 0.1g of L-cysteine, and uniformly mixing;

s4, shaking at constant temperature of 40 ℃ for 15h to obtain a leaching solution;

s5, centrifuging the leaching solution for 20min at 12000g and 20 ℃ to obtain leaching supernatant, and adjusting the pH value to 3 by using hydrochloric acid;

s6, mixing uniformly, centrifuging for 20min at 12000g and 20 ℃, removing supernatant, precipitating to obtain total protein extract, and spray drying the total protein extract to obtain the kelp protein.

Example 5

S1, weighing 0.2g of degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20 material-liquid ratio, adding deionized water and soaking for 12-14 hours;

s2, centrifuging at 12000g of centrifugal force and 4 ℃ for 20min, and removing water extract to obtain precipitate;

s3, adding 20ml of deionized water into the precipitate, adding 0.2g of NaOH, adding 0.2g of L-cysteine, and uniformly mixing;

s4, shaking at a constant temperature of 50 ℃ for 9h to obtain a leaching solution;

s5, centrifuging the leaching solution at 12000g at 25 ℃ for 20min to obtain a leaching supernatant, and adjusting the pH value to 6 by using hydrochloric acid;

s6, mixing uniformly, centrifuging at 12000g at 25 deg.C for 20min, removing supernatant, precipitating to obtain total protein extract, and spray drying to obtain Laminarin.

Comparative example 1

S1, weighing 0.2g of degummed kelp powder in a centrifuge tube according to the weight ratio of 1:20 material-liquid ratio, adding deionized water and soaking for 12-14 hours;

s2, centrifuging for 20min at 12000g and 4 ℃, and removing water extract to obtain precipitate;

s3, adding 20ml of deionized water into the precipitate, adding 0.2g of NaOH, and uniformly mixing;

s4, shaking for 3h at a constant temperature of 60 ℃ to obtain a leaching solution;

s5, centrifuging the leaching solution at 12000g at 20 ℃ for 20min to obtain a leaching supernatant, and adjusting the pH value to 3 by using hydrochloric acid;

s6, mixing uniformly, centrifuging for 20min at 12000g and 20 ℃, removing supernatant, precipitating to obtain total protein extract, and spray drying the total protein extract to obtain the kelp protein.

The protein concentration of the kelp protein extracted in the embodiments 1 to 5 and the comparative example 1 was measured by using a Lowry kit with 1g of the degummed kelp powder as a weight basis, and the results are shown in table 3, and the protein extraction rate of the most preferred embodiment (embodiment 1) reached 39.55%; in addition, the protein extraction rate of the examples 1-5 d with the L-cysteine is much higher than that of the comparative example 1 without the L-cysteine, which shows that the addition of the L-cysteine can promote the dissolution of the protein and effectively improve the protein extraction rate.

TABLE 3 extraction of Laminarin under different optimized conditions

	Protein extraction ratio (%)
		Example 1	39.55
Example 2	22.49
		Example 3	36.32
Example 4	35.86
		Example 5	35.39
Comparative example 1	11.08

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.