Production process of low-viscosity whitening carrageenan
Technical Field
The invention relates to the technical field of carrageenan extraction process of eucheuma, in particular to a production process of low-viscosity whitening carrageenan.
Background
Carrageenan, also known as carrageenan and carrageenin, is a water-soluble polysaccharide extracted from red algae such as carrageenin, and is a linear polysaccharide sulfate prepared by combining 1, 3-beta-D-galactopyranose and 1, 4-beta-D-galactopyranose. Carrageenan has the characteristics of gelling, thickening, emulsifying, film forming, stable dispersion and the like, and is widely applied to food industries of candies, meat, dairy products, brewing and the like. Carrageenan can also be used as a carrier for the study of microorganisms and immobilized cells. In addition, carrageenan is also used in pharmaceutical industries such as sustained release capsules/tablets, ointment bases, cod liver oil emulsifiers and the like.
The traditional extraction process of the carrageenan is obtained by treating and extracting eucheuma by NaOH-KCl, however, the carrageenan obtained by the method has high viscosity and is not easy to dissolve, and the application of the carrageenan is greatly limited. Alkali treatment is carried out on eucheuma by the Liuxuepin through KOH, so that carrageenan with lower viscosity and better quality is obtained. Li Guicun adopts H2O2Degrading the k-carrageenan to obtain the carrageenan with lower molecular weight, and improving the dissolubility of the carrageenan. And with H2O2The extraction process of Eucheuma Gelatinosum to obtain low viscosity carrageenan is not reported. In view of the above, the present inventors have studied and designed a process for producing a low viscosity whitening carrageenan, and have resulted therefrom.
Disclosure of Invention
The invention aims to provide a production process of low-viscosity whitening carrageenan by adopting a cleaning chemical reagent H2O2Processing Eucheuma Gelatinosum in extraction process to obtain carrageenan with low viscosity, low strength and improved whiteness, and has reduced production cost compared with chemical modification of carrageenan finished product, and H2O2Is a clean and pollution-free chemical reagent, can be repeatedly used and is suitable for industrial production.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a production process of low-viscosity whitening carrageenan comprises the following steps:
step one, cleaning raw materials: taking a proper amount of dry eucheuma, adding clear water with the weight being 20-100 times of that of the eucheuma, and rinsing to remove impurities;
step two, alkali treatment: adding alkali liquor into the cleaned eucheuma, soaking for 3-6 h at the constant temperature of 55-70 ℃ at the ratio of the materials to the liquor of 1: 20-1: 100g/ml, filtering out the alkali liquor, soaking with clear water, and rinsing to be neutral;
step three, low viscosity treatment: adding water according to a certain feed-liquid ratio, then adding an ethylene diamine tetraacetic acid disodium metal chelating agent with the final concentration of 0.012wt%, adjusting the pH value to 3-5 by using hydrochloric acid, and adding H with the final concentration of 0.25-1.5 wt%2O2Treating at normal temperature for 0.5-2 h, intermittently stirring, filtering, and rinsing filter residues to be neutral;
step four, bleaching treatment: adding water into the filter residue obtained in the third step according to the material-liquid ratio of 1:30g/ml, then adding a proper amount of bleaching water, treating for 2-4 h, filtering, and rinsing to be neutral;
step five, finished product: draining the bleached Eucheuma Gelatinosum, drying in the sun, pulverizing, sieving, and collecting powder.
In a preferable embodiment, in the first step, the material-to-water ratio for cleaning the eucheuma is 1: 30-1: 50 g/ml;
as a preferred mode of the embodiment, in the second step, the alkali liquor is a compound solution of 9-12 wt% of sodium hydroxide and 10-13 wt% of potassium chloride, preferably a compound solution of 10 wt% of sodium hydroxide and 12wt% of potassium chloride, and is treated at a constant temperature of 63 ℃ for 4 hours;
as a preferable mode of the embodiment, in the third step, the ratio of the materials to the liquid is 1:30g/ml, and the final concentration of the disodium ethylene diamine tetraacetate is 0.012 wt%;
in a preferable embodiment of the present invention, in the third step, the pH of the low viscosity treatment is 3.8 to 4.2;
as a preferable mode of the embodiment, H is used in the third step2O2The final concentration of the solution in a low-viscosity treatment system is 0.25-1.5 wt%, and the solution is treated for 1-2 hours at normal temperature;
in the fourth step, the amount of bleaching water is one twentieth of the weight of eucheuma, and the treatment time is 2-3 h;
in the fifth step, after draining off water, the Eucheuma Gelatinosum is dried in the sun, further dried in an oven at 55 ℃, crushed and sieved by a 80-mesh sieve for later use.
After the scheme is adopted, the invention passes through H under the acidic condition2O2The eucheuma is treated to degrade carrageenan molecules, so that the viscosity of the carrageenan is reduced.
Detailed Description
Example 1
Cleaning raw materials: taking 30g of dried eucheuma, adding 1000 ml of clear water for rinsing, and removing impurities;
alkali treatment: adding 10 wt% and 12wt% sodium hydroxide and potassium chloride compound alkali liquor with a liquor-feed ratio of 1:30g/ml, soaking at 63 deg.C for 4 hr, filtering to remove alkali liquor, soaking in clear water, and rinsing for several times;
bleaching treatment: adding water into the alkali-treated eucheuma in a material-liquid ratio of 1:30g/ml, adjusting the pH value to about 7 by using hydrochloric acid, adding 1.5 ml of bleaching water, treating for 3 hours, filtering, and rinsing to be neutral;
and (3) finished product: draining off water of Eucheuma Gelatinosum, drying in the sun in a tray, oven drying at 55 deg.C, pulverizing, sieving with 80 mesh sieve, and collecting powder.
The bleaching water is sodium hypochlorite stock solution with the effective chlorine content of 8 percent.
The carrageenan crude powder obtained in the example is detected to have the viscosity of 130.0 mPa.s and the gel strength of 560 g/cm2And the whiteness is 29.9 percent.
Example 2
Cleaning raw materials: taking 30g of dried eucheuma, adding 1000 ml of clear water for rinsing, and removing impurities;
alkali treatment: adding 800ml of compound alkali liquor of 10 wt% and 12wt% of sodium hydroxide and potassium chloride respectively, soaking at the constant temperature of 63 ℃ for 4 h, filtering out the alkali liquor, soaking with clear water, and rinsing to be neutral;
and (3) low-viscosity treatment: adding water into alkali-treated Eucheuma Gelatinosum at a ratio of 1:30g/ml, adding disodium edetate metal chelating agent with final concentration of 0.012wt%, adjusting pH to 4.0 with hydrochloric acid, and adding H with final concentration of 0.5 wt%2O2Treating at normal temperature for 1 h while intermittently stirring, filtering,rinsing the filter residue to be neutral;
bleaching treatment: adding water into the filter residue after low-viscosity treatment according to the material-liquid ratio of 1:30g/ml, then adding 1.5 ml of bleaching water, treating for 3 h, filtering, and rinsing to be neutral;
and (3) finished product: draining off water of Eucheuma Gelatinosum, drying in the sun in a tray, oven drying at 55 deg.C, pulverizing, sieving with 80 mesh sieve, and collecting powder.
The bleaching water is sodium hypochlorite stock solution with the effective chlorine content of 8 percent.
The carrageenan crude powder obtained in the example is detected to have the viscosity of 112.2 mPa.s and the gel strength of 433 g/cm2And the whiteness is 35.2 percent.
Example 3
Cleaning raw materials: taking 30g of dried eucheuma, adding 1000 ml of clear water for rinsing, and removing impurities;
alkali treatment: adding 800ml of compound alkali liquor of 10 wt% and 12wt% of sodium hydroxide and potassium chloride respectively, soaking at the constant temperature of 63 ℃ for 4 h, filtering out the alkali liquor, soaking with clear water, and rinsing to be neutral;
and (3) low-viscosity treatment: adding water into alkali-treated Eucheuma Gelatinosum at a ratio of 1:30g/ml, adding disodium edetate metal chelating agent with final concentration of 0.012wt%, adjusting pH to 4.0 with hydrochloric acid, and adding H with final concentration of 1.0 wt%2O2Treating at normal temperature for 1 h, intermittently stirring, filtering, and rinsing filter residue to neutrality;
bleaching treatment: adding water into the filter residue after low-viscosity treatment according to the material-liquid ratio of 1:30g/ml, then adding 1.5 ml of bleaching water, treating for 3 h, filtering, and rinsing to be neutral;
and (3) finished product: draining off water of Eucheuma Gelatinosum, drying in the sun in a tray, oven drying at 55 deg.C, pulverizing, sieving with 80 mesh sieve, and collecting powder.
The bleaching water is sodium hypochlorite stock solution with the effective chlorine content of 8 percent.
The carrageenan crude powder obtained in the embodiment is detected to have the viscosity of 101.5 mPa.s and the gel strength of 430 g/cm2And the whiteness is 40.1 percent.
Example 4
Cleaning raw materials: taking 30g of dried eucheuma, adding 1000 ml of clear water for rinsing, and removing impurities;
alkali treatment: adding 800ml of compound alkali liquor of 10 wt% and 12wt% of sodium hydroxide and potassium chloride respectively, soaking at the constant temperature of 63 ℃ for 4 h, filtering out the alkali liquor, soaking with clear water, and rinsing to be neutral;
and (3) low-viscosity treatment: adding water into alkali-treated Eucheuma Gelatinosum at a ratio of 1:30g/ml, adding disodium edetate metal chelating agent with final concentration of 0.012wt%, adjusting pH to 4.0 with hydrochloric acid, and adding H with final concentration of 1.5wt%2O2Treating at normal temperature for 1 h, intermittently stirring, filtering, and rinsing filter residue to neutrality;
bleaching treatment: adding water into the filter residue after low-viscosity treatment according to the material-liquid ratio of 1:30g/ml, then adding 1.5 ml of bleaching water, treating for 3 h, filtering, and rinsing to be neutral;
and (3) finished product: draining off water of Eucheuma Gelatinosum, drying in the sun in a tray, oven drying at 55 deg.C, pulverizing, sieving with 80 mesh sieve, and collecting powder.
The bleaching water is sodium hypochlorite stock solution with the effective chlorine content of 8 percent.
The carrageenan crude powder obtained in the embodiment is detected to have the viscosity of 85.0 mPa.s and the gel strength of 459 g/cm2And the whiteness is 37.6 percent.
Example 5
Cleaning raw materials: taking 60 g of dried eucheuma, adding 2000 ml of clear water for rinsing, and removing impurities;
alkali treatment: adding 1600ml of compound alkali liquor of sodium hydroxide and potassium chloride with the concentration of 10 wt% and 12wt% respectively, soaking at the constant temperature of 63 ℃ for 4 h, filtering out the alkali liquor, soaking with clear water, and rinsing to be neutral;
and (3) low-viscosity treatment: adding water into alkali-treated Eucheuma Gelatinosum at a ratio of 1:30g/ml, adding disodium edetate metal chelating agent with final concentration of 0.012wt%, adjusting pH to 4.0 with hydrochloric acid, and adding H with final concentration of 1.5wt%2O2Treating at normal temperature for 1 hr while stirring, filtering, and filteringRinsing the residues to be neutral;
bleaching treatment: adding water into the filter residue after low-viscosity treatment according to the material-liquid ratio of 1:30g/ml, then adding 3.0 ml of bleaching water, treating for 3 h, filtering, and rinsing to be neutral;
and (3) finished product: draining off water of Eucheuma Gelatinosum, drying in the sun in a tray, oven drying at 55 deg.C, pulverizing, sieving with 80 mesh sieve, and collecting powder.
The bleaching water is sodium hypochlorite stock solution with the effective chlorine content of 8 percent.
The carrageenan crude powder obtained in the example is detected to have the viscosity of 86.2 mPa.s and the gel strength of 460 g/cm2And the whiteness is 38.9 percent.
The invention adopts H2O2In the extraction process of the carrageenan, the eucheuma is treated, so that the chemical modification of the carrageenan is realized, a product with new performance is obtained, and the application field of the carrageenan is developed. By the use of H2O2The method is a clean and pollution-free chemical reagent, can be repeatedly used, and is suitable for industrial production of enterprises.
The main property parameters are as follows in table 1:
table 1 comparison of the main properties of the carrageenan powder obtained in examples 1 to 5
As can be seen from the data in Table 1, the process of the invention has a certain viscosity reduction effect on carrageenan, and simultaneously has different degrees of influence on the gel strength and whiteness of the carrageenan, wherein the gel strength is reduced, and the whiteness is slightly improved. This is because H2O2Has strong oxidation effect, and leads the molecular weight of the carrageenan to be reduced, so the viscosity and the gel strength of the carrageenan are reduced. And H2O2So as to pass through H2O2The whiteness of the treated carrageenan is improved to a certain extent.
The above examples are merely illustrative of the present invention and should not be construed as limiting the scope of the invention. All modifications which can be derived or suggested by a person skilled in the art from the present disclosure are to be considered within the scope of the invention.