Method for improving stability of natural beet red pigment in film coating

Abstract

The invention discloses a method for improving the stability of natural beet red pigment in a film coating, which comprises the following steps: step 1, starting a pulping barrel for stirring, slowly putting a beet red-containing film coating powder matrix into water in the pulping barrel, the weight ratio of coating powder to water is 1: (4-5), and the coating powder contains titanium dioxide; 2, citric acid is added, the weight ratio of the coating powder to the citric acid is (270-280): 1, stirring is conducted for 45 min, and coating slurry is discharged; and 3, sieving the coating slurry, and coating the tablets. The adsorption performance of titanium dioxide in the film coating slurry to beet red is improved through citric acid, so that the beet red can be better protected, no non-edible chemical additive is used, a very good inhibition effect on color fading of beet red caused by heat, oxidation and illumination can be achieved, the stability of the beet red can be effectively improved, and the service life of the beet red is prolonged. And the operation is simple and convenient.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a method for improving the stability of natural betalain in film coating. Background Art

[0002] Natural betalain is chemically unstable and is easily affected by environmental factors such as heat, pH, light, oxygen, and metal ions, causing hydrolysis or degradation, which affects its color and thus affects the shelf life of the product, greatly limiting the wide application of betalain in the food industry and related fields. At present, betalain is unstable when used as a red colorant in film coating. The tablets are pink after film coating, but they are easily faded by light, heat, etc. Chinese Patent Publication No.: CN108084731A, entitled "A Method for Improving the Stability of Betalain", discloses a method for improving the stability of betalain using soy protein fiber as a protective agent, but the method requires the soy protein solution to be heated in a water bath at a temperature of 85-95°C for a processing time of 8-12h, cooled in an ice bath, and obtained by freeze drying. The operation steps are relatively cumbersome and the operation time is long. Chinese Patent Publication No.: CN117859860A, entitled "A Heat-resistant Starch-based Beet Red Pigment and Its Preparation Method", discloses a heat-resistant starch-based bet red pigment and its preparation method, comprising the following preparation steps: (1) taking ascorbic acid and bet red pigment into an acetic acid sodium acetate buffer solution to dissolve, adding starch to stir and adsorb, centrifuging the obtained suspension to obtain a starch wet-based precipitate loaded with bet red pigment; (2) mixing the starch wet-based precipitate obtained in step (1) with a sodium alginate solution, and then drying, grinding, and sieving to obtain a heat-resistant starch-based bet red pigment microcapsule powder. The method is to adsorb pigments through the principle of starch granules swelling by water, and at the same time adsorb ascorbic acid and add sodium alginate to wrap the starch granules to obtain starch-based betalain pigment microcapsules. The thermal stability of betalain is improved mainly by adsorbing and wrapping betalain. The entire operation steps of the method are relatively complicated, and the adsorption, drying and other operation steps are time-consuming. The method only focuses on improving the thermal stability of betalain pigment and does not involve other stabilities. After it is configured into a coating slurry, the stability after film coating is unpredictable. Summary of the invention

[0003] In order to solve one or some technical problems existing in the prior art, the purpose of the present application is to provide a method for improving the stability of natural betalain in film coating, which can effectively improve the stability of betalain and is simple and convenient to operate.

[0004] In order to solve the above-mentioned existing technical problems, the purpose of the present application is achieved by adopting the following technical solution: a method for improving the stability of natural betalain red pigment in film coating, comprising the following steps:

[0005] Step 1: Start the pulping barrel for stirring, and slowly add the film coating powder matrix containing beetroot red into the water in the pulping barrel. The weight ratio of the coating powder to water is 1:4-5. The coating powder contains titanium dioxide.

[0006] Step 2: Add citric acid, the weight ratio of coating powder to citric acid is 270-280:1, stir for 45 minutes to release the coating slurry;

[0007] Step 3: Screen the coating slurry and coat the tablets.

[0008] Preferably, the coating powder consists of hydroxypropyl methylcellulose, polyvinyl alcohol, polyethylene glycol, talc, titanium dioxide and beetroot red.

[0009] Preferably, in step 1, the weight ratio of coating powder to water is 1:4.5.

[0010] Preferably, in step 1, the water temperature is maintained at 20-25° C., and the stirring speed of the pulping barrel is 400-800 rpm.

[0011] Preferably, in step 2, the weight ratio of coating powder to citric acid is 277.5:1.

[0012] Preferably, in step three, the coating slurry is passed through an 80-mesh sieve.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] A method for improving the stability of natural betalain pigment in film coating provided by the above technical scheme is used. The adsorption performance of titanium dioxide in the film coating slurry to betalain is improved by citric acid, so that the betalain can be better protected. No non-edible chemical additives are used. The fading of betalain pigment caused by heat, oxidation and light can be well inhibited, the stability of betalain can be effectively improved, and the operation is simple and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the initial state of 5 groups of coated tablets with different ratios;

[0016] Figure 2 The diagram is a schematic diagram of the discoloration of 5 groups of coated tablets with different ratios after 10 days;

[0017] Figure 3 The diagram is a schematic diagram of the discoloration of 5 groups of coated tablets with different ratios after 30 days;

[0018] Figure 4 The diagram is a schematic diagram of the discoloration of 5 groups of coated tablets with different ratios after 45 days; DETAILED DESCRIPTION

[0019] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0020] A method for improving the stability of natural betalain pigment in film coating comprises the following steps:

[0021] Step 1: Start the pulping barrel for stirring, and slowly add the film coating powder matrix containing beetroot red into the water in the pulping barrel. The weight ratio of the coating powder to water is 1:4-5. The coating powder contains titanium dioxide.

[0022] Step 2: Add citric acid, the weight ratio of coating powder to citric acid is 270-280:1, stir for 45 minutes to release the coating slurry;

[0023] Step 3: Screen the coating slurry and coat the tablets.

[0024] The coating powder consists of hydroxypropyl methylcellulose, polyvinyl alcohol, polyethylene glycol, talcum powder, titanium dioxide and beetroot red.

[0025] In the step 1, the weight ratio of the coating powder to water is 1:4.5.

[0026] In the step 1, the water temperature is maintained at 20-25° C., and the stirring speed of the pulping barrel is 400-800 rpm.

[0027] In the step 2, the weight ratio of the coating powder to the citric acid is 277.5:1.

[0028] In the step 3, the coating slurry is passed through an 80-mesh sieve.

[0029] The adsorption performance of titanium dioxide to beetroot red in the film coating slurry is improved by citric acid, so that it can better protect beetroot red. No non-edible chemical additives are used. It can effectively inhibit the fading of beetroot red pigment caused by heat, oxidation and light, and can effectively improve the stability of beetroot red. The operation is simple and convenient.

[0030] In order to examine the effect of citric acid on the adsorption capacity of titanium dioxide, five groups of coated tablets with different proportions were selected for comparison. After the tablets were coated, they were placed under the same accelerated conditions (light, humidity 75% RH, temperature 40°C) to observe their fading effects.

[0031]

[0032] like Figure 1 The initial state color is consistent; Figure 2 As shown in the figure, after 10 days, only the 4th group faded, while the other groups had no color change and no black spots appeared. The groups with citric acid added had good stability. Figure 3 As shown, after 30 days, the color remains almost unchanged; Figure 4 As shown, after 45 days, only the 5th group had no obvious fading, while the other groups all had varying degrees of fading.

[0033] The results show that when the weight ratio of coating powder to citric acid is 277.5:1, the adsorption capacity of titanium dioxide can be maximized, betalain can be better adsorbed, thereby improving the discoloration problem of tablets and maximizing the stability of natural betalain pigment in film coating.

[0034] The above-mentioned implementation modes are only preferred implementation modes of the present application and cannot be used to limit the scope of protection of the present application. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present application shall fall within the scope of protection required by the present application.

Claims

1. A method for improving the stability of natural betalain pigment in film coating, characterized in that: The following steps are involved: Step 1: Start the pulping barrel for stirring, and slowly add the film coating powder matrix containing beetroot red into the water in the pulping barrel. The weight ratio of the coating powder to water is 1:4-5. The coating powder contains titanium dioxide. Step 2: Add citric acid, the weight ratio of coating powder to citric acid is 270-280:1, stir for 45 minutes to release the coating slurry; Step 3: Screen the coating slurry and coat the tablets.

2. A method for improving the stability of natural betalain pigment in film coating according to claim 1, characterized in that: The coating powder consists of hydroxypropyl methylcellulose, polyvinyl alcohol, polyethylene glycol, talcum powder, titanium dioxide and beetroot red.

3. A method for improving the stability of natural betalain pigment in film coating according to claim 1, characterized in that: In the step 1, the weight ratio of the coating powder to water is 1:4.

5.

4. A method for improving the stability of natural betalain pigment in film coating according to claim 1, characterized in that: In the step 1, the water temperature is maintained at 20-25° C., and the stirring speed of the pulping barrel is 400-800 rpm.

5. The method for improving the stability of natural betalain pigment in film coating according to claim 1, characterized in that: In the step 2, the weight ratio of the coating powder to the citric acid is 277.5:

1.

6. The method for improving the stability of natural betalain pigment in film coating according to claim 1, characterized in that: In the step 3, the coating slurry is passed through an 80-mesh sieve.

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