High-stability food ink and preparation method thereof

Abstract

The invention relates to the field of food, in particular to high-stability food ink and a preparation method thereof. The food ink is prepared from the following raw materials: a coating agent, a solvent, a surfactant, an emulsifier and purified water, wherein the coating agent comprises chitosan, the surfactant comprises monoglyceride fatty acid ester or diglyceride fatty acid ester, and the emulsifier comprises Tween 20 and Span 20; the food ink prepared by the invention is smooth in printing, excellent in adhesion performance on the surface of food after printing, relatively high in storage stability and very good in actual use effect.

Description

Technical Field

[0001] The invention relates to the field of food, in particular to a high-stability food ink and a preparation method thereof. Background Art

[0002] Printing appropriate patterns on the surface of food can not only play the role of identification and improve the "appearance" of food, but also increase consumers' desire to buy, especially some young consumers who prefer food with exquisite appearance. Food surface printing mainly uses food ink. For food ink, the most basic and core requirement is that the raw materials must be healthy and harmless. In addition, if the food ink itself has a certain flavor, such as chocolate flavor, fruit flavor, etc., it can further increase the taste of the food and attract more customers to buy again.

[0003] At present, food surface printing technology can only be applied to some pastries with good surface absorption, resulting in a relatively narrow application range of food ink. How to develop a food ink that can normally print patterns on smooth surfaces, foods that are difficult for oil to adhere to, or special functional foods is very important for expanding the application range of food surface printing technology and promoting food innovation. In addition, even if food ink can normally print patterns on food surfaces, the storage stability of the patterns is also an important factor that needs to be considered.

[0004] The prior art CN102101953B discloses an edible ink, the raw materials for its preparation mainly include: a solvent, an edible colorant and shellac; however, the inventors found in the actual research and development process that the food ink prepared with shellac as the raw material has relatively poor storage stability. Therefore, how to improve the storage stability of food ink has become the main problem that needs to be overcome at this stage. Summary of the invention

[0005] In order to solve the above technical problems, the first aspect of the present invention provides a highly stable food ink, the preparation raw materials of which include: a coating agent, a solvent, a surfactant, an emulsifier, and purified water.

[0006] As an implementable case, the food ink comprises, by weight: 0.1-2 parts of a coating agent, 10-50 parts of a solvent, 0.1-2 parts of a surfactant, 1-5 parts of an emulsifier, and 50-80 parts of purified water.

[0007] Furthermore, the food ink comprises, by weight, 0.5 parts of a coating agent, 30 parts of a solvent, 0.5 parts of a surfactant, 1.5 parts of an emulsifier, and 67.5 parts of purified water.

[0008] As an implementable case, the coating agent includes: one or more of hyaluronic acid, sodium hyaluronate, alginic acid, chitosan, palm wax, fruit wax, gelatin, pectin, and fiber.

[0009] Furthermore, the coating agent includes at least one of hyaluronic acid, sodium hyaluronate, alginic acid and chitosan.

[0010] Furthermore, the coating agent is chitosan.

[0011] Chitosan is a natural polysaccharide with biodegradability and cell affinity. Therefore, the present invention preferably uses chitosan as the coating agent of food ink. Compared with the chemical components in traditional inks, the use of chitosan effectively reduces the toxicity of food ink. In addition, the most important point is that since the amino groups in chitosan molecules carry positive charges, the reaction activity is strong and can adsorb negatively charged substances, food ink can be effectively adsorbed on the surface of food with a relatively smooth surface, thereby significantly improving the storage stability of food ink. In addition, chitosan can also be used as a carrier of pigments to effectively disperse and fix pigments and improve the printing effect of food ink. At the same time, chitosan has excellent film-forming properties. Under the joint action of emulsifiers and surfactants, it can form a semi-permeable membrane on the surface of food, regulate the internal environment of food, inhibit the metabolism and water dissipation of food, and achieve the purpose of preservation. Chitosan also has excellent antibacterial properties, which can effectively inhibit the growth and reproduction of various spoilage bacteria, slow down lipid oxidation, inhibit protein degradation, reduce microbial contamination, and effectively maintain the hygienic quality and safety of food.

[0012] As an implementable case, the surfactant includes at least one of monoglycerol fatty acid ester, diglycerol fatty acid ester, acetylated monoglycerol fatty acid ester, acetylated diglycerol fatty acid ester, polyglycerol fatty acid ester, and sucrose fatty acid ester.

[0013] Furthermore, the surfactant includes: monoglycerol fatty acid ester and / or diglycerol fatty acid ester.

[0014] In the raw material system of food ink, both monoglycerol fatty acid esters and diglycerol fatty acid esters can form a protective film covering the surface of the pigment to prevent the pigment from settling or stratifying due to gravity; this protective effect helps to improve the uniformity and stability of food ink; in addition, both monoglycerol fatty acid esters and diglycerol fatty acid esters have certain anti-aging properties, which can prevent food ink from degradation or deterioration due to environmental factors such as light and temperature, so compared with other surfactants, they have a better effect of improving storage stability.

[0015] As an implementable case, the emulsifier includes: one or more of a Span emulsifier, a Tween emulsifier, and a cyclodextrin.

[0016] As an implementable case, the Span emulsifier includes: one or more of Span 20, Span 60, and Span 80.

[0017] As an implementable case, the Tween emulsifier includes: one or more of Tween 20, Tween 60, and Tween 80.

[0018] As an implementable case, the cyclodextrin includes: one or more of α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin.

[0019] Furthermore, the emulsifier includes: Tween 20 and Span 20, and the mass ratio of the two is (1-5): (1-5).

[0020] Tween 20 can reduce the surface tension of the system, making food ink easier to flow and spread. Span 20 mainly focuses on oil solubility, which can improve the fluidity of the raw material system to a certain extent and enhance the adhesion of food ink on the surface of oily food. Monoglycerol fatty acid esters and diglycerol fatty acid esters can also improve the fluidity of the system, making food ink easier to print. The synergistic effect of the three can further enhance the adhesion of food ink on the food surface, thereby improving the storage stability of food ink.

[0021] As an implementable case, the solvent includes: one or more of anhydrous ethanol, 1,2-propylene glycol, glycerol, n-butanol, n-hexanol, sorbitol (liquid), and isopropanol.

[0022] Furthermore, the solvent includes: 1,2-propylene glycol, glycerol, and anhydrous ethanol.

[0023] Furthermore, the mass ratio of the 1,2-propylene glycol, glycerol and anhydrous ethanol is (5-20): (5-20): (3-10).

[0024] The food ink provided by the present invention can also be added with different types of pigments according to actual needs, including but not limited to: one or more of brilliant blue, lemon yellow, sunset yellow, safflower yellow, citrus yellow, capsicum red, cochineal red, erythrosine, allura red, beet red, curcumin, radish red, phycocyanin, carotene

[0025] A second aspect of the present invention provides a method for preparing a highly stable food ink, comprising:

[0026] S1. Mix and stir the film-forming agent and purified water until the film-forming agent is completely dissolved;

[0027] S2, add the solvent, place in a disperser, and disperse at high speed for 20-40 minutes at 20-60°C and 500-800rpm;

[0028] S3, add surfactant and emulsifier, and disperse at high speed for 20-40 minutes at 20-30°C and 500-800rpm;

[0029] S4. Filter using micron filter paper to obtain.

[0030] Beneficial Effects

[0031] (i) The food ink provided by the present invention can print coatings on the surface of food, especially on foods with smooth surfaces, foods with oils and fats, and foods with special functional properties; the printed patterns are bright in color and have excellent adhesion properties.

[0032] (ii) The food ink provided by the present invention preferably uses chitosan as the coating agent, mainly because there are positively charged amino groups in the chitosan molecule, which have strong reaction activity and can adsorb negatively charged substances, thereby significantly improving the adhesion performance and storage stability of the food ink; at the same time, chitosan also has certain antibacterial properties, which can improve the antibacterial properties of the product.

[0033] (III) The inventors also found in the actual research and development process that different surfactants have a certain influence on the stability of food ink. Since monoglycerol fatty acid esters and diglycerol fatty acid esters have certain anti-aging properties, they can prevent food ink from being degraded or deteriorated due to environmental factors such as light and temperature. Therefore, they have better storage stability effect than other surfactants.

[0034] (IV) The preferred emulsifier in the present invention is a compound of Tween 20 and Span 20, which can work together with the surfactant to ensure that the food ink can be smoothly printed on the surface of oily food.

[0035] (V) The food ink provided by the present invention has a relatively simple preparation method, can be industrialized for production, and has a wide range of raw materials for preparation, and all meet the relevant safety requirements of GB 2760-2014. The food ink will not clog the nozzle of the printer during printing, is not easy to aggregate, has good printing spreadability, and has excellent practical use effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the printing effect of the food ink prepared in Example 1.

[0037] Figure 2 This is a schematic diagram of the printing effect of the food ink prepared in Comparative Example 1. DETAILED DESCRIPTION

[0038] Example 1

[0039] The first aspect of this example provides a highly stable food ink, the raw materials of which, by weight, include: 0.5 parts of a coating agent, 30 parts of a solvent, 0.5 parts of a surfactant, 1.5 parts of an emulsifier, and 67.5 parts of purified water.

[0040] The coating agent is chitosan.

[0041] The solvent is a compound of 1,2-propylene glycol, glycerol and anhydrous ethanol; the mass ratio of the three is 2:3:1.

[0042] The surfactant is monoglyceride fatty acid ester.

[0043] The emulsifier is a compound of Tween 20 and Span 20, and the mass ratio of the two is 2:1.

[0044] All of the above-mentioned raw materials are common commercially available products.

[0045] The second aspect of this example provides a method for preparing a highly stable food ink, comprising:

[0046] S1. Mix and stir the film-forming agent and purified water until the film-forming agent is completely dissolved;

[0047] S2, add the solvent, place in a disperser, and disperse at high speed for 30 minutes at 40°C and 600 rpm;

[0048] S3, add surfactant and emulsifier, and disperse at high speed for 30 minutes at 25°C and 600 rpm;

[0049] S4. Filter using 0.22 μm filter paper to obtain.

[0050] Comparative Example 1

[0051] The first aspect of this example provides a highly stable food ink, the raw materials of which, by weight, include: 0.5 parts of a coating agent, 30 parts of a solvent, 0.5 parts of a surfactant, 1.5 parts of an emulsifier, and 67.5 parts of purified water.

[0052] The coating agent is corn protein (commonly available in the market).

[0053] The solvent is a compound of 1,2-propylene glycol, glycerol and anhydrous ethanol; the mass ratio of the three is 2:3:1.

[0054] The surfactant is monoglyceride fatty acid ester.

[0055] The emulsifier is a compound of Tween 20 and Span 20, and the mass ratio of the two is 2:1.

[0056] All of the above-mentioned raw materials are common commercially available products.

[0057] The second aspect of this example provides a method for preparing a highly stable food ink, comprising:

[0058] S1. Mix and stir the film-forming agent and purified water until the film-forming agent is completely dissolved;

[0059] S2, add the solvent, place in a disperser, and disperse at high speed for 30 minutes at 40°C and 600 rpm;

[0060] S3, add surfactant and emulsifier, and disperse at high speed for 30 minutes at 25°C and 600 rpm;

[0061] S4. Filter using 0.22 μm filter paper to obtain.

[0062] Comparative Example 2

[0063] The first aspect of this example provides a highly stable food ink, the raw materials of which, by weight, include: 0.5 parts of a coating agent, 30 parts of a solvent, 0.5 parts of a surfactant, 1.5 parts of an emulsifier, and 67.5 parts of purified water.

[0064] The coating agent is shellac.

[0065] The solvent is a mixture of 1,2-propylene glycol, glycerol and anhydrous ethanol, and the mass ratio of the three is 2:3:1.

[0066] The surfactant is monoglyceride fatty acid ester.

[0067] The emulsifier is a compound of Tween 20 and Span 20, and the mass ratio of the two is 2:1.

[0068] All of the above-mentioned raw materials are common commercially available products.

[0069] The second aspect of this example provides a method for preparing a highly stable food ink, comprising:

[0070] S1. Mix and stir the film-forming agent and purified water until the film-forming agent is completely dissolved;

[0071] S2, add the solvent, place in a disperser, and disperse at high speed for 30 minutes at 40°C and 600 rpm;

[0072] S3, add surfactant and emulsifier, and disperse at high speed for 30 minutes at 25°C and 600 rpm;

[0073] S4. Filter using 0.22 μm filter paper to obtain.

[0074] Comparative Example 3

[0075] The specific implementation of this example is the same as that of Example 1, except that the coating agent is glyceryl citrate.

[0076] Comparative Example 4

[0077] The specific implementation of this example is the same as that of Example 1, except that the coating agent is triacetin.

[0078] Comparative Example 5

[0079] The specific implementation of this example is the same as that of Example 1, except that the coating agent is triethyl citrate.

[0080] Comparative Example 6

[0081] The specific implementation of this example is the same as that of Example 1, except that the coating agent is polyglycerol fatty acid ester (commonly available on the market).

[0082] Performance Evaluation

[0083] Test object: food ink prepared in Example 1 and Comparative Examples 1-2.

[0084] Stability: After storage at high temperature of 50°C for 15 days, the viscosity, filterability, surface tension and pH value are tested to be within the index range; if they are all within the qualified index range, it is recorded as qualified, otherwise it is recorded as unqualified.

[0085] Among them, the qualified index range of viscosity is 5-8cP; the qualified index range of filterability is: 0.22μm filter membrane filtration for 3-5min (take 300 grams of food ink and filter it with a filter, the filter membrane is 0.22μm, the faster the filtration time, the better the filterability); the qualified index range of pH value is: 5-7; the qualified index range of surface tension is: 24-32N / m.

[0086] Moisture resistance: Put the food ink in a refrigerator at 5℃ for 24h, and then observe whether the surface spreads.

[0087] Printing effect: Observe whether the printed pattern is clear and whether there is any ink accumulation.

[0088] Nozzle adaptability: Print with food ink continuously for 8 hours and observe whether the needle breaks during the printing process.

[0089] Fluency: Observe whether the printed pattern is smooth and unbroken.

[0090] The test results are shown in Table 1.

[0091] Table 1

[0092] Moisture resistance Printing effect stability Nozzle adaptability Fluency Example 1 Non-proliferation good qualified No plugging Good effect Comparative Example 1 diffusion Poly Ink Failure Plug Disconnection Comparative Example 2 diffusion Poly Ink Failure Plug Disconnection

[0093] Printing effect test: The test objects are Example 1 and Comparative Example 1. The test results are detailed in Figure 1 and Figure 2 As can be seen from the figure, after the food ink prepared in Example 1 is printed with a pattern, there is no diffusion after being placed at 25°C for 7 days. After the food ink prepared in Comparative Example 1 is printed with a pattern, part of the pattern diffuses after being placed at 25°C for 1 day.

[0094] Test object: food inks prepared in Example 1 and Comparative Examples 3-6.

[0095] Test item: nozzle adaptability. See Table 2 for test results.

[0096] Table 2

[0097] Nozzle adaptability Example 1 Good printing fluency, clear proofing, and not prone to clogging Comparative Example 3 Better waterproofness, easier to plug Comparative Example 4 Better waterproofness, easier to plug Comparative Example 5 Better waterproofness, easier to plug Comparative Example 6 Printing coating is easy to spread and not easy to clog

[0098] In Comparative Examples 3-5, the hydrophobicity of the coating pattern is significantly improved after using glyceryl citrate, glyceryl triacetate, and triethyl citrate. However, since glyceryl citrate, glyceryl triacetate, and triethyl citrate are relatively more volatile, they are prone to clogging during the printing process.

[0099] In Comparative Example 6, the hydrophobicity of polyglycerol ester is average, but it is not easy to volatilize, so it is not easy to clog the head. However, after printing, the food ink has poor volatility, so it is not easy to form a coating. The food ink will spread on the surface of the food, causing the pattern to become "flowery".

Claims

1. A highly stable food ink, characterized in that: The preparation raw materials include: film coating agent, solvent, surfactant, emulsifier and purified water.

2. The highly stable food ink according to claim 1, characterized in that: The food ink comprises, by weight, 0.1-2 parts of a film coating agent, 10-50 parts of a solvent, 0.1-2 parts of a surfactant, 1-5 parts of an emulsifier, and 50-80 parts of purified water.

3. The highly stable food ink according to claim 1, characterized in that: The coating agent comprises: one or more of hyaluronic acid, sodium hyaluronate, alginic acid, chitosan, palm wax, fruit wax, gelatin, pectin and fiber.

4. The highly stable food ink according to claim 1, characterized in that: The surfactant comprises at least one of monoglycerol fatty acid ester, diglycerol fatty acid ester, acetylated monoglycerol fatty acid ester, acetylated diglycerol fatty acid ester, polyglycerol fatty acid ester and sucrose fatty acid ester.

5. The highly stable food ink according to any one of claims 1 to 4, characterized in that: The emulsifier includes: one or more of Span emulsifiers, Tween emulsifiers, and cyclodextrin.

6. The highly stable food ink according to claim 5, characterized in that: The Span emulsifier includes one or more of Span 20, Span 60 and Span 80; The Tween emulsifier includes one or more of Tween 20, Tween 60 and Tween 80; The cyclodextrin includes one or more of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin.

7. The highly stable food ink according to claim 6, characterized in that: The emulsifier includes: Tween 20 and Span 20, and the mass ratio of the two is (1-5): (1-5).

8. The highly stable food ink according to claim 1, characterized in that: The solvent includes: one or more of anhydrous ethanol, 1,2-propylene glycol, glycerol, n-butanol, n-hexanol, sorbitol (liquid), and isopropanol.

9. The highly stable food ink according to claim 8, characterized in that: The mass ratio of the 1,2-propylene glycol, glycerol and anhydrous ethanol is (5-20): (5-20): (3-10).

10. A method for preparing a highly stable food ink according to any one of claims 1 to 9, characterized in that: include: S1. Mix and stir the film-forming agent and purified water until the film-forming agent is completely dissolved; S2, add the solvent, place in a disperser, and disperse at high speed for 20-40 minutes at 20-60°C and 500-800rpm; S3, add surfactant and emulsifier, and disperse at high speed for 20-40 minutes at 20-30°C and 500-800rpm; S4. Filter using micron filter paper to obtain.

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