Green preparation technology for improving quality of fermented leaf mustard

Abstract

The invention belongs to the field of fermented vegetables, and discloses a green preparation technology for improving the quality of fermented mustard. The fermented leaf mustard consists of the following components in parts by mass: 500-600 parts of water, 300-400 parts of leaf mustard, 40-60 parts of salt, 60-80 parts of white sugar and 0.05-0.1 part of compound essential oil. Wherein the compound essential oil comprises the following components: lemon essential oil, citronella essential oil and myristica fragrans essential oil, and the optimal mass ratio of the lemon essential oil to the citronella essential oil to the myristica fragrans essential oil is 1: 1: 1. Through compounding and cooperation of the essential oil, under the condition that normal fermentation of the pickles is not affected, the nitrite content can be remarkably reduced, the green color of the fermented mustard is kept, the deterioration trend of the texture of the pickles is delayed, the flavor is enriched, and the quality of the fermented mustard is effectively improved. And a theoretical basis is provided for optimizing a fermented vegetable processing technology and researching and developing a fermented vegetable green processing technology.

Description

Technical Field

[0001] The present invention relates to the field of fermented vegetables, and in particular to a green preparation process for improving the quality of fermented mustard. Background Art

[0002] Fermented vegetables can be categorized into kimchi, salted vegetables, and pickled vegetables based on their processing techniques. Kimchi is primarily made by adding fresh vegetables to supplementary ingredients and then fermenting them in medium- to low-salt (2% to 10%) brine with microorganisms such as lactic acid bacteria. These vegetables are characterized by a tangy sour flavor, a crisp texture, and a delicate aroma. Mustard greens are the primary ingredient in kimchi, but industrially produced kimchi often suffers from excessive nitrite levels, discoloration, softening, and flavor changes.

[0003] Natural plant essential oils contain antioxidant and antibacterial active substances that can improve quality and enhance flavor. They have the potential to slow deterioration in fermented vegetable processing and serve as a green alternative to synthetic additives. Currently, some research is underway on the application of natural essential oils in fermented foods. For example, adding perilla essential oil to Sichuan pickles can enrich the content of volatile flavor compounds such as limonene and myrcene, giving the pickles a richer flavor. Adding snow chrysanthemum essential oil to smoked horse sausage can preserve the sausage's color and slow down product deterioration. Adding 0.05% grapefruit or citrus essential oil to wort can improve flavor and enhance product quality.

[0004] However, the green preparation methods in the prior art for reducing the nitrite content in fermented mustard, preventing color change, quality change, etc., and improving the quality of fermented mustard are not very effective. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a green preparation process for improving the quality of fermented mustard. By compounding lemon, citronella and nutmeg essential oils and applying them to fermented mustard, the nitrite content can be significantly reduced, the green color of the fermented mustard can be maintained, the deterioration trend of the kimchi texture can be delayed, and the flavor can be enriched, thereby effectively improving the quality of the fermented mustard.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The fermented mustard is composed of the following parts by mass: 500-600 parts of water, 300-400 parts of mustard, 40-60 parts of salt, 60-80 parts of white sugar and 0.05-0.1 part of compound essential oil.

[0008] Preferably, the compound essential oil is 0.05 parts by mass, and the compound essential oil includes the following components: lemon essential oil, citronella essential oil, and nutmeg essential oil.

[0009] Further preferably, the mass ratio of lemon essential oil, citronella essential oil and nutmeg essential oil in the compound essential oil is 1:3:3 or 3:1:3 or 1:1:1.

[0010] Most preferably, the mass ratio of the compound essential oils lemon essential oil, citronella essential oil and nutmeg essential oil is 1:1:1.

[0011] The green preparation process for improving the quality of fermented mustard greens described in the present invention comprises the following steps:

[0012] (1) Cleaning of mustard greens: Remove the yellowed and rotten parts of fresh mustard greens, wash them, dry them and set aside.

[0013] (2) Material and water preparation: Add sugar and salt to water in proportion and stir evenly to fully dissolve them. Then take an appropriate amount of solution and add the compound essential oil and stir thoroughly until the essential oil is completely dissolved in the water.

[0014] (3) Mustard fermentation: Add water to the mustard in proportion and ferment naturally at room temperature.

[0015] Preferably, the total amount of lemon essential oil, citronella essential oil and nutmeg essential oil in the compound essential oil in step (2) is 0.05 parts.

[0016] Most preferably, the mass ratio of lemon essential oil, citronella essential oil and nutmeg essential oil in the compound essential oil of step (2) is 1:1:1.

[0017] Preferably, the natural fermentation time at room temperature in step (3) is 30-40 days.

[0018] Most preferably, the natural fermentation time at room temperature in step (3) is 35 days.

[0019] The present invention also provides an application of the compound essential oil in a green preparation process of fermented mustard, which can effectively improve the quality of pickles.

[0020] The beneficial effects of the present invention are:

[0021] The present invention provides a green preparation process for improving the quality of fermented mustard. By synergistically compounding lemon essential oil, citronella essential oil and nutmeg essential oil, the nitrite content can be significantly reduced without affecting the normal fermentation of kimchi, the green color of the fermented mustard can be maintained, the deterioration trend of the kimchi texture can be delayed, the flavor can be enriched, and the quality of the fermented mustard can be effectively improved. DETAILED DESCRIPTION

[0022] The following examples are only intended to help understand the methods of the present invention and their core concepts. It should be noted that, for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications may be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The following description of the disclosed embodiments enables professionals in this field to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but may be applied to a wider range consistent with the principles and novel features disclosed herein. Although any methods and materials similar or equivalent to those described in the present invention may be used in the practice or testing of the present invention, preferred methods and materials are listed herein.

[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0024] Example 1

[0025] The green preparation process for improving the quality of fermented mustard is as follows:

[0026] The fermented mustard comprises the following components by weight: 600 parts of water, 300 parts of mustard, 40 parts of salt, 70 parts of sugar, and 0.05 parts of compound essential oil (the mass ratio of lemon essential oil, citronella essential oil, and nutmeg essential oil is 1:3:3).

[0027] (1) Cleaning of mustard greens: Remove the yellowed and rotten parts of fresh mustard greens, wash them, dry them and set aside.

[0028] (2) Material and water preparation: Add sugar and salt to water in proportion and stir evenly to fully dissolve them. Then take an appropriate amount of solution and add the compound essential oil and stir thoroughly until the essential oil is completely dissolved in the water.

[0029] (3) Mustard fermentation: Add water to mustard in proportion and ferment naturally at room temperature for 35 days.

[0030] Example 2

[0031] The green preparation process for improving the quality of fermented mustard is as follows:

[0032] The fermented mustard comprises the following components by weight: 600 parts of water, 300 parts of mustard, 40 parts of salt, 70 parts of sugar, and 0.05 parts of compound essential oil (the mass ratio of lemon essential oil, citronella essential oil, and nutmeg essential oil is 3:1:3).

[0033] (1) Cleaning of mustard greens: Remove the yellowed and rotten parts of fresh mustard greens, wash them, dry them and set aside.

[0034] (2) Material and water preparation: Add sugar and salt to water in proportion and stir evenly to fully dissolve them. Then take an appropriate amount of solution and add the compound essential oil and stir thoroughly until the essential oil is completely dissolved in the water.

[0035] (3) Mustard fermentation: Add water to mustard in proportion and ferment naturally at room temperature for 35 days.

[0036] Example 3

[0037] The green preparation process for improving the quality of fermented mustard is as follows:

[0038] The fermented mustard comprises the following components by weight: 600 parts of water, 300 parts of mustard, 40 parts of salt, 70 parts of sugar, and 0.05 parts of compound essential oil (the mass ratio of lemon essential oil, citronella essential oil, and nutmeg essential oil is 1:1:1).

[0039] (1) Cleaning of mustard greens: Remove the yellowed and rotten parts of fresh mustard greens, wash them, dry them and set aside.

[0040] (2) Material and water preparation: Add sugar and salt to water in proportion and stir evenly to fully dissolve them. Then take an appropriate amount of solution and add the compound essential oil and stir thoroughly until the essential oil is completely dissolved in the water.

[0041] (3) Mustard fermentation: Add water to mustard in proportion and ferment naturally at room temperature for 35 days.

[0042] control group

[0043] The fermented mustard is composed of the following components by weight: 600 parts of water, 300 parts of mustard, 40 parts of salt, 70 parts of sugar, and 0 part of compound essential oil.

[0044] The preparation method of fermented mustard is the same as that in Example 1.

[0045] Comparative Example 1

[0046] The fermented mustard comprises the following components by weight: 600 parts of water, 300 parts of mustard, 40 parts of salt, 70 parts of sugar, and 0.01 parts of compound essential oil (the mass ratio of lemon essential oil, citronella essential oil, and nutmeg essential oil is 1:1:1).

[0047] The preparation method of fermented mustard is the same as that in Example 1.

[0048] Comparative Example 2

[0049] The fermented mustard comprises the following components by weight: 600 parts of water, 300 parts of mustard, 40 parts of salt, 70 parts of sugar, and 0.1 part of a compound essential oil (the mass ratio of lemon essential oil, citronella essential oil, and nutmeg essential oil is 1:1:1).

[0050] The preparation method of fermented mustard is the same as that in Example 1.

[0051] Effect Examples

[0052] 1. Experimental methods:

[0053] Preparation of fermented mustard: Refer to NY / T 3340-2018 for pickling. Clean fresh mustard and place it in a pickle jar. Add salt, sugar, and compound essential oil to drinking water to prepare a mixture with a salt content of 4%, a sugar content of 7%, and 0.05-0.1‰ of compound essential oil. Add this mixture to the pickle jar at a mass ratio of 2:1. Ferment naturally for 35 days, and then take samples for measurement.

[0054] 2. Test methods for various indicators:

[0055] Nitrite index: Determination refers to GB 5009.33-2016 "National Food Safety Standard Determination of Nitrite and Nitrate in Food";

[0056] Color difference: A colorimeter was used in reflectance mode at 30 mm. Mustard leaf samples were placed in a special petri dish. The brightness (L*), red-green value (a*), and yellow-blue value (b*) were measured three times and the average value was calculated.

[0057] Texture Indicators: Mustard samples were cut into 2 cm × 2 cm pieces and subjected to the Total Texture Analysis (TPA) test using a texture analyzer. A TMS 10 mm cylindrical probe was used with the following parameters: test speed 60 mm / s, initial force 0.1 N, deformation index 50%, interval 5 seconds, and a programmable interval in the TPA-500N mode. Test parameters included hardness, cohesiveness, chewiness, springiness, and adhesiveness. Five measurements were performed on each sample, and the average value was obtained.

[0058] EXCEL 2016 was used to perform statistical analysis on the data.

[0059] 3. Experimental results:

[0060] (1) Nitrite index: According to the results in Table 1, the nitrite content in Examples 1-3 and Comparative Example 2 was significantly lower than that in the control group ( P <0.05), Example 3 and Comparative Example 2 were extremely significant ( P<0.01). During vegetable fermentation, bacteria on the surface of the vegetable raw materials reduce nitrates through assimilation or dissimilation, resulting in the production and accumulation of nitrites. The terpenes in lemon and nutmeg essential oils inhibit the formation of nitrites, while citronella essential oil has antibacterial and antiseptic properties. They can effectively inhibit the growth of bacteria with nitrate-reducing ability, thereby reducing nitrite production during vegetable fermentation, making the nitrite generation curve smoother and the peak lower, thereby improving the safety of kimchi during the dynamic fermentation process and at the end of fermentation.

[0061] Table 1 Effects of each preparation method on the nitrite content in samples

[0062] Group Nitrite content (35d) mg / kg Example 1 4.01 ± 0.26* Example 2 4.13 ± 0.19* Example 3 3.73 ± 0.15** Comparative Example 1 4.29 ± 0.17 Comparative Example 2 3.59 ± 0.14** control group 4.41 ± 0.22

[0063] Note: * indicates significant difference compared with the control group ( P <0.05, ** indicates a very significant difference compared with the control group ( P <0.01).

[0064] (2) Color difference index: According to the results in Table 2, the color difference index in Examples 1-3 and Comparative Example 2 is a * Value and b * The values ​​were significantly lower than those in the control group ( P <0.05), Examples 1-3 are extremely significant ( P <0.01). Mustard greens are turquoise in color at the beginning of fermentation, gradually turning golden yellow as fermentation progresses, followed by browning and yellowing, which affects their sensory quality. Appropriate concentrations of essential oils can regulate the activity of chlorophyll-degrading enzymes, slowing chlorophyll degradation and thus maintaining chlorophyll stability and inhibiting browning. Adding blended essential oils helps maintain the green color of mustard kimchi during the fermentation process.

[0065] Table 2 Effects of each preparation method on sample color

[0066] Group L* (lightness) a* (red and green) b* (yellow-blue) Example 1 16.74 ± 0.14* 1.76 ± 0.08** 13.42 ± 0.21** Example 2 18.22 ± 0.23* 2.25 ± 0.21** 15.31 ± 0.22** Example 3 16.58± 0.19* 1.12 ± 0.13** 11.33 ± 0.17** Comparative Example 1 22.39 ± 0.32 4.53 ± 0.19 23.19± 0.33 Comparative Example 2 18.74 ± 0.36* 3.98 ± 0.01* 14.45 ± 0.28** control group 21.06 ± 0.22 4.85 ± 0.27 24.42 ± 0.36

[0067] Note: * indicates significant difference compared with the control group ( P <0.05, ** indicates a very significant difference compared with the control group ( P <0.01).

[0068] (3) Texture index: Texture can reflect the changes in the softness, tissue structure and surface texture of kimchi, and is an important indicator of the quality of fermented vegetables. As shown in Table 3, during the 35-day fermentation process, the hardness, elasticity and chewiness of mustard kimchi changed to varying degrees. The hardness and elasticity of Example 3 were significantly higher than those of the control group (P <0.05), which can effectively maintain the integrity of kimchi cell walls, thereby delaying the softening trend of kimchi.

[0069] Table 3 Effects of each preparation method on sample texture

[0070] Example Hardness (N) Elasticity (mm) Chewing properties (mj) Example 1 30.24 ± 9.44 3.19 ± 0.65 31.03 ± 11.28 Example 2 31.46 ± 8.69 3.31 ±0.54 30.59 ± 10.62 Example 3 33.81 ± 9.83* 3.67 ± 1.04* 30.49 ± 12.16 Comparative Example 1 30.42 ± 5.49 3.03 ± 0.42 30.11 ± 9.22 Comparative Example 2 42.07 ± 14.82* 2.36 ± 0.50* 25.53 ± 9.71* control group 30.14 ± 6.67 3.23 ± 0.72 31.81 ± 12.04

[0071] Note: * indicates significant difference compared with the control group ( P <0.05)

[0072] In summary, the preparation methods of Examples 1-3 of the present invention can significantly reduce nitrite content, preserve the green color of mustard pickles, reduce yellowing, slow down the deterioration of pickle texture, and effectively improve the quality of fermented mustard. The preparation methods of the present invention can be promoted and applied in the industrial production of fermented mustard.

[0073] The above further describes the present invention in conjunction with specific embodiments. However, these embodiments are merely exemplary and do not limit the scope of the present invention in any way. It should be understood by those skilled in the art that the details and forms of the technical solutions of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, and such modifications and replacements shall fall within the scope of protection of the present invention.

Claims

1. A green preparation process for improving the quality of fermented mustard, characterized by The invention is prepared from the following raw materials in parts by weight: 500-600 parts of water, 300-400 parts of mustard, 40-60 parts of salt, 60-80 parts of white sugar and 0.05-0.1 part of compound essential oil.

2. The compound essential oil according to claim 1, wherein The invention comprises the following components: lemon essential oil, citronella essential oil and nutmeg essential oil, and the optimal addition amount of the compound essential oil is 0.05 parts.

3. The compound essential oil according to claim 2, wherein Calculated by mass, the optimal mass ratio of lemon essential oil, citronella essential oil and nutmeg essential oil is 1:1:

1.

4. A green preparation process for improving the quality of fermented mustard according to claims 1-3, characterized in that: The following steps are involved: (1) Cleaning of mustard greens: Remove the yellowed and rotten parts of fresh mustard greens, wash them, and dry them for later use; (2) Material and water preparation: Add sugar and salt to water in proportion and stir evenly to fully dissolve them. Then take an appropriate amount of solution and add the compound essential oil and stir thoroughly until the essential oil is completely dissolved in the water. (3) Mustard fermentation: Add water to the mustard in proportion and ferment naturally at room temperature.

5. The preparation method according to claim 5, characterized in that In the water of step (2), the salt content is 4-6%, the white sugar content is 6-8%, and the compound essential oil content is 0.05-0.1‰.

6. The preparation method according to claim 5, characterized in that In step (3), the mass ratio of water to mustard is 2:

1.

7. The preparation method according to claim 5, characterized in that The natural fermentation time in step (3) is 30-40 days.