Edible rose freezing, color-protecting and fresh-keeping formula and preparation method thereof

Abstract

The invention relates to the technical field of freezing, color protecting and fresh keeping of rose petals, and discloses a formula for freezing, color protecting and fresh keeping of edible rose petals and a preparation method of the formula. Comprising 40%-49% of malt syrup, 38%-49% of pineapple concentrated juice, 3%-7% of drinking water, 3%-5% of trehalose, 0.3%-0.5% of table vinegar, 0.3%-0.5% of locust bean gum, 0.3%-0.5% of hydroxy propyl distarch phosphate, 0.001%-0.003% of sodium tripolyphosphate, 0.0008%-0.002% of vitamin C and 0.003%-0.005% of natural spice for food. The prepared freezing color protection formula is reasonable in proportion, the problems of color fading, nutrition loss and cell disruption of rose petals in the freezing process can be reduced, water seepage and the like can be reduced, and the edible value of roses can be well maintained.

Description

Technical Field

[0001] The present invention relates to the technical field of food freezing and preservation, and protects an edible rose freezing color protection and preservation formula and its preparation method, in particular a freezing preservation formula and its preparation method that can effectively protect the color and quality of edible rose petals. Background Art

[0002] Yunnan is the kingdom of plants and a major flower province. In most areas, the sunshine time is long, the temperature is suitable, the air is clean, and the soil is pollution-free, which has unique natural advantages for growing various edible flowers. Among various flowers, the cultivation of edible roses is the most extensive. According to relevant research, edible roses contain a large amount of nutrients such as protein, amino acids, mineral elements, fat, total sugar, vitamin C, and crude fiber, and have good medicinal and health care values. With the rapid development of the food industry and the continuous improvement of requirements for health, nutrition, and quality, edible roses, as natural raw materials with high nutritional value, have gradually been widely used in the food industry. Their unique flower color, aroma, and nutritional components make them ideal raw materials for making a variety of foods, including instant roses, rose tea, rose jam, and rose cakes. However, in actual applications, the nutrients in rose petals are easily affected by the external environment and decompose or become ineffective, and at the same time, their bright rose color is also easily degraded during the processing process, affecting the quality and taste of the products.

[0003] As an effective food preservation method, freezing technology is widely used in various food preservation fields because it can effectively control the growth of microorganisms in food, extend the shelf life of products, and maintain the color, aroma, and taste of food. However, in actual applications, directly freezing fresh rose petals may cause the rose color to decompose and fade, resulting in obvious quality loss, thus affecting its stability as a raw material. Patent No. CN202311069093.9 discloses a fresh flower freezing and preservation method, which sprays a honey aqueous solution evenly on the surface of fresh flowers; prepares a low-molecular liquid, prepares a critical solution by mixing the low-molecular liquid, and makes a locking agent according to the critical solution; sprays the locking agent evenly on each part of the fresh flower for locking state preservation. Patent No. CN202211201814.2 discloses a litchi semi-freezing color protection and preservation process, in which litchi is soaked in a color protection mixture of 1-4% edible hydrochloric acid + 2-8% oxalic acid + 0.1-0.5% isoascorbic acid + 0.1-0.5 g / L natamycin for 1-5 minutes, which can maintain the color of litchi peel and the taste and flavor of the pulp. Patent CN202410044200.0 discloses a composite color protection and crispness preservation agent, the components of which are 1 wt.% - 2 wt.% citric acid, 1 wt.% - 2 wt.% ascorbic acid, 0.5 wt.% - 1 wt.% ferulic acid, and 1 wt.% - 2 wt.% calcium chloride, and the rest is water, which improves the quality of frozen pickled apple slices.

[0004] After retrieval, there is no existing freezing preservation formula in the prior art that can effectively protect the color and quality of edible rose petals, solve the problems of color loss, nutrient loss, and cell breakage during the freezing process of edible roses, and ensure the freezing quality of edible roses. Due to the extremely thin cell walls, easy degradation of anthocyanins, and strong thermosensitivity of essential oils in edible roses, its freezing preservation faces special problems such as color attenuation, nutrient loss, and cell breakage. Existing fruit and vegetable freezing technologies are difficult to meet the requirements due to poor adaptability of color protectants, insufficient ice crystal control, and lack of flavor protection. There is an urgent need to develop a compound formula of natural color-protecting freezing agents to solve the core quality indicators such as color, cell breakage, and loss of nutritional flavor during its freezing process, and ensure its commercial value as a high-value agricultural product. Summary of the Invention

[0005] To overcome this technical difficulty, the present invention proposes a color-protecting preservation formula based on freezing technology and its preparation method.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An antifading and fresh-keeping solution for freezing edible rose petals, the fresh-keeping solution comprising the following raw materials: by mass concentration, maltose syrup 40 - 49%, pineapple concentrated juice 38 - 49%, drinking water 3 - 7%, trehalose 3 - 5%, vinegar 0.3 - 0.5%, locust bean gum 0.3 - 0.5%, hydroxypropyl distarch phosphate 0.3 - 0.5%, sodium tripolyphosphate 0.001 - 0.003%, vitamin C 0.0008 - 0.002%, natural food flavor 0.003 - 0.005%, and the concentration of the pineapple concentrated juice is above 80%.

[0008] Preferably, the fresh-keeping solution comprises the following raw materials: by mass concentration, maltose syrup 46.42%, pineapple concentrated juice 44.14%, drinking water 4.08%, trehalose 4.05%, vinegar 0.44%, locust bean gum 0.43%, hydroxypropyl distarch phosphate 0.42%, sodium tripolyphosphate 0.0018%, vitamin C 0.0012%, and natural food flavor 0.004%.

[0009] The present invention also protects a preparation method for frozen edible rose petals, comprising the following steps:

[0010] S1 Raw material screening: Select fresh edible roses with bright colors, no pests, diseases, and mechanical damage;

[0011] S2 Cleaning and pretreatment: Wash with sterile water, and the cleaning environmental temperature is 4°C;

[0012] S3 Immersion treatment with the fresh-keeping solution: Immerse and treat with the fresh-keeping solution as described in claim 1 or 2 for 3 - 5 minutes, and the temperature is 4 ± 1°C;

[0013] For the S4 freezing treatment, the soaked rose flowers are frozen at -40°C to -35°C in a fluidized bed freezer with a refrigeration machine air speed of 5 - 8 m / s and a freezing time of 10 - 15 minutes.

[0014] Furthermore, the steps for preparing the preservative solution are as follows:

[0015] S11 Weigh all the raw materials as described in Claim 1 or 2. First, add 50 - 70% drinking water to the stirring tank, start low-speed stirring, and sequentially add maltose syrup and pineapple concentrate, and stir until completely mixed to obtain a basic solution;

[0016] S12 Dissolve locust bean gum with 60 - 70°C hot water, gelatinize hydroxypropyl distarch phosphate with 70 - 80°C hot water, then add trehalose and mix evenly, and slowly sprinkle it into the basic solution obtained in S11 that is being stirred, and stir at high speed for 10 - 15 minutes until completely dissolved;

[0017] S13 Dissolve sodium tripolyphosphate in drinking water, make a solution and add it to the stirring tank, and stir at low speed for 5 minutes; then slowly add vinegar while monitoring the pH value to 3.8 - 4.2, and stir until uniform;

[0018] S14 Dissolve vitamin C in drinking water, add it to the tank and stir for 3 minutes, then add natural food flavor, and stir at low speed until uniform to avoid aroma volatilization, add drinking water to make up to 100% of the total mass, and homogenize at high speed at 20 - 30 MPa for 2 minutes to ensure uniform dispersion of particles.

[0019] The acidity (pH ≈ 3.5) of pineapple juice and vinegar in the formula may affect the system stability. Sodium tripolyphosphate can be used to adjust the pH to 3.8 - 4.2 to inhibit microorganisms and balance the taste and maintain the flavor. Preparing the preservative solution according to the above can ensure the uniformity and stability of the system, avoid caking of thickeners and destruction of the colloid structure by acidic substances, and at the same time retain the activity of vitamin C and flavorings. At the same time, vitamin C needs to be added in the dark and at low temperature to prevent oxidation and browning of pineapple juice.

[0020] Furthermore, the rose petals selected are those in a semi-open state that have not fully unfolded and are harvested at 8:00 - 10:00 in the morning on a sunny day. The rose petals in a semi-open state that have not fully unfolded have a strong aroma and relatively tough texture. Fully open flowers are easily frostbitten. They are harvested after the morning dew has completely evaporated (8:00 - 10:00). At this time, the petal water content is low and the aroma substance content is high. Avoid picking during rainy days or high-temperature periods to prevent mold growth and cell rupture.

[0021] Further, after washing with sterile water in step S2, it is necessary to soak in sodium hypochlorite solution with an available chlorine content of 50-100 ppm or use clear water + 0.5-1% edible salt + 0.1% baking soda for 5-10 minutes, and gently stir to kill surface microorganisms.

[0022] In the formula of the present invention, a color protection synergistic system, a thickening and stabilizing system, an anti-corrosion synergistic system, a flavor protection system, and an antioxidant synergistic system jointly ensure the color protection, freshness preservation, and nutrition retention of edible roses. The pineapple concentrate, vinegar, and vitamin C constitute a color protection synergistic system to form an acidic environment to inhibit browning.

[0023] In the present invention, the pineapple concentrate (38-49%) contains natural organic acids (citric acid, malic acid), which reduces the system pH to 3.5-4.5, inhibiting the activity of polyphenol oxidase. Vinegar (0.3-0.5%): supplements acetic acid, further reducing the pH to 3.0-3.5, forming a composite acid environment with pineapple juice to enhance the color protection effect. Vitamin C (0.0008-0.002%): as a reducing agent, reacts with oxygen preferentially to prevent the oxidation and fading of pigments (carotenoids in pineapple and anthocyanins in roses). Synergistic point: the stability of vitamin C is improved under acidic conditions, and the color protection efficiency is increased by 30-50% compared with using it alone. Using vitamin C in synergy with sodium tripolyphosphate enhances the chelating ability through hydroxyl coordination, especially for Fe 3+ The chelating rate of is increased by more than 2 times. Sodium tripolyphosphate contains chelated iron and copper ions, forming soluble complexes to prevent metal ion-catalyzed oxidation reactions.

[0024] Using locust bean gum, hydroxypropyl distarch phosphate, and malt syrup to form a composite gel network, and jointly with trehalose to form a thickening and stabilizing system. Locust bean gum and hydroxypropyl distarch phosphate form a hydrogen bond network, which is stable under neutral to acidic conditions, and the viscosity is increased by 5-8 times. The high-concentration sugar solution of malt syrup generates a high osmotic pressure, reducing the water activity. At the same time, as a plasticizer, it prevents the colloid from being brittle. The galactomannan of locust bean gum and the branched structure of starch phosphate are intertwined to form a three-dimensional network structure to prevent water migration. The high sugar content of malt syrup inhibits the excessive cross-linking between colloid molecules, avoiding the gel from being too hard. In a high-concentration sugar system (the total concentration of malt syrup + trehalose ≥ 45%), trehalose forms an amorphous glassy state, encapsulating the aromatic substances and vitamin C in pineapple juice to prevent crystal damage during freezing or drying. Synergistic with locust bean gum, it raises the glass transition temperature (Tg) of the system to 50-60°C, making it more stable for storage at room temperature.

[0025] Through a multi-dimensional antibacterial and antiseptic synergistic system of acidic environment, high sugar, and natural spices in the formula. In the formula, pineapple juice and vinegar make the pH < 4.0, inhibiting acid-intolerant bacteria such as Escherichia coli and Salmonella. High osmotic pressure: the total concentration of maltose syrup and trehalose ≥ 45%, Aw ≤ 0.85, inhibiting the growth of yeasts and molds. Natural spices: If containing cloves, cinnamon, etc., their volatile oil components (such as eugenol) damage the microbial cell membrane and, in synergy with the acidic environment, expand the diameter of the antibacterial zone by 1.5 times.

[0026] The flavor protection system mainly includes aroma fixation and is mainly composed of maltose syrup, trehalose, pineapple juice, vinegar, and vitamin C. In the formula of the present invention, maltose syrup (sweet) provides a long-lasting sweetness, masking the sharp sour taste of vinegar. Trehalose has a mild sweetness, and when compounded with maltose syrup, the sweetness reaches 80% of sucrose, while reducing the overall sugar calories. Pineapple juice and vinegar form a golden ratio of 10:1 - 15:1 in terms of sweet and sour, achieving a sweet and sour balance and enhancing the flavor layer. High sugar, colloid, and natural spices can fix the aroma. The high-viscosity sugar solution formed by maltose syrup and trehalose encapsulates volatile aroma substances (such as esters in pineapple), reducing volatilization loss. Locust bean gum and starch phosphate form a microcapsule structure, slowly releasing the aroma and extending the fragrance retention time by 2 - 3 times. Natural spices supplement the characteristic aroma and mask possible off-flavors (such as the sour and astringent taste of vinegar).

[0027] Vitamin C and natural food spices in the formula constitute an antioxidant synergistic system. The spices contain rosemary, tea polyphenols, etc., providing fat-soluble antioxidant components, scavenging fat-soluble free radicals, forming a dual antioxidant barrier with vitamin C, and synergistically improving the total antioxidant capacity.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The freezing and preservation formula of the present invention can effectively reduce the impact of freezing on rose petals through optimized ratios, maintaining their bright color, rich nutritional components, and stable quality. The present invention can not only effectively extend the preservation period of fresh rose raw materials but also reduce the problem of product quality decline caused by discoloration or nutrient loss of the raw materials during the freezing process. This formula can achieve excellent protection effects in terms of color protection, viscosity stability, antioxidant, and antiseptic properties, and is applicable to scenarios such as fruit juice beverages, sauces, and baking fillings. Description of the Drawings

[0030] Figure 1 Appearance quality of frozen and thawed petals under color protection formulas with different ratios.

[0031] Figure 2 Effects of color protection and preservation solution on the contents of anthocyanins and total flavonoids in rose petals.

[0032] Figure 3 Effects of color protection and preservation solution on the relative conductivity of rose petals. Specific Embodiments

[0033] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be noted here that the description of these embodiments is used to help understand and verify the present invention, but does not constitute a limitation on the present invention.

[0034] Effect of Different Color Retention and Freshness Preservation Formulas on Edible Roses in Examples

[0035] A freezing color retention and freshness preservation liquid for edible rose petals, the preservation liquid comprising the following raw materials: by mass concentration, maltose syrup 40 - 49%, pineapple concentrated juice 38 - 49%, drinking water 3 - 7%, trehalose 3 - 5%, vinegar 0.3 - 0.5%, locust bean gum 0.3 - 0.5%, hydroxypropyl distarch phosphate 0.3 - 0.5%, sodium tripolyphosphate 0.001 - 0.003%, vitamin C 0.0008 - 0.002%, natural food flavor 0.003 - 0.005%, and the concentration of the pineapple concentrated juice is above 80%.

[0036] The preparation steps of the preservation liquid are as follows:

[0037] S11 Weigh all raw materials according to the above formula. First, add 50 - 70% of the drinking water to the stirring tank, start low-speed stirring, and sequentially add maltose syrup and pineapple concentrated juice, and stir until completely mixed to obtain a basic solution;

[0038] S12 Dissolve locust bean gum with hot water at 60 - 70°C, gelatinize hydroxypropyl distarch phosphate with hot water at 70 - 80°C, then add trehalose and mix evenly, and slowly add it to the basic solution obtained in S11 while stirring, and stir at high speed for 10 - 15 minutes until completely dissolved;

[0039] S13 Dissolve sodium tripolyphosphate in drinking water, make a solution and add it to the stirring tank, stir at low speed for 5 minutes; then slowly add vinegar, and monitor the pH value to 3.8 - 4.2 while stirring until uniform;

[0040] S14 Dissolve vitamin C in drinking water, add it to the tank and stir for 3 minutes, then add natural food flavor, stir at low speed until uniform (to avoid aroma volatilization), add drinking water to make the total mass 100%, and homogenize at high speed at 20 - 30 MPa for 2 minutes to ensure uniform dispersion of particles. At the same time, vitamin C needs to be added in the dark and at low temperature to prevent oxidation and browning of pineapple juice.

[0041] pH Control: The acidity of pineapple juice and vinegar (pH ≈ 3.5) may affect the system stability. It can be adjusted to pH 3.8 - 4.2 with sodium tripolyphosphate to inhibit microorganisms, achieve a balanced taste, and maintain the flavor. Preparing the preservation liquid as described above can ensure the uniformity and stability of the system, prevent thickeners from caking and acidic substances from destroying the colloid structure, and retain the activity of vitamin C and spices at the same time.

[0042] Preparation method of frozen edible rose petals using the above-prepared preservation liquid, including the following steps:

[0043] S1 Raw material screening: Select fresh edible roses with bright colors, no pests, diseases, and mechanical damage; the rose petals are selected as those in a semi-open state that have not fully unfolded, and are harvested at 8:00 - 10:00 in the morning on sunny days. Rose petals in a semi-open state that have not fully unfolded have a strong aroma and relatively tough texture. Fully open flowers are prone to frostbite. They are harvested after the morning dew has completely evaporated (8:00 - 10:00). At this time, the water content of the petals is low and the content of aroma substances is high. Avoid picking during rainy days or high-temperature periods to prevent mold growth and cell rupture;

[0044] S2 Cleaning and pretreatment: Wash with sterile water, and then soak in sodium hypochlorite solution with an available chlorine content of 50 - 100 ppm or use clear water + 0.5 - 1% edible salt + 0.1% baking soda for 5 - 10 minutes, gently stir to kill surface microorganisms, and the cleaning environment temperature is 4°C;

[0045] S3 Preservation liquid soaking treatment: Soak with the above preservation liquid for 3 - 5 minutes; the soaking temperature is 4 ± 1°C;

[0046] S4 Freezing treatment: Use a fluidized bed quick-freezing machine for the soaked roses: at -40°C - -35°C or below, the wind speed of the refrigerator is 5 - 8 m / s, and the freezing time is 10 - 15 minutes. Then store at -18°C.

[0047] The test thawing method of the present invention is slow thawing at 4°C, and the thawing time is 18 h. Conventional freezing color protectants and no color protectant are used as comparative examples (Table 1). Except for the different color protection and preservation liquids, the remaining steps are the same.

[0048] Table 1 Different color protection and preservation formula tables

[0049]

[0050] Analysis of test results

[0051] Table 2 Effects of different color protection and preservation liquids on the color of rose petals

[0052] Example 1 Example 2 Example 3 Comparative Example 1 L value 24.47±0.45 23.65±0.54 22.37±0.41 22.55±0.39 a value 19.13±0.58b 22.99±1.25a 21.93±1.30a 19.13±1.24b b value -4.71±0.24 -1.74±0.22 -0.72±0.62 -3.12+0.26 ΔE value 2.49 4.24 3.69

[0053] Note: The ΔE value is calculated based on Comparative Example 1

[0054] In the table, the L value (lightness axis) ranges from 0 (black) to 100 (white), representing the light and dark degree of the color; the a value (red - green axis) represents the offset of the color in the red - green direction, a > 0: tending towards red; a < 0: tending towards green; the b value (yellow - blue axis) represents the offset of the color in the yellow - blue direction, b > 0: tending towards yellow; b < 0: tending towards blue.

[0055] The results are as Figure 1 shown in and Table 2. Compared with Comparative Examples 1 and 2, the color - protecting and freshness - preserving liquids with three different ratios in Examples 1 - 3 can all better maintain the color of rose petals before and after freezing from the appearance, reducing the phenomenon of color darkening during freezing and thawing. Among Examples 1 - 3, the effect of Example 2 is the best. After thawing, the color is bright and keeps the original color of the rose. Among the remaining 4 examples and comparative examples, the color darkens to varying degrees after thawing. Among them, Comparative Examples 1 and 2 have lost the due color of the rose, and the commercial property has decreased.

[0056] The results of color difference measurement show that:

[0057] Example 2 has the largest a value. The larger the a value, the more the petal color tends towards red, indicating that its red chroma is the most obvious and it better maintains the original red color of the rose. The ΔE value further shows that the color differences of the three implementation cases can all show a distinguishable difference from the comparison cases to the human eye. The difference between Example 2 and the comparison cases is the largest (4.24), and the difference can be clearly seen with the naked eye, indicating that the color - protecting and freshness - preserving liquid can reduce the loss of the color of rose petals and has the best effect.

[0058]

[0059] Meaning: It represents the degree of difference between two colors.

[0060] ΔE < 1: The human eye can hardly detect the difference;

[0061] ΔE = 2 - 3: Slight difference can be detected (common threshold in the food industry);

[0062] ΔE > 5: The colors are significantly different. Anthocyanins and total flavonoids are important nutrients in roses, and the content of anthocyanins is more closely related to the color of rose petals. As Figure 2As shown in the figure, the measurement results indicate that the contents of anthocyanins and total flavonoids in the rose petals treated with the color protection and freshness preservation solution are significantly higher than those in Comparative Example 1 after thawing. Among them, the contents of anthocyanins and total flavonoids in Example 2 are increased by 41.6% and 39.1% respectively compared with those in Example 1, indicating that the present invention can effectively reduce the nutrient loss of frozen rose petals. At the same time, the relatively high anthocyanins and total flavonoids have strong antioxidant capabilities, enhancing their resistance to the adversity caused by low-temperature freezing and thawing, reducing cell membrane oxidation, lowering cell permeability, better maintaining cell integrity, maintaining the anthocyanin content, and preserving good color, flavor and nutrition.

[0063] As Figure 3 shown in the figure, the measurement results of conductivity indicate that the relative conductivity of Example 2 of the present invention is the lowest, and the relative conductivities of Example 1 and Example 3 are both lower than that of Comparative Example 1, indicating that the method of the present invention can reduce the degree of cell damage during the freezing process, reduce the leakage of cell contents, and maintain good appearance, flavor and nutrition.

[0064] Therefore, an edible rose freezing color protection and freshness preservation formula provided by the present invention can reduce problems such as fading of rose petal color, nutrient loss and cell breakage during the freezing process, and preferably maintain the edible value of roses.

Claims

1. A formula for freezing and preserving the color of edible rose petals, characterized in that: The fresh-keeping formula comprises the following raw materials: measured by mass concentration, 40-49% of maltose syrup, 38-49% of pineapple concentrated juice, 3-7% of drinking water, 3-5% of trehalose, 0.3-0.5% of vinegar, 0.3-0.5% of locust bean gum, 0.3-0.5% of hydroxypropyl distarch phosphate, 0.001-0.003% of sodium tripolyphosphate, 0.0008-0.002% of vitamin C, and 0.003-0.005% of natural food flavoring, and the concentration of the pineapple concentrated juice is above 80%.

2. A formula for freezing and protecting the color of edible rose petals according to claim 1, characterized in that: The fresh-keeping formula comprises the following raw materials: measured by mass concentration, 46.42% of maltose syrup, 44.14% of pineapple concentrated juice, 4.08% of drinking water, 4.05% of trehalose, 0.44% of vinegar, 0.43% of locust bean gum, 0.42% of hydroxypropyl distarch phosphate, 0.0018% of sodium tripolyphosphate, 0.0012% of vitamin C and 0.004% of natural food flavoring.

3. A method for preparing frozen edible rose petals, comprising the following steps: S1 Raw material screening: Select fresh edible roses with bright colors, free of pests and mechanical damage; S2 cleaning pretreatment uses sterile water for cleaning, and the cleaning environment temperature is 4°C; S3: Soaking in the fresh-keeping solution: Soaking in the fresh-keeping solution prepared by the fresh-keeping formula as described in claim 1 or 2 for 3-5 minutes at a temperature of 4±1°C; S4 Freezing Treatment: The soaked roses are quickly frozen in a fluidized bed freezer at -40°C to 35°C, with a wind speed of 5-8m / s for 10-15 minutes, and then stored at -18°C.

4. The method for preparing frozen edible rose petals according to claim 3, characterized in that The preparation steps of the fresh-keeping solution are as follows: S11 Weigh all the raw materials as described in claim 1 or 2, first add 50-70% of drinking water into a stirring tank, start low-speed stirring, add maltose syrup and pineapple concentrated juice in sequence, and stir until completely mixed to obtain a basic solution; S12 uses 60-70℃ hot water to dissolve locust bean gum, and 70-80℃ hot water to dissolve hydroxypropyl distarch phosphate for gelatinization, then add trehalose and mix well, then slowly sprinkle into the basic solution obtained in S11 while stirring, and stir at high speed for 10-15 minutes until it is completely dissolved; S13: dissolving sodium tripolyphosphate in drinking water to prepare a solution, adding the solution into a stirring tank, stirring at a low speed for 5 minutes; then slowly adding vinegar, monitoring the pH value to 3.8-4.2, and stirring until uniform; S14 Dissolve vitamin C in drinking water at low temperature and away from light, add to a tank and stir for 3 minutes, then add natural food spices, stir at low speed until uniform, add drinking water to the total mass of 100%, and homogenize at high speed at 20-30MPa for 2 minutes.

5. The method for preparing frozen edible rose petals according to claim 3, characterized in that: The rose petals in step S1 are petals that are half-opened and not fully unfolded, and are harvested between 8:00 and 10:00 in the morning on a sunny day.

6. The method for preparing frozen edible rose petals according to claim 3, characterized in that: After the sterile water washing in the step S2, it is necessary to soak in a sodium hypochlorite solution with an effective chlorine content of 50-100 ppm or clean water + 0.5-1% edible salt + 0.1% baking soda for 5-10 minutes and stir gently.

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