Baganden coconut milk pastry and preparation method thereof

Abstract

The invention belongs to the technical field of pastry preparation, and particularly relates to a gorgeous coconut milk pastry and a preparation method thereof. According to the preparation method of the multicoloured powder, multicoloured leaves are soaked in lactobacillus plantarum liquid, then airing, drying and smashing are conducted, and tocopherol, tea polyphenol, lactococcus lactis liquid and lactobacillus rhamnosus liquid are added for aerobic fermentation, so that organic substances in the multicoloured leaves are decomposed by microorganisms, and the multicoloured powder is obtained; more aroma components are released, pigment components are stabilized, and the release of bioactive components in the multicoloured powder is also facilitated. Therefore, the gorgeous coconut milk pastry prepared by mixing the gorgeous powder prepared by the technical scheme with the eggs, the flour, the coconut milk, the oil and other raw materials is good in flavor, attractive in appearance and high in nutritional value.

Description

Technical Field

[0001] The present invention belongs to the technical field of pastry preparation, and particularly relates to a pandan coconut milk pastry and a preparation method thereof. Background Art

[0002] Pandanus amaryllifolius Roxb., also known as pandan leaf, vanilla leaf, fragrant screw pine, etc., is a perennial evergreen herb. The pandan leaf is slender and sword-shaped, with a dark green color, having certain ornamental value and can be planted as a courtyard plant; in addition, the pandan leaf juice is rich in antioxidant components, having the effects of relieving summer heat, calming the nerves, clearing away heat and removing dampness, and relaxing muscles and activating collaterals. Moreover, the leaf has a unique natural fragrance, which can add a fresh and sweet taste to food, so the application range of pandan is relatively wide.

[0003] Although pandan powder is made from pandan, the preparation methods are quite different. For example, in Chinese Patent CN 112516249A, the pandan leaf juice is pre-frozen, freeze-dried, sublimation-dried, and desorption-dried to obtain pandan powder, which has the effect of reducing blood lipid, but the preparation method is relatively cumbersome; while conventional drying methods such as drying and freeze-drying are not conducive to the retention of the aroma and color of pandan powder, thus limiting its application in food. Summary of the Invention

[0004] The purpose of the present invention is to provide a pandan coconut milk pastry and a preparation method thereof, wherein the preparation of pandan powder is simple, with strong aroma and bright color, and the pandan coconut milk pastry is beautiful and nutritious.

[0005] The present invention provides a preparation method of pandan powder, comprising the following steps:

[0006] Soaking pandan leaves in a Lactobacillus plantarum bacterial solution to obtain pretreated pandan leaves;

[0007] Successively sun-drying, drying, and pulverizing the pretreated pandan leaves to obtain a pulverized material;

[0008] Mixing the pulverized material, antioxidant, compound bacterial solution, and water, and then performing aerobic fermentation to obtain a fermentation broth;

[0009] Successively centrifuging and filtering the fermentation broth to obtain pandan juice;

[0010] Performing spray drying on the pandan juice to obtain pandan powder;

[0011] The compound bacterial solution is composed of a Lactococcus lactis bacterial solution and a Lactobacillus rhamnosus bacterial solution;

[0012] The antioxidant is composed of tocopherol and tea polyphenol according to a mass ratio of 1:0.5 - 0.7.

[0013] Preferably, when soaking pandan leaves in the Lactobacillus plantarum bacterial liquid, the effective viable count of the Lactobacillus plantarum bacterial liquid ≥ 1×10 7 cfu / mL;

[0014] The soaking time is 1 - 2 min.

[0015] Preferably, the volume ratio of the Lactococcus lactis bacterial liquid to the Lactobacillus rhamnosus bacterial liquid in the compound bacterial liquid is 1:1.5 - 2;

[0016] The effective viable counts of the Lactococcus lactis bacterial liquid and the Lactobacillus rhamnosus bacterial liquid are 1×10 7 -2×10 7 cfu / mL.

[0017] Preferably, the drying in the sun includes: exposing the pandan leaves sprayed with the Lactobacillus plantarum bacterial liquid to the natural environment under sunlight for 6 - 8 h;

[0018] The drying includes: the temperature is 35 - 40 °C and the time is 40 - 50 min.

[0019] Preferably, the mass ratio of the pulverized matter, antioxidant, compound bacterial liquid and water is 1:0.02 - 0.03:0.035 - 0.05:5 - 8;

[0020] The temperature of the aerobic fermentation is 27 - 30 °C and the time is 5 - 7 d.

[0021] Preferably, the centrifugation speed is 1000 - 1500 rpm; the centrifugation time is 15 - 20 min.

[0022] The present invention provides the pandan powder obtained by the preparation method described in the above technical solution.

[0023] The present invention provides the application of the pandan powder described in the above technical solution in food.

[0024] The present invention provides a pandan coconut milk pastry, which comprises the following raw materials in parts by mass: 18 - 20 parts of eggs, 4.5 - 5 parts of flour, 1 - 1.5 parts of the pandan powder described in the above technical solution, 3.5 - 4 parts of coconut milk, 2.5 - 3 parts of oil, 0.2 - 0.3 parts of baking powder and 1.5 - 2 parts of sugar.

[0025] The present invention provides a preparation method of the pandan coconut milk pastry described in the above technical solution, which comprises the following steps:

[0026] Separate the egg yolks and egg whites in the eggs for later use;

[0027] Add oil, coconut milk, flour, pandan powder and baking powder to the egg yolks in sequence and stir evenly to obtain a mixture;

[0028] Mix and beat the egg white and sugar to obtain meringue;

[0029] Mix the mixture with the meringue and then bake to obtain pandan coconut milk pastries.

[0030] Beneficial effects:

[0031] The present invention provides a method for preparing pandan powder. By soaking pandan leaves in a Lactobacillus plantarum bacterial solution, followed by sun drying, drying, and pulverizing, and adding tocopherol, tea polyphenols, a Lactococcus lactis bacterial solution, and a Lacticaseibacillus rhamnosus bacterial solution for aerobic fermentation, it is beneficial for microorganisms to decompose organic substances in pandan leaves, releasing more aroma components, and at the same time making the color of the pandan powder more vivid and lasting; in addition, the method provided by the present invention can also release bioactive components in the pandan powder and assist in enhancing the aroma and flavor of the pandan powder.

[0032] Based on the above technical advantages, the present invention also provides the application of the pandan powder described in the above technical solution in food. By mixing the pandan powder prepared by the present invention with raw materials such as eggs, flour, coconut milk, and oil to prepare coconut milk pastries, not only the flavor and appearance of the pastries are improved, but also the nutritional value of the pastries is enriched. Specific embodiments

[0033] In the present invention, unless otherwise specified, the raw materials, equipment, and methods used are all conventional selections.

[0034] To further illustrate the present invention, the following describes in detail the solution provided by the present invention in combination with embodiments, but they cannot be understood as limiting the protection scope of the present invention.

[0035] Example 1

[0036] A method for preparing pandan powder, the steps are as follows:

[0037] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0038] Soak the dried pandan leaves in a Lactobacillus plantarum bacterial solution with an effective viable count of 1×10 7 cfu / mL for 2 min to obtain soaked pandan leaves;

[0039] Under a natural environment exposed to sunlight, sun dry the soaked pandan leaves for 6 h, then dry them at 38°C for 40 min, and pulverize the pandan leaves after drying to obtain a pulverized product (the particle size of the pulverized product can be <1 cm);

[0040] (2) Mix tocopherol and tea polyphenols evenly according to a mass ratio of 1:0.5 to obtain an antioxidant for standby.

[0041] Mix the Lactococcus lactis bacterial liquid and the Lactobacillus rhamnosus bacterial liquid with an effective viable count of 1×10 7 cfu / mL evenly according to a volume ratio of 1:1.5 for standby.

[0042] (3) Mix the above-mentioned crushed material, antioxidant, compound bacterial liquid and water evenly according to a mass ratio of 1:0.02:0.035:8, and carry out aerobic fermentation at 27°C for 7 days to obtain a fermentation broth.

[0043] Centrifuge the fermentation broth at 1200 rpm for 15 minutes, take the supernatant for filtration, and the obtained filtrate is pandan juice.

[0044] Carry out spray drying on the pandan juice to obtain pandan powder.

[0045] Example 2

[0046] A method for preparing pandan powder, the steps are as follows:

[0047] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves.

[0048] Soak the dried pandan leaves in a Lactobacillus plantarum bacterial liquid with an effective viable count of 1×10 7 cfu / mL for 2 minutes to obtain soaked pandan leaves.

[0049] Under the natural environment exposed to sunlight, dry the soaked pandan leaves for 6 hours, then dry them at 38°C for 40 minutes, and crush the pandan leaves after drying to obtain a crushed material (the particle size of the crushed material can be <1 cm).

[0050] (2) Mix tocopherol and tea polyphenols evenly according to a mass ratio of 1:0.7 to obtain an antioxidant for standby.

[0051] Mix the Lactococcus lactis bacterial liquid and the Lactobacillus rhamnosus bacterial liquid with an effective viable count of 2×10 7 cfu / mL evenly according to a volume ratio of 1:1.5 for standby.

[0052] (3) Mix the above-mentioned crushed material, antioxidant, compound bacterial liquid and water evenly according to a mass ratio of 1:0.02:0.035:8, and carry out aerobic fermentation at 27°C for 7 days to obtain a fermentation broth.

[0053] Centrifuge the fermentation broth at 1200 rpm for 15 minutes, take the supernatant for filtration, and the obtained filtrate is pandan juice.

[0054] The pandan juice is spray-dried to obtain pandan powder.

[0055] Example 3

[0056] A method for preparing pandan powder, the steps are as follows:

[0057] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0058] The dried pandan leaves are soaked in a Lactobacillus plantarum bacterial solution with an effective viable count of 1×10 7 cfu / mL for 2 min to obtain soaked pandan leaves;

[0059] Under a natural environment exposed to sunlight, the soaked pandan leaves are sun-dried for 6 h, then dried at 38 °C for 40 min, and after drying, the pandan leaves are crushed to obtain a crushed product (the particle size of the crushed product can be <1 cm);

[0060] (2) Mix tocopherol and tea polyphenols evenly according to a mass ratio of 1:0.5 to obtain an antioxidant, and set it aside;

[0061] Mix a Lactococcus lactis bacterial solution and a Lactobacillus rhamnosus bacterial solution with an effective viable count of 1×10 7 cfu / mL evenly according to a volume ratio of 1:2, and set it aside;

[0062] (3) Mix the above-mentioned crushed product, antioxidant, compound bacterial solution and water evenly according to a mass ratio of 1:0.02:0.05:6, and carry out aerobic fermentation at 27 °C for 7 d to obtain a fermentation broth;

[0063] Centrifuge the fermentation broth at 1200 rpm for 15 min, take the supernatant for filtration, and the obtained filtrate is pandan juice;

[0064] The pandan juice is spray-dried to obtain pandan powder.

[0065] Comparative Example 1

[0066] A method for preparing pandan powder, the steps are as follows:

[0067] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0068] The dried pandan leaves are soaked in a Lactobacillus plantarum bacterial solution with an effective viable count of 1×10 7 cfu / mL for 2 min to obtain soaked pandan leaves;

[0069] Under a natural environment exposed to sunlight, the soaked pandan leaves are sun-dried for 6 h, then dried at 38 °C for 40 min, and after drying, the pandan leaves are crushed to obtain a crushed product (the particle size of the crushed product can be <1 cm);

[0070] (2) Mix the Lactococcus lactis liquid and Lactobacillus rhamnosus liquid with an effective viable count of 1×10 7 cfu / mL evenly at a volume ratio of 1:1.5, and set aside for later use;

[0071] (3) Mix the above-mentioned crushed material, compound bacterial liquid and water evenly at a mass ratio of 1:0.035:8, and carry out aerobic fermentation at 27°C for 7 days to obtain a fermentation broth;

[0072] Centrifuge the fermentation broth at 1200 rpm for 15 minutes, take the supernatant for filtration, and the obtained filtrate is pandan juice;

[0073] Carry out spray drying on the pandan juice to obtain pandan powder.

[0074] Comparative Example 2

[0075] A method for preparing pandan powder, the steps are as follows:

[0076] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0077] Soak the dried pandan leaves in a Lactobacillus plantarum liquid with an effective viable count of 1×10 7 cfu / mL for 2 minutes to obtain soaked pandan leaves;

[0078] Under a natural environment exposed to sunlight, dry the soaked pandan leaves for 6 hours, then dry them at 38°C for 40 minutes, and crush the pandan leaves after drying to obtain a crushed material (the particle size of the crushed material can be <1 cm);

[0079] (2) Mix tocopherol and tea polyphenols evenly at a mass ratio of 1:2 to obtain an antioxidant, and set aside for later use;

[0080] Mix the Lactococcus lactis liquid and Lactobacillus rhamnosus liquid with an effective viable count of 1×10 7 cfu / mL evenly at a volume ratio of 1:1.5, and set aside for later use;

[0081] (3) Mix the above-mentioned crushed material, antioxidant, compound bacterial liquid and water evenly at a mass ratio of 1:0.02:0.035:8, and carry out aerobic fermentation at 27°C for 7 days to obtain a fermentation broth;

[0082] Centrifuge the fermentation broth at 1200 rpm for 15 minutes, take the supernatant for filtration, and the obtained filtrate is pandan juice;

[0083] Carry out spray drying on the pandan juice to obtain pandan powder.

[0084] Comparative Example 3

[0085] A preparation method of pandan powder, the steps are as follows:

[0086] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0087] Soak the dried pandan leaves in a Lactobacillus plantarum bacterial liquid with an effective viable count of 1×10 7 cfu / mL for 2 min to obtain soaked pandan leaves;

[0088] Under the natural environment exposed to sunlight, dry the soaked pandan leaves for 6 h, then dry them at 38 °C for 40 min. After drying, crush the pandan leaves to obtain a crushed product (the particle size of the crushed product can be <1 cm);

[0089] (2) Mix tocopherol and tea polyphenols evenly according to a mass ratio of 1:0.5 to obtain an antioxidant for standby;

[0090] Mix a Lactobacillus plantarum bacterial liquid and a Lactobacillus rhamnosus bacterial liquid with an effective viable count of 1×10 7 cfu / mL evenly according to a volume ratio of 1:1.5 for standby;

[0091] (3) Mix the above-mentioned crushed product, antioxidant, compound bacterial liquid and water evenly according to a mass ratio of 1:0.02:0.035:8, and carry out aerobic fermentation at 27 °C for 7 d to obtain a fermentation broth;

[0092] Centrifuge the fermentation broth at 1200 rpm for 15 min, take the supernatant for filtration, and the obtained filtrate is pandan juice;

[0093] Carry out spray drying on the pandan juice to obtain pandan powder.

[0094] Comparative Example 4

[0095] A preparation method of pandan powder, the steps are as follows:

[0096] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0097] Crush the dried pandan leaves to obtain a crushed product (the particle size of the crushed product can be <1 cm);

[0098] (2) Mix tocopherol and tea polyphenols evenly according to a mass ratio of 1:0.5 to obtain an antioxidant for standby;

[0099] Mix a Lactococcus lactis bacterial liquid and a Lactobacillus rhamnosus bacterial liquid with an effective viable count of 1×10 7 cfu / mL evenly according to a volume ratio of 1:1.5 for standby;

[0100] (3) Mix the above-mentioned crushed material, antioxidant, compound bacterial liquid and water evenly according to a mass ratio of 1:0.02:0.035:8, and carry out aerobic fermentation at 27 °C for 7 days to obtain a fermentation broth;

[0101] Centrifuge the fermentation broth at 1200 rpm for 15 minutes, take the supernatant for filtration, and the obtained filtrate is pandan juice;

[0102] Carry out spray drying on the pandan juice to obtain pandan powder.

[0103] Comparative Example 5

[0104] A method for preparing pandan powder, the steps are as follows:

[0105] (1) Select healthy and mature pandan leaves, wash them clean and dry them to obtain dried pandan leaves;

[0106] Soak the dried pandan leaves in a Lactobacillus plantarum bacterial liquid with an effective viable count of 1×10 7 cfu / mL for 2 minutes to obtain soaked pandan leaves;

[0107] Under the natural environment exposed to sunlight, dry the soaked pandan leaves for 6 hours, then dry them at 38 °C for 40 minutes, and crush the pandan leaves after drying to obtain a crushed material (the particle size of the crushed material can be <1 cm);

[0108] (2) Mix tocopherol and tea polyphenols evenly according to a mass ratio of 1:0.5 to obtain an antioxidant for standby;

[0109] Mix the Lactococcus lactis bacterial liquid and the Lactobacillus rhamnosus bacterial liquid with an effective viable count of 1×10 7 cfu / mL evenly according to a volume ratio of 1:1.5 for standby;

[0110] (3) Mix the above-mentioned crushed material, antioxidant, compound bacterial liquid and water evenly according to a mass ratio of 1:0.05:0.08:8, and carry out aerobic fermentation at 27 °C for 7 days to obtain a fermentation broth;

[0111] Centrifuge the fermentation broth at 1200 rpm for 15 minutes, take the supernatant for filtration, and the obtained filtrate is pandan juice;

[0112] Carry out spray drying on the pandan juice to obtain pandan powder.

[0113] Application Example 1

[0114] Detect the fragrance and solubility of the pandan powder prepared in Examples 1-3 and Comparative Examples 1-5, and the results are shown in Table 1;

[0115] Among them, the fragrance of the pandan powder is directly smelled through the nose;

[0116] Solubility of pandan powder: Take 100 g of pandan powder samples from each treatment and place them in 1000 mL of warm water at 50 °C, stir evenly; after standing for half an hour, observe whether there is precipitation. If there is no precipitation, it indicates good solubility.

[0117] Table 1 Aroma and solubility of pandan powder in different treatments

[0118] Treatment Aroma Solubility Example 1 Rich No precipitation Example 2 Rich No precipitation Example 3 Rich No precipitation Comparative Example 1 Light No precipitation Comparative Example 2 Rich Slight precipitation Comparative Example 3 Rich Slight precipitation Comparative Example 4 Light No precipitation Comparative Example 5 Rich No precipitation

[0119] Observe the color of the pandan powder prepared in Examples 1 - 3 and Comparative Examples 1 - 5, and then store the pandan powder in different treatments in the same room temperature environment, and record the colors at 0 d, 10 d, 20 d, and 30 d of storage respectively. The results are shown in Table 2.

[0120] Table 2 Color of pandan powder in different treatments

[0121] Treatment 0d 10d 20d 30d Example 1 Emerald green Emerald green Emerald green Emerald green Example 2 Emerald green Emerald green Emerald green Emerald green Example 3 Emerald green Emerald green Emerald green Emerald green Comparative Example 1 Emerald green Light green Light green Pale green Comparative Example 2 Emerald green Emerald green Light green Light green Comparative Example 3 Emerald green Emerald green Emerald green Light green Comparative Example 4 Emerald green Emerald green Emerald green Light green Comparative Example 5 Emerald green Emerald green Emerald green Emerald green

[0122] Combined with the data in Table 1 and Table 2, it can be seen that after preparing pandan powder using the technical solutions provided in Examples 1 - 3 and Comparative Example 5, it has a strong aroma, good solubility, and strong color stability of bright green. However, the pandan powder prepared in Comparative Examples 1 - 4 has insufficient aroma, poor color stability, or poor solubility, all of which are not conducive to the preparation of pandan powder.

[0123] Application Example 2

[0124] Take 25 healthy mice with a body weight of 19 - 21 g and raise them in the same environment for 2 days; then randomly divide the mice into 5 groups with 5 mice in each group; take the pandan powder prepared in Examples 1 - 3 and Comparative Example 5, and prepare a pandan solution with a mass concentration of 15% to intragastrically administer the mice 2 times a day, 1 mL each time; use the treatment of intragastrically administering the same volume of water as the blank control; 1 h after the last intragastric administration, intraperitoneally inject each group of mice with a dose of 40 mg / kg of sodium pentobarbital to make the mice sleep, and then record the average sleep time of the 5 mice in each group. The results are shown in Table 3.

[0125] Table 3 Average sleep duration of mice in different treatments

[0126] Treatment Sleep duration (min) Example 1 56.2 Example 2 55.5 Example 3 54.3 Comparative Example 5 43.5 Blank control 42.6

[0127] Combined with the data in Table 3, it can be seen that the pandan powder prepared in Examples 1 - 3 has more comprehensive effective active ingredients, which is beneficial to improving the sleep of mice; while for the pandan powder prepared in Comparative Example 5, although its aroma and color are no different from those in the examples due to the adjustment of parameters during the preparation process, it may lead to the lack of certain effective active ingredients, thus being not conducive to the exertion of its sleep - improving effect.

[0128] Application Example 3

[0129] A preparation method of pandan coconut milk pastry, the steps are as follows:

[0130] Treatment 1: By mass, it includes the following raw materials: 18 parts of eggs, 5 parts of flour, 1 part of pandan powder prepared in Example 1, 4 parts of coconut milk, 2.5 parts of oil, 0.2 part of baking powder and 1.5 parts of sugar.

[0131] Steps:

[0132] Separate the egg yolks and egg whites in the eggs for later use;

[0133] Add oil and coconut milk to the egg yolks and stir evenly, then add flour, pandan powder and baking powder and stir evenly again to obtain a mixture;

[0134] Mix and whip the egg whites and sugar to obtain a meringue;

[0135] Mix the mixture and the meringue evenly and then bake to obtain the pandan coconut milk pastry.

[0136] Treatment 2: The difference from the above Treatment 1 is only that the pandan powder prepared in Example 2 is used to replace the pandan powder prepared in Example 1;

[0137] Treatment 3: The difference from the above Treatment 1 is only that the pandan powder prepared in Example 3 is used to replace the pandan powder prepared in Example 1;

[0138] Treatment 4: The difference from the above Treatment 1 is only that the conventionally purchased pandan powder is used to replace the pandan powder prepared in Example 1.

[0139] Compare the smell and appearance color of the pandan coconut milk pastries prepared in the above Treatments 1-4, and the results are shown in Table 4.

[0140] Table 4 Comparison of pandan coconut milk pastries in different treatments

[0141] Treatment Odor Color Treatment 1 Combined with pandan aroma and coconut milk aroma Emerald green Treatment 2 Combined with pandan aroma and coconut milk aroma Emerald green Treatment 3 Combined with pandan aroma and coconut milk aroma Emerald green Treatment 4 Rich coconut milk aroma, but weak pandan odor Color is on the black side

[0142] As can be seen from Table 4, after preparing the pandan coconut milk pastry by using the technical solution provided by the present invention, it has both pandan aroma and coconut milk aroma, and at the same time has a bright green color, increasing the appetite of the drinker; while after preparing the pandan coconut milk pastry by using the solution in Treatment 4, its pandan smell is weak and the appearance color is poor. It can be seen that the pandan powder prepared by the present invention has the advantages of aroma concentration and color stability, and at the same time is beneficial to improving sleep disorders.

[0143] In summary, the preparation method of the pandan powder provided by the present invention is not only beneficial to decomposing the organic substances in pandan leaves, releasing more aroma components, and stabilizing the pigment components, making the color of the pandan powder more vivid and lasting; at the same time, it can also effectively release the bioactive components in the pandan powder and assist in enhancing the aroma and flavor of the pandan powder. Therefore, the pandan coconut milk pastry prepared by the present invention not only has good flavor and appearance, but also is rich in nutritional value.

[0144] Although the above embodiments have described the present invention in detail, they are only a part of the embodiments of the present invention, rather than all embodiments. People can also obtain other embodiments based on this embodiment without creative efforts, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preparing colorful powder, characterized in that: The steps include: Soaking the pandan leaves in a Lactobacillus plantarum bacterial solution to obtain pretreated pandan leaves; The pretreated pandan leaves are sequentially aired, dried and crushed to obtain a crushed product; The crushed material, antioxidant, composite bacterial liquid and water are mixed and aerobically fermented to obtain a fermentation liquid; The fermentation liquid is centrifuged and filtered in sequence to obtain a pandan juice; The pandan juice is spray-dried to obtain pandan powder; The composite bacterial liquid is composed of a Lactococcus lactis bacterial liquid and a Lactobacillus rhamnosus bacterial liquid; The antioxidant is composed of tocopherol and tea polyphenols in a mass ratio of 1:0.5-0.

7.

2. The preparation method according to claim 1, characterized in that: When the pandan leaves are soaked with Lactobacillus plantarum liquid, the effective viable bacteria count of the Lactobacillus plantarum liquid is ≥ 1×10 7 cfu / mL; The soaking time is 1-2 minutes.

3. The preparation method according to claim 1, characterized in that: The volume ratio of the Lactococcus lactis bacterial solution to the Lactobacillus rhamnosus bacterial solution in the composite bacterial solution is 1:1.5-2; The effective viable counts of the Lactococcus lactis bacterial solution and the Lactobacillus rhamnosus bacterial solution were 1×10 7 -2×10 7 cfu / mL.

4. The preparation method according to claim 1, characterized in that: The drying comprises: drying the pandan leaves sprayed with Lactobacillus plantarum liquid for 6-8 hours in a natural environment exposed to sunlight; The drying process includes: a temperature of 35-40° C. and a time of 40-50 minutes.

5. The preparation method according to claim 1, characterized in that: The mass ratio of the crushed material, antioxidant, composite bacterial liquid and water is 1: 0.02-0.03: 0.035-0.05: 5-8; The temperature of the aerobic fermentation is 27-30°C and the time is 5-7 days.

6. The preparation method according to claim 1, characterized in that: The centrifugal speed is 1000-1500 rpm; the centrifugal time is 15-20 min.

7. The iridescent powder obtained by the preparation method according to any one of claims 1 to 6.

8. Application of the iridescent powder according to claim 7 in food.

9. A colorful coconut milk cake, characterized in that: The invention comprises the following raw materials by weight: 18-20 parts of eggs, 4.5-5 parts of flour, 1-1.5 parts of the colorful powder according to claim 7, 3.5-4 parts of coconut milk, 2.5-3 parts of oil, 0.2-0.3 parts of baking powder and 1.5-2 parts of sugar.

10. The method for preparing the colorful coconut milk cake according to claim 9, characterized in that: The steps include: Separate the egg yolk and egg white; Add oil, coconut milk, flour, pandan powder and baking powder to the egg yolk in sequence and mix well to obtain a mixture; Mix the egg white and sugar and beat to obtain meringue; The mixture is mixed with meringue and then baked to obtain a colorful coconut milk cake.