Preparation method of bamboo leaf eggs with rich fragrance and rich nutrition

Abstract

The invention discloses a preparation method of bamboo leaf eggs with rich fragrance and rich nutrition, and belongs to the field of food processing. The preparation method comprises the following steps: washing eggs, putting the eggs into a pot, adding water, and boiling the eggs with fire; after the eggs are boiled, cooking with soft fire, stopping heating, and continuously braising; pouring out the cooked eggs, flushing the eggs with cold water, and breaking the eggs into pieces; frying the seasoning containing the bamboo leaves with big fire; adding water and seasonings, boiling with big fire, adjusting medium fire, adding the broken eggs, and boiling with small fire for 30-60 minutes; and after stopping heating, soaking the eggs until the eggs are tasty. The bamboo leaf eggs prepared by the method have double taste feelings, and have the faint scent of the bamboo leaves and the mellow fragrance of the eggs; the bamboo leaf eggs contain proteins with relatively small molecular weight, so that further hydrolysis and absorption of the body are facilitated, and the eggs participate in various processes in the body; the bamboo leaf eggs contain nutritional ingredients of eggs, flavones, polyphenols and the like are additionally added, and meanwhile the bamboo leaf eggs have the effects of resisting oxidation, reducing blood sugar and reducing lipid.

Description

Technical Field

[0001] The invention relates to a method for processing eggs, bamboo leaves, other spices and other food materials into mature eggs, belonging to the field of food processing. Background Art

[0002] Eggs, especially eggs, which are the most commonly consumed by Chinese people, play an important role in our daily diet. The biological value of egg protein is 94, which is higher than that of milk (85), beef (76) and pork (74). Eggs are rich in protein, minerals and other nutrients. The egg white contains 11% protein; the egg yolk contains 31% fat and 17% protein.

[0003] my country has a rich variety of egg products, including preserved eggs (pine eggs), salted duck eggs, fragrant stewed eggs, tea eggs, smoked eggs and stewed eggs, providing consumers with a variety of choices. Tea eggs are one of China's famous snacks. They are boiled eggs with tea added during the cooking process. Some places will add stewing ingredients. Because they are simple to make and easy to carry, they are often sold in small pots at stations, streets and alleys, and places with many tourists and pedestrians. They are good quality and cheap.

[0004] The molecular weight of protein is one of the important indicators for evaluating the properties and functions of protein, and it affects the digestion and absorption of protein. Proteins or peptides with smaller molecular weights are easier to be absorbed by the human body. The molecular weight of protein in eggs may vary due to different cooking processes. Boiled eggs are a relatively mild cooking method. The temperature is low and the cooking time is short, which causes less damage to the protein structure and the molecular weight of the protein does not change much. Therefore, the digestion and absorption rate of protein is high. Tea and other seasonings are added to tea eggs during the production process. After long-term cooking, the protein in tea eggs may cause coagulation or denaturation of protein molecules due to the interaction with the components in tea during the long heating process, which is not conducive to the digestion and absorption of protein. In addition, tannins in tea (such as tannic acid) react with proteins in food to produce coagulated substances that are deposited in the body, seriously affecting the body's absorption of protein. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a method for making bamboo leaf eggs, which uses bamboo leaves as the main ingredient to replace the tea leaves in tea eggs, and is combined with other spices and food materials to achieve a unique flavor while avoiding the disadvantage of tea eggs that are not conducive to nutrient absorption, and further improve the nutrition of cooked eggs.

[0006] The first purpose of the present invention is to provide a method for making bamboo leaf eggs. Bamboo leaves are added into the eggs during cooking and cooked together. The bamboo leaves are dry bamboo leaves or fresh bamboo leaves.

[0007] In one embodiment, the amount of bamboo leaves added is 1.7-4.0 g / L for dry bamboo leaves or 5.0-12.5 g / L for fresh bamboo leaves, calculated based on the amount of water added.

[0008] In one embodiment, the preparation method comprises:

[0009] (1) Wash the eggs, put them in a pot, add water and boil them over medium heat;

[0010] (2) After the eggs are boiled, turn down the heat and continue to cook, then stop heating and simmer until the eggs are cooked through;

[0011] (3) Pour out the cooked eggs, rinse with cold water and crack them;

[0012] (4) stir-frying the seasoning containing bamboo leaves over high heat;

[0013] (5) Add water and seasonings, bring to a boil over high heat, then reduce heat to medium, add cracked eggs and simmer for 30-60 minutes;

[0014] (6) After stopping heating, soak the eggs until they are well-seasoned.

[0015] In one embodiment, the eggs are one or more of common eggs, free-range eggs, and eggs laid by bamboo forest chickens; preferably eggs laid by bamboo forest chickens.

[0016] In one embodiment, the bamboo leaves are the perennial herbaceous plant Bambusa longituba of the genus Bambusa of the Poaceae family; the fresh bamboo leaves are directly picked and then washed; and the dried bamboo leaves are obtained by drying the picked and washed fresh bamboo leaves.

[0017] In one embodiment, the seasoning in step (4) is specifically composed of: 5-8 parts of dried bamboo leaves or 15-25 parts of fresh bamboo leaves, 4-6 parts of star anise, 8-10 parts of cinnamon, 0.03-0.04 parts of pepper, 20-40 parts of ginger, 200-250 parts of dark soy sauce, 10-15 parts of cumin powder, 0.08-0.12 parts of cloves, and 20-25 parts of xylitol.

[0018] In one embodiment, step (2) is specifically as follows: after the eggs are boiled, the heat is reduced and the eggs are continued to cook for 2-3 minutes, and then the heating is stopped and the eggs are simmered for 2-3 minutes until the eggs are cooked.

[0019] In one embodiment, step (3) specifically comprises pouring out the cooked eggs, rinsing them with cold water for 3 to 10 minutes, and then cracking them while they are still hot; preferably, rinsing them with cold water for 5 minutes and then cracking them while they are still hot.

[0020] In one embodiment, the stir-frying in step (4) is stir-frying on high heat for 1 to 5 minutes, preferably stir-frying on high heat for 2 to 3 minutes. In the present invention, stir-frying the seasoning on high heat is to better stimulate the aroma of the seasoning.

[0021] In one embodiment, in step (5), while the eggs are being cooked over low heat, the eggs are flipped after being cooked for 15 to 30 minutes, and then continued to be cooked over low heat for 15 to 30 minutes after flipping; preferably, the eggs are continued to be cooked over low heat for 15 to 20 minutes after being flipped.

[0022] In one embodiment, in step (5), the amount of water added is 1 to 2 L for every 10 eggs.

[0023] In one embodiment, according to the amount of water added in step (5), the amount of bamboo leaves in the seasoning is 1.7-4.0 g / L of dry bamboo leaves or 5.0-12.5 g / L of fresh bamboo leaves; other seasonings are adjusted according to the amount of bamboo leaves.

[0024] In one embodiment, step (6) specifically includes soaking for 5 to 25 hours after stopping heating until the eggs are flavored; preferably soaking for 10 to 20 hours.

[0025] In one embodiment, the preparation method specifically comprises the following steps:

[0026] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0027] (2) When the water boils, immediately turn the heat to low and continue cooking for 2 to 3 minutes. Then stop heating and simmer for 2 to 3 minutes until the eggs are cooked through.

[0028] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 1 to 5 minutes, and then crack the eggs while they are still hot;

[0029] (4) After adding 20-60 mL of water to the pot again, add the following ingredients except the eggs: 5-8 g of dried bamboo leaves or 15-25 g of fresh bamboo leaves, 4-6 g of star anise, 8-10 g of cinnamon, 0.03-0.04 g of pepper, 20-40 g of ginger, 200-250 g of dark soy sauce, 10-15 g of cumin powder, 0.08-0.12 g of cloves, and 20-25 g of xylitol, and stir-fry over high heat for 2-5 min;

[0030] (5) Add 2 to 3 L of water to the ingredients in step (4), bring to a boil over high heat, then reduce to medium heat, add the cracked eggs in step (3), and simmer over low heat for 15 to 30 minutes;

[0031] (6) Turn the eggs over, moving the eggs at the bottom of the pot to the top so that they are more evenly seasoned. Continue to simmer for 15 to 30 minutes.

[0032] (7) Turn off the heat and stop heating. Soak the eggs in the pot for 10 to 20 hours.

[0033] The second object of the present invention is to provide a bamboo leaf egg produced by the above-mentioned production method, wherein the bamboo leaf egg has the fresh fragrance of bamboo leaves, the mellow fragrance of eggs, and the rich taste experience provided by other food materials; the bamboo leaf egg has the nutrition of protein, amino acids and lecithin contained in the egg itself, and additionally has the nutrients such as flavonoids and polyphenols of plant ingredients, and has the effects of anti-oxidation, lowering blood sugar and lowering blood lipids.

[0034] The third object of the present invention is to provide a seasoning packet for making bamboo leaf eggs, which comprises: 5-8 parts of dry bamboo leaves or 15-25 parts of fresh bamboo leaves, 4-6 parts of star anise, 8-10 parts of cinnamon, 0.03-0.04 parts of pepper, 20-40 parts of ginger, 200-300 parts of dark soy sauce, 10-15 parts of cumin powder, 0.08-0.12 parts of cloves, and 20-25 parts of xylitol.

[0035] Beneficial Effects

[0036] (1) The bamboo leaf eggs prepared by the present invention have the fragrance of bamboo leaves, the mellow fragrance of eggs, and the rich taste experience provided by other food materials;

[0037] (2) The bamboo leaf eggs produced by the present invention can obtain proteins with smaller molecular weights. After people or animals eat the eggs, it will be beneficial for further hydrolysis of the proteins, which will have a better absorption effect on the proteins and will effectively participate in various biochemical reactions and metabolic processes in the body.

[0038] (3) The bamboo leaf eggs prepared by the present invention not only have the nutrients of protein, amino acids and lecithin contained in the eggs themselves, but also have additional nutrients such as flavonoids and polyphenols from plant ingredients, and also have the effects of anti-oxidation, lowering blood sugar and lowering blood lipids. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Comparison of the contents of important volatile components.

[0040] Figure 2 This is a subjective rating result. DETAILED DESCRIPTION

[0041] The eggs involved in the following embodiments are commercially available eggs; the bamboo leaves refer to the leaves of the perennial herbaceous plant Lophatherum gracile Brongn. of the genus Lophatherum of the Poaceae family. The fresh bamboo leaves are washed bamboo leaves, and the dried bamboo leaves are sun-dried products.

[0042] In a specific embodiment of the present invention, for ease of operation, spices such as star anise, pepper, ginger, cloves, etc. are added by weight using a quantity meter.

[0043] Example 1

[0044] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0045] (2) When the water boils, immediately turn the heat down to low and continue cooking for 2 minutes. Then stop heating and simmer for 3 minutes until the eggs are cooked through.

[0046] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0047] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 20 g of fresh bamboo leaves, 2 star anise, 8 g of cinnamon, 20 peppercorns, 5 slices of ginger, 250 mL of dark soy sauce, 10 g of cumin powder, 4 cloves, and 25 g of xylitol, and stir-fry over high heat for 2 min;

[0048] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 20 minutes;

[0049] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 20 minutes.

[0050] (7) After 20 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 20 hours.

[0051] Example 2

[0052] (1) Wash 15 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0053] (2) When the water boils, immediately turn the heat to low and continue cooking for 2 minutes. Then stop heating and simmer for 2 minutes until the eggs are cooked through.

[0054] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0055] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 5 g of dried bamboo leaves, 2 star anise, 8 g of cinnamon, 20 peppercorns, 5 slices of ginger, 200 mL of dark soy sauce, 10 g of cumin powder, 4 cloves, and 20 g of xylitol, and stir-fry over high heat for 2 min;

[0056] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 15 minutes;

[0057] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 15 minutes.

[0058] (7) After 15 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 10 hours.

[0059] Example 3

[0060] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0061] (2) When the water boils, immediately turn the heat down to low and continue cooking for 2 minutes. Then stop heating and simmer for 3 minutes until the eggs are cooked through.

[0062] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0063] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 8 g of dried bamboo leaves, 3 star anises, 10 g of cinnamon, 25 peppercorns, 8 slices of ginger, 250 mL of dark soy sauce, 15 g of cumin powder, 6 cloves, and 25 g of xylitol, and stir-fry over high heat for 3 min;

[0064] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 20 minutes;

[0065] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 20 minutes.

[0066] (7) After 20 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 20 hours.

[0067] Comparative Example 1

[0068] The specific implementation method is the same as that of Example 1, except that bamboo leaves are not used in the food material for boiling eggs.

[0069] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0070] (2) When the water boils, immediately turn the heat down to low and continue cooking for 2 minutes. Then stop heating and simmer for 3 minutes until the eggs are cooked through.

[0071] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0072] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 2 star anise, 8 g of cinnamon, 20 peppercorns, 5 slices of ginger, 250 mL of dark soy sauce, 10 g of cumin powder, 4 cloves, and 25 g of xylitol, and stir-fry over high heat for 2 min;

[0073] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 20 minutes;

[0074] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 20 minutes.

[0075] (7) After 20 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 20 hours.

[0076] Comparative Example 2

[0077] The specific implementation method is the same as Example 1, except that 5g of black tea leaves are used instead of 20g of fresh bamboo leaves in the food material for boiling eggs.

[0078] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0079] (2) When the water boils, immediately turn the heat down to low and continue cooking for 2 minutes. Then stop heating and simmer for 3 minutes until the eggs are cooked through.

[0080] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0081] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 5 g of black tea leaves, 2 star anise, 8 g of cinnamon, 20 peppercorns, 5 slices of ginger, 250 mL of dark soy sauce, 10 g of cumin powder, 4 cloves, and 25 g of xylitol, and stir-fry over high heat for 2 min;

[0082] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 20 minutes;

[0083] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 20 minutes.

[0084] (7) After 20 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 20 hours.

[0085] Comparative Example 3

[0086] The specific implementation method is the same as that of Example 1, except that the amount of fresh bamboo leaves used in the food material for boiling eggs is 30g

[0087] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0088] (2) When the water boils, immediately turn the heat down to low and continue cooking for 2 minutes. Then stop heating and simmer for 3 minutes until the eggs are cooked through.

[0089] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0090] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 30 g of fresh bamboo leaves, 2 star anise, 8 g of cinnamon, 20 peppercorns, 5 slices of ginger, 250 mL of dark soy sauce, 10 g of cumin powder, 4 cloves, and 25 g of xylitol, and stir-fry over high heat for 2 min;

[0091] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 20 minutes;

[0092] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 20 minutes.

[0093] (7) After 20 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 20 hours.

[0094] Comparative Example 4

[0095] The specific implementation method is the same as that of Example 2, except that the amount of dried bamboo leaves in the food material for boiling eggs is 3g

[0096] (1) Wash 15 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0097] (2) When the water boils, immediately turn the heat to low and continue cooking for 2 minutes. Then stop heating and simmer for 2 minutes until the eggs are cooked through.

[0098] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0099] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 3 g of dried bamboo leaves, 2 star anise, 8 g of cinnamon, 20 peppercorns, 5 slices of ginger, 200 mL of dark soy sauce, 10 g of cumin powder, 4 cloves, and 20 g of xylitol, and stir-fry over high heat for 2 min;

[0100] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 15 minutes;

[0101] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 15 minutes.

[0102] (7) After 15 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 10 hours.

[0103] Comparative Example 5

[0104] The specific implementation method is the same as that of Example 3, except that the amount of dried bamboo leaves in the food material for boiling eggs is 10g

[0105] (1) Wash 20 eggs, put them in a pot, add water to cover the eggs, and cook them over medium heat;

[0106] (2) When the water boils, immediately turn the heat down to low and continue cooking for 2 minutes. Then stop heating and simmer for 3 minutes until the eggs are cooked through.

[0107] (3) Pour out the hot water in the pot, pour out the eggs, rinse them with cold water for 5 minutes, and then crack the eggs while they are still hot;

[0108] (4) After adding 50 mL of water to the pot again, add the following ingredients except the egg: 10 g of dried bamboo leaves, 3 star anise, 10 g of cinnamon, 25 peppercorns, 8 slices of ginger, 250 mL of dark soy sauce, 15 g of cumin powder, 6 cloves, and 25 g of xylitol, and stir-fry over high heat for 3 min;

[0109] (5) Add 2.5 L of water to the ingredients in step (4), bring to a boil over high heat, then turn to medium heat, add the cracked eggs in step (3), and simmer over low heat for 20 minutes;

[0110] (6) Turn the eggs over, and flip the eggs at the bottom of the pot to the top to make them more evenly flavored. Continue to cook on low heat for 20 minutes.

[0111] (7) After 20 minutes, turn off the heat and stop heating. Let the eggs soak in the pot for 20 hours.

[0112] Example 4: Protein detection method

[0113] Sample preparation: After peeling the cooked eggs, add appropriate amount of ultrapure water and stir the whole eggs evenly with a homogenizer to make a whole egg mixture. 100 μL of the whole egg mixture sample was fully mixed with an equal volume of lysis buffer (0.3% SDS, 3% DTT, protease inhibitors and 0.5 mol / L Tris / HCl, pH 8.0) and then subjected to ultrasonic pulverization at low temperature. After reacting at room temperature for 1 hour, centrifuge at 4°C and 12000 rpm for 20 minutes to remove the precipitate. Take the supernatant, use 1 mg / mL bovine serum albumin solution as the standard solution, determine the protein concentration by Bradford method, and then divide into 120 μg samples per tube and store in a -80°C refrigerator.

[0114] SDS-PAGE: Use 8% separation gel (1.5mol / L Tris (pH8.8): 40% Acry / Bris = 29:1, distilled water, 10% SDS, 10% APS, TEMED), and use the same protein content loading method, and separate at 100V. After the electrophoresis, take out the gel, rinse with ultrapure water, and fix it in a fixative (30% (volume ratio) methanol, 10% (volume ratio) acetic acid). After fixing for 1 hour, take out the gel and stain it in Coomassie Brilliant Blue staining solution for 24 hours. After staining, decolorize with a destaining solution (1% acetic acid) and then collect images.

[0115] The results showed that among the six samples, the bands with denser and darker colors were around 60-70 kDa and 85 kDa, indicating that the molecular weight of egg protein in the bamboo leaf eggs cooked by the scheme of the present invention (Example 1, Example 2, Example 3) and the comparative example was concentrated in these two areas.

[0116] However, Examples 1, 2, and 3 have obvious bands in the lower molecular weight region of 25 to 30 kDa, and the color and width of the bands are very impressive, indicating that when bamboo leaves and other spices are added to cook eggs, the egg protein contains low molecular weight proteins (25 to 30 kDa); boiled eggs with 30 g of fresh bamboo leaves (Comparative Example 3) and 10 g of dry bamboo leaves (Comparative Example 5) also have 25 to 30 kDa proteins.

[0117] In comparative example 1, the other ingredients and cooking methods are the same as those in example 1, except that the bamboo leaves are removed; in comparative example 2, the bamboo leaves are replaced with black tea leaves commonly used for cooking tea eggs; and in comparative example 4, the amount of bamboo leaves used is relatively small, which is lower than that of the invention solution. In the cooked eggs prepared by these three methods, there is no small molecular weight protein, and the protein is more likely to condense into large molecular weight protein.

[0118] When the molecular weight of egg protein is lower, it will be beneficial for further hydrolysis of protein after consumption by humans or animals, and the absorption effect of protein will be better. It can be seen that the appropriate addition of bamboo leaves can contain more small molecular weight proteins in eggs, which is more conducive to subsequent protein digestion and absorption. The bamboo leaf eggs prepared by the bamboo leaf egg preparation method provided by the present invention (5-8g of dry bamboo leaves or 15-25g of fresh bamboo leaves are added to the seasoning) can obtain lower molecular weight proteins and related active functions.

[0119] Example 5: Aroma Detection Method

[0120] Sample aroma extraction: Place a shelled hard-boiled egg in a beaker sealed with a sealing film, insert an SPME fiber head and adsorb for 50 minutes at room temperature; desorb the extraction head at 250°C for 3 minutes, and then perform GC-MS separation and identification.

[0121] Determination method:

[0122] GC-MS chromatographic conditions: injection port temperature 250°C, capillary column temperature 50°C.

[0123] Elution procedure: starting temperature 50°C, hold for 2 min; increase to 120°C at 5°C / min, hold for 15 min; increase to 180°C at 5°C / min, hold for 2 min; increase to 80°C at 30°C / min, hold for 2 min.

[0124] Mass spectrometry conditions: ion source EI; acquisition mode full scan; solvent delay 6min; EMV mode relative value; mass scan range 25.00~550.00amu; MS ion source temperature 230℃, MS quadrupole temperature 150℃. After diluting the normal alkane mixed standard C8~C40 n-hexane 100 times, liquid injection was performed and the analysis was performed according to the above chromatographic conditions.

[0125] Aroma is an important evaluation index for cooked egg products. Tea eggs have the fragrance of tea and the flavor of other spices, which makes people eat more appetizing. The GC-MS method is used to analyze the smell of cooked eggs, which can more accurately understand the impact of cooking methods and ingredient formulas on the finished product. The analysis results are shown in Table 1 below.

[0126] Table 1 Comparison of aroma components of eggs cooked by different methods

[0127]

[0128] As can be seen from the above table, the GC-MS method using headspace extraction can analyze hydrocarbons, alcohols, esters, terpenes, aldehydes, aromatic compounds and nitrogen-containing compounds; among them, hydrocarbon compounds have the highest content (34.46-43.77%), but most aliphatic hydrocarbon compounds have no special smell and contribute little to the aroma components of cooked eggs; most esters, aldehydes and aromatic compounds have low aroma thresholds and contribute greatly to the aroma components, such as decanal with orange, fat and melon aromas, phenylacetaldehyde with rose and chocolate aromas, nonanal with fat and flower aromas, 2,4-di-tert-butylphenol, ethyl phthalate, etc.; in addition, most terpene compounds are active, such as pinene, limonene, myrcene, cedrene, etc.

[0129] according to Figure 1It can be seen that the esters, aldehydes, aromatic compounds and terpenes contained in Examples 1, 2 and 3 are significantly higher than those in Comparative Examples 1 to 5. Comparative Example 1 does not add bamboo leaves, Comparative Example 2 uses 5g of black tea leaves to replace bamboo leaves, and Comparative Example 4 uses less dry bamboo leaves (3g) than the inventive solution. Therefore, the aroma components of the cooked eggs in these three comparative examples are less in esters, aldehydes, aromatic compounds and terpenes than those in the examples; however, Comparative Examples 3 and 5 use more bamboo leaves than the inventive solution (30g of fresh bamboo leaves and 10g of dry bamboo leaves, respectively), but do not achieve more important compound content than the examples.

[0130] It can be seen that the addition of bamboo leaves and the addition of an appropriate amount is one of the necessary factors for obtaining more flavor substances and active ingredients. Only the bamboo leaf egg production method provided by the scheme of the present invention (adding 5 to 8 g of dry bamboo leaves or 15 to 25 g of fresh bamboo leaves to the ingredients) can obtain cooked eggs with richer flavor and stronger related active functions.

[0131] Example 6: Sensory Evaluation

[0132] The sensory evaluation team selected sensory assessors according to the provisions of GB / T 16291.1-2012, and submitted three coded cooked egg samples to each assessor, two of which were exactly the same. The assessors observed and tasted each sample from left to right in order, and selected a different sample from them to determine whether the assessors could assess the sensory differences between the different samples. After screening, a sensory evaluation team was formed by 10 assessors (5 men and 5 women).

[0133] Before conducting the test, each team member must conduct a sensory evaluation of the reference materials used in order to better understand the various sensory indicators. Using the method of quantitative descriptive sensory analysis, the evaluation team evaluated the appearance, aroma, taste, mouthfeel, and overall acceptance of the cooked eggs according to their respective preferences. The full score is 10 points. The detailed scoring criteria are listed in Table 2 below. All sensory tests are conducted in the sensory evaluation room. In order to prevent the influence of sequence effects, the samples are randomly marked with three people and randomly delivered to each sensory evaluator. Each sample is evaluated three times, and the average value is used as the final score.

[0134] Table 2 Sensory scoring standards

[0135]

[0136]

[0137] The scoring results are shown in Table 3. Figure 2 .

[0138] Table 3 Subjective scoring results

[0139]

[0140] From the subjective evaluation results of the tasters, we can see that:

[0141] The amount of bamboo leaves added has little effect on the appearance of the cooked eggs, because the main color is provided by the soy sauce among the other ingredients. The bamboo leaves or tea leaves have a slight effect on the depth of color, but the overall color and texture of the egg surface are similar.

[0142] From the perspective of taste and overall acceptability, the overall scores of Examples 1, 2, and 3 are better than those of the other comparative examples.

[0143] According to the description of the tasters, the bamboo leaf eggs of Examples 1, 2, and 3 are fragrant, with a light plant fragrance; they are salty and delicious; they have a rich taste, the egg white part is relatively firm, and the yolk maintains a certain degree of moisture, and the two are combined together to have a distinct taste layer; even the yolk part can taste the plant fragrance, which combined with the fragrance of the spices makes the taste of the bamboo leaf eggs more complex and rich, and the aftertaste is long. After eating, a light fragrance will be left in the mouth, which makes people have endless aftertaste.

[0144] The fragrance of Comparative Examples 1 and 4 is obviously slightly lighter, and the mouthfeel firmness of the egg white is slightly worse. Comparative Example 2 is the taste of ordinary tea eggs, the fragrance of the smell is not as good as the bamboo leaf eggs in the embodiment, and the complexity and richness of the taste are also slightly lower. Comparative Examples 3 and Comparative Examples 5 have an uncomfortable taste and bitterness.

[0145] It can be seen that the addition of bamboo leaves and the addition of an appropriate amount is one of the necessary factors for obtaining cooked eggs with a unique flavor. Only the bamboo leaf egg production method provided by the scheme of the present invention (adding 5 to 8 g of dry bamboo leaves or 15 to 25 g of fresh bamboo leaves to the ingredients) can obtain cooked eggs with a richer flavor and a better taste.

[0146] Example 7: Detection of flavonoids and polyphenols in eggs cooked by different methods

[0147] (1) The flavonoid content in boiled eggs by different methods was determined by the aluminum nitrate-sodium nitrite method: rutin was used as the reference substance, and the absorbance value was detected by ultraviolet spectrophotometry. Accurately weigh rutin, dissolve it in methanol, and prepare a 10 mg / mL reference substance solution. Accurately pipette 0.5-10 mL of the reference substance solution into a 50 mL volumetric flask, add 1.0 mL of 5% sodium nitrite solution, mix well, let it stand for 6 minutes, add 1.0 mL of 10% aluminum nitrate solution, mix well, let it stand for 6 minutes, then add 10.0 mL of 4% sodium hydroxide solution, mix well, add water to make up the volume, and obtain a test solution with a rutin content of 0.1-2.0 mg / mL. Using the negative control as the blank, measure the absorbance at a wavelength of 510 nm, and the linear relationship between the absorbance value (A) and the concentration (C) is A=0.53C-0.0216(R 2=0.995).

[0148] Sample preparation method: Take the egg white of 5 cooked eggs, absorb the surface moisture with absorbent paper, weigh and record, add 200mL 70% ethanol solution, crush with a food processor, and then heat and reflux in a water bath for extraction, the extraction temperature is 80℃, and the extraction time is 2h. After the crude extract is cooled to room temperature, it is filtered under reduced pressure to remove the residue. The filtrate is concentrated by rotary evaporation at 50℃ to remove the ethanol in the filtrate. Use a separatory funnel to extract three times, each time with 50mL chloroform, collect the lower aqueous solution, place it in a 250mL volumetric flask and dilute to the scale with pure water. Accurately pipette 10mL of sample solution into a 50mL volumetric flask, add 1.0mL of 5% sodium nitrite solution, mix well, let stand for 6 minutes, add 1.0mL of 10% aluminum nitrate solution, mix well and let stand for 6 minutes, then add 10.0mL of 4% sodium hydroxide solution, mix well, add water to make up the volume, measure the absorbance value at a wavelength of 510nm, and use the linear curve equation to calculate the concentration of flavonoids in the sample solution. The results are shown in Table 4:

[0149] Table 4 Flavonoid content in eggs cooked by different methods

[0150]

[0151] (2) The polyphenol content in eggs cooked by different methods was determined by the Folin-sodium carbonate method: gallic acid was used as the reference substance, and the absorbance value was detected by ultraviolet spectrophotometry. Accurately weigh gallic acid, dissolve it in pure water, prepare a 1 mg / mL reference substance solution, and gradiently dilute it into a series of solutions ranging from 10 to 50 μg / mL. Pipette 1 mL separately and add it to a 25 mL volumetric flask, add 1 mL of 0.1 mol / L Folin solution and 4 mL of 7.5% sodium carbonate solution, mix well, and make up to volume with pure water. Place it in the dark to react for 1 hour to develop color, and measure the absorbance value at a wavelength of 765 nm. The linear relationship between the absorbance value (A) and the concentration (C) is A=0.0087C+0.0325(R 2 =0.999).

[0152] Sample preparation method: Take the egg whites of 5 cooked eggs, absorb the surface moisture with absorbent paper, weigh and record, add 200mL 60% ethanol solution, break it with a food processor, and extract it with a 500W ultrasonic extractor for 30 minutes, filter the liquid under reduced pressure to remove the residue, centrifuge the filtrate at 4000rpm for 10 minutes, immediately take 1mL of the supernatant and add it to a 25mL volumetric flask, add 1mL 0.1mol / L Folin phenol solution and 4mL 7.5% sodium carbonate solution, mix well, make up to volume with pure water, place it in the dark to react for 1 hour to develop color, measure the absorbance value at a wavelength of 765nm, and calculate the concentration of polyphenols in the sample solution using a linear curve equation. The results are shown in Table 5:

[0153] Table 5 Polyphenol content in eggs cooked by different methods

[0154]

[0155] It can be found that the contents of flavonoids and polyphenols in Examples 1, 2, and 3 are higher than those in Comparative Examples 1 to 5. Comparative Example 1 does not add bamboo leaves, Comparative Example 2 uses 5g of black tea leaves to replace bamboo leaves, and Comparative Example 4 uses less dry bamboo leaves (3g) than the inventive solution, so the contents of flavonoids and polyphenols in the cooked eggs of these three comparative examples are less than those in the examples; however, Comparative Examples 3 and 5 use more bamboo leaves than the inventive solution (30g of fresh bamboo leaves and 10g of dry bamboo leaves, respectively), but do not achieve more flavonoid content than the examples.

[0156] It can be seen that the addition of bamboo leaves and the addition of an appropriate amount is one of the necessary factors for obtaining cooked eggs with a unique flavor. Only the bamboo leaf egg production method provided by the scheme of the present invention (adding 5 to 8 g of dry bamboo leaves or 15 to 25 g of fresh bamboo leaves to the ingredients) can obtain cooked eggs with higher flavonoid and polyphenol content.

[0157] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for making bamboo leaf eggs, characterized in that: Bamboo leaves are added into the eggs during cooking, and the eggs are cooked together. The bamboo leaves are dry bamboo leaves or fresh bamboo leaves.

2. The method according to claim 1, characterized in that: Calculated by the amount of water added, the amount of bamboo leaves added is 1.7-4.0 g / L of dry bamboo leaves or 5.0-12.5 g / L of fresh bamboo leaves.

3. The method according to claim 1, characterized in that: The production method comprises: (1) Wash the eggs, put them in a pot, add water and boil them over medium heat; (2) After the eggs are boiled, turn down the heat and continue to cook, then stop heating and simmer until the eggs are cooked through; (3) Pour out the cooked eggs, rinse with cold water and crack them; (4) stir-frying the seasoning containing bamboo leaves over high heat; (5) Add water and seasonings, bring to a boil over high heat, then reduce heat to medium, add cracked eggs and simmer for 30-60 minutes; (6) After stopping heating, soak the eggs until they are well-seasoned.

4. The method according to claim 3, characterized in that: The seasoning in step (4) is specifically composed of the following: 5-8 parts of dried bamboo leaves or 15-25 parts of fresh bamboo leaves, 4-6 parts of star anise, 8-10 parts of cinnamon, 0.03-0.04 parts of pepper, 20-40 parts of ginger, 200-250 parts of dark soy sauce, 10-15 parts of cumin powder, 0.08-0.12 parts of cloves, and 20-25 parts of xylitol.

5. The manufacturing method according to claim 3, characterized in that: The stir-frying in step (4) is to stir-fry over high heat for 2 to 3 minutes.

6. The method according to claim 3, characterized in that: Step (2) is specifically as follows: after the eggs are boiled, reduce the heat and continue to cook for 2-3 minutes, then stop heating and simmer for 2-3 minutes until the eggs are cooked.

7. The manufacturing method according to claim 3, characterized in that: In step (5), while the eggs are being cooked over low heat, the eggs are flipped after being cooked for 15 to 30 minutes, and then continue to be cooked over low heat for 15 to 30 minutes.

8. The manufacturing method according to claim 3, characterized in that: Step (6) specifically includes stopping heating and soaking for 10 to 20 hours until the eggs are well-seasoned.

9. Bamboo leaf eggs produced by the production method according to any one of claims 1 to 8.

10. A seasoning packet for making bamboo leaf eggs, the seasoning packet comprising: 5-8 parts of dried bamboo leaves or 15-25 parts of fresh bamboo leaves, 4-6 parts of star anise, 8-10 parts of cinnamon, 0.03-0.04 parts of pepper, 20-40 parts of ginger, 200-250 parts of dark soy sauce, 10-15 parts of cumin powder, 0.08-0.12 parts of cloves, and 20-25 parts of xylitol.

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