Rose cubilose cake and preparation method thereof

Abstract

The invention belongs to the technical field of cubilose food, and particularly relates to a rose cubilose cake and a preparation method thereof. The rose cubilose cake is prepared through the processes of segmented enzymolysis, polyphenol modification, gel compounding and the like, and the small-molecule glycopeptide compound is released, so that the acting sites of alpha-glucosidase in intestinal tracts are reduced, and the postprandial blood sugar peak value is delayed; a hydrogen bond network is formed through polyphenol modification, the effective polyphenol proportion is increased, and the contact probability of sugar and alpha-amylase is reduced; the contact site of free sugar and amylase is wrapped by the gel network, so that the sugar decomposition efficiency is reduced, the increase of the blood sugar concentration after the intake of the rose cubilose cake is inhibited, and the glycemic potential is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of bird's nest food, and particularly relates to a rose bird's nest cake and a preparation method thereof. Background Art

[0002] As a traditional Chinese tonic, bird's nest contains various nutritional elements such as protein, amino acids, sialic acid and inorganic salts, etc. It can enhance the human immune system, enhance tissue growth and regeneration, has an anti - hemagglutination effect on influenza virus, and also has the effects of improving intelligence and memory, improving neurodegenerative diseases, anti - inflammation, anti - aging, etc.; rose is sweet and slightly bitter in taste, and has the effects of regulating qi and relieving depression, promoting blood circulation to remove stasis and regulating menstruation and relieving pain. Preparing a rose bird's nest cake with bird's nest and rose as raw materials can nourish yin and moisten the lungs, invigorate the spleen and replenish qi, prevent autumn dryness and lung dryness; accelerate the regeneration and repair of skin cells, and make the skin maintain a healthy, rosy and natural complexion. The traditional eating method usually selects and removes impurities from the bird's nest, and then processes and eats it with other ingredients. The macromolecular protein and functional polysaccharide components in it are difficult to be digested and absorbed by the human body, resulting in a great reduction in nutritional value and poor eating effects.

[0003] Diabetes is a chronic metabolic disease caused by insufficient insulin secretion or impaired insulin action. Diet management, as a key part of the comprehensive treatment of diabetes, plays a crucial role in controlling blood sugar, preventing complications and improving the quality of life of diabetic patients. Therefore, diabetic patients often need to strictly control the intake of sugar. The glycemic index (GI) is an important indicator to measure the impact of food on blood sugar. Low - GI foods usually cause smaller blood sugar fluctuations than high - GI foods. Choosing low - GI foods is particularly important for diabetic patients. However, the existing rose bird's nest cake, as a high - GI food, is usually restricted or even prohibited for diabetic patients. Summary of the Invention

[0004] The purpose of the present invention is to provide a rose bird's nest cake and a preparation method thereof in view of the deficiencies of the prior art, which can meet the healthy diet needs of diabetic patients, will not cause a large increase in post - meal blood sugar after eating, can not only meet the psychological requirements of patients who want to eat desserts, but also help diabetic patients better control blood sugar, so as to solve the above - mentioned technical problems.

[0005] To achieve the above - mentioned technical purpose, the technical solution of the present invention is as follows: A preparation method of a rose bird's nest cake, comprising the following steps: S1. Dissolve the swallow's nest fiber and neutral protease in deionized water, adjust the pH to 7.0 - 7.4, let it stand for 0.5 h, and conduct the first enzymatic hydrolysis; add 0.5 - 1.0 wt% of complex glycosidase based on the swallow's nest fiber, adjust the pH to 5.5 - 5.8, let it stand for 1.5 h, and conduct the second enzymatic hydrolysis. After the enzymatic hydrolysis is completed, obtain the hydrolyzed solution of the swallow's nest; inactivate the hydrolyzed solution of the swallow's nest by pulsed electric field, after filtration, add N-acetylcysteine and gellan gum, stir at low temperature for 15 min and then let it stand to obtain a transparent frozen swallow's nest colloid; S2. Prepare the DES solvent with choline chloride and citric acid as raw materials, use the DES solvent to extract polyphenols from the freeze-dried rose petals after pretreatment to obtain a mixed solution of polyphenol extraction from rose petals; pass the mixed solution of polyphenol extraction from rose petals through a resin column for separation and purification, and conduct drying sublimation after the elution is completed until the water content of the powder is ≤ 3% to obtain rose petal polyphenol powder; S3. Dissolve the rose petal polyphenol powder in absolute ethanol according to a mass ratio of 1:1, add resistant dextrin and β-cyclodextrin, stir and mix at 20 rpm at 4℃ for 30 min, after the reaction is completed, dry at 35℃ for 6 h to obtain modified rose petal polyphenol powder; among them, the addition amounts of resistant dextrin and β-cyclodextrin are 12 wt% and 3 wt% of the rose petal polyphenol powder respectively; S4. Pour the swallow's nest colloid into the bottom layer of the pastry mold and refrigerate at low temperature for 2 h for shaping; stir and homogenize the mixture of the modified rose petal polyphenol powder and arabic gum at 300 rpm for 2 min, after preheating at 50℃, uniformly coat it on the shaped swallow's nest colloid at a speed of 0.5 mm / s, let it stand at low temperature for 2 h, and cut it to obtain rose swallow's nest cake.

[0006] As a further improvement, in step S1, the preparation method of the swallow's nest fiber is: immerse the dry swallow's nest in a 0.5 wt% sodium bicarbonate solution with a pH of 8.5 according to a mass ratio of 1:100, let it stand in a water bath at 40℃ for 30 min, conduct ultrasonic treatment at 28 kHz until the diameter of the swallow's nest filaments is reduced to 50 - 100 μm, and then wash with deionized water to obtain the swallow's nest fiber.

[0007] As a further improvement, in step S1, the mass ratio of the swallow's nest fiber to the neutral protease is 150:1 - 5; the complex glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1; the addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 5 - 8 wt% of the hydrolyzed solution of the swallow's nest respectively.

[0008] As a further improvement, in step S2, the pretreatment method of the freeze-dried rose petals is: mix 30 wt% ethanol solution and food-grade lactic acid according to a volume ratio of 4:1, add the freeze-dried rose petals according to a solid-liquid ratio of 1:12 - 15, stir at 200 rpm for 45 min to obtain the pretreated freeze-dried rose petals.

[0009] As a further improvement, the preparation method of the freeze-dried rose petals is as follows: Take fresh double-petal red roses, after cleaning, centrifuge at 500 rpm for 3 minutes, freeze-dry at -80 °C under vacuum for 4 hours. After freezing, under a vacuum of 10 Pa, increase the temperature from -80 °C to 25 °C step by step at a heating rate of 2.5 °C / h, grind and crush, then pass through an 80-mesh sieve, take the powder under the sieve, mix it evenly with vitamin C to obtain the freeze-dried rose petals; the addition amount of vitamin C is 0.1 wt% of the powder under the sieve.

[0010] As a further improvement, in step S2, the specific method for separating and purifying the rose petal polyphenol extraction mixture is as follows: First, pass through an LX-68 resin pretreatment column with a packing height of 1.2 m, a sample loading flow rate of 1.2 mL / min, and elute with 30 wt% ethanol at an elution flow rate of 1.5 mL / min; then pass through the main separation column. The main separation column includes HPD-826 and AB-8, with an HPD-826 layer of 0.8 m and an AB-8 layer of 0.4 m. Quartz sand is filled at the interface to prevent mixing, and elute with 70 wt% ethanol at an elution flow rate of 1.0 mL / min.

[0011] As a further improvement, in step S2, the specific drying and sublimation process is as follows: Pre-freeze the separated and purified rose petal polyphenol extraction mixture at -40 °C for 2 hours. After freezing, under a vacuum of 10 Pa, increase the temperature from -40 °C to 25 °C step by step at a heating rate of 2.5 °C / h, and finally dry at 35 °C for 4 hours.

[0012] As a further improvement, in step S4, the preparation method of the arabic gum mixture is as follows: Dissolve arabic gum in deionized water according to a mass ratio of 1:90, stir in a water bath at 80 °C for 55 minutes, add erythritol and stevioside, and stir and homogenize at 5000 rpm in a water bath at 50 °C for 3 minutes to obtain the arabic gum mixture; among them, the mass ratio of arabic gum, erythritol, and stevioside is 15 - 18:30:0.2.

[0013] Due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The method of segmented enzymatic hydrolysis is adopted. First, neutral protease is used to decompose the glycoprotein in bird's nest into peptide segments of 5-10 kDa, and then a composite glycosidase is used for secondary enzymatic hydrolysis. The β-glucosidase in the composite glycosidase selectively cleaves the O-glycosidic bond in the glycoprotein in bird's nest and releases free sialic acid. The free sialic acid exists in the non-reducing end form and cannot be directly absorbed by the intestine. It needs to be fermented by colonic flora to slowly release energy, which can delay the peak postprandial blood glucose level to 90 min. The α-mannosidase in the composite glycosidase decomposes the N-glycan core in the glycoprotein in bird's nest and releases small molecule glycopeptide complexes. The sugar chain length can be shortened to 2-3 monosaccharide residues (traditional bird's nest contains 5-8), reducing the action sites of intestinal α-glucosidase and lowering the blood glucose-raising potential after the intake of rose bird's nest cake.

[0014] 2. Resistant dextrin forms a complex by wrapping polyphenols through a hydrogen bond network, reducing the destruction of polyphenols by gastric acid or premature release. After entering the small intestine, the polyphenols are released through pH response and co-adsorb on the surface of free sugars in the rose bird's nest cake with resistant dextrin to form a physical barrier, reducing the contact probability with α-amylase. The polyphenols target and inhibit the active center of α-glucosidase, jointly inhibiting the increase in blood glucose concentration.

[0015] 3. Gum arabic is compounded with gellan gum in bird's nest to form a three-dimensional gel system network structure, wrapping the contact sites of free sugars in bird's nest and rose petals with amylase and reducing the sugar decomposition efficiency. After gum arabic is fermented by intestinal flora to generate short-chain fatty acids, it can directly inhibit hepatic gluconeogenesis and reduce hepatic glucose output. Erythritol and steviol glycosides act synergistically. As a zero-calorie sweetener, it does not participate in sugar metabolism, and steviol glycosides can inhibit the activity of intestinal α-glucosidase and reduce glucose absorption, jointly resisting the increase in blood glucose concentration. Specific implementation mode

[0016] The technical solutions of the present invention will be clearly and completely described below in conjunction with specific implementation modes. However, those skilled in the art will understand that the following described embodiments are some embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention. Those not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. Those reagents or instruments not specified in the manufacturer are all conventional products that can be obtained through commercial purchase.

[0017] Example 1 A preparation method of rose bird's nest cake, comprising the following steps: 1. Immerse dry bird's nest in a 0.5 wt% sodium bicarbonate solution with a pH of 8.5 at a mass ratio of 1:100. Let it stand still in a water bath at 40 °C for 30 min, and then perform ultrasonic treatment at 28 kHz until the diameter of the bird's nest filaments is reduced to 50 μm. After that, wash it with deionized water to remove the dissolved impurities and alkaline residues, obtaining bird's nest filament fibers.

[0018] 2. Take 15 g of bird's nest filament fibers and 0.1 g of neutral protease. At a solid-liquid ratio of 1:100, dissolve the bird's nest filament fibers and neutral protease in deionized water, and adjust the pH to 7.0 with ammonia water. Let it stand still for enzymatic hydrolysis for 0.5 h; add 0.5 wt% of complex glycosidase based on the bird's nest filament fibers, adjust the pH to 5.5 with acetic acid, and let it stand still for enzymatic hydrolysis for 1.5 h. After the enzymatic hydrolysis is completed, obtain the bird's nest enzymatic hydrolysate; inactivate the bird's nest enzymatic hydrolysate by pulsed electric field with a field strength of 25 kV / cm for 50 times, filter it, add N-acetylcysteine and gellan gum, stir at 4 °C for 15 min, and let it stand still at 3 °C for 6 h to obtain a transparent frozen bird's nest colloid; among them, the complex glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1; the addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 5 wt% of the bird's nest enzymatic hydrolysate respectively.

[0019] 3. Wash fresh double-petal red roses and centrifuge them at 500 rpm for 3 min, then freeze-dry them at -80 °C under vacuum for 4 h. After freezing, under a vacuum of 10 Pa, increase the temperature from -80 °C to 25 °C step by step at a heating rate of 2.5 °C / h, grind and crush them, and pass them through an 80-mesh sieve. Take the powder under the sieve, and mix it evenly with vitamin C to obtain freeze-dried rose petal powder; among them, the addition amount of the vitamin C is 0.1 wt% of the powder under the sieve.

[0020] 4. Mix a 30 wt% ethanol solution and food-grade lactic acid at a volume ratio of 4:1, add the freeze-dried rose petal powder at a solid-liquid ratio of 1:12, and stir at 200 rpm for 45 min to obtain the pretreated freeze-dried rose petal powder; mix choline chloride and citric acid at a molar ratio of 1:2, perform water bath at 70 °C and stir at 500 rpm for 30 min to form a transparent liquid, add deionized water to reduce the viscosity, and the volume ratio of deionized water to the obtained transparent liquid is 30:1 to obtain the DES solvent; mix the pretreated freeze-dried rose petal powder and the DES solvent at a mass ratio of 1:1, perform ultrasonic-assisted dispersion at 45 °C and 40 kHz for 5 min, stir at 300 rpm for 20 min, and then increase the temperature step by step to 60 °C at a heating rate of 1 °C / min and keep it warm for 2 h; after the heat preservation is completed, the leaching solution is rotary evaporated at 60 °C and -0.09 MPa to recover the excess DES solvent, and cycle 3 times, and supplement 5 wt% of fresh citric acid for each cycle batch; after the cycle is completed, obtain the rose petal polyphenol leaching mixture.

[0021] 5. Separate and purify the polyphenol extraction mixture of rose petals. Pass the polyphenol extract of rose petals through an LX-68 resin pretreatment column with a packing height of 1.2 m, a sample loading flow rate of 1.2 mL / min, and elute with 30 wt% ethanol at an elution flow rate of 1.5 mL / min; then pass through the main separation column, with a 0.8 m layer of HPD-826 and a 0.4 m layer of AB-8, and fill the interface with quartz sand to prevent mixing, and elute with 70 wt% ethanol at an elution flow rate of 1.0 mL / min.

[0022] 6. Pre-freeze the separated and purified polyphenol extraction mixture of rose petals at -40 °C for 2 h. After the freezing is completed, under a vacuum of 10 Pa, increase the temperature stepwise from -40 °C to 25 °C at a heating rate of 2.5 °C / h, and finally dry at 35 °C for 4 h until the water content of the powder is ≤ 3% to obtain rose petal polyphenol powder.

[0023] 7. Dissolve the rose petal polyphenol powder in absolute ethanol at a mass ratio of 1:1, add resistant dextrin and β-cyclodextrin, and stir and mix at 20 rpm for 30 min at 4 °C. After the reaction is completed, dry at 35 °C for 6 h to obtain modified rose petal polyphenol powder; among them, the addition amounts of resistant dextrin and β-cyclodextrin are 12 wt% and 3 wt% of the rose petal polyphenol powder respectively.

[0024] 8. Dissolve gum arabic in deionized water at a mass ratio of 1:90, stir in a water bath at 80 °C for 55 min, add erythritol and stevioside, and stir and homogenize at 5000 rpm for 3 min in a water bath at 50 °C to obtain a gum arabic mixture; among them, the mass ratio of gum arabic, erythritol and stevioside is 15:30:0.2.

[0025] 9. Pour the bird's nest colloid into the bottom layer of the pastry mold with a thickness of 1 cm, refrigerate at 3 °C for 2 h for shaping, then mix the modified rose petal polyphenol powder and the gum arabic mixture, stir and homogenize at 300 rpm for 2 min, preheat at 50 °C, and then evenly coat on the shaped bird's nest colloid at a speed of 0.5 mm / s. Transfer to a low-temperature environment at 4 °C and let it stand for 2 h. After the gel network is completely cross-linked, use a 28 kHz ultrasonic cutting knife to cut it into standard blocks of 20×20×2 cm³ with burrs on the edge ≤ 0.1 mm to obtain rose bird's nest cake.

[0026] Example 2 A preparation method of rose bird's nest cake, comprising the following steps: 1. Immerse dry bird's nest in a 0.5 wt% sodium bicarbonate solution with a pH of 8.5 at a mass ratio of 1:100, stand in a water bath at 40 °C for 30 min, and perform ultrasonic treatment at 28 kHz until the diameter of the bird's nest filaments is reduced to 80 μm, then wash with deionized water to remove the dissolved impurities and alkaline residues to obtain bird's nest filaments.

[0027] 2. Take 15 g of swallow's nest fiber and 0.3 g of neutral protease. According to the material-liquid ratio of 1:100, dissolve the swallow's nest fiber and neutral protease in deionized water, adjust the pH to 7.2 with ammonia water, and let it stand for enzymatic hydrolysis for 0.5 h; add 0.8 wt% of complex glycosidase based on the swallow's nest fiber, adjust the pH to 5.6 with acetic acid, and let it stand for enzymatic hydrolysis for 1.5 h. After the enzymatic hydrolysis is completed, obtain the hydrolyzed solution of the swallow's nest; inactivate the hydrolyzed solution of the swallow's nest by pulsed electric field with a field strength of 25 kV / cm for 50 times, filter it, add N-acetylcysteine and gellan gum, stir at 4°C for 15 min, and then let it stand at 3°C for 6 h to obtain a transparent frozen swallow's nest colloid; among them, the complex glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1. The addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 6 wt% of the hydrolyzed solution of the swallow's nest respectively.

[0028] 3. Wash the fresh double-petal red roses and centrifuge them at 500 rpm for 3 min, freeze-dry them at -80°C for 4 h under vacuum. After the freezing is completed, under a vacuum of 10 Pa, increase the temperature stepwise from -80°C to 25°C at a heating rate of 2.5°C / h, grind and crush them, and pass them through an 80-mesh sieve. Take the powder under the sieve, mix it evenly with vitamin C to obtain the freeze-dried powder of rose petals; among them, the addition amount of vitamin C is 0.1 wt% of the powder under the sieve.

[0029] 4. Mix the 30 wt% ethanol solution and food-grade lactic acid according to the volume ratio of 4:1, add the freeze-dried powder of rose petals according to the solid-liquid ratio of 1:14, and stir at 200 rpm for 45 min to obtain the pretreated freeze-dried powder of rose petals; mix choline chloride and citric acid according to the molar ratio of 1:2, heat them in a water bath at 70°C and stir at 500 rpm for 30 min to form a transparent liquid, add deionized water to reduce the viscosity, and the volume ratio of deionized water to the obtained transparent liquid is 30:1 to obtain the DES solvent; mix the pretreated freeze-dried powder of rose petals and the DES solvent according to the mass ratio of 1:1.3, disperse them by ultrasonic wave at 45°C and 40 kHz for 5 min, stir at 300 rpm for 20 min, and then increase the temperature stepwise to 60°C at a heating rate of 1°C / min and keep it warm for 2 h; after the heat preservation is completed, the leaching solution is rotary evaporated at 60°C and -0.09 MPa to recover the excess DES solvent, and the cycle is repeated 3 times. Each cycle batch is supplemented with 5 wt% of fresh citric acid; after the cycle is completed, obtain the mixed leaching solution of rose petal polyphenols.

[0030] 5. Separate and purify the polyphenol extraction mixture of rose petals. Pass the polyphenol extract of rose petals through a pre-treatment column of LX-68 resin with a packing height of 1.2 m, a sample loading flow rate of 1.2 mL / min, and elute with 30 wt% ethanol at an elution flow rate of 1.5 mL / min; then pass through the main separation column, with a layer of HPD-826 of 0.8 m and a layer of AB-8 of 0.4 m, and fill the interface with quartz sand to prevent mixing, and elute with 70 wt% ethanol at an elution flow rate of 1.0 mL / min.

[0031] 6. Pre-freeze the separated and purified polyphenol extraction mixture of rose petals at -40 °C for 2 h. After the freezing is completed, under a vacuum of 10 Pa, increase the temperature stepwise from -40 °C to 25 °C at a heating rate of 2.5 °C / h, and finally dry at 35 °C for 4 h until the water content of the powder is ≤ 3% to obtain rose petal polyphenol powder.

[0032] 7. Dissolve the rose petal polyphenol powder in anhydrous ethanol according to a mass ratio of 1:1, add resistant dextrin and β-cyclodextrin, and stir and mix at 20 rpm for 30 min at 4 °C. After the reaction is completed, dry at 35 °C for 6 h to obtain modified rose petal polyphenol powder; among them, the addition amounts of resistant dextrin and β-cyclodextrin are 12 wt% and 3 wt% of the modified rose petal polyphenol powder respectively.

[0033] 8. Dissolve gum arabic in deionized water according to a mass ratio of 1:90, stir in a water bath at 80 °C for 55 min, add erythritol and stevioside, and stir and homogenize at 5000 rpm for 3 min in a water bath at 50 °C to obtain a gum arabic mixture; among them, the mass ratio of gum arabic, erythritol and stevioside is 18:30:0.2.

[0034] 9. Pour the bird's nest colloid into the bottom layer of the pastry mold with a thickness of 1 cm, refrigerate at 3 °C for 2 h for shaping, then mix the modified rose petal polyphenol powder and the gum arabic mixture, stir and homogenize at 300 rpm for 2 min, preheat at 50 °C, and then uniformly coat on the shaped bird's nest colloid at a speed of 0.5 mm / s, transfer to a low-temperature environment at 4 °C and let it stand for 2 h. After the gel network is completely cross-linked, use a 28 kHz ultrasonic cutting knife to cut it into standard blocks of 20×20×2 cm³ with burrs on the edge ≤ 0.1 mm to obtain rose bird's nest cake.

[0035] Example 3 A preparation method of rose bird's nest cake, comprising the following steps: 1. Immerse dry bird's nest in a 0.5 wt% sodium bicarbonate solution with a pH of 8.5 according to a mass ratio of 1:100, stand in a water bath at 40 °C for 30 min, perform ultrasonic treatment at 28 kHz until the diameter of the bird's nest filaments is reduced to 100 μm, then wash with deionized water to remove the dissolved impurities and alkaline residues to obtain bird's nest filaments.

[0036] 2. Take 15 g of swallow nest fiber and 0.5 g of neutral protease. According to the material-liquid ratio of 1:100, dissolve the swallow nest fiber and neutral protease in deionized water, adjust the pH to 7.4 with ammonia water, and let it stand for enzymatic hydrolysis for 0.5 h; add 1.0 wt% of complex glycosidase based on the swallow nest fiber, adjust the pH to 5.8 with acetic acid, and let it stand for enzymatic hydrolysis for 1.5 h. After the enzymatic hydrolysis is completed, obtain the hydrolyzed solution of the swallow nest; inactivate the hydrolyzed solution of the swallow nest by pulsed electric field with an electric field strength of 25 kV / cm for 50 times. After filtration, add N-acetylcysteine and gellan gum, stir at 4°C for 15 min, and then let it stand at 3°C for 6 h to obtain a transparent frozen swallow nest colloid; among them, the complex glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1; the addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 8 wt% of the hydrolyzed solution of the swallow nest respectively.

[0037] 3. Wash the fresh double-petal red roses and centrifuge them at 500 rpm for 3 min, freeze-dry them at -80°C for 4 h under vacuum. After freezing, under a vacuum of 10 Pa, increase the temperature stepwise from -80°C to 25°C at a heating rate of 2.5°C / h, grind and crush them, and pass them through an 80-mesh sieve. Take the powder under the sieve, mix it evenly with vitamin C to obtain the freeze-dried powder of rose petals; among them, the addition amount of the vitamin C is 0.1 wt% of the powder under the sieve.

[0038] 4. Mix 30 wt% ethanol solution and food-grade lactic acid according to the volume ratio of 4:1, add the freeze-dried powder of rose petals according to the solid-liquid ratio of 1:15, and stir at 200 rpm for 45 min to obtain the pretreated freeze-dried powder of rose petals; mix choline chloride and citric acid according to the molar ratio of 1:2, heat them in a water bath at 70°C and stir at 500 rpm for 30 min to form a transparent liquid, add deionized water to reduce the viscosity, and the volume ratio of deionized water to the obtained transparent liquid is 30:1 to obtain the DES solvent; mix the pretreated freeze-dried powder of rose petals and the DES solvent according to the mass ratio of 1:1.5, disperse them in a water bath at 45°C with 40 kHz ultrasonic assistance for 5 min, stir at 300 rpm for 20 min, and then increase the temperature stepwise to 60°C at a heating rate of 1°C / min and keep it warm for 2 h; after the heat preservation is completed, the leaching solution is rotary evaporated at 60°C and -0.09 MPa to recover the excess DES solvent, and the cycle is carried out 3 times. Each cycle batch is supplemented with 5 wt% of fresh citric acid; after the cycle is completed, obtain the mixed solution of polyphenol extraction from rose petals.

[0039] 5. Separate and purify the polyphenol extraction mixture of rose petals. Pass the polyphenol extract of rose petals through the LX-68 resin pretreatment column with a packing height of 1.2 m, a sample loading flow rate of 1.2 mL / min, and elute with 30 wt% ethanol at an elution flow rate of 1.5 mL / min; then pass through the main separation column, with 0.8 m of HPD-826 layer and 0.4 m of AB-8 layer, and fill quartz sand at the interface to prevent mixing, and elute with 70 wt% ethanol at an elution flow rate of 1.0 mL / min.

[0040] 6. Pre-freeze the separated and purified polyphenol extraction mixture of rose petals at -40 °C for 2 h. After the freezing is completed, under a vacuum of 10 Pa, with a heating rate of 2.5 °C / h, stepwise heat from -40 °C to 25 °C, and finally dry at 35 °C for 4 h until the water content of the powder is ≤ 3% to obtain rose petal polyphenol powder.

[0041] 7. Dissolve the rose petal polyphenol powder in absolute ethanol at a mass ratio of 1:1, add resistant dextrin and β-cyclodextrin, stir and mix at 4 °C and 20 rpm for 30 min. After the reaction is completed, dry at 35 °C for 6 h to obtain modified rose petal polyphenol powder; among them, the addition amounts of resistant dextrin and β-cyclodextrin are 12 wt% and 3 wt% of the modified rose petal polyphenol powder respectively.

[0042] 8. Dissolve gum arabic in deionized water at a mass ratio of 1:90, stir in a water bath at 80 °C for 55 min, add erythritol and stevioside, and stir and homogenize at 50 °C and 5000 rpm for 3 min to obtain a gum arabic mixture; among them, the mass ratio of gum arabic, erythritol and stevioside is 18:30:0.2.

[0043] 9. Pour the bird's nest colloid into the bottom layer of the pastry mold with a thickness of 1 cm, refrigerate at 3 °C for 2 h for shaping, then mix the modified rose petal polyphenol powder and the gum arabic mixture, stir and homogenize at 300 rpm for 2 min, preheat at 50 °C, and then uniformly coat on the shaped bird's nest colloid at a speed of 0.5 mm / s, transfer to a low-temperature environment at 4 °C and let stand for 2 h. After the gel network is completely cross-linked, use a 28 kHz ultrasonic cutting knife to cut into 20×20×2 cm³ standard blocks with edge burrs ≤ 0.1 mm to obtain rose bird's nest cakes.

[0044] Comparative Example 1 A preparation method of rose bird's nest cakes, which is different from Example 1 in that the compounding of gum arabic and gellan gum is not carried out, specifically as follows: 1. Immerse dry bird's nest in a 0.5 wt% sodium bicarbonate solution with a pH of 8.5 at a mass ratio of 1:100, let it stand in a water bath at 40 °C for 30 min, and perform 28 kHz ultrasonic treatment until the diameter of the bird's nest filaments is reduced to 50 μm, then wash with deionized water to remove the dissolved impurities and alkaline residues to obtain bird's nest filament fibers.

[0045] 2. Take 15 g of swallow's nest fiber and 0.1 g of neutral protease. According to the material-liquid ratio of 1:100, dissolve the swallow's nest fiber and neutral protease in deionized water, adjust the pH to 7.0 with ammonia water, and let it stand for enzymatic hydrolysis for 0.5 h; add 0.5 wt% of composite glycosidase based on the swallow's nest fiber, adjust the pH to 5.5 with acetic acid, and let it stand for enzymatic hydrolysis for 1.5 h. After the enzymatic hydrolysis is completed, obtain the hydrolyzed solution of the bird's nest; the hydrolyzed solution of the bird's nest is inactivated by pulsed electric field with an electric field strength of 25 kV / cm for 50 times, filtered, then add N-acetylcysteine and gellan gum, stir at 4 °C for 15 min, and then let it stand at 3 °C for 6 h to obtain a transparent frozen bird's nest colloid; among them, the composite glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1; the addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 5 wt% of the hydrolyzed solution of the bird's nest respectively.

[0046] 3. Wash the fresh double-petal red roses and centrifuge them at 500 rpm for 3 min, freeze-dry them at -80 °C under vacuum for 4 h. After freezing, under a vacuum of 10 Pa, increase the temperature stepwise from -80 °C to 25 °C at a heating rate of 2.5 °C / h, grind and crush them, and pass through an 80-mesh sieve. Take the powder under the sieve, mix it evenly with vitamin C to obtain the freeze-dried powder of rose petals; among them, the addition amount of the vitamin C is 0.1 wt% of the powder under the sieve.

[0047] 4. Mix the 30 wt% ethanol solution and food-grade lactic acid according to the volume ratio of 4:1, add the freeze-dried powder of rose petals according to the solid-liquid ratio of 1:12, and stir at 200 rpm for 45 min to obtain the pretreated freeze-dried powder of rose petals; mix choline chloride and citric acid according to the molar ratio of 1:2, heat in a water bath at 70 °C and stir at 500 rpm for 30 min to form a transparent liquid, add deionized water to reduce the viscosity, and the volume ratio of deionized water to the obtained transparent liquid is 30:1 to obtain the DES solvent; mix the pretreated freeze-dried powder of rose petals and the DES solvent according to the mass ratio of 1:1, disperse them in a water bath at 45 °C with 40 kHz ultrasonic assistance for 5 min, stir at 300 rpm for 20 min, and then increase the temperature stepwise to 60 °C at a heating rate of 1 °C / min, and keep it warm for 2 h; after the heat preservation is completed, the leaching solution is rotary evaporated at 60 °C and -0.09 MPa to recover the excess DES solvent, and the cycle is repeated 3 times. Each cycle batch is supplemented with 5 wt% of fresh citric acid; after the cycle is completed, obtain the mixed extract of rose petal polyphenols.

[0048] 5. Separate and purify the mixed extract of rose petal polyphenols. Pass the rose petal polyphenol extract through the LX-68 resin pretreatment column with a packing height of 1.2 m, and the sample loading flow rate is 1.2 mL / min. Elute with 30 wt% ethanol, and the elution flow rate is 1.5 mL / min; then pass through the main separation column, with 0.8 m of HPD-826 layer and 0.4 m of AB-8 layer, and fill quartz sand at the interface to prevent mixing. Elute with 70 wt% ethanol, and the elution flow rate is 1.0 mL / min.

[0049] 6. Pre-freeze the separated and purified rose petal polyphenol extraction mixture at -40°C for 2 h. After the freezing is completed, under a vacuum of 10 Pa, increase the temperature stepwise from -40°C to 25°C at a heating rate of 2.5°C / h, and finally dry at 35°C for 4 h until the water content of the powder is ≤ 3% to obtain rose petal polyphenol powder.

[0050] 7. Dissolve the rose petal polyphenol powder in absolute ethanol at a mass ratio of 1:1, add resistant dextrin and β-cyclodextrin, and stir and mix at 20 rpm for 30 min at 4°C. After the reaction is completed, dry at 35°C for 6 h to obtain modified rose petal polyphenol powder; among them, the addition amounts of resistant dextrin and β-cyclodextrin are 12 wt% and 3 wt% of the modified rose petal polyphenol powder, respectively.

[0051] 8. Mix the bird's nest colloid with the modified rose petal polyphenol powder, stir and homogenize at 300 rpm for 2 min, with a thickness of 1 cm, refrigerate at 3°C for 2 h for shaping, and then cut into 20×20×2 cm³ standard blocks with a 28 kHz ultrasonic cutting knife, and the edge burrs ≤ 0.1 mm to obtain rose bird's nest cake.

[0052] Comparative Example 2 A preparation method of rose bird's nest cake, which is different from Example 1 in that the bird's nest is not enzymolyzed, specifically as follows: 1. Immerse the dry bird's nest in a 0.5 wt% sodium bicarbonate solution with a pH of 8.5 at a mass ratio of 1:100, stand still in a water bath at 40°C for 30 min, perform 28 kHz ultrasonic treatment until the diameter of the bird's nest filaments is reduced to 50 μm, then wash with deionized water to remove the dissolved impurities and alkaline residues to obtain bird's nest filaments; add N-acetylcysteine and gellan gum, stir at low temperature at 4°C for 15 min, and then stand still at 3°C for 6 h to obtain a transparent frozen bird's nest colloid; among them, the addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 5 wt% of the bird's nest enzymolysis solution, respectively.

[0053] 2. After washing the fresh double-petal red roses, centrifuge and separate at 500 rpm for 3 min, freeze-dry at -80°C under vacuum for 4 h. After the freezing is completed, under a vacuum of 10 Pa, increase the temperature stepwise from -80°C to 25°C at a heating rate of 2.5°C / h, grind and crush, and then pass through an 80-mesh sieve. Take the powder under the sieve and mix it evenly with vitamin C to obtain rose petal freeze-dried powder; among them, the addition amount of the vitamin C is 0.1 wt% of the powder under the sieve.

[0054] 3. Mix the 30 wt% ethanol solution and food-grade lactic acid in a volume ratio of 4:1, add freeze-dried rose petals powder at a solid-liquid ratio of 1:12, stir at 200 rpm for 45 min to obtain the pretreated freeze-dried rose petals powder; mix choline chloride and citric acid in a molar ratio of 1:2, heat in a water bath at 70 °C and stir at 500 rpm for 30 min to form a transparent liquid, add deionized water to reduce the viscosity, and the volume ratio of deionized water to the obtained transparent liquid is 30:1 to obtain the DES solvent; mix the pretreated freeze-dried rose petals powder and the DES solvent in a mass ratio of 1:1, disperse ultrasonically at 45 °C and 40 kHz for 5 min, stir at 300 rpm for 20 min, then heat at a heating rate gradient of 1 °C / min to 60 °C and keep warm for 2 h; after the heat preservation ends, the leaching solution is rotary evaporated at 60 °C and -0.09 MPa to recover the excess DES solvent, cycle 3 times, and supplement 5 wt% of fresh citric acid for each cycle batch; after the cycle ends, obtain the rose petal polyphenol leaching mixture.

[0055] 4. Separate and purify the rose petal polyphenol leaching mixture. Pass the rose petal polyphenol extract through the LX-68 resin pretreatment column with a packing height of 1.2 m and a sample loading flow rate of 1.2 mL / min, and elute with 30 wt% ethanol with an elution flow rate of 1.5 mL / min; then pass through the main separation column with 0.8 m of HPD-826 layer and 0.4 m of AB-8 layer, and fill quartz sand at the interface to prevent mixing, and elute with 70 wt% ethanol with an elution flow rate of 1.0 mL / min.

[0056] 5. Pre-freeze the separated and purified rose petal polyphenol leaching mixture at -40 °C for 2 h. After the freezing ends, under a vacuum of 10 Pa, heat from -40 °C to 25 °C at a heating rate of 2.5 °C / h in a stepped manner, and finally dry at 35 °C for 4 h until the water content of the powder is ≤ 3% to obtain the rose petal polyphenol powder.

[0057] 6. Dissolve the rose petal polyphenol powder in absolute ethanol in a mass ratio of 1:1, add resistant dextrin and β-cyclodextrin, stir and mix at 20 rpm at 4 °C for 30 min, and after the reaction ends, dry at 35 °C for 6 h to obtain the modified rose petal polyphenol powder; among them, the addition amounts of resistant dextrin and β-cyclodextrin are 12 wt% and 3 wt% of the modified rose petal polyphenol powder respectively.

[0058] 7. Dissolve arabic gum in deionized water in a mass ratio of 1:90, stir in a water bath at 80 °C for 55 min, add erythritol and stevioside, and stir and homogenize at 5000 rpm in a water bath at 50 °C for 3 min to obtain the arabic gum mixture; among them, the mass ratio of arabic gum, erythritol and stevioside is 15:30:0.2.

[0059] 8. Pour the bird's nest colloid into the bottom layer of the pastry mold with a thickness of 1 cm. After refrigerating at 3°C for 2 h for shaping, mix the modified rose petal polyphenol powder with the arabic gum mixture, stir and homogenize at 300 rpm for 2 min. After preheating at 50°C, evenly coat it on the shaped bird's nest colloid at a speed of 0.5 mm / s, transfer it to a low-temperature environment at 4°C and let it stand for 2 h. After the gel network is completely cross-linked, use a 28 kHz ultrasonic cutting knife to cut it into standard blocks of 20×20×2 cm³ with burrs at the edges ≤0.1 mm to obtain rose bird's nest cakes.

[0060] Comparative Example 3 A preparation method of rose bird's nest cakes, which is different from Example 1 in that the modified rose flower polyphenols are not used to prepare rose bird's nest cakes, and the treated rose petals are directly used for the preparation of rose bird's nest cakes, specifically as follows: 1. Immerse dry bird's nest in a sodium bicarbonate solution with a pH of 8.5 and a concentration of 0.5 wt% according to a mass ratio of 1:100, stand still in a water bath at 40°C for 30 min, and perform ultrasonic treatment at 28 kHz until the diameter of the bird's nest filaments is reduced to 50 ㎛. Then wash with deionized water to remove the dissolved impurities and alkaline residues to obtain bird's nest filament fibers.

[0061] 2. Take 15 g of bird's nest filament fibers and 0.1 g of neutral protease. According to a solid-liquid ratio of 1:100, dissolve the bird's nest filament fibers and neutral protease in deionized water, adjust the pH to 7.0 with ammonia water, and stand still for enzymatic hydrolysis for 0.5 h; add 0.5 wt% of composite glycosidase to the bird's nest filament fibers, adjust the pH to 5.5 with acetic acid, and stand still for enzymatic hydrolysis for 1.5 h. After the enzymatic hydrolysis is completed, obtain the bird's nest enzymatic hydrolysate; the bird's nest enzymatic hydrolysate is pulsed 50 times by a pulsed electric field with an electric field strength of 25 kV / cm for inactivation, filtered, and then N-acetylcysteine and gellan gum are added, stirred at 4°C for 15 min, and stood still at 3°C for 6 h to obtain a transparent frozen bird's nest colloid; among them, the composite glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1; the addition amounts of N-acetylcysteine and gellan gum are 0.1 wt% and 5 wt% of the bird's nest enzymatic hydrolysate, respectively.

[0062] 3. After washing the fresh double-petal red roses, centrifuge them at 500 rpm for 3 min, freeze-dry them at -80°C under vacuum for 4 h. After the freezing is completed, under a vacuum degree of 10 Pa, stepwise heat them from -80°C to 25°C at a heating rate of 2.5°C / h, grind and crush them, and then pass them through an 80-mesh sieve. Take the powder under the sieve and mix it evenly with vitamin C to obtain freeze-dried rose petal powder; among them, the addition amount of the vitamin C is 0.1 wt% of the powder under the sieve.

[0063] 4. Dissolve gum arabic in deionized water at a mass ratio of 1:90, stir in a water bath at 80 °C for 55 min, add erythritol and stevioside, and stir and homogenize at 5000 rpm for 3 min in a water bath at 50 °C to obtain a gum arabic mixture; wherein, the mass ratio of gum arabic, erythritol and stevioside is 15:30:0.2.

[0064] 5. Pour the bird's nest colloid into the bottom layer of the pastry mold with a thickness of 1 cm, refrigerate at 3 °C for 2 h for shaping, then mix the freeze-dried rose petals with the gum arabic mixture, stir and homogenize at 300 rpm for 2 min, preheat at 50 °C, and then uniformly coat it on the shaped bird's nest colloid at a speed of 0.5 mm / s. Transfer it to a low-temperature environment at 4 °C and let it stand for 2 h. After the gel network is completely cross-linked, use a 28 kHz ultrasonic cutting knife to cut it into 20×20×2 cm³ standard blocks with burrs on the edge ≤0.1 mm to obtain rose bird's nest cakes.

[0065] Administer the rose bird's nest cakes obtained from the above examples to ordinary mice by oral ingestion and detect their glycemic index as follows: Select 60 healthy ordinary mice at 8 weeks old, with 30 males and 30 females, and randomly divide them into 6 groups with 10 mice in each group. Feed them with standard feed for 1 week, maintain a 12 h day-night rhythm, and adapt to the laboratory environment. After 1 week, make the rose bird's nest cakes into particles with a diameter of 3 mm to ensure that the dose of rose bird's nest cakes ingested by each mouse is 300 mg / kg. Detect the fasting blood glucose (FBG) of the mice before taking the rose bird's nest cakes and the change in blood glucose concentration after taking the rose bird's nest cakes. The experimental period is three days, and the average of the three-day test data is taken as the experimental result, as shown in Table 1 and Table 2; determine the glycemic index of the rose bird's nest cakes obtained from each group of examples through an in vitro simulation model, as shown in Table 3.

[0066] Table 1 Fasting blood glucose test results of each group of mice Table 2 Postprandial blood glucose changes of each group of mice Table 3 Glycemic index (GI) of bird's nest rose cakes obtained from different examples As can be seen from Table 2 and Table 3, the peak postprandial blood glucose of Examples 1-3 is delayed to 90 min, while the peak postprandial blood glucose of Comparative Examples 1-3 is advanced to 60 min, confirming that the lack of gel coating, enzymatic hydrolysis of bird's nest or polyphenol modification will all cause the glycemic index of Comparative Examples 1-3 to be higher than that of Examples 1-3. In Comparative Example 1, the lack of gel coating accelerates the rate of glycolysis, resulting in an earlier peak blood glucose; in Comparative Example 2, the bird's nest was not enzymatically hydrolyzed; in Comparative Example 3, the lack of modified polyphenols binding to α-amylase accelerates the decomposition of carbohydrates, accelerating the increase in blood glucose concentration in the blood.

[0067] The specific embodiments of the present invention described above do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and deformations made according to the technical concept of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A method for preparing rose bird's nest cake, comprising the following steps: S1. Dissolve bird's nest fiber and neutral protease in deionized water, adjust the pH to 7.0-7.4, let stand for 0.5h, and perform primary enzymolysis; add 0.5-1.0wt% of composite glycosidase to bird's nest fiber, adjust the pH to 5.5-5.8, let stand for 1.5h, and perform secondary enzymolysis. After the enzymolysis is completed, a bird's nest enzymolysis solution is obtained; the bird's nest enzymolysis solution is inactivated by a pulse electric field, filtered, and then N-acetylcysteine ​​and gellan gum are added, stirred at low temperature for 15min and then allowed to stand to obtain a transparent frozen bird's nest colloid; S2, using choline chloride and citric acid as raw materials to prepare DES solvent, using DES solvent to extract polyphenols from the pretreated rose petal freeze-dried powder, to obtain a rose petal polyphenol extraction mixture; passing the rose petal polyphenol extraction mixture through a resin column for separation and purification, and drying and sublimating after elution until the water content of the powder is ≤3%, to obtain rose petal polyphenol powder; S3, dissolving rose petal polyphenol powder in anhydrous ethanol at a mass ratio of 1:1, adding resistant dextrin and β-cyclodextrin, stirring and mixing at 20 rpm for 30 min at 4°C, and after the reaction, vacuum drying at 35°C for 6 h to obtain modified rose petal polyphenol powder; wherein the added amounts of resistant dextrin and β-cyclodextrin are 12wt% and 3wt% of the rose petal polyphenol powder, respectively; S4. Pour the bird's nest colloid into the bottom layer of the pastry mold and refrigerate it at low temperature for 2 hours to set it; stir the modified rose petal polyphenol powder and gum arabic at 300 rpm for 2 minutes, preheat it at 50°C, and evenly apply it on the shaped bird's nest colloid at a speed of 0.5 mm / s, let it stand at low temperature for 2 hours, and cut it into rose bird's nest cakes.

2. The method for preparing rose bird's nest cake according to claim 1, characterized in that: In step S1, the preparation method of the bird's nest fiber is as follows: immerse the dry bird's nest in a sodium bicarbonate solution with a pH of 8.5 and 0.5wt% at a mass ratio of 1:100, let it stand in a water bath at 40°C for 30 minutes, and perform ultrasonic treatment at 28kHz until the bird's nest diameter is reduced to 50~100㎛, and then wash it with deionized water to obtain the bird's nest fiber.

3. The method for preparing the rose bird's nest cake according to claim 1, characterized in that: In step S1, the mass ratio of the bird's nest silk fiber to the neutral protease is 150:1~5; the complex glycosidase includes β-glucosidase and α-mannosidase, and the mass ratio of the two is 3:1; the added amounts of N-acetylcysteine ​​and gellan gum are 0.1wt% and 5~8wt% of the bird's nest enzymatic hydrolysate, respectively.

4. The method for preparing the rose bird's nest cake according to claim 1, characterized in that: In step S2, the pretreatment method of the rose petal freeze-dried powder is: mixing 30wt% ethanol solution and food-grade lactic acid at a volume ratio of 4:1, adding rose petal freeze-dried powder at a solid-liquid ratio of 1:12-15, stirring at 200rpm for 45min, to obtain the pretreated rose petal freeze-dried powder.

5. The method for preparing rose bird's nest cake according to claim 4, characterized in that: The preparation method of the rose petal freeze-dried powder is as follows: fresh double-petal red roses are taken, washed, centrifuged at 500 rpm for 3 minutes, freeze-dried at -80°C for 4 hours under vacuum, and after freezing, heated from -80°C to 25°C at a vacuum degree of 10 Pa at a heating rate of 2.5°C / h, ground and crushed, and passed through an 80-mesh sieve, and the powder under the sieve is taken and mixed evenly with vitamin C to obtain the rose petal freeze-dried powder; the added amount of vitamin C is 0.1wt% of the powder under the sieve.

6. The method for preparing rose bird's nest cake according to claim 1, characterized in that: In step S2, the specific method for separating and purifying the rose petal polyphenol extraction mixed liquid is: first pass through an LX-68 resin pretreatment column with a filling height of 1.2m, a loading flow rate of 1.2mL / min, and elute with 30wt% ethanol at an elution flow rate of 1.5mL / min; then pass through a main separation column, the main separation column includes HPD-826 and AB-8, the HPD-826 layer is 0.8m, the AB-8 layer is 0.4m, the interface is filled with quartz sand to prevent mixing, and elute with 70wt% ethanol at an elution flow rate of 1.0mL / min.

7. The method for preparing rose bird's nest cake according to claim 1, characterized in that: In step S2, the drying and sublimation process is specifically as follows: pre-freeze the separated and purified rose petal polyphenol extraction mixture at -40°C for 2 hours, and after freezing, heat it stepwise from -40°C to 25°C at a heating rate of 2.5°C / h under a vacuum degree of 10Pa, and finally dry it at 35°C for 4 hours.

8. The method for preparing rose bird's nest cake according to claim 1, characterized in that: In step S4, the preparation method of the gum arabic mixture is as follows: dissolve gum arabic in deionized water at a mass ratio of 1:90, stir in a water bath at 80°C for 55 minutes, add erythritol and stevioside, and stir and homogenize at 5000 rpm for 3 minutes in a water bath at 50°C to obtain the gum arabic mixture; wherein the mass ratio of gum arabic, erythritol and stevioside is 15~18:30:0.

2.

9. The rose bird's nest cake prepared by the preparation method of the rose bird's nest cake according to claim 1.

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