Chicken heart freeze-dried solid beverage with low hygroscopicity and preparation method of chicken heart freeze-dried solid beverage

Abstract

The invention relates to a chicken heart freeze-dried solid beverage with low hygroscopicity and a preparation method thereof. Comprising the following steps: S1, carrying out squeezing and separation treatment on pretreated chicken heart fruits to obtain chicken heart fruit juice; s2, performing freeze concentration treatment on the juglans regia juice to obtain concentrated juglans regia juice; s3, mixing the concentrated juglans regia juice with low-ester pectin, and performing shearing treatment to obtain a first mixture; s4, mixing calcium chloride, zein, ethanol and water to obtain a second mixture; s5, the first mixture is sprayed into the second mixture, an obtained third mixture is subjected to rotary evaporation treatment to remove ethyl alcohol, then vacuum freeze drying treatment is conducted, and chicken heart powder is obtained; and S6, mixing the chicken heart powder with sodium bicarbonate to obtain the chicken heart freeze-dried solid beverage. The preparation method disclosed by the invention solves the problem of moisture absorption of the chicken heart freeze-dried solid beverage, and the preparation method is simple and suitable for industrial production.

Description

Technical Field

[0001] The present disclosure relates to the technical field of food processing, and in particular to a lyophilized solid beverage of walnut with low hygroscopicity and a preparation method thereof. Background Art

[0002] The heart-shaped fruit is a new variety of excellent small apples, also known as 'Jinxiu Haitang' and 'Saiwai Red Apple'. It has bright color and a sugar content of 16% to 20%, with the characteristics of high sugar and high acid. In recent years, more and more heart-shaped fruit trees have entered the peak fruit-bearing period, and the output of heart-shaped fruit has increased rapidly. Due to the concentrated harvest time, if the mature heart-shaped fruit cannot be sold in time, it will cause huge economic losses and waste of resources. Using mature heart-shaped fruit to produce special heart-shaped fruit products is an important measure to ensure the healthy development of the local heart-shaped fruit industry. Heart-shaped fruit juice freeze-dried powder is a product with high nutritional retention and convenient storage and transportation. After reconstitution, it can become a juice drink with good heart-shaped fruit flavor.

[0003] However, the lyophilized powder of aronia juice has a high sugar content, and it absorbs moisture and lumps during storage, which seriously affects the commercial characteristics of the lyophilized powder of aronia juice. At present, there is no anti-hygroscopic technology for aronia powder. Commonly used anti-hygroscopic agents are additives such as tricalcium phosphate, calcium stearate, and magnesium stearate. For example, patent document 201310138009.4 discloses a method for adding apple powder, which uses silicon dioxide to prevent apple powder from absorbing moisture. However, considering consumers' demand for clean labels and food nutrition, natural food raw materials have become an ideal choice for anti-hygroscopic agents. Patent document CN202010140915.8 discloses a low-hygroscopic apple freeze-dried powder and its preparation, which adds gluten and polysaccharides to reduce the hygroscopicity of apple powder. During the preparation process, the pH of the mixed apple pulp needs to be adjusted to 8-10. However, the pH adjustment process is complicated and difficult to match the solid-acid ratio of the product, and the flavor of the product cannot be guaranteed.

[0004] Zein nanoparticles are a type of hydrophobic material that can be used in food and medicine. They can increase the hydrophobicity of freeze-dried powder and slow down its moisture absorption rate. However, if they are added to fruit juice alone, precipitation may occur, which may affect the product production process.

[0005] In summary, the moisture absorption of chicken heart fruit freeze-dried solid beverage is a problem that needs to be solved urgently. Summary of the invention

[0006] In order to solve the problem of moisture absorption of the lychee jelly-dried solid beverage, the present invention aims to provide a lychee jelly-dried solid beverage with low hygroscopicity and a preparation method thereof.

[0007] In order to achieve the above-mentioned object, the present disclosure provides a first aspect of a method for preparing a lyophilized solid beverage of jellyfish with low hygroscopicity, comprising the following steps: S1, subjecting the pretreated sago palm to a squeezing and separation process to obtain sago palm juice; S2, subjecting the jackfruit juice to freeze concentration treatment to obtain jackfruit concentrated juice; S3, mixing the pineapple concentrated juice and low-ester pectin and performing shearing treatment to obtain a first mixture; S4, mixing calcium chloride, zein, ethanol and water to obtain a second mixture; S5, spraying the first mixture into the second mixture, subjecting the obtained third mixture to vacuum distillation to remove ethanol and then to vacuum freeze-drying to obtain guava powder; S6. Mixing the jackfruit powder with sodium bicarbonate to obtain a jackfruit freeze-dried solid beverage.

[0008] Optionally, in step S3, the weight ratio of the concentrated pineapple juice to low-ester pectin is 100:(0.1-1.0); wherein the degree of esterification of the low-ester pectin is 40-50%; and the low-ester pectin is selected from one or more of citrus pectin, apple pectin and sunflower pectin.

[0009] Optionally, in step S5, a volume ratio of the first mixture to the second mixture is 1:(1-2).

[0010] Optionally, in step S4, the second mixture is prepared by the following method: SS1, mixing calcium chloride, zein, ethanol and water and stirring to obtain a mixed material; SS2. Mixing the mixture with water and then subjecting the mixture to ultrasonic treatment to obtain the second mixture.

[0011] Optionally, in step SS1, the mass ratio of calcium chloride, zein, ethanol and water is 0.25:(1-2):(30-40):(50-80); The stirring conditions include: a rotation speed of 400-600 rpm and a time of 5-10 min; In step SS2, the mass ratio of the mixed material to water is 1:(1-3); The conditions of the ultrasonic treatment include: temperature of 25-30°C, frequency of 40-60 Hz, and time of 20-30 min.

[0012] Optionally, in step S1, the pretreatment includes: selecting fully ripe pineapple, washing, draining, and then crushing.

[0013] Optionally, in step S1, the conditions of the squeezing separation treatment include: a pressure of 5-7 kPa and a time of 1-2 h; In step S2, the freeze concentration treatment conditions include: temperature of (-1)-(-3)°C, scraper speed of 80-100 rpm, stirring speed of the stirrer of 400-600 rpm, concentration time of 1-2 hours; the volume of the concentrated pineapple juice is 1 / 3-2 / 3 of the pineapple juice; In step S3, the shearing treatment conditions include: a shearing speed of 6000-12000 rpm; a time of 3-5 min; In step S5, the conditions of the vacuum freeze-drying treatment include pre-freezing treatment, sublimation drying freezing treatment and analytical drying treatment, wherein the temperature of the pre-freezing treatment is (-80)-(-40)°C, and the time is 6-10h; the temperature of the sublimation drying freezing treatment is (-20)-(-10)°C, the time is 20-30h, and the vacuum degree is 30-100Pa; the temperature of the analytical drying treatment is 30-40°C, the time is 6-8h, and the vacuum degree is 30-100Pa.

[0014] Optionally, in step S6, the mass ratio of the pineapple powder to sodium bicarbonate is 1:(0.1-0.3).

[0015] Optionally, the freeze-dried jellyfish solid beverage with low hygroscopicity has a water content of 0-10%.

[0016] The second aspect of the present disclosure provides a freeze-dried solid beverage of Chinese pomelo prepared by the method described in the first aspect.

[0017] Through the above technical scheme, the present invention utilizes the acidic properties of the concentrated pineapple juice to compound zein nanoparticles and low-ester pectin; at this pH value, the zein nanoparticles, low-ester pectin, and Ca 2+ can undergo electrostatic interactions; more specifically, zein nanoparticles and Ca 2+ Positively charged, low-ester pectin negatively charged, thus forming a stable microcapsule shell on the surface of the lyophilized solid of the heart of chicken fruit, reducing the contact area between the lyophilized solid beverage and the air, and effectively solving the processing industry problem of its easy moisture absorption and agglomeration. At the same time, adding sodium bicarbonate to the lyophilized powder can also adjust the pH after dissolution so that the microcapsule shell of the lyophilized solid beverage of the heart of chicken fruit breaks when it is redissolved, improving the problem of easy precipitation of the lyophilized solid beverage of the heart of chicken fruit. The preparation method disclosed in the present invention solves the problem of moisture absorption of the lyophilized solid beverage of the heart of chicken fruit, and the preparation method is simple and suitable for industrial production.

[0018] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings: Figure 1 The figure shows the changes in water content of the embodiments and comparative examples of the present disclosure during different storage times.

[0020] Figure 2 The figure shows the changes in moisture absorption rate of the embodiments and comparative examples during different storage times.

[0021] Figure 3 Graph 2 shows the change in relaxation time between the embodiments of the present disclosure and the comparative example. DETAILED DESCRIPTION

[0022] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0023] The first aspect of the present disclosure provides a method for preparing a lyophilized solid beverage of jellyfish with low hygroscopicity, comprising the following steps: S1, subjecting the pretreated sago palm to a squeezing and separation process to obtain sago palm juice; S2, subjecting the jackfruit juice to freeze concentration treatment to obtain jackfruit concentrated juice; S3, mixing the pineapple concentrated juice and low-ester pectin and performing shearing treatment to obtain a first mixture; S4, mixing calcium chloride, zein, ethanol and water to obtain a second mixture; S5, spraying the first mixture into the second mixture, subjecting the obtained third mixture to vacuum distillation to remove ethanol and then to vacuum freeze-drying to obtain guava powder; S6. Mixing the jackfruit powder with sodium bicarbonate to obtain a jackfruit freeze-dried solid beverage.

[0024] In the present disclosure, the pH value of the concentrated pineapple juice is generally 3.2-3.8. By utilizing the acidic properties of the concentrated pineapple juice, at this pH value, the zein nanoparticles, Ca 2+ Electrostatic interactions occur with low-ester pectin; more specifically, zein nanoparticles and Ca 2+Positively charged, low-ester pectin negatively charged, thus forming a stable microcapsule shell with a certain hydrophobicity on the surface of the heart of the fruit powder, reducing the contact area between the heart of the fruit powder and the air, and effectively solving the processing industry problem of easy moisture absorption and agglomeration. At the same time, adding sodium bicarbonate to the heart of the fruit powder can also increase the pH of the freeze-dried solid beverage after dissolution, thereby destroying the electrostatic interaction between the three, improving the problem of easy precipitation of the heart of the fruit freeze-dried solid beverage, and making the heart of the fruit freeze-dried solid beverage disperse faster during redissolution. The preparation method disclosed in the present invention solves the problem of moisture absorption of the heart of the fruit freeze-dried solid beverage, and the preparation method is simple and suitable for industrial production.

[0025] In one embodiment of the present disclosure, in step S3, the weight ratio of the concentrated pineapple juice to the low-ester pectin is 100:(0.1-1.0), preferably 100:(0.1-0.5).

[0026] In one embodiment of the present disclosure, in step S5, the volume ratio of the first mixture to the second mixture is 1:(1-2), preferably 1:1. In the present disclosure, the first mixture is sprayed into the second mixture, and the spraying can make the first mixture enter the second mixture in the form of small droplets, which can ensure that the small droplets can form a microcapsule shell, which is more conducive to preventing the heart fruit freeze-dried solid beverage from absorbing water. Spraying can be carried out by instruments conventionally used by those skilled in the art, such as a peristaltic pump. In small batch production, this step can also be carried out by dropwise addition.

[0027] In one embodiment of the present disclosure, the esterification degree of the low-ester pectin is 40-50%. In the above embodiment, the low-ester pectin within the above esterification degree range has more negative charges and is more likely to react with zein nanoparticles, Ca 2+ Electrostatic interaction occurs, thereby forming a more stable hydrophobic layer, thereby further reducing the hygroscopicity of the freeze-dried solid beverage. Optionally, the low-ester pectin can be selected from one or more of citrus pectin, apple pectin and sunflower pectin.

[0028] In one embodiment of the present disclosure, in step S4, the second mixture is prepared by the following method: SS1, mixing calcium chloride, zein, ethanol and water and stirring to obtain a mixed material; SS2. Mixing the mixture with water and then subjecting the mixture to ultrasonic treatment to obtain the second mixture.

[0029] In the present disclosure, the prepared second mixture contains zein nanoparticles and Ca 2+Specifically, zein is dissolved in ethanol, and then water is gradually added as an anti-solvent to reduce the ethanol concentration, thereby reducing the solubility of zein, thereby causing self-assembly to form nanoparticles.

[0030] Furthermore, the first mixture contains low-ester pectin, and the second mixture contains zein nanoparticles and Ca 2+ , zein nanoparticles, Ca 2+ Zein nanoparticles-pectin-Ca 2+ The ternary complex is used as a microcapsule shell to embed the flavor substances and solids in the concentrated pineapple juice, thereby better protecting the flavor substances in the juice. The amount of low-ester pectin added in the present invention is relatively low, and the amount of zein nanoparticles and Ca required to be added is relatively small. 2+ The content is low, but the prepared solid beverage can better retain the flavor substances, and has a good re-dissolution effect and good anti-hygroscopicity, effectively avoiding the zein nanoparticles, Ca 2+ The problem of less complex formation with low-ester pectin, resulting in greater loss of flavor substances, as well as zein nanoparticles, Ca 2+ The problem of excessively high complex formation with low-ester pectin leading to increased hydrophobicity that affects the re-dissolution effect.

[0031] Wherein, in step SS1, the mass ratio of calcium chloride, zein, ethanol and water is 0.25:(1-2):(30-40):(50-80); the stirring treatment conditions include: a rotation speed of 400-600 rpm and a time of 5-10 min. This step can make zein change from alcohol soluble to water soluble.

[0032] In step SS2, the mass ratio of the mixed material to water is 1:(1-3); the conditions of the ultrasonic treatment include: temperature of 25-30°C, frequency of 40-60Hz, and time of 20-30min; this step helps dissolve the mixture.

[0033] In one embodiment of the present disclosure, in step S1, the pretreatment includes: selecting fully mature heart-shaped fruits, washing them, draining them, and then crushing them.

[0034] In one embodiment of the present disclosure, in step S1, the conditions of the pressing and separation treatment include: a pressure of 5-7 kPa and a time of 1-2 h.

[0035] In the present disclosure, before the squeezing and separation process, the heart fruit is generally crushed first, and the crushing process can break the heart fruit into small pieces, thereby increasing the force-bearing area of ​​the heart fruit during the squeezing and separation process. The squeezing and separation process can use instruments conventionally used by those skilled in the art, such as an air bag press.

[0036] In the present disclosure, the freeze concentration process can use a freeze concentrator conventionally used by those skilled in the art, which includes a scraper and a stirrer. The stirrer can make the solution more uniform, and the scraper continuously rotates to scrape ice crystals on the wall of the device to avoid the formation of large ice crystals. In one embodiment of the present disclosure, in step S2, the conditions of the freeze concentration process include: a temperature of (-1)-(-3) ° C, a scraper speed of 80-100 rpm, a stirring speed of the stirrer of 400-600 rpm, and a concentration time of 1-2 hours.

[0037] In a preferred embodiment of the present disclosure, the volume of the convolvulus fruit juice concentrate is 1 / 3-2 / 3 of the convolvulus fruit juice. In the above embodiment, the energy consumption of the subsequent vacuum freeze-drying process can be effectively reduced.

[0038] In one embodiment of the present disclosure, in step S4, the shear treatment conditions include: a shear rate of 6000-12000 rpm; a time of 3-5 min. In the present disclosure, the shear treatment can not only reduce the particle size of the droplets, but also make the particle size distribution of the droplets more uniform. The droplets of uniform size formed are conducive to reducing the aggregation and collision between the droplets, forming a stable colloidal system.

[0039] In one embodiment of the present disclosure, in step S5, the conditions of the vacuum freeze-drying treatment include pre-freezing treatment, sublimation drying freezing treatment and analytical drying treatment, wherein the temperature of the pre-freezing treatment is (-80)-(-40)°C, and the time is 6-10h; the temperature of the sublimation drying freezing treatment is (-20)-(-10)°C, the time is 20-30h, and the vacuum degree is 30-100Pa; the temperature of the analytical drying treatment is 30-40°C, the time is 6-8h, and the vacuum degree is 30-100Pa.

[0040] In the present disclosure, in step S5, the reduced pressure distillation treatment can adopt the instruments and methods conventionally adopted by those skilled in the art. In order to better remove ethanol, the temperature of the reduced pressure distillation is 40-50°C; and the pressure is 3-5kPa.

[0041] In one embodiment of the present disclosure, in step S6, the mass ratio of the jelly fruit powder to sodium bicarbonate is 1:(0.1-0.3). In the above embodiment, the jelly fruit freeze-dried solid beverage can retain its original sweet and sour taste while ensuring a good re-dissolution effect. The problem of the jelly fruit freeze-dried solid beverage being unable to destroy the microcapsule wall when dissolving due to too little sodium bicarbonate is avoided, and the problem of too much sodium bicarbonate being added to affect the taste and cover up the original sweet and sour taste is effectively avoided.

[0042] In the present disclosure, after vacuum freeze-drying, the jellyfish powder is obtained, wherein the jellyfish freeze-dried solid beverage with low hygroscopicity has a water content of 0-10%.

[0043] The second aspect of the present disclosure provides a freeze-dried solid beverage of Chinese pomelo prepared by the method described in the first aspect.

[0044] The present disclosure is further illustrated below by way of examples, but the present disclosure is not limited thereby.

[0045] In the following examples and comparative examples, unless otherwise specified, the raw materials and reagents used are all commercially available products.

[0046] Unless otherwise specified, the experimental methods used in the following examples and comparative examples are conventional methods.

[0047] In the following examples and comparative examples, the pretreatment step includes: selecting fully mature heart-shaped fruits as raw materials, washing and draining them, and then using a fruit and vegetable crusher (model: ps-0128) to fully crush them.

[0048] Example 1 S1. Place the pre-treated guava in an airbag press (model GSYZ-10) and press at 6 kPa for 2 h to separate the guava juice; S2, placing the obtained chicken heart juice in a freeze concentrator, the freeze concentration conditions are -2°C, the scraper speed is 100 rpm, the stirring speed is 600 rpm, the concentration time is 2 hours, and the volume is reduced to 2 / 3 of the original volume; S3, adding apple pectin (esterification degree of 43%) to the concentrated guava juice at a weight ratio of 100:0.5, and shearing at 6000 rpm for 5 minutes to form a uniform and stable colloidal solution as the first mixture; S4, mixing calcium chloride, zein, ethanol and water in a mass ratio of 0.25:2:30:77.75, stirring at 600 rpm for 10 min; then mixing the obtained mixture with water in a mass ratio of 1:1, and ultrasonically treating at 25° C. and 60 Hz for 20 min to obtain a second mixture; S5, dripping the first mixture dropwise into the second mixture of the same volume, performing vacuum distillation at 45°C and 4Pa to remove ethanol, and then pre-freezing the material after removing ethanol at -40°C for 6 hours; sublimation drying at -20°C and vacuum degree of 40Pa, drying for 24 hours; analytical drying at 30°C and vacuum degree of 40Pa, drying for 8 hours; freeze drying until the moisture content is less than 5%; S6. Mix the guava powder and sodium bicarbonate in a weight ratio of 1:0.2 to obtain a guava freeze-dried solid beverage.

[0049] Example 2 This embodiment adopts the same method as that of Embodiment 1, except that, in step S4, calcium chloride, zein, ethanol and water are mixed in a mass ratio of 0.25:1:30:78.75; the remaining conditions are the same as those of Embodiment 1, and a lyophilized solid beverage of jujube fruit is obtained.

[0050] Example 3 This embodiment adopts the same method as that of embodiment 1, except that, in step S3, the weight ratio of the concentrated pineapple juice to the apple pectin is 100: 1. The remaining conditions are the same as those of embodiment 1, and a pineapple freeze-dried solid beverage is obtained.

[0051] Example 4 This embodiment adopts the same method as that of embodiment 1, except that the volume ratio of the first mixture to the second mixture is 1:2 in step S5. The remaining conditions are the same as those of embodiment 1, and a lyophilized solid beverage of jellyfish is obtained.

[0052] Comparative Example 1 This comparative example adopts the same method as Example 1, except that steps S2, S3 and S4 are not performed. The concentrated fruit juice of the Chinese heart fruit is directly subjected to vacuum freeze-drying treatment. The remaining conditions are the same as those of Example 1, and a Chinese heart fruit freeze-dried solid beverage is obtained.

[0053] Comparative Example 2 This comparative example adopts the same method as Example 1, except that only apple low-ester pectin is added, calcium chloride and zein are not added, and the first mixture is subjected to vacuum freeze-drying. The remaining conditions are the same as those in Example 1, and a lyophilized solid beverage of jelly fruit is obtained.

[0054] Comparative Example 3 This comparative example adopts the same method as Example 1, except that apple low-ester pectin is not added. The remaining conditions are the same as Example 1 to obtain a jelly-dried solid beverage of heart-shaped fruit.

[0055] Comparative Example 4 This comparative example adopts the same method as Example 1, except that in step S3, apple pectin with an esterification degree of 43% is replaced with apple high ester (i.e., high ester pectin) with an esterification degree of 67%. The remaining conditions are the same as those in Example 1, and a lyophilized solid beverage of jelly fruit is obtained.

[0056] Comparative Example 5 This comparative example adopts the same method as Example 1, except that in step S3, the weight ratio of the concentrated pineapple juice to the apple pectin is 100:4; In step S4, the obtained mixed material is mixed with water at a mass ratio of 1:0.5 and subjected to ultrasonic treatment to obtain a second mixture.

[0057] The remaining conditions were the same as those in Example 1 to obtain a lyophilized solid beverage of jellyfish.

[0058] Comparative Example 6 This comparative example adopts the same method as Example 1, except that the second mixture is replaced with a 0.5% zein solution by mass fraction. The remaining conditions are the same as those in Example 1, and a lyophilized solid beverage of jellyfish is obtained.

[0059] Test Case The following tests were performed on the lyophilized solid beverages of the embodiment and the comparative example: Moisture content: Determined using the method specified in the national standard GB / T8858-1988 "Determination of dry matter and moisture content in fruit and vegetable products". Figure 1 shown.

[0060] Determination of moisture absorption rate: Dry the weighing bottle to constant weight, recorded as M 0 , spread 2-3g of freeze-dried powder and weigh it (the same weight as the freeze-dried block), record it as M, place the weighing bottle in a constant temperature and humidity environment for balance, weigh it every 5 days, and record the mass after moisture absorption as M 1 , M 2 , M 3 ……M n , t is the storage time, and the moisture absorption rate is calculated according to the following formula. The result is as follows Figure 2 shown.

[0061]

[0062] Contact angle measurement: Weigh a small amount of freeze-dried powder, and then use a tablet press to process the sample into a disc with a thickness of 2 mm and a diameter of 13 mm. Put the obtained particle piece in a glass dish filled with peanut oil and place it on the stage. Gently drip water into it through a high-precision syringe, pay attention to emptying the bubbles in the syringe, and take pictures after stabilization. Use SCA20 software to automatically fit the profile data of the droplet and calculate the contact angle of the sample. The results are shown in Table 1.

[0063] Low-field NMR relaxation time determination: Weigh 0.2 g of the sample to be tested and wrap it in polytetrafluoroethylene to prevent water from evaporating during the test. Place it in a nuclear magnetic tube and then put it into the probe coil for detection at a temperature of 30°C. Perform a scanning experiment with the following detection settings: proton resonance frequency of 21 MHz, spectral width of 100 kHz, repetition interval of 3000 ms, repeated scans of 16 times, relaxation decay time of 0.16 ms, and echo number of 4000. Each sample was subjected to three repeated experiments and the average value was taken. The transverse relaxation time (T 2 ) attenuation curve is inverted to obtain the sample’s T 2 The results are as follows Figure 3 shown.

[0064] Table 1

[0065] Depend on Figure 1 It can be seen that the water content of the lyophilized solid beverage of the Chinese heart fruit increases with the extension of storage time. The water content of the lyophilized solid beverage of the Chinese heart fruit of Examples 1-4 is lower than that of Comparative Examples 1-4; especially the lyophilized solid beverage of the Chinese heart fruit prepared in Examples 2 and 3, indicating that the lyophilized solid beverage of the Chinese heart fruit prepared by the method disclosed in the present invention has a good anti-hygroscopic effect.

[0066] Depend on Figure 2 It can be seen that the moisture absorption rate will change with the change of water content in the lyophilized solid beverage of the Chinese heart fruit and its characteristics. As the storage time increases, the water content in the sample gradually increases and the moisture absorption rate gradually decreases. The moisture absorption rate of the lyophilized solid beverage of the Chinese heart fruit of Examples 1-4 is lower than that of Comparative Examples 1-4, indicating that the lyophilized solid beverage of the Chinese heart fruit prepared by the method disclosed in the present invention has a good anti-hygroscopic effect. In particular, Example 2 has better hydrophobicity than other groups, and its moisture absorption rate is also slower than other groups.

[0067] Depend on Figure 3 It can be seen that the transverse relaxation times corresponding to the three states of water are bound water T 21 (peak time <10ms), not easy to flow water T 22(10 ms < peak time < 100 ms) and free water T 23 (Peak time>100ms). T 2 The relaxation time reflects the degree of binding between water and substances. The shorter the time, the tighter the binding and the smaller the fluidity. Figure 3 It can be seen that as the storage time increases, the water absorption of the freeze-dried powder increases, and the content of free water molecules is higher. It can be clearly seen that the water distribution of Example 2 changes less than that of Comparative Example 1.

[0068] As shown in Table 1, the pure chicken heart juice freeze-dried powder prepared in Comparative Example 1 has a high hydrophilicity (contact angle <30°), the addition of low-ester pectin alone in Comparative Example 2 and the absence of apple low-ester pectin in Comparative Example 3 cannot effectively improve the hydrophobicity of the freeze-dried powder, while when zein nanoparticles, Ca 2+ When added with low-ester pectin, the three will form a complex to improve the hydrophobicity of the freeze-dried powder. 2+ The effect of adding low-ester pectin on improving the hydrophobicity of freeze-dried powder is also different. In Comparative Example 4, because the high-ester pectin has a small charge, the combination of the three is not stable, and the improvement of the hydrophobicity of the freeze-dried powder is limited. When too much low-ester pectin is added (Comparative Example 5) and zein is added alone (Comparative Example 6), although the hydrophobicity of the freeze-dried powder is effectively improved, the dispersion effect during reconstitution becomes worse, which is contrary to the product development concept.

[0069] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0070] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0071] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A method for preparing a freeze-dried solid beverage of jellyfish with low hygroscopicity, characterized in that: The steps include: S1, subjecting the pretreated sago palm to a squeezing and separation process to obtain sago palm juice; S2, subjecting the jackfruit juice to freeze concentration treatment to obtain jackfruit concentrated juice; S3, mixing the pineapple concentrated juice and low-ester pectin and performing shearing treatment to obtain a first mixture; S4, mixing calcium chloride, zein, ethanol and water to obtain a second mixture; S5, spraying the first mixture into the second mixture, subjecting the obtained third mixture to vacuum distillation to remove ethanol and then to vacuum freeze-drying to obtain guava powder; S6. Mixing the jackfruit powder with sodium bicarbonate to obtain a jackfruit freeze-dried solid beverage.

2. The method according to claim 1, wherein: In step S3, the weight ratio of the concentrated pineapple juice to the low-ester pectin is 100: (0.1-1.0); The esterification degree of the low-ester pectin is 40-50%; the low-ester pectin is selected from one or more of citrus pectin, apple pectin and sunflower pectin.

3. The method according to claim 2, wherein: In step S5, the volume ratio of the first mixture to the second mixture is 1:(1-2).

4. The method according to claim 1, wherein: In step S4, the second mixture is prepared by the following method: SS1, mixing calcium chloride, zein, ethanol and water and stirring to obtain a mixed material; SS2. Mixing the mixture with water and then subjecting the mixture to ultrasonic treatment to obtain the second mixture.

5. The method according to claim 4, wherein: In step SS1, the mass ratio of calcium chloride, zein, ethanol and water is 0.25:(1-2):(30-40):(50-80); The stirring conditions include: a rotation speed of 400-600 rpm and a time of 5-10 min; In step SS2, the mass ratio of the mixed material to water is 1:(1-3); The conditions of the ultrasonic treatment include: temperature of 25-30°C, frequency of 40-60 Hz, and time of 20-30 min.

6. The method according to claim 1, wherein: In step S1, the pretreatment includes: selecting fully mature pineapple, washing, draining, and then crushing.

7. The method according to claim 1, wherein: In step S1, the conditions of the squeezing separation treatment include: a pressure of 5-7 kPa and a time of 1-2 h; In step S2, the freeze concentration treatment conditions include: temperature of (-1)-(-3)°C, scraper speed of 80-100 rpm, stirring speed of the stirrer of 400-600 rpm, concentration time of 1-2 hours; the volume of the concentrated pineapple juice is 1 / 3-2 / 3 of the pineapple juice; In step S3, the shearing treatment conditions include: a shearing speed of 6000-12000 rpm; a time of 3-5 min; In step S5, the conditions of the vacuum freeze-drying treatment include pre-freezing treatment, sublimation drying freezing treatment and analytical drying treatment, wherein the temperature of the pre-freezing treatment is (-80)-(-40)°C, and the time is 6-10h; the temperature of the sublimation drying freezing treatment is (-20)-(-10)°C, the time is 20-30h, and the vacuum degree is 30-100Pa; the temperature of the analytical drying treatment is 30-40°C, the time is 6-8h, and the vacuum degree is 30-100Pa.

8. The method according to claim 1, wherein: In step S6, the mass ratio of the pineapple powder to sodium bicarbonate is 1:(0.1-0.3).

9. The method according to claim 1, wherein: The water content of the jelly-dried solid beverage of jellyfish is 0-10%.

10. A freeze-dried solid beverage of jellyfish prepared by the method according to any one of claims 1 to 9.

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