CN113575802A

CN113575802A - Candy reducing juice and preparation method thereof

Info

Publication number: CN113575802A
Application number: CN202110854403.2A
Authority: CN
Inventors: 俞伟祖; 宋景深
Original assignee: Liangpin Puzi Nutritional Food Co ltd
Current assignee: Liangpin Puzi Nutritional Food Co ltd
Priority date: 2021-07-28
Filing date: 2021-07-28
Publication date: 2021-11-02

Abstract

The invention is suitable for the technical field of food processing, and provides a sugar-reducing candy juice and a preparation method thereof, wherein the sugar-reducing candy juice comprises the following steps: unfreezing the frozen squeezed juice ice blocks; primarily filtering the unfrozen fruit juice; ultra-filtering the filtered juice to remove solids; performing nanofiltration and sugar reduction treatment on the juice subjected to ultrafiltration and solid removal; sterilizing and packaging the juice subjected to nanofiltration and sugar reduction treatment. The natural juice is used as a main raw material, sugar reduction is carried out by a physical membrane filtration method, and part of glucose, fructose, cane sugar and other sugars in the processed juice are removed, so that the calorific value of the natural juice is reduced, and the natural beverage conforming to the development trend of the beverage is prepared, and is beneficial to the health of consumers.

Description

Candy reducing juice and preparation method thereof

Technical Field

The invention belongs to the technical field of food processing, and particularly relates to a sugar-reducing candy juice and a preparation method thereof.

Background

The fruit juice is prepared from fruits by physical method such as squeezing, centrifuging, and extracting to obtain juice product, and processing to obtain various fruit juice beverages. The fruit juice retains most of the nutrients in the fruit, such as vitamins, minerals, sugar, pectin in dietary fiber, etc. The juice can help digestion, moisten intestines and supplement the deficiency of nutrient components in the diet if being drunk frequently. According to the health diet standard newly advocated by the World Health Organization (WHO): "at least 400 grams (5 parts) of fruits and vegetables are consumed per day". The standard is difficult to achieve by only depending on the supplement of the vegetables and the fruits of three meals a day, and the standard can be achieved to a great extent if the vegetables and the fruits of three meals a day are taken together with the fruit and vegetable juice beverage. Advocating dietary diversity will increase the demand for fruit and vegetable juices. In recent years, due to the shift in consumption concept, many consumers have abandoned carbonated beverages that provide little to no nutrients to the body, moving to healthier juice beverages or water or functional beverages. The change of the consumption intention of the consumers on the beverage products influences the production scale, the market promotion and maintenance, and the research and development of new products of the beverage manufacturing enterprises to a certain extent.

The fruit generally contains 10-12% of sugar, the high sugar content in the fruit brings great consumption pressure to consumers, and excessive intake of the fruit easily causes the sugar content to be converted into fat to form fat accumulation.

Disclosure of Invention

In view of the above problems, the present invention aims to provide a reduced-sugar juice and a preparation method thereof, and aims to solve the technical problems that the existing fruit juice beverage has high sugar content and is not good for the health of consumers.

In one aspect, the method of making reduced sugar juice comprises the steps of:

step S1, unfreezing the frozen squeezed juice ice blocks;

step S2, primary filtering the unfrozen fruit juice;

step S3, ultra-filtering solid treatment is carried out on the filtered juice;

step S4, performing nanofiltration and sugar reduction treatment on the ultra-filtered and solid fruit juice;

and step S5, sterilizing and packaging the juice subjected to nanofiltration and sugar reduction treatment.

Further, the step S1 specifically includes: putting the frozen squeezed juice ice blocks into negative pressure equipment for unfreezing, and controlling the pressure to be-0.02 to-0.05 MPa.

Further, the step S2 specifically includes:

filtering the fruit juice by using vacuum filtration equipment, specifically, putting a 100-mesh filter bag into a filter cylinder of the stainless steel vacuum filtration equipment, then fixing, putting the unfrozen fruit juice into the filter bag, carrying out suction filtration at room temperature, controlling the pressure in the filtration process to be-0.03-0.1 MPa, and leaving no precipitated fruit particles and other physical foreign matters after filtration.

Further, the step S3 specifically includes:

and (3) transferring the ultrafiltration membrane core with the aperture of 30-100 nm into membrane operation equipment, performing ultrafiltration solid removal treatment at room temperature, controlling the pressure to be 0.5-2 MPa in the treatment process, and starting cooling circulating water to control the temperature of the juice material to be lower than 25 ℃ when the temperature of the juice material rises to be higher than 25 ℃ because of pressure rise.

Further, the step S4 specifically includes:

pouring the ultra-filtered and solid-removed juice into a circulating tank of nanofiltration equipment, wherein the nanofiltration equipment is filled with a nanofiltration membrane core with the aperture of 1-10nm, starting the filtration operation at room temperature, and controlling the concentration of the circulating juice to be 6-18% and the operating pressure to be 1.5-3.5 MPa in the nanofiltration and sugar reduction process.

Furthermore, the concentration of the circulating fruit juice is controlled to be 8-12% in the nanofiltration sugar reduction process, the operating pressure is 1.5-2.5 Mpa, the temperature of the fruit juice material is controlled to be lower than 25 ℃ in the circulating process, and when the temperature exceeds the temperature, the cooling circulating water is started to cool.

And further, cleaning nanofiltration equipment by using edible caustic soda within 1 hour after nanofiltration sugar reduction treatment is finished, and soaking the nanofiltration membrane core by using 0.5-2% sodium nitrite solution until the nanofiltration membrane core is washed by water before use if the nanofiltration equipment is not used for a long time.

Further, the step S5 specifically includes:

the method comprises the steps of filling the fruit juice subjected to nanofiltration and sugar reduction treatment in a packaging bottle, conveying the fruit juice by a conveying belt, and sterilizing the fruit juice by a sterilization kettle in a spray type sterilization mode, wherein the temperature is controlled to be higher than 121 ℃ in the sterilization process, and the passing time is controlled to be 10-20 s.

In another aspect, the reduced candy juice is prepared by the above preparation method.

The invention has the beneficial effects that: the invention relates to a physical sugar-reducing processing technology, which is used for reducing monosaccharide and disaccharide in fruit juice, separating micromolecular sugar from the fruit juice to properly reduce the sweetness of the fruit juice, but not changing all other tastes and components, and successfully reducing the sugar content of the fruit juice by 30-50%.

Drawings

FIG. 1 is a flow chart of a method for preparing reduced-sugar juice provided by the present invention;

FIG. 2 is a graph showing the results of sugar detection of a fruit juice sample before nanofiltration sugar reduction treatment according to the first embodiment of the present invention;

FIG. 3 is a graph showing the results of sugar detection of a juice sample after nanofiltration sugar reduction treatment according to the first embodiment of the present invention;

FIG. 4 is a graph showing the results of sugar detection of a sample of fruit juice before nanofiltration sugar reduction treatment according to a second embodiment of the present invention;

FIG. 5 is a graph showing the results of sugar detection of a juice sample after nanofiltration sugar reduction treatment according to a second embodiment of the present invention;

FIG. 6 is a graph showing the results of sugar detection of a sample of fruit juice before nanofiltration sugar reduction treatment according to a third embodiment of the present invention;

fig. 7 is a graph showing the result of sugar detection of a juice sample after nanofiltration sugar reduction treatment in the third example of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1, the method for preparing sugar-reduced fruit juice provided by the invention comprises the following steps:

and a step S1 of thawing the frozen pressed juice ice cubes.

The fruit juice is prepared by adopting a pure natural fruit fresh squeezing technology without adding any preservative or ingredient, the fruit juice is squeezed into juice and then stored under a freezing condition below 18 ℃ below zero, the transportation process is also carried out through a cold chain, and the temperature fluctuation is controlled within 2 ℃. Fruit juice types include, but are not limited to, grape juice, mango juice, orange juice, pear juice. The juice after arrival needs to be subjected to a thawing treatment before the membrane treatment.

The natural thawing method can be generally adopted, the unopened and sealed fruit juice is placed in a shady and cool place for thawing at room temperature, but the room temperature is controlled not to exceed 30 ℃, and the fruit juice is placed for 3 to 8 hours until ice cubes are completely dissolved.

During natural thawing, ice crystals are thawed along with phase change in the thawing process of ice cubes, the original structure of the juice can be influenced, and the taste and flavor of the juice product can be influenced, so that frozen pressed juice ice cubes are preferably placed in a negative pressure device to be thawed, and the pressure is controlled to be-0.02 to-0.05 MPa.

Step S2 is a preliminary filtration process of the thawed juice.

A large amount of precipitated fruit grains or physical foreign matters brought by the outside are also arranged in the unfrozen fruit juice raw material, and the fruit juice is filtered by using vacuum filtration equipment according to different fruit juice types needing to be treated. Specifically, a 100-mesh filter bag with 400 meshes is placed into a filter cylinder of stainless steel vacuum filtration equipment and then fixed, unfrozen fruit juice is placed into the filter bag for filtration at room temperature, the pressure is controlled to be-0.03 to-0.1 MPa in the filtration process, and no precipitated fruit particles and other physical foreign matter residues are left after filtration.

And step S3, performing ultra-filtration fixation treatment on the filtered juice.

The fruit juice that removes the edulcoration through the filter bag and removes solid the processing still has more suspension form fruit grain and be colloidal substance in, if directly use the less nanofiltration membrane of aperture to subtract sugar processing, take place to block up the membrane phenomenon of stepping up very easily, so need receive the filtration solid processing before carrying out the processing of subtracting sugar.

Specifically, an ultrafiltration membrane core with the aperture of 30-100 nm is transferred into membrane operation equipment, ultrafiltration solid removal treatment is carried out at room temperature, the pressure is controlled to be 0.5-2 MPa in the treatment process, and when the temperature of the fruit juice material rises to be higher than 25 ℃ due to the rise of the pressure, cooling circulating water is started to control the temperature of the fruit juice material to be lower than 25 ℃.

And step S4, performing nanofiltration and sugar reduction treatment on the juice subjected to ultrafiltration and solid removal.

By combining the filtration efficiency and considering prolonging the service life of the nanofiltration membrane, the concentration of the circulating juice is controlled to be 8-12% in the nanofiltration sugar reduction process, and the operating pressure is 1.5-2.5 MPa. The concentration of the fruit juice is controlled by circularly concentrating and adding purified water, and the concentration is sampled and detected once every half hour for monitoring; the temperature of the fruit juice material is controlled to be lower than 25 ℃ in the circulating process, and when the temperature exceeds the temperature, the cooling circulating water is started to cool.

In addition, edible caustic soda is used for cleaning nanofiltration equipment within 1 hour after nanofiltration sugar reduction treatment is finished, and if the nanofiltration equipment is not used for a long time, 0.5-2% of sodium hydrogen nitrite solution is used for soaking the nanofiltration membrane core until the nanofiltration membrane core is washed by water before use, so that the service life of the membrane can be prolonged.

The fruit juice subjected to nanofiltration and sugar reduction treatment is filled in a packaging bottle (such as a 220-.

And (4) sampling the sterilized juice to carry out microbial detection verification, wherein the detection result can meet the relevant standard requirements. The fruit juice subjected to ultrahigh-temperature instantaneous sterilization is placed in a rubble carton for packaging and then is placed in a cool warehouse for storage.

The invention adopts the membrane technology to process the fruit juice, and the membrane processing has no phase change, thereby greatly reducing the risk of food denaturation and also obviously reducing the energy consumption in the phase change process; after solid matters and impurities in the juice are removed by adopting an ultrafiltration membrane technology, monosaccharide and disaccharide in the clarified juice are removed by adopting a nanofiltration membrane, and the nanofiltration membrane can intercept and remove single-valence ions and organic matters with molecular weight lower than 200, so that the isolation or purification effect can be effectively achieved; in addition, the technical equipment occupies a small area compared with other separation and concentration equipment, and is convenient to install and use.

The following examples are specifically given.

The first embodiment is as follows:

thawing grape juice, filtering the grape juice by using a filter bag with 200 meshes, and filtering at room temperature without precipitate fruit grains and other physical foreign matter residues; and (3) carrying out ultrafiltration solid removal treatment on the filtered grape juice at room temperature, wherein the pore size of an ultrafiltration membrane core is 60nm, the control pressure of the operation process is 1.2MPa, the operation time is 3.5h, and when the temperature of the material rises to be higher than 25 ℃ due to the rise of the pressure, cooling circulating water is started to control the temperature of the grape juice material to be lower than 25 ℃.

And (4) feeding the grape juice subjected to ultra-filtration solid removal treatment to perform sugar content detection.

Pouring 40L of grape juice subjected to ultrafiltration and solid removal treatment into a circulating tank of a nanofiltration device, loading a membrane core with the pore size of 7nm into the nanofiltration device, starting filtration operation at room temperature, controlling the concentration of the circulating juice to be 10% in the nanofiltration and sugar reduction process, and controlling the operating pressure to be 2.0 MPa; the concentration of the fruit juice is controlled by circularly concentrating and adding purified water, and the concentration is sampled and detected once every half hour for monitoring; the temperature of the fruit juice material is controlled to be lower than 25 ℃ in the circulating process, and when the temperature exceeds the temperature, the cooling circulating water is started to cool. And carrying out nanofiltration and sugar reduction to obtain 16.6L of grape juice.

And finally, conveying the filtered and sugar-reduced grape juice to a sample for sugar detection.

Comparing the sugar content of the grape juice before and after treatment, observing the sugar reducing effect, and the results of the two sugar detection are respectively shown in fig. 2 and 3. The concentration times of the grape juice after treatment are combined for calculation, and the total sugar can be reduced by 56% after membrane treatment.

Example two:

thawing apple juice, filtering the apple juice by using a filter bag of 250 meshes, and filtering at room temperature without precipitate fruit grains and other physical foreign matter residues; and (3) performing ultrafiltration solid removal treatment on the filtered apple juice at room temperature, wherein the pore size of an ultrafiltration membrane core is 70nm, the pressure is controlled to be 1.0MPa in the operation process, the operation time is 3h, and when the temperature of the material rises to be higher than 25 ℃ due to the rise of the pressure, cooling circulating water is started to control the temperature of the apple juice material to be lower than 25 ℃.

And (4) feeding the apple juice subjected to ultra-filtration solid removal treatment into a sample to perform sugar detection.

Pouring 40L of the apple juice subjected to ultrafiltration and solid removal treatment into a circulating tank of a nanofiltration device, loading a membrane core with the pore size of 5nm into the nanofiltration device, starting filtration operation at room temperature, controlling the concentration of the circulating fruit juice to be 12% in the nanofiltration and sugar reduction process, and controlling the operating pressure to be 2.5 MPa; the concentration of the fruit juice is controlled by circularly concentrating and adding purified water, and the concentration is sampled and detected once every half hour for monitoring; the temperature of the fruit juice material is controlled to be lower than 25 ℃ in the circulating process, and when the temperature exceeds the temperature, the cooling circulating water is started to cool. Nanofiltration and sugar reduction are carried out to obtain 17.5L of apple juice.

And finally, conveying the apple juice subjected to nanofiltration and sugar reduction to a sample for sugar detection.

Comparing the sugar content of the apple juice before and after the treatment, observing the sugar reducing effect, wherein the results of the two sugar detection are respectively shown in fig. 4 and 5. By combining the calculation of the concentration times of the apple juice after treatment, 48 percent of total sugar can be reduced after membrane treatment.

Example three:

thawing orange juice, filtering the juice by using a 300-mesh filter bag, wherein the filtering process is carried out at room temperature, and no precipitate fruit grains and other physical foreign matter residues are left after filtering; and (3) performing ultrafiltration solid removal treatment on the filtered orange juice at room temperature, wherein the pore size of an ultrafiltration membrane core is 60nm, the pressure is controlled to be 1.0MPa in the operation process, the operation time is 3.5h, and when the temperature of the material rises to be higher than 25 ℃ due to the rise of the pressure, cooling circulating water is started to control the temperature of the apple juice material to be lower than 25 ℃.

And (5) feeding the orange juice subjected to ultra-filtration solid removal treatment to perform sugar content detection.

Pouring 40L of the orange juice subjected to ultrafiltration and solid removal treatment into a circulating tank of nanofiltration equipment, loading membrane cores with the pore size of 5nm into the nanofiltration equipment, starting filtration operation at room temperature, controlling the concentration of the circulating juice to be 10% in the nanofiltration and sugar reduction process, and controlling the operating pressure to be 2.2 MPa; the concentration of the fruit juice is controlled by circularly concentrating and adding purified water, and the concentration is sampled and detected once every half hour for monitoring; the temperature of the fruit juice material is controlled to be lower than 25 ℃ in the circulating process, and when the temperature exceeds the temperature, the cooling circulating water is started to cool. Nanofiltration is carried out to reduce sugar to obtain 15.5L of apple juice.

And finally, the orange juice subjected to nanofiltration and sugar reduction is sent to a sample for sugar detection.

Comparing the sugar content of the orange juice before and after the treatment, the sugar reducing effect is observed, and the results of the two sugar tests are respectively shown in fig. 6 and 7. The membrane treatment was found to reduce 58% of the total sugar content, calculated in combination with the concentration factor of the orange juice after treatment.

In conclusion, the natural fruit juice is used as a main raw material, sugar is reduced by a physical membrane filtration method, and part of glucose, fructose, cane sugar and other sugars in the processed fruit juice are removed, so that the calorific value of the natural fruit juice is reduced, and the natural fruit juice is prepared into a natural beverage meeting the development trend of the beverage.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A method for preparing sugar-reduced fruit juice, which is characterized by comprising the following steps:

step S1, unfreezing the frozen squeezed juice ice blocks;

step S2, primary filtering the unfrozen fruit juice;

step S3, ultra-filtering solid treatment is carried out on the filtered juice;

2. The method for preparing sugar-reduced fruit juice according to claim 1, wherein the step S1 specifically comprises:

putting the frozen squeezed juice ice blocks into negative pressure equipment for unfreezing, and controlling the pressure to be-0.02 to-0.05 MPa.

3. The method for preparing sugar-reduced fruit juice according to claim 1, wherein the step S2 specifically comprises:

4. The method for preparing sugar-reduced fruit juice according to claim 1, wherein the step S3 specifically comprises:

5. The method for preparing sugar-reduced fruit juice according to claim 1, wherein the step S4 specifically comprises:

6. The method for preparing sugar-reducing fruit juice according to claim 5, wherein the concentration of the circulating fruit juice is controlled to be 8-12% in the nanofiltration sugar-reducing process, the operating pressure is 1.5-2.5 Mpa, the temperature of the fruit juice material is controlled to be lower than 25 ℃ in the circulating process, and when the temperature exceeds the temperature, the cooling circulating water is started to cool.

7. The method for preparing sugar-reduced fruit juice according to claim 6, wherein the nanofiltration equipment is cleaned with edible caustic soda within 1 hour after the nanofiltration sugar reduction treatment is completed, and if the nanofiltration equipment is not used for a long time, the nanofiltration membrane core is soaked with 0.5-2% sodium nitrite solution until the nanofiltration membrane core is washed with water before use.

8. The method for preparing sugar-reduced fruit juice according to claim 1, wherein the step S5 specifically comprises:

9. A reduced-sugar fruit juice, wherein said reduced-sugar fruit juice is produced by the method of any one of claims 1 to 8.