Disclosure of Invention
The method aims to solve the problems that in the prior art, during the process of milling blueberry fruits, the material rises by mechanical processing to destroy heat-sensitive components, and the prepared blueberry powder contains a large amount of cellulose, cannot be brewed and has poor taste.
In one or more embodiments of the present disclosure, a blueberry powder processing method is provided, which includes the steps of processing under a full low temperature condition, crushing fresh blueberries, separating dregs from slurry, freezing the slurry, and dicing to obtain the blueberry powder;
the processing under the full low temperature condition means that intermediate products from fresh blueberries to blueberry fruit powder are stored and transported at the temperature of-20-5 ℃ among specific processing technologies.
In one or more embodiments of the disclosure, blueberry fruit powder prepared by the blueberry fruit powder processing method is provided.
In one or more embodiments of the disclosure, an application of the blueberry fruit powder in anthocyanin extraction is provided.
In one or more embodiments of the disclosure, an application of the blueberry fruit powder in preparation of an anti-scurvy drug or health product is provided.
One or some of the above technical solutions have the following advantages or beneficial effects:
1) the method is based on a quality-grading processing principle, separates a water-insoluble cellulose component from a water-soluble pulp, processes the pulp, and carries out quality-grading processing according to nutritional ingredients and heat-sensitive characteristics in fruits and vegetables. Adopts a full low-temperature treatment process to preserve heat-sensitive functional components to the maximum extent. The prepared blueberry fruit powder can be completely dissolved in water, has the advantages of good instant solubility and good taste without sediment, and is suitable for processing food or directly preparing into granules.
2) The blueberry fruit powder prepared by the method greatly retains thermosensitive components mainly comprising anthocyanin and vitamin c, and the method is proved by experiments that less thermosensitive components are decomposed on the premise of not adding protective agents such as phytosterol and the like, so that the protective agents can be saved, the blueberry fruit powder is single in component, and the mouth feel is good.
3) The temperature is strictly controlled to be the full low temperature mainly in the process of processing the blueberry powder, other indexes are not required to be strictly controlled, the requirement on operators is low, and the operation is simple and easy to control. The adoption of low-temperature crushing avoids the problem that the temperature of the material is increased due to the action of mechanical shearing force in the direct pulping process, and the temperature of the material is reduced to 0-5 ℃ even in the direct pulping process, the pulping of the crusher still generates local high temperature to destroy heat-sensitive components such as anthocyanin, Vc and the like in the blueberries.
Detailed Description
The technical solutions in the embodiments of the present disclosure will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the disclosure without making any creative effort, shall fall within the protection scope of the disclosure.
The method aims to solve the problems that in the prior art, during the process of milling blueberry fruits, the material rises by mechanical processing to destroy heat-sensitive components, and the prepared blueberry powder contains a large amount of cellulose and pectin, is poor in water solubility, cannot be brewed and is poor in taste.
In one or more embodiments of the present disclosure, a method for processing blueberry fruit powder is provided, which includes the steps of processing under a full low temperature condition, crushing fresh blueberries, separating dregs from slurry, freeze-drying the slurry, and cutting into particles;
the processing under the full low temperature condition means that intermediate products from fresh blueberries to blueberry fruit powder are stored and processed at the temperature of-20-5 ℃ between specific processing technologies.
The disclosed full low temperature processing cooperates with single component processing to avoid decomposition of heat sensitive components.
Based on the quality grading processing principle, the insoluble cellulose component is separated from the pulp, the pulp is processed, and quality grading processing is carried out according to the nutritional ingredients and the heat-sensitive characteristic in the fruits and vegetables. Adopts a full low-temperature treatment process to preserve heat-sensitive functional components to the maximum extent. The prepared blueberry fruit powder can be completely dissolved in water, and is suitable for processing food or directly preparing into granules.
Preferably, the raw material used in the blueberry fruit powder processing method is only fresh blueberries.
Preferably, the crushing method specifically adopts wet-process low-temperature (-20 to-15 ℃) ultrafine crushing or low-temperature crushing after quick freezing; crushing at this temperature generates less heat and does not decompose heat sensitive components in the material.
Preferably, the specific steps of crushing at low temperature after quick freezing comprise quick freezing at-40 ℃, and then crushing at-20 to-15 ℃ for 2 to 5 minutes.
Preferably, the method for separating the dregs from the slurry is filtration, and the filtration temperature is below 0 ℃, until solid insoluble substances can not be seen by naked eyes;
preferably, a suction filtration mode is adopted for processing, and in the suction filtration process, the blueberry intermediate product and the glass beads are placed in a container; further preferably, the blueberry pulp is melted before the suction filtration, and the temperature is controlled to be about 0 ℃.
Preferably, spray freezing granulation (below 5 ℃) is carried out before freeze drying, and then dehydration is finished by adopting a normal pressure freeze drying process to prepare dry powder; or directly adopting normal pressure quick freeze drying process, drying and blocking.
Preferably, the freeze drying further comprises a freeze concentration process; it is noted that only one of concentration and spray granulation is required.
Preferably, the temperature of the freezing concentration process is 0 to-5 ℃;
preferably, the freeze concentration process removes 30-80% of water (the sugar degree is concentrated from 10BX to 45BX at most).
Preferably, the temperature of the massive material formed by direct freeze drying and re-granulating is below 5 ℃;
in one or more embodiments of the disclosure, blueberry fruit powder prepared by the blueberry fruit powder processing method is provided.
In one or more embodiments of the disclosure, an application of the blueberry fruit powder in anthocyanin extraction is provided.
In one or more embodiments of the disclosure, an application of the blueberry fruit powder in preparation of an anti-scurvy drug or health product is provided.
Blueberry fruit powder processing
Example 1
The embodiment provides a processing method of blueberry fruit powder, which comprises the following steps,
1) cleaning blueberries with water, placing the washed blueberries and draining, standing the drained blueberries for 3 hours at a low temperature, and crushing the blueberries, wherein the crushing mode is low-temperature crushing, namely quick freezing at the temperature of-40 ℃ and then crushing at the temperature of-20-15 ℃;
2) slowly heating the crushed blueberries to about 0 ℃ to melt the soluble substances, then separating dregs from the pulp by using gauze filtration, and discarding the dregs; filtering for several times until solid insoluble substances can not be seen by naked eyes;
3) atomizing the slurry at the temperature of 5 ℃ into cold air at the temperature of-40 ℃ for spray freezing granulation, and then carrying out normal pressure freeze drying at the temperature of-20-0 ℃ to obtain blueberry dry powder;
4) and sterilizing the frozen dry powder by adopting ultraviolet rays to obtain the high-quality blueberry powder.
The steps 1) to 4) are processed under the condition of full low temperature.
Example 2
The embodiment provides a processing method of blueberry fruit powder, which comprises the following steps,
1) cleaning blueberries with water, placing and draining, standing the drained blueberries for 3 hours at a low temperature, and crushing the blueberries, wherein the crushing mode is low-temperature superfine crushing, and the temperature of blueberry materials is controlled below-15 ℃ during crushing;
2) the temperature of the slurry is about 0 ℃, dregs and the slurry are separated by using a suction filtration method, and during the suction filtration process, the blueberry intermediate product and glass beads are placed in a container, and only the slurry is reserved;
3) carrying out normal-pressure spray freezing granulation on the slurry at the temperature of between 0 and 4 ℃ below zero, increasing the sugar degree from 10BX to 14 to 16BX, and then carrying out freeze drying;
4) freeze-drying the slurry;
5) and (4) sterilizing by adopting ozone to obtain blueberry powder particles.
The steps 1) to 4) are processed under the condition of full low temperature.
Example 3
The embodiment provides a processing method of blueberry fruit powder, which comprises the following steps,
1) cleaning blueberries with water, placing the cleaned blueberries, draining the water, placing the drained blueberries at a low temperature of 5 ℃ for standing for 3 hours, and crushing the blueberries, wherein the crushing mode is mashing, and the temperature of materials is controlled not to exceed 5 ℃ in the crushing process;
2) filtering at 5 deg.C with gauze to separate residue from slurry, and discarding residue; filtering for several times until solid insoluble substances can not be seen by naked eyes;
3) freezing and concentrating the slurry at 0-5 ℃ to remove 70-80% of water, increasing the sugar degree from 10BX to 45BX, and then freezing and drying;
4) and (3) cutting the frozen block-shaped blueberry material into particles at the temperature of-5-0 ℃, and sterilizing by adopting gamma rays to obtain blueberry powder particles.
The steps 1) to 4) are processed under the condition of full low temperature.
Comparative example 1
This example provides a method for processing blueberry powder, which is different from example 1 in that there is no filtering step (step 2)), that is, the blueberry is not processed according to quality, and then vacuum freeze-drying is adopted.
Comparative example 2
The embodiment provides a processing method of blueberry powder, which is different from the embodiment 1 in that in the step 1), blueberries are frozen at a temperature of between 40 ℃ below zero and 20 ℃ below zero and then are crushed at normal temperature.
Comparative example 3
The embodiment provides a processing method of blueberry powder, which is different from the embodiment 1 in the steps 1) and 3), the blueberry is frozen at the temperature of-40 to-20 ℃, then crushed at normal temperature, campesterol is added as a protective agent, and then vacuum freeze drying is adopted.
Component content test
1. Measurement of anthocyanin content
The chemical property of the anthocyanin determines the stable property of the anthocyanin under the weak acidic condition, so that a weak acidic alcoholic solution or aqueous solution is more applied to the extraction of the anthocyanin. The test adopts ultrasonic extraction and high performance liquid chromatography for determination.
The method for determining the total anthocyanin of the blueberries comprises the following steps: respectively weighing 0.6g of 6 groups of blueberry fruit powder in examples 1-3 and comparative examples 1-3, adding 50mL of 3% methanolic acid solution by mass, uniformly mixing, fixing the volume to 500mL, and performing ultrasonic extraction for 30 min. And (4) detecting the solution by using a high performance liquid chromatograph, and calculating the anthocyanin content according to the peak area.
The anthocyanin is also called anthocyanidin, belongs to flavonoid compounds, is one of important functional substances of blueberries, and is tested by a high performance liquid chromatography method to respectively determine the content of the total anthocyanin in 6 groups of blueberry fruit powder. The total anthocyanin content of 6 groups of blueberry powder is shown in table 1.
TABLE 1
Serial number
|
Total anthocyanidin content/(mg/mL)
|
Example 1
|
6.70
|
Example 2
|
6.74
|
Example 3
|
6.52
|
Comparative example 1
|
5.22
|
Comparative example 2
|
4.34
|
Comparative example 3
|
5.37 |
As can be seen from table 1, the method of comparative example 1, in which the fractionation process was not performed, resulted in a lower anthocyanin content, whereas in comparative example 2, the anthocyanin content was greatly reduced by crushing at normal temperature, and it is apparent that the crushing at normal temperature causes a large amount of pyrolysis of anthocyanin. When campesterol was added as a protective agent in comparative example 3, although the anthocyanins protected part of the anthocyanins from pyrolysis, from table 1 the anthocyanins content in comparative example 3 remained much lower than in example 1, and it is clear that even with the addition of a protective agent, it is not possible to replace the all low temperature processing.
2. Testing for vitamin C content
270g of 6 groups of blueberry powder of examples 1-3 and comparative examples 1-3 are weighed respectively, each part is mixed with 50ml of acidic distilled water, the mixture is mashed into pulp by a high-speed pounder, gauze is used for filtering for 2 times, and activated carbon is used for removing pigments. Then, the mixture is centrifuged for 5min (4000 r/min), the supernatant is taken and the volume is adjusted to 100ml, 10ml of the supernatant is taken in each test tube, and 3 samples are taken in each test tube.
Transferring the extracted sample liquid into a 1000ml conical flask, immediately dripping the dye 2, 6-dichlorophenol indophenol standard solution into the micro burette until the color is pink, and taking the end point that the dye does not disappear within 15 s. Blank test: 10.00ml of the sample extract was sucked into a 100ml conical flask, and added with l drops of 10% hydrochloric acid, and dropped to pink with a dye, which did not disappear within 15s as an end point, and the content of the required vitamin c was calculated from the amount of the dye consumed during the titration, and the results are shown in Table 2.
The vitamin c content was calculated using the following formula.
Wherein V is the consumed dye amount (ml) of the titration sample extract, T is the amount of vitamin C (mg/kg) which can be oxidized per ml of dye, A is the constant volume (100ml) of the sample extract, and A is1For taking up at the time of titrationThe volume of the sample extract (10ml) and W is the amount of the sample contained in the sample extract (6 g).
TABLE 2
Serial number
|
Vitamin c content/(mg/kg)
|
Example 1
|
688
|
Example 2
|
694
|
Example 3
|
644
|
Comparative example 1
|
273
|
Comparative example 2
|
184
|
Comparative example 3
|
335 |
From table 2, it can be seen that the case of vitamin c is similar to that of anthocyanins, and that the full low temperature processing with a single component processing scheme without a protectant reduces decomposition of heat sensitive components.
The disclosure of the present invention is not limited to the specific embodiments, but rather to the specific embodiments, the disclosure is to be accorded the widest scope consistent with the principles and novel features disclosed herein.