CN114034691B

CN114034691B - Method for identifying and grading dried orange peel

Info

Publication number: CN114034691B
Application number: CN202111217028.7A
Authority: CN
Inventors: 孙东; 陈明权; 商雪莹; 江森; 石洪超; 何风雷; 覃仁安
Original assignee: Guangzhou Baiyunshan Chen Liji Pharmaceutical Factory Co ltd
Current assignee: Guangzhou Baiyunshan Chen Liji Pharmaceutical Factory Co ltd
Priority date: 2021-10-19
Filing date: 2021-10-19
Publication date: 2022-06-14
Anticipated expiration: 2041-10-19
Also published as: CN114034691A

Abstract

The invention relates to a method for identifying and grading dried orange peel, which relates to an identification step for determining the category of a dried orange peel sample according to the colorimetric value result of a dried orange peel water extract and an identification step for determining the category of the dried orange peel sample according to the property result of the dried orange peel. The identification and classification method can objectively and accurately reflect the quality of the dried orange peel. And the result reproducibility is good, and the technology inheritance difficulty is small. Meanwhile, the identification grading method provided by the invention has strong practicability and good correlation. On the whole, the invention establishes an intuitive and quantitative pericarpium citri reticulatae evaluation method, breaks through an evaluation framework based on annual quality, is beneficial to promoting the high-quality development of the pericarpium citri reticulatae industry, and provides a new idea and a new technical support for the perfection of the pericarpium citri reticulatae quality standard.

Description

Method for identifying and grading dried orange peel

Technical Field

The invention belongs to the technical field of quality control of traditional Chinese medicinal materials, and particularly relates to an identification and classification method of dried orange peel.

Background

The 2020 edition of Chinese pharmacopoeia defines "pericarpium Citri Tangerinae" as dried mature pericarp of Citrus reticulata Blanco and its cultivated varieties (Citrus reticulata 'Chachi' etc.), wherein the pericarp of Citrus reticulata from Rutaceae is "Guang Chen Pi".

The price difference between the dried orange peels in different years is large, and the price is higher the longer the year is, the higher the price is. Therefore, no-old merchants in the market earn high profits for making old and new peels as old and new peels, and the market disorder seriously affects the healthy development of the dried orange peel industry. Therefore, the establishment of the quality grade evaluation method of the dried orange peel has important significance.

The traditional evaluation methods for the quality of dried orange peel include: according to the local standard DB 4407/T70-2021 geographical indication product Xinhui dried orange peel, the dried orange peels with different maturity such as green tangerine peels, reddish peels, scarlet peels and the like are classified into three grades of 'first-class product', 'second-class product' and 'third-class product', but the classification standard is mainly divided based on the sensory information such as the sheet size, the uniform degree of the thickness of the peels, the texture, the smell, the integrity of the sheets and the like of the dried orange peels, and the conditions such as the existence of impurities, worm damage, mildew, scab, skin burning and the like, and has no objective quantitative index. The method for testing the quality grade of the dried orange peel by the local standard mainly depends on the traditional experience identification methods such as a visual method, a hand feeling method and an olfaction method, and most of the traditional experience identification methods have strong subjectivity, relatively poor accuracy and poor repeatability of judgment results.

Therefore, how to objectively and accurately evaluate the dried orange peel is a technical problem to be solved urgently.

Disclosure of Invention

Based on the above, the main purpose of the invention is to provide the method for identifying and grading the dried orange peel, and the dried orange peel is identified by adopting the method for identifying and grading the dried orange peel, and the obtained result can objectively and accurately reflect the quality of the dried orange peel.

The purpose of the invention can be realized by the following technical scheme:

an identification method of dried orange peel, comprising the following steps:

soaking pericarpium Citri Tangerinae sample in water to obtain water extract,

obtaining the L value and a value of the color of the water leaching solution,

and analyzing the L and a values, and determining the category of the dried orange peel sample according to the result of the colorimetric values obtained by analysis.

In one embodiment, the step of obtaining the L and a values comprises: and shooting the water leaching solution, and introducing the obtained image into image processing software for analysis to obtain the L value and a value of the image as the L value and a value of the water leaching solution color.

In one embodiment, the shooting conditions include:

the camera adopts a Canon EOS M50 Mark II micro single camera, a manual exposure mode, an aperture value f/7.1, an exposure time 1/100s, an ISO speed 125, a flash lamp forbidden mode, an exposure compensation 0 step, an exposure simulation forbidden mode, a focal length 35mm and vertical shooting;

The photostudio adopts the small-size photostudio of Travor F60, white background, LED light source, 126 LED lamp pearls, colour temperature 5500K, luminance 15000LUX, the level is provided with the colorless transparent glass board in the photostudio, be provided with colorless transparent container on the colorless transparent glass board, the water logging liquid is arranged in among the colorless transparent container, the degree of depth is 1.5cm ~ 2cm, liquid level distance the distance of the camera lens of camera is 30cm, colorless transparent glass board or/and the luminousness of colorless transparent container is more than or equal to 95%, colorless transparent container is flat cylindrical container.

In one embodiment, the liquid level of the water immersion liquid is flush with the upper port of the colorless transparent container.

In one embodiment, the image processing software employs Photoshop CS 5.

In one embodiment, the authentication method further comprises: and after the image is obtained by shooting the water leaching solution, comparing the image by using a color chart, screening out an image which is consistent with the comparison result of the obtained color chart, and importing the image into the image processing software for analysis so as to obtain an L value and an a value. In one embodiment, the soaking time is more than or equal to 12 hours.

In one embodiment, the temperature of the soaking is 20-80 ℃.

In one embodiment, the size of the dried orange peel sample is controlled to be (0.2-2) cm x (0.2-2) cm.

In one embodiment, the amount of the water used for each 1g of the dried orange peel sample is 22-27 mL.

In one embodiment, determining the category of the dried orange peel sample according to the colorimetric value result obtained by the analysis comprises:

l is less than 50, a is more than or equal to 35, the dried orange peel sample corresponds to the high-temperature accelerated dried orange peel or the dried orange peel with other old making modes,

l is more than 75, a is less than or equal to 0, the dried orange peel sample corresponds to naturally aged dried orange peel stored under the condition that the air permeability is less than 5mm/s, and the historical years are less than or equal to three years,

l is more than or equal to 50 and less than or equal to 75, a is more than 0 and less than 35, and the dried orange peel sample corresponds to naturally aged dried orange peel stored under the condition that the air permeability is more than or equal to 5mm/s and less than or equal to 80mm/s, naturally aged dried orange peel stored under the condition that the air permeability is more than 80mm/s, naturally aged dried orange peel stored under the condition that the air permeability is less than 5mm/s for more than three years in history, high-humidity accelerated dried orange peel, burned orange peel or tea-water dyed dried orange peel.

The invention provides an identification method of dried orange peel, which comprises the following steps: and analyzing the inner capsule character of the dried orange peel sample, and determining the category of the dried orange peel sample according to the character result obtained by analysis.

In one embodiment, the inner capsule trait comprises an inner capsule color and/or an inner capsule texture.

In one embodiment, the determining the category of the tangerine peel sample according to the character result obtained by analyzing comprises the following steps:

the color of the inner capsule is light brown or brown, the dried orange peel sample is correspondingly stored in the naturally aged dried orange peel under the condition that the air permeability is more than or equal to 5mm/s and less than or equal to 80mm/s or the naturally aged dried orange peel under the condition that the air permeability is more than 80mm/s,

the color of the inner capsule is white-like, the dried orange peel sample is correspondingly stored in the naturally aged dried orange peel under the condition that the air permeability is less than 5mm/s,

the color of the inner capsule is dark brown, the dried orange peel sample corresponds to the high-temperature accelerated dried orange peel,

the color of the inner sac is dark inside and light outside, the grain of the inner sac is in a map shape, the dried orange peel sample corresponds to the high-humidity accelerated dried orange peel,

the color of the inner capsule is dark inside and light outside, the grains of the inner capsule have white ridges, the dried orange peel sample is used for accelerating dried orange peel, burning the peel or making old dried orange peel in other modes corresponding to high temperature,

the color of the inner sac is light inside and dark outside, the inner sac has no lines, and the dried orange peel sample corresponds to tea-dyed dried orange peel.

The identification and classification method of the dried orange peel comprises the following steps:

providing a dried orange peel sample, wherein the dried orange peel sample,

determining the category of the dried orange peel sample according to the result of the colorimetric value by adopting the identification method,

Determining the category of the dried orange peel sample according to the character result by adopting the identification method,

determining the comprehensive quality grade of the dried orange peel sample according to the following quality grading mode,

results of the character analysis	L＜50，a≥35	L＞75，a≤0	50≤L≤75，0＜a＜35
				The color of the inner bag is dark inside and light outside	Inferior grade	Inferior grade	Inferior grade
The color of the inner bag is light inside and dark outside	Inferior grade	Inferior grade	Inferior grade
				Tan color	Inferior grade	Inferior grade	Inferior grade
Off-white color	Inferior grade	Good grade	Good grade
				Light brown or brown	Inferior grade	Good grade	Super grade

And identifying and grading the dried orange peel sample according to the determined comprehensive quality grade.

Compared with the prior art, the invention has the following beneficial effects:

the invention takes the water extract of dried orange peel as a detection object, detects colorimetric values L and a of the color of the water extract, and distinguishes the category of the dried orange peel according to the colorimetric value analysis result. The identification method is used for identifying the dried orange peels based on the chromatic value of the water extract, the color of the water extract is more uniform than that of powder, the deviation of quantized data is smaller, the color of the water extract is more stable (for example, the water extract is not easy to change), and artificial old-making factors can be eliminated to a certain extent, so that the identification method can objectively and accurately reflect the quality of the dried orange peels. And the result reproducibility is good, and the technology inheritance difficulty is small. Meanwhile, the identification method provided by the invention has strong practicability (is rapid and simple), and good correlation (can better reflect the difference of the dried orange peels from different sources). The identification method is matched with the identification of the tangerine peel inner capsule character, the intuitive and quantized tangerine peel quality grade identification method is established on the whole, the evaluation frame of the quality in annual theory is broken through, a reliable means is provided for tangerine peel quality evaluation and quality grade division, the quick and accurate quality grade identification method of tangerine peel quality is good and bad, the promotion of the high-quality development of the industry of the citrus peel is facilitated, and a new thought and a new technical support are provided for the perfection of the quality standard of the citrus peel.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a technical roadmap for the present invention;

FIG. 2 is a comparison graph of three years of aged pericarpium Citri Tangerinae in three storage modes;

FIG. 3 is a diagram of appearance of different types of dried orange peels; wherein WG1(S16) is dried orange peel aged for more than or equal to 3 years, WG2(S11) is dried orange peel aged for less than 3 years, WG3(S31, S34) is high-temperature accelerated dried orange peel, WG4(S42) is high-humidity accelerated dried orange peel, WG5(S43) is baked skin, WG6(S40) is old dried orange peel made in other ways, WG7(S37) is dried orange peel dyed with tea, WG8(S39) is dried orange peel eaten by worms;

FIG. 4 is a comparison graph of the water leaching color of dried orange peel for different soaking times;

FIG. 5 is a graph comparing the effect of different soaking temperatures on aqueous immersion; in FIG. 5, the water control, Ma 1, Ma 2, Ma 3, Au 1, Au 2, Au 3, and the water control are sequentially performed from the right;

FIG. 6 is a schematic view of a device for taking a water immersion image of pericarpium Citri Tangerinae; wherein, 10 is a camera, 20 is a studio, 21 is an LED light source, 30 is a dried orange peel immersion liquid to be shot, 40 is a transparent glass plate, and 50 is a bracket for supporting the transparent glass plate;

FIG. 7 is a comparison chart of the two shooting methods of the pericarpium Citri Tangerinae water extract;

FIG. 8 is a color circle of water extract of different kinds of pericarpium Citri Tangerinae; TS1, TS 2: soaking in yellow-green water; TS8, TS 9: red brown water extract; TS3, TS4, TS5, TS 7: light yellow-golden yellow-orange yellow-brown water extract;

FIG. 9 is a macro-scale chart of the quality grade of citrus peel; wherein, L and a are colorimetric value indexes, L is brightness, the larger L is, the larger brightness is, and otherwise, the smaller L is; a is the red-green chroma, + a is the red direction, -a is the green direction, the larger + a, the more red the color.

Detailed Description

In order to facilitate an understanding of the present invention, the present invention will be described in more detail below. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as being limited to the embodiments or examples set forth herein. Rather, these embodiments or examples are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments or examples only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of two or more of the associated listed items, including any and all combinations of two or more of the associated listed items, any and all combinations of the associated listed items, or any and all combinations of the associated listed items.

The terms:

in the present invention, "first aspect", "second aspect", "third aspect", etc. are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or quantity, nor as implicitly indicating the importance or quantity of the technical features indicated.

In the present invention, the technical features described in the open type include a closed technical solution including the listed features, and also include an open technical solution including the listed features.

In the present invention, the numerical range is defined to include both endpoints of the numerical range unless otherwise specified.

The percentage contents referred to in the present invention mean, unless otherwise specified, mass percentages for solid-liquid mixing and solid-solid mixing, and volume percentages for liquid-liquid mixing.

The percentage concentrations referred to in the present invention are, unless otherwise specified, the final concentrations. The final concentration refers to the ratio of the added component in the system after the component is added.

The temperature parameter in the present invention is not particularly limited, and is allowed to be a constant temperature treatment or a treatment within a certain temperature range. The constant temperature process allows the temperature to fluctuate within the accuracy of the instrument control.

The identification method of dried orange peel provided by the invention has no time sequence limitation in the related steps.

The industry standard DB44T 604-2009 geographical indication product Xinhui dried orange peel divides the years of the Xinhui dried orange peel into three categories, namely the production year, the historical year and the aging year, and explains the three years. Wherein:

production year refers to the year of harvesting fruits and processing the fruits into pericarps, and indicates the year in which the samples are produced;

The historical year refers to the year calculated by subtracting the production year and one year from the inspection year, and indicates how long the sample is;

and thirdly, aging years refer to the aging degree of the dried orange peels expressed by years, which indicates that the sample achieves the aging level of a corresponding grade.

Also, other terms of art are defined by the standard, such as:

aging: under the condition of natural dry and ventilation, the product is stored in a packaging container with good air permeability, and the color, the fragrance, the taste and the components of the dried orange peel are changed along with the change of the fading and the changing of the effective contents of the dried orange peel along with the change of time.

"degree of aging": the sensory properties of Xinhui dried orange peel in different periods are expressed by years.

"burn skin": the fresh orange peel contains more sugar, is easy to absorb moisture, and if the fresh orange peel is stacked for a long time and is not turned and dried in the sun in time, the temperature is increased, rapid sugar alcoholysis is induced, and carbonization and black peel deterioration are caused.

"worm eaten": during the storage period, the dried skin is mainly eaten by pests such as a khaki, a coffee bean weevil and the like, the dried skin is eaten in an orange channel, and then the dried skin is perforated by an orange hole and finally becomes moth powder to lose the commodity value.

"other distressing means": other distressing means besides high temperature acceleration, tea dyeing and high humidity acceleration.

The tangerine peel is characterized in that the tangerine peel on the outer layer of the inner capsule of the tangerine peel presents a raised white ridge stripe, and the shape is called as a white ridge.

The correspondence is only used for limiting the state, but not for limiting the acquisition mode. Also contemplated are dried orange peels of the same or similar quality obtained in different ways.

In a first aspect, the invention provides a method for identifying dried orange peel, which comprises the following steps:

soaking pericarpium Citri Tangerinae sample in water to obtain water extractive solution,

obtaining the value L and the value a of the color of the water leaching solution,

In the identification method provided by the invention, L and a are colorimetric value indexes, L is brightness, the larger L is, the larger brightness is, and otherwise, the smaller L is; a is the red-green chroma, + a is the red direction, -a is the green direction, the larger + a, the more red the color.

In one example, the obtaining of the L and a values includes: and shooting the water leaching solution, and introducing the obtained image into image processing software for analysis to obtain the L value and a value of the image as the L value and a value of the water leaching solution color.

In one example, the conditions for photographing include:

The camera adopts a Canon EOS M50 Mark II micro single camera, a manual exposure mode, an aperture value f/7.1, exposure time 1/100s, ISO speed 125, flash lamp forbidding, exposure compensation 0 step, exposure simulation forbidding, a focal length 35mm and vertical shooting;

In the studio, a water immersion liquid sample in a transparent six-hole culture plate is placed on a common transparent glass plate with proper height for shooting, so that influence factors such as interference caused by a light reflection effect generated by the water immersion liquid during shooting are avoided. The color of the dried orange peel water extract filled in the transparent container is determined by adopting the method similar to suspended shooting, and the comparison is carried out by using a colorimetric card, so that the color of a sample in a shot photo is basically consistent with the color observed by naked eyes, and a novel method for quantifying the color of the dried orange peel water extract is conveniently established.

In one example, the level of the water immersion liquid is flush with the upper port of the colorless transparent container. Preferably, the colorless transparent container is a flat-bottomed six-well culture plate. The flat six-hole culture plate can adopt a disposable cell culture plate with the product brand name of 'Hu View', and the product specification is as follows: the material is pure polystyrene, the color is colorless and transparent, the flat bottom is flat, the depth is 16.6mm, and the size is 125mm multiplied by 85mm multiplied by 23 mm. Of course, other containers of similar dimensions to the flat six well plate may be used.

In order to make the surface of the aqueous extract flush with the upper port of the six-well culture plate, 15mL of the aqueous extract may be added per well. The water immersion liquid can be transferred into the six-hole culture plate by a liquid transfer gun, so that the liquid level is flush with the upper end opening of the hole, the interference generated by the edge effect of the liquid can be reduced, and the water immersion liquid can be ensured not to overflow in the hole.

In one example, the image processing software employs Photoshop CS 5.

In one example, the authentication method further comprises: and after the water leaching solution is shot to obtain the image, comparing the image by using a color comparison card, screening out an image which is consistent with the comparison result of the obtained color comparison card, and importing the image into the image processing software for analysis so as to obtain an L value and an a value.

In one example, the soaking time is more than or equal to 12 hours. The length of the soaking period may be selected from, including but not limited to, any one of the following or a range of lengths between any two of the following: 12h, 14h, 16h, 18h, 20h, 22h, 24h, 26h, 28h and 30 h.

In one example, the temperature of the soaking is 20 ℃ to 80 ℃. The temperature of soaking may be selected from, including but not limited to, any one of the following soaking temperatures or a temperature range between any two soaking temperatures: 20 deg.C, 25 deg.C, 30 deg.C, 35 deg.C, 40 deg.C, 45 deg.C, 55 deg.C, 60 deg.C, 65 deg.C, 70 deg.C, 75 deg.C, 80 deg.C.

In one example, the size of the dried orange peel sample is controlled to be (0.2-2) cm x (0.2-2) cm. The size of the dried orange peel sample can be controlled, including but not limited to the following specifications or a size range between any two specifications: 0.2cm × 2cm, 0.4cm × 2cm, 0.6cm × 2cm, 0.8cm × 2cm, 1.0cm × 2cm, 1.2cm × 2cm, 1.4cm × 2cm, 1.6cm × 2cm, 1.8cm × 2cm, 2cm × 2cm, 0.2cm × 0.2 cm.

In one example, the amount of water used per 1g of the pericarpium citri reticulatae sample is 22mL to 27mL, for example, the amount of water used per 1g of the pericarpium citri reticulatae sample is 22mL, 23mL, 24mL, 25mL, 26mL, 27 mL.

In one example, determining the category of the dried orange peel sample according to the colorimetric value result obtained by the analysis comprises:

l is more than or equal to 50 and less than or equal to 75, a is more than 0 and less than 35, the dried orange peel sample corresponds to naturally aged dried orange peel stored under the condition that the air permeability is more than or equal to 5mm/s and less than or equal to 80mm/s, naturally aged dried orange peel stored under the condition that the air permeability is more than 80mm/s, naturally aged dried orange peel stored under the condition that the air permeability is less than 5mm/s for more than three years in historical years, high-humidity accelerated dried orange peel, burned peel or tea-water dyed dried orange peel.

In a second aspect, the invention provides a method for identifying dried orange peel, which comprises the following steps: and analyzing the inner capsule character of the dried orange peel sample, and determining the category of the dried orange peel sample according to the character result obtained by analysis.

In one example, the inner sac shape comprises an inner sac color and/or an inner sac texture.

In one example, determining the category of the pericarpium citri reticulatae sample according to the trait result obtained by the analysis comprises:

the color of the inner capsule is light inside and dark outside, the inner capsule has no lines, and the dried orange peel sample corresponds to tea-colored dried orange peel.

providing a dried orange peel sample, wherein the dried orange peel sample,

The following embodiment establishes a method for identifying and grading the citrus reticulata blanco from a macroscopic level, mainly relates to identification of citrus reticulata blanco category from two aspects of citrus reticulata blanco inner sac character and citrus reticulata blanco water extract color, and has a technical route shown in figure 1. It can be understood that, in the process of identifying the pericarpium citri reticulatae sample, identification can be performed by starting from the characteristics of the pericarpium citri reticulatae inner capsule (corresponding to the identification method 1 in fig. 1), or identification can be performed by selecting the color of the pericarpium citri reticulatae water extract as the standard (corresponding to the identification method 2 in fig. 1), or the identification and the identification are combined to perform comprehensive quality grade identification. More specifically, in the following embodiments, citrus reticulata blanco peel of different years, different ripeness degrees and different storage modes is taken as a research object, and a method for identifying citrus reticulata blanco peel by combining sensory evaluation and colorimetric values of water extract is adopted, so that corresponding methods for identifying citrus reticulata blanco peel are respectively established from different angles such as the properties of an inner capsule of the citrus reticulata blanco peel and the color of the water extract; and combining the 2 identification methods to construct the quality grade identification method of the citrus peel from the macroscopic aspect.

The test methods described in the following examples of the present invention are all conventional methods unless otherwise specified; the reagents and biomaterials, if not specifically mentioned, are commercially available.

1 Instrument and reagent

1.1 Instrument

The device comprises a Canon EOS M50 Mark II micro single camera (Canon, Japan, Canon Co., Ltd.), a Travor F60 small photostudio (Shenzhen tourist science and technology Co., Ltd.), an Eppendorf manual single-channel adjustable liquid-transferring gun (German Eppendorf, the range is 0.5-5 mL), a six-hole culture plate (Hu View), a Chinese architectural color card CBCC (GBT 15608-.

1.2 reagents

Tap water.

1.3 test specimens

The main sources of the test samples of the research are the collection of a new-party dried orange peel base, the purchase of a new-party production area, the directional purchase of local dried orange peel planting companies or cooperative companies and the like, the numbers of the test samples are S1-S43, the obtained wide dried orange peel samples are aged by three different storage modes (see table 1), and the samples are placed in a dry and ventilated environment; meanwhile, the information of the inner capsule character, the maturity and the like of all the dried orange peel samples is described and detailed in table 2. The above samples were identified as pericarp of Citrus reticulata of Rutaceae by professor yellow sea wave of the institute of Chinese medicine identification and development of Guangzhou university of traditional Chinese medicine.

TABLE 1 storage mode of dried orange peel sample

Serial number	Storage mode	Air permeability	Encoding
					1	Sacking, net-box packing, etc	Good air permeability (air permeability > 80mm/s)	DZ
2	Plastic bag open mouth, paper box package and the like	General air permeability (5 mm/s. ltoreq. air permeability. ltoreq.80 mm/s)	CK
				3	Sealing bags, glass jar seals, etc	Poor air permeability (air permeability < 5mm/s)	MF

TABLE 2, tangerine peel sample information table

Note: samples S30-S34 were identified as "high temperature accelerated citrus peel" in the literature, "research on aging method for determining citrus peel based on 5-hydroxymethylfurfural content and color difference in appearance"; the inner capsule of the dried orange peel has dark inside and light outside, and the outer orange peel presents a raised white ridge-shaped stripe, which is called as 'white ridge'. "-" represents sample information.

2 methods and results

2.1 Category identification based on the appearance of dried orange peel

2.1.1 study on appearance character change rule of pericarpium Citri Tangerinae aging process in different storage modes

Under the guidance of the theory of shape discrimination theory, based on the traditional character discrimination method, the characters of the citrus chachiensis peels from different sources are described as accurate and detailed as possible, including the color of the inner capsule, whether the inner capsule has cracks, white ridge lines and the like, and the quality of the citrus chachiensis peels is preliminarily evaluated, so that a sensory discrimination table is established.

The method comprises the steps of taking Guangzhou dried orange peels (S11, S17 and S18) from the same source as research objects, collecting research samples in 11 months in 2017 in the same Xinhui dried orange peel base, drying the research samples in the sun, storing the research samples in three storage modes of sealed bag packaging (MF), jute bag packaging (DZ) and carton packaging (CK), and observing the colors of the inner capsules of the dried orange peels and the existence of cracks in the inner capsules after three years of storage, wherein the results are shown in a table 3 and a figure 2.

The storage period is regularly observed whether mildew, worm damage and other phenomena exist, so that the storage process of the dried orange peel is ensured not to deteriorate; regarding the selection of the appearance color index, the color of the outer skin of the dried orange peels with different ripeness degrees is greatly different; the initial color of the tangerine peel inner capsule is white and is not influenced by the maturity, so the color of the tangerine peel inner capsule is selected as an observation index.

TABLE 3 appearance change of dried orange peel aging process in different storage modes

As can be seen from table 3, the dried orange peels with different storage modes have obvious differences in appearance after being stored for three years; referring to fig. 2, the color of the sacs and cartons is changed from white to light brown, while the color of the inner sacs of the sealed tangerine peel is still white. The turtle crack of the inner capsule also has difference in the dried orange peels with different storage modes, wherein the dried orange peel inner capsule in the sacs has deep but less cracking lines, and the dried orange peels packaged in the cartons and the dried orange peels packaged in the sealing bags have no turtle crack.

The appearance character changes indicate that the aging degrees of the dried orange peels in different storage modes are different, and the aging degrees are sequentially S17 > S18 > S11. And by combining the air permeability of the three storage modes, the aging of the dried orange peel requires the dried orange peel to contact oxygen and moisture in the environment, and the aging speed of the dried orange peel is very slow even the dried orange peel does not age under the sealed condition.

2.1.2 class identification

As can be seen from Table 3 and FIG. 2, there is a large difference between the appearance properties of dried orange peels with different aging degrees. Therefore, the classification method is adopted in the research, and the classification of the dried orange peel samples from different sources is distinguished from the aspects of the dried orange peel inner capsule color, the inner capsule tortoise cracks, the white ridge lines and other appearance characters by combining with the professional terms of traditional Chinese medicine, and the result is shown in table 4 and fig. 3.

TABLE 4 Category differentiation based on the appearance Properties of Citrus Tanguticus

Note: because the damage of the inner capsule of the orange peel eaten by worms is obvious, the identification according to the properties of the inner capsule is not needed.

2.2 identifying categories based on the color of the water extract of the dried orange peel

The color of the inner capsule of the dried orange peel can obviously change in the aging process, and the evaluation of the color is easy to cause deviation due to the influence of subjective individual difference and insensitivity, thereby greatly influencing the application and popularization of the color in the aspect of quality evaluation. Therefore, the sensory evaluation of the color of the dried orange peel also needs to be objectively quantified by means of a color card, a color detection instrument, a machine vision technology, a shooting combined computer image processing means and the like. Through color quantization, subjective colors can be digitally expressed, the colors of a certain object can be measured, and the colors between the object and the object or a plurality of the object can be quantized and compared, so that the practical value of the colors as the basic attributes of the object is greatly improved.

Because the inner and outer skins of the dried tangerine peel are uneven and irregular, most of the tangerine peel has heterogeneous color; and part of instruments are difficult to be applied to production inspection and detection due to high manufacturing cost and the like. In view of this, in order to avoid the above adverse factors and consider the generalizability of the measurement method, the research takes the water extract of the dried orange peel as a research object, quantifies the color of the water extract by means of shooting combined with computer image processing, and simultaneously adopts color chart comparison to confirm the feasibility of the method; and by analyzing the color of the water extract of Guangzhou dried orange peel, researching the category identification of Guangzhou dried orange peel and formulating the identification standard thereof to realize the rapid identification of the category of Guangzhou dried orange peel.

The colorimetric evaluation system used in this study was CIE1976 uniform color space, i.e., CIE-Lab system, which used L, a, b to objectively express color. L is brightness, the larger L is, the larger brightness is, otherwise, the smaller is; a is the degree of red and green, a is the direction of red, a is the direction of green, the greater + a, the more red the color; b is the shade of yellow-blue, + b is the direction of yellow, -b is the direction of blue, the greater + b, the more yellow the color. Meanwhile, the shooting mode (angle, height and brightness) is continuously optimized, and a quantification method for the color of the water extract is established.

2.2.1 preparation of aqueous extract of pericarpium Citri Reticulatae

Firstly, manually tearing or shearing a dried orange peel sample into fragments (the length and the width are both between 0.5cm and 1.2 cm), weighing 2.0g of the fragments, placing the fragments in a 150mL beaker, adding 50mL of water (28 ℃), and standing for more than 12 h; then filtering with gauze or filter screen. And 15mL of the culture plate is transferred into a six-hole culture plate by using a liquid transfer gun, and 1 sample/hole is reserved.

Determining the optimal soaking time of the dried orange peel sample: the color of the tangerine peel water extract is changed by comparing different time periods of adding water and soaking for 1h, 2h, 4h, 8h, 12h, 18h and 24h in the subject group, and the result shows that when the soaking time of the tangerine peel sample is within 12h, the color of the tangerine peel water extract is continuously deepened along with the prolonging of the soaking time; however, after the soaking time is 12h, the color of the water extract of the dried orange peel does not change basically (see fig. 4), which indicates that the optimal soaking time of the dried orange peel is 12h or more.

Determining the optimal soaking temperature of the dried orange peel sample: putting 1.5g of a blocky Xinhui dried orange peel sample with the width of about 1cm into a 200mL beaker, adding 50mL of water (the initial temperature is 21 ℃, 55 ℃ and 85 ℃) for soaking, and standing at room temperature while comparing the influence of different soaking time (0.5h, 1.0h, 3.0h, 5.0h and 7.0h) on the color of the dried orange peel water extract. Wherein:

The corresponding treatments of the dried orange peel sample S17 at the soaking temperature of 21 ℃, 55 ℃ and 85 ℃ are respectively marked as 'hemp 1', 'hemp 2' and 'hemp 3';

the corresponding treatments of the dried orange peel sample S32 at the soaking temperature of 21 ℃, 55 ℃ and 85 ℃ are respectively marked as 'gold 1', 'gold 2' and 'gold 3';

the color of each treatment was recorded at 0.5h, 1h, 3h, 5h, 7h soaking as shown in FIG. 5.

As can be seen from fig. 5, the influence of temperature on the water immersion liquid is insignificant.

2.2.2 method for measuring color of water extract

(1) Placing of water immersion liquid sample and image acquisition

And (4) using a liquid-transferring gun to transfer 15mL of tangerine peel water extract into a six-hole culture plate, and ensuring that the liquid level is flush with the upper ports of the holes. Firstly, fixing a bracket with the height of about 12cm in the middle of each of two sides in a camera chamber; then a piece of transparent glass with proper size is placed at the upper end of the bracket, so that the distance between the transparent glass and the bottom layer of the camera box is about 12 cm; a six-well culture plate filled with a sample of aqueous extract of pericarpium Citri Tangerinae was then placed in the central area of the glass plate, as shown in FIG. 6. In fig. 6, 10 is a camera, 20 is a studio, 21 is an LED light source, 30 is a water immersion liquid of dried orange peel to be photographed, 40 is a transparent glass plate, and 50 is a bracket for supporting the transparent glass plate.

All dried orange peel water extract samples are uniformly shot in a Travr F60 small photostudio, white is used as a background, LEDs are used as light sources, 126 LED lamp beads are used, the color temperature is 5500K, and the brightness is 15000 LUX; the camera lens is vertically placed, and the distance between the front end of the camera lens and a measured object is 30 cm; the camera (manual exposure mode; aperture value f/7.1, exposure time 1/100 seconds, ISO speed 125, flash disabled; exposure compensation 0 step; exposure simulation disabled; focal length 35mm) is set and fixed.

And finally, deriving all pictures in the camera, extracting the values of L, a and b respectively by using Photoshop CS5 image processing software, randomly extracting for 3 times at any part (except edges) in each sample picture, and calculating an average value to obtain the values of L, a and b of each sample.

(3) Optimization of dried orange peel water extract sample shooting method

The photographic device is optimized to avoid influence factors such as interference caused by light reflection effect generated by dried orange peel water immersion liquid during shooting; compare with

Directly placing a dried orange peel water extract sample to be shot at the bottom of a photostudio;

secondly, a method similar to hanging shooting is adopted, firstly a piece of transparent glass with proper size is placed in the middle of two sides in a camera box, the upper end of a bracket with the height of about 12cm is fixed at the middle part of the two sides, and then a dried orange peel water immersion liquid sample to be shot is placed on a transparent glass plate.

Meanwhile, comparing by using a color comparison card, taking a Chinese building color card CBCC as a standard, placing the same dried orange peel water extract sample in a view field in a place which is bright under a white light source, placing a standard color comparison card in a reference view field, visually observing and comparing the two view fields by a normal color observer, and recording the color value of the standard color comparison card which is most similar to the color presented by the water extract sample. The results are shown in Table 5 and FIG. 7.

TABLE 5 comparison of quantization methods for various colors

As can be seen from Table 5, the colorimetric values of three dried orange peel water extract samples obtained by two shooting methods have larger difference, wherein the colorimetric values of L and a measured by the two color quantification methods of the shooting method II and the color card measurement are basically consistent; as can be seen from FIG. 7, the color of the picture obtained by the shooting method (I) is darker than that of the picture obtained by the shooting method (II).

The results show that the color of the picture of the dried orange peel water extract obtained by the shooting method II can more truly reflect the color condition observed by naked eyes; therefore, the adoption of the 'shooting method-' for color quantification is feasible, close to the real color and can be popularized.

2.2.3 methodology examination

(1) Stability survey

Sample S17 was prepared by operating dried orange peel aqueous extracts in parallel according to the aforementioned "2.2.2 aqueous extract color measurement method" with 0h, 1h, 3h, 5h, 7h, and 9h as time nodes, and the measurement values were recorded, and the results are shown in Table 6.

TABLE 6 method stability examination

As can be seen from Table 6, the RSD values of the measured colorimetric values L, a and b of the dried orange peel water extract by the method of shooting and combining the computer image processing means between 0h and 9h are respectively 1.16%, 3.78% and 1.60%, which shows that the method has better stability.

(2) Precision survey

The water extract of sample S22 was used as a study subject, and dried orange peel water extract was continuously photographed 6 times according to the aforementioned operation method of "2.2.2 water extract color measurement method", and Photoshop CS5 was introduced, and the measurement value was recorded, and the RSD value thereof was calculated, and the results are shown in Table 7.

TABLE 7 examination of camera shooting precision

As can be seen from table 7, in 6 times of photographing, RSD of the water extract colorimetric values L, a, b of the dried orange peel are 0.84%, 2.91%, 0.84%, respectively, and the result of the color data is stable and reliable, indicating that the precision of the instrument is good.

2.2.4 quantification methods and results

The water extract color and colorimetric value of all dried orange peel samples were measured by the method of "shooting combined with computer image processing", see table 8.

TABLE 8 chroma value of the water extract of pericarpium Citri Reticulatae

As can be seen from table 8, the water extracts of citrus reticulata blanco have large differences in colorimetric values in different years, wherein the differences in colorimetric values L and a are significant, while the differences in b are insignificant, and the water extracts are mainly classified into five categories, i.e., yellow-green, light-yellow, golden-yellow, brown-yellow, and brown-red. The colorimetric values of the dried orange peel water extract in different years have a certain distribution range, the L value is between 36 and 86, and the a value is between-6 and 41. Wherein, the top three of the minimum value L and the maximum value a are high-temperature accelerated tangerine peels (S30) and other old-making tangerine peels (S40, S41), the chroma value is within the distribution range L49, a is not less than 36, and the color of the tangerine peel water extract of the above four samples is the deepest, namely brownish red through the data of the L value related to the brightness. Simultaneously comprehensively considering the colorimetric values of the S28 sample (L is 52 and a is 33) ranked fifth to the minimum value and the colorimetric values of the S33 sample (L is 54 and a is 35) ranked fifth to the maximum value and the high-temperature accelerated dried orange peel; therefore, the colorimetric value indexes L < 50 and a > 35 are feasible to be used as the preliminary discrimination standard of the high-temperature accelerated tangerine peel and the tangerine peel in other old-making modes.

From table 8, 6 samples with orange peel water extract color yellow-green are from S1 to S6, etc., the a values are all less than or equal to 0, and the L values are all more than 75; as can be seen from Table 2, the years of history are less than three years. It can be seen that the colorimetric value indexes L > 75 and a ≦ 0 are feasible as the criteria for identifying dried orange peels for less than three years in the past years.

2.2.6 Category discrimination

It can be seen from tables 1 and 8 that different types of dried orange peels such as dried orange peels with less than three years and dried orange peels with more than three years, high-temperature accelerated dried orange peels, other old-making methods and naturally aged dried orange peels can be distinguished according to the colorimetric values L and a of the water extract. Based on this, the present study establishes a method for identifying the category of citrus grandis and color circle according to the range of the colorimetric values L and a, as shown in table 9 and fig. 8.

TABLE 9 Classification based on orange peel water extract color

Note: because the damage of the inner capsule of the orange peel eaten by worms is obvious, the identification according to the color of the water extract is not needed.

Combining table 8, the tea water dyed dried orange peels S35, S36, S37(L values 50-57, a values 16-23), burned peels S43(L values 66, a values 17), high-humidity accelerated dried orange peels S42(L values 55, a values 33) and partial high-temperature accelerated dried orange peels S32(L values 70, a values 15) are in the range of 50-75L and 0-35 a; therefore, the colorimetric value of the water extract can be used as one of evaluation methods for identifying and grading the dried orange peel, but the comprehensive analysis and judgment are required to be carried out by combining other evaluation methods such as appearance properties and the like.

3 establishing method for identifying quality grade of Guangzhou dried orange peel

In conclusion, the types of the dried orange peels can be identified to a certain extent from the aspects of appearance and color of the dried orange peels and the water extract; it can be seen from the combination of tables 4 and 9 that the naturally aged orange peel can not be accurately distinguished from the accelerated and aged orange peel only by a single identification method. Therefore, in the identification of the quality grade of the dried orange peel, the properties of the inner capsule and the color of the water extract are required to be combined for judgment.

Through the relevance analysis of the two identification methods, most of different types of samples divided by the identification methods can be in one-to-one correspondence. Therefore, the research integrates the two types of identification methods, and the quality grade of the citrus chachiensis maxim is divided into three grades of 'inferior grade', 'good grade' and 'superior grade' on a macroscopic level, and the result is shown in figure 9.

All possible combinations of the technical features of the above embodiments may not be described for the sake of brevity, but should be considered as within the scope of the present disclosure as long as there is no contradiction between the combinations of the technical features. The above-mentioned embodiments only express several embodiments of the present invention, which is convenient for specific and detailed understanding of the technical solutions of the present invention, but the present invention should not be construed as being limited to the scope of the invention.

It should be noted that various changes and modifications can be made by those skilled in the art without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. It should be understood that the technical solutions provided by the present invention, which are obtained by logical analysis, reasoning or limited experiments, are within the scope of the present invention as set forth in the appended claims. Therefore, the protection scope of the present patent shall be subject to the content of the appended claims, and the description and drawings can be used to explain the content of the claims.

Claims

1. The identification method of the dried orange peel is characterized by comprising the following steps:

analyzing the L value and the a value, and determining the category of the dried orange peel sample according to the colorimetric value result obtained by analysis;

the soaking time is more than or equal to 12 hours;

the soaking temperature is 20-80 ℃;

the size of the dried orange peel sample is controlled to be (0.2-2) cm x (0.2-2) cm;

the dosage of the water corresponding to each 1g of the dried orange peel sample is 22 mL-27 mL;

Determining the category of the dried orange peel sample according to the colorimetric value result obtained by the analysis comprises the following steps:

2. The method of claim 1, wherein the step of obtaining L and a values comprises: and shooting the water leaching solution, and introducing the obtained image into image processing software for analysis to obtain the L value and a value of the image as the L value and a value of the color of the water leaching solution.

3. The method of claim 2, wherein the photographing conditions include:

The photostudio adopts the small-size photostudio of Travor F60, white background, LED light source, LED lamp pearl 126, colour temperature 5500K, luminance 15000LUX, the level is provided with colorless transparent glass board in the photostudio, be provided with colorless transparent container on the colorless transparent glass board, the water logging liquid is arranged in the colorless transparent container, the degree of depth is 1.5cm ~ 2cm, liquid level distance the distance of the camera lens of camera is 30cm, colorless transparent glass board or/and the luminousness of colorless transparent container is more than or equal to 95%, colorless transparent container is flat cylindrical container.

4. The method for identifying citrus peel according to claim 3, wherein the level of the aqueous extract is flush with the upper port of the colorless transparent container.

5. The method for identifying citrus peel according to claim 2, wherein the image processing software employs Photoshop CS 5.

6. The method of identifying citrus peel according to any one of claims 2 to 5, further comprising: and after the water leaching solution is shot to obtain the image, comparing the image by using a color comparison card, screening out an image which is consistent with the comparison result of the obtained color comparison card, and importing the image into the image processing software for analysis so as to obtain an L value and an a value.

7. The identification method of the dried orange peel is characterized by comprising the following steps: analyzing the inner capsule character of the dried orange peel sample, and determining the category of the dried orange peel sample according to the character result obtained by analysis;

the inner sac character comprises an inner sac color and/or an inner sac line;

determining the category of the dried orange peel sample according to the character result obtained by analysis comprises the following steps:

8. The method for identifying and grading the dried orange peel is characterized by comprising the following steps of:

providing a dried orange peel sample, wherein the dried orange peel sample,

the identification method according to any one of claims 1 to 6, wherein the category of the pericarpium Citri Tangerinae sample is determined according to the result of colorimetric value,

the identification method according to claim 7, determining the category of the pericarpium Citri Tangerinae sample according to the trait result,

character analysis knotFruit L*＜50，a*≥35 L*＞75，a*≤0 50≤L*≤75，0＜a*＜35 The color of the inner bag is dark inside and light outside Inferior grade Inferior grade Inferior grade The color of the inner bag is light inside and dark outside Inferior grade Inferior grade Inferior grade Tan color Inferior grade Inferior grade Inferior grade Off-white color Inferior grade Good grade Good grade Light brown or brown Inferior grade Good grade Super grade