阅读说明：本技术 一种延长鲜食枸杞保鲜期的方法 (Method for prolonging preservation period of fresh-eating medlar ) 是由 张鹏 李江阔 贾晓昱 刘玲 于 2021-03-04 设计创作，主要内容包括：本发明公布了一种延长鲜食枸杞保鲜期的方法,该方法为采前1-甲基环丙烯、海洋鱼蛋白肽和ε-聚赖氨酸构成的营养保鲜剂进行喷雾处理,次日采摘后当天装入便携式气调箱内12～16 h内运输至目的地,在冷库经预冷后,加入太赫兹保鲜包和1-MCP保鲜包,并加入适量干冰后扣盖贮藏。这种保鲜方法可以有效减缓鲜食枸杞的软化和腐烂,同时保证枸杞叶片鲜绿,保鲜期延长至50 d以上。(The invention discloses a method for prolonging the fresh-keeping period of fresh-eating medlar, which comprises the steps of collecting a nutritional preservative consisting of 1-methylcyclopropene, marine fish protein peptide and epsilon-polylysine for spray treatment, loading the fresh-keeping agent into a portable air-conditioning box for 12-16 h to be transported to a destination on the day after the fresh-keeping agent is picked the next day, precooling the fresh-keeping agent in a cold storage, adding a terahertz fresh-keeping bag and a 1-MCP fresh-keeping bag, adding a proper amount of dry ice, and then covering the fresh-keeping agent for storage. The fresh-keeping method can effectively slow down the softening and the decay of the fresh medlar, simultaneously ensure the freshness and the green of the medlar leaves, and prolong the fresh-keeping period to more than 50 days.)

1. A method for prolonging the preservation period of fresh medlar is characterized by comprising the following steps:

step 1: the method comprises the following steps of (1) preparing a nutritional preservative for the medlar reaching a physiological maturation stage before harvesting, putting the medlar into a sprayer, manually spraying 10-30 mL of the nutritional preservative per kg of fruits, and uniformly spraying the nutritional preservative on the surface of the medlar to be harvested; the nutrient preservative is composed of 1-methylcyclopropene, marine fish protein peptide and epsilon-polylysine, 0.8-1.2 g of 1-methylcyclopropene subjected to alpha-cyclodextrin and chitosan curing treatment, 4-6 g of marine fish protein peptide and 1.0-2.0 g of epsilon-polylysine are required to be added into 1L of aqueous solution, and the mass of the nutrient preservative is calculated according to the volume to be used;

step 2: after the surfaces of the Chinese wolfberry are dry, picking up the Chinese wolfberry completely, putting the Chinese wolfberry into a portable air conditioning box, adding an ice box in the middle of the air conditioning box before buckling a cover, then buckling the cover for loading, ensuring that the Chinese wolfberry is transported to a destination within 12-16 h, and timely putting the Chinese wolfberry into a refrigeration house to open the cover of the air conditioning box for precooling;

and step 3: and (3) fully precooling the medlar, adding a terahertz freshness protection package and a 1-MCP freshness protection package, adding a proper amount of dry ice, immediately covering, and entering a storage stage.

2. The method for prolonging the shelf life of fresh-eaten medlar as recited in claim 1, wherein: the quality of the medlar contained in the portable air-conditioning box is 2.0-2.5 kg, the logistics time is 12-16 h, the medlar is transported to a destination, and CO in the box body₂The content is controlled to be 5-20%.

3. The method for prolonging the shelf life of fresh-eaten medlar as recited in claim 1, wherein: and after the destination is reached, the cold storage is put into the cold storage in time, the box cover is opened for precooling, the temperature of the cold storage is-0.5 ℃, and the precooling time is 18-24 h.

4. The method for prolonging the shelf life of fresh-eaten medlar as recited in claim 1, wherein: the number of the terahertz freshness preservation bags is related to the quality of the medlar, and 1 bag is added into every 1.0 kg of medlar; similarly, the quality of the 1-MCP fresh-keeping bag is related to the quality of the medlar, and 1 bag is added into every 2.5 kg of medlar.

5. The method for prolonging the shelf life of fresh-eaten medlar as recited in claim 1, wherein: the amount of the pre-cooled dry ice is determined according to CO in the box body₂Content determination, requiring tank CO₂The content is 6-8%The amount of the dry ice is 2-3 g.

6. The method for prolonging the shelf life of fresh-eaten medlar as recited in claim 1, wherein: in the storage stage, the temperature in the air conditioning box body is controlled to be-0.3 ℃, and CO is in the range of₂The content is maintained at 8-12%, O₂The content is maintained at 5-10%.

7. The method of claim 1 for prolonging the shelf life of fresh-eaten wolfberry fruit, which is used to prolong the shelf life of fresh wolfberry fruit and delay the softening and decay of fruit during storage.

Technical Field

The invention belongs to the technical field of storage and preservation of agricultural products, and particularly relates to a method for combining various preservation such as pre-harvest nutrition preservative treatment, modified atmosphere during transportation, artificial modified atmosphere combined modified atmosphere in a storage stage, physiological regulation, preservative preservation, accurate temperature control and the like.

Background

Chinese wolfberry fruit (Chinese wolfberry fruit)Lycium barbarumL.) and fruit of Lycium of Solanaceae is red and egg-shaped, and is originally produced in the north of China, because fruits are cultivated as medicines, the fruits are cultivated in the provinces, and besides the provinces, a plurality of provinces in the middle and the south of China are introduced for cultivation, and particularly, the fruits are cultivated in more and high yield in Ningxia and Tianjin areas. The fructus Lycii contains various chemical components including organic acids, alkaloids, and flavonoidsAnd pigments and the like, has the effects of resisting oxidation, resisting cancer, protecting the liver, protecting nerves, protecting eyesight, regulating blood sugar and blood fat, regulating immunity, preventing and treating cardiovascular and cerebrovascular diseases and the like, and has extremely high medicinal value and health-care function. The fresh Chinese wolfberry peel is thin and tender, has high water content, can change color and flavor when placed for 2-4 days at normal temperature, and the rot index gradually rises; after the fruit is placed for 8-10 days, the rot index of the fruit is increased sharply, and even the edible value is completely lost. So mostly be the dry fruit goods of matrimony vine in the market today, in the stoving of dry fruit of matrimony vine, soak, sunning in-process, nutrition loss degree is higher, and especially matrimony vine polysaccharide that the matrimony vine is rich loses seriously in dry fruit, can not be absorbed by the human body and utilize. Therefore, the method explores an optimal storage and fresh-keeping mode of the fresh medlar fruits, can reduce the loss of the medlar in the storage process, and has positive effect on the development of the medlar industry.

The air-regulating fresh-keeping method is a technique for inhibiting respiration of fruit and delaying its maturation and senility by changing gas component and concentration of storage environment. Compared with the cold storage, the storage mode can reduce the release amount of ethylene, thereby effectively maintaining the hardness and the quality of the fruits. Modified atmosphere storage is generally divided into modified atmosphere storage (MA), which refers to the regulation of O by respiration of fruits and vegetables, and controlled atmosphere storage (CA)₂And CO₂The content of the active carbon is a storage mode, and CA refers to the condition that the gas proportion of the storage environment of fruits and vegetables is changed artificially, and generally CO is increased₂Concentration with simultaneous reduction of O₂The concentration is used for inhibiting the respiration of the fruits, thereby achieving the aim of keeping fresh. Song square circle, etc. by CO₂:O₂:N₂Air-packing at partial pressure ratio of 3:15:82, 7:25:68, 11:35:54, storing fresh fructus Lycii in refrigerator at 0, 1, 2 deg.C for 24 d, and testing to show 7% CO at 0, 1 deg.C₂+25%O₂+68%N₂The packaging can effectively prolong the storage period of fresh medlar and keep the fruit quality. In addition, the packaging material also has influence on the modified atmosphere preservation effect, for example, in the research of Wang Rui Qing and the like, the PEF-MAP (polyethylene film modified atmosphere) and SGF-MAP (silicon window film modified atmosphere) effects are found in the short term (21 d)And when the PEF-MAP is stored for a long time (35 d), the PEF-MAP has the best packaging effect and the lowest rotting rate. The existing research shows that the research on the packaging material for the controlled atmosphere storage of fresh medlar is single, and the exploration of the controlled atmosphere parameter conditions is not thorough.

1-MCP (1-methylcyclopropene) at a low concentration can inhibit the generation of ethylene by inhibiting an ethylene receptor which can weaken the physiological effect of ethylene by preferentially binding with it, and has no residue after treatment, and has been widely used in production. The Wang Rui Qing et al selects 1-MCP with the volume fraction of 1 mL/L to treat fresh wolfberry fruits for 20 hours at the temperature of 2 ℃, and storage experiment results show that the 1-MCP treatment can obviously reduce the rot rate of the fruits at the later storage period, so that the storage period of the fresh wolfberry fruits is prolonged, but the content of soluble solid matters, the content of titratable acid and the appearance of the fresh wolfberry fruits are not obviously influenced on the whole. In terms of the current research progress, the application research of the 1-MCP in the storage and preservation of fresh medlar fruits is less, and the parameters such as the application mode, dosage and the like of the 1-MCP are still to be widely researched. The low-temperature preservation is to weaken the respiration of fruits, inhibit the life activities of microorganisms and reduce the biological activity of enzymes by reducing the storage environment temperature, so that the nutritional ingredients and the freshness of the fruits can be kept, and the purpose of preservation is achieved. The influence of low-temperature and normal-temperature storage on the preservation effect of the stemmed lycium barbarum is studied, and the results show that the low temperature obviously reduces the weight loss rate and the rotting rate of the harvested stemmed lycium barbarum during the storage period, the quality of the fruits is effectively maintained, and the storage period of the fruits at the low temperature of 4 ℃ can be prolonged to 6 days. The research of Zhao Youli et al shows that the respiration intensity, the relative permeability of cell membrane and the water loss rate of the medlar fruits treated at low temperature (1 ℃, 8 ℃) are obviously lower than those of the medlar fruits treated at high temperature (20 ℃), V_CThe mass ratio of the soluble solid to the soluble solid is obviously higher than that of the soluble solid treated at high temperature (20 ℃), the respiratory peak is delayed after low-temperature treatment, the nutrient content is reduced more slowly, and the effect of low-temperature storage at 1 ℃ is more obvious.

The patent is based on the biological characteristics of the medlar, and is established on the basis of taking a portable preservation box which can be operated in a commercial way as a carrier, combining with the treatment of a nutritional preservative before collection, combining with various preservation technologies such as artificial modified atmosphere combined with modified atmosphere, physiological regulation, preservative preservation, precise temperature control and the like in the transportation and storage stages, establishing a novel method for preserving the medlar, which prolongs the seamless whole-course cold chain of fresh medlar collection, transportation and storage, and promotes the development of the fresh medlar in the field of preservation and preservation.

Disclosure of Invention

The invention aims to fill up the blank of the previous research and provides a method for prolonging the preservation period of fresh-eating medlar. The invention provides a novel wolfberry preservation method for prolonging seamless whole-course cold chain of fresh food wolfberry collection, transportation and storage, which is established by taking a portable preservation box capable of being operated in a commercial way as a carrier and combining with various preservation technologies such as pre-harvest nutrition preservative treatment, modified atmosphere in transportation, artificial modified atmosphere combined with modified atmosphere in the storage stage, physiological regulation and preservation, precise temperature control and the like, and promotes the development of fresh food wolfberry in the field of storage and preservation.

In order to achieve the purpose, the invention discloses the following technical contents:

the invention discloses a fresh-keeping process for prolonging fresh eating of medlar, which comprises the following steps:

step 1: the method comprises the steps of preparing a nutritional preservative consisting of 1-methylcyclopropene, marine fish protein peptide and epsilon-polylysine before harvesting, putting the prepared nutritional preservative into a sprayer, manually spraying the nutritional preservative (10-30 mL per kg of fruits), and uniformly spraying the nutritional preservative on the surface of the Chinese wolfberry to be picked.

Step 2: and after the surfaces of the Chinese wolfberry are dry, picking the Chinese wolfberry completely, putting the Chinese wolfberry into a portable air conditioning box, adding an ice box in the middle of the air conditioning box before buckling a cover, then buckling the cover for loading, ensuring that the Chinese wolfberry is transported to a destination within 12-16 h, and timely putting the Chinese wolfberry into a refrigeration house to open the cover of the air conditioning box for precooling.

And step 3: and (3) fully precooling the medlar, adding a terahertz freshness protection package and a 1-MCP freshness protection package, adding a proper amount of dry ice, immediately covering, and entering a storage stage.

The invention discloses a nutrient preservative which comprises 0.8-1.2 g/L of 1-methylcyclopropene subjected to alpha-cyclodextrin and chitosan curing treatment, 4-6 g/L of marine fish protein peptide and 1.0-2.0 g/L of epsilon-polylysine.

The invention discloses a portable air conditioning box made of food-grade transparent plastic, and the design and the principle are disclosed in an invention patent 2015101651019.

The invention discloses a portable air-conditioning box for carrying medlar with the mass of 2.0-2.5 kg and the logistics time of transporting the medlar to a destination within 12-16 h, wherein CO is contained in the box body₂The content is 5-20%.

The invention discloses a method for pre-cooling a medlar-containing air-conditioned box, which is used for timely entering a cold storage to open a box cover for pre-cooling when the medlar-containing air-conditioned box reaches a destination, wherein the temperature of the cold storage is-0.5 ℃, and the pre-cooling time is 18-24 hours.

The invention discloses an anti-aging terahertz freshness-retaining bag with an anti-aging effect, wherein 1 bag of terahertz freshness-retaining bag is added into every 1.0 kg of medlar, 1 bag of 1-MCP freshness-retaining bag is added into every 2.5 kg of medlar, the amount of dry ice is 2-3 g, and a box body is filled with CO₂The content is controlled to be 6-8%. .

The invention discloses a storage stage, wherein the temperature in the air conditioning box body is controlled to be-0.3 ℃, and CO is controlled₂The content is maintained at 8-12%, O₂The content is maintained at 5-10%.

The invention further discloses application of the method for prolonging the freshness date of the fresh-eaten medlar in prolonging the freshness date of the medlar, delaying the softening and mildew phenomena of fruits during storage, avoiding the problems of medlar frost loss, reduced storage performance and the like caused by multiple times of hands falling after picking the medlar, forming a novel seamless whole-process cold chain integrated medlar freshness-keeping mode in a medlar picking and storage link, and prolonging the freshness date of the medlar to more than 50 d.

The invention mainly solves the problem of short preservation period after medlar picking, mainly inspects the influence of the pre-picking nutrition preservative, the modified atmosphere in transportation, the combination of the artificial modified atmosphere in the storage stage and the modified atmosphere, the physiological regulation and the preservative preservation method on the preservation effect of the fresh medlar, and has the main difficulty in determining the technological parameters of the pre-picking nutrition preservative, the modified atmosphere in transportation, the combination of the artificial modified atmosphere in the storage stage and the modified atmosphere, the physiological regulation and the preservative preservation.

Compared with the prior art, the method for prolonging the fresh-keeping period of the fresh-eating medlar has the positive effects that:

(1) firstly, the research of fresh eating medlar in the field of storage and preservation in China is relatively less, most of the fresh eating medlar is in the research stage of laboratories, and the commercial operation is poor. Aiming at the biological characteristics of fresh medlar, a commercially operated air-conditioning box is used as a carrier, and a novel medlar fresh-keeping method with seamless whole-process cold chain for medlar collection and storage is established by adopting a plurality of fresh-keeping technologies such as pre-collection nutrition preservative treatment, modified atmosphere during transportation, artificial modified atmosphere combined with modified atmosphere, physiological regulation, preservative fresh-keeping, precise temperature control and the like in the storage stage, so that the development of medlar in the field of storage and fresh-keeping can be promoted, the fresh-keeping period can be obviously prolonged, the softening and the decay of fruits are inhibited, and the leaves of medlar are fresh green.

(2) In addition, based on the atmosphere control box in blueberry, red bayberry, indigo honeysuckle and lily have been reported, the difference of the patent from the fruit preservation method is that the formula of the nutritional preservative before picking, the atmosphere control in transportation and the use of a novel terahertz preservative bag are adopted in the storage stage, in addition, the 1-MCP function is not only reflected in the function of the medlar fruits, but also on the green protection of leaves, the use, commercial operation and advanced preservation technology are integrated into the method, and the method for prolonging the preservation period of the fresh medlar is established based on the biological characteristics of the medlar, and the process parameters and steps are obviously different from the prior literature or patent, and have uniqueness.

Detailed Description

The invention is described below by means of specific embodiments. Unless otherwise specified, the technical means used in the present invention are well known to those skilled in the art. In addition, the embodiments should be considered illustrative, and not restrictive, of the scope of the invention, which is defined solely by the claims. It will be apparent to those skilled in the art that various changes or modifications to the nutritional preservative formulation, to the modified atmosphere during transportation, to the modified atmosphere during storage, and to the gas composition and temperature range within the self-generating atmosphere and enclosure of these embodiments are within the scope of the invention without departing from the spirit and scope of the invention. The raw materials and reagents used in the present invention are commercially available. Wherein, the air-conditioning box, the terahertz fresh-keeping bag, the 1-MCP fresh-keeping bag and the like are all sold in the market.

Example 1

Uniformly spraying different nutritional preservatives on the surfaces of the Chinese wolfberries before picking, picking 2.0 kg of the well-picked Chinese wolfberries after the surfaces of the Chinese wolfberries are dry next day, putting the Chinese wolfberries into a portable air conditioning box, adding an ice box in the middle of the air conditioning box before covering, covering and loading, transporting to a destination within 12 h, timely putting the Chinese wolfberries into a refrigeration house at (-0.5 ℃) to open the cover of the air conditioning box for precooling for 20 h, and covering and storing. Comprises the following steps:

(1) before picking, the nutrient preservative is not used for treatment, and the nutrient preservative is recorded as CK;

(2) the formula of the nutritional preservative is 0.5 g/L1-methylcyclopropene, 5 g/L marine fish protein peptide and 1.5 g/L epsilon-polylysine, and the formula is marked as the nutritional preservative 1;

(3) the formula of the nutritional preservative is 0.8 g/L1-methylcyclopropene, 5 g/L marine fish protein peptide and 1.5 g/L epsilon-polylysine, and the formula is marked as a nutritional preservative 2;

(4) the formula of the nutritional preservative is 0.8 g/L of 1-methylcyclopropene, 2 g/L of marine fish protein peptide and 1.5 g/L of epsilon-polylysine, and the formula is marked as a nutritional preservative 3;

(5) the formula of the nutritional preservative is 0.8 g/L1-methylcyclopropene, 5 g/L marine fish protein peptide and 0.5 g/L epsilon-polylysine, and the nutritional preservative is marked as nutritional preservative 4.

Table 1 shows the influence of different nutritional preservatives on the rotting rate and the soft fruit rate of the medlar, and as can be seen from Table 1, the rotting rate and the soft fruit rate of the medlar treated differently show a rising trend along with the prolonging of the storage period, wherein the rotting rate and the soft fruit rate of CK are higher than those of different nutritional preservative treatment groups, and the pretreatment has a certain preservation effect. By comparing the nutrition preservative 1 and the nutrition preservative, 0.8 g/L of 1-methylcyclopropene is better than 0.5 g/L, similarly, by comparing other treatments, 5 g/L of marine fish protein peptide is better than 2 g/L, 1.5 g/L of epsilon-polylysine is better than 0.5 g/L, and the nutrition preservative 3 (0.8 g/L of 1-methylcyclopropene, 5 g/L of marine fish protein peptide and 1.5 g/L of epsilon-polylysine) has the best preservation effect on the medlar.

TABLE 1 influence of different nutritive antistaling agents on rotten rate and soft fruit rate of Chinese wolfberry

Example 2

Uniformly spraying nutritional preservatives (0.8 g/L1-methylcyclopropene, 5 g/L marine fish protein peptide and 1.5 g/L epsilon-polylysine) on the surface of the Chinese wolfberry before picking, picking 2.0 kg of the well-picked Chinese wolfberry after the surface of the Chinese wolfberry is dry the next day, putting the Chinese wolfberry into a portable air-conditioned box, adding an ice box in the middle of the air-conditioned box before covering, covering and loading, transporting to a destination within 12 h, opening the cover of the air-conditioned box in a refrigeration house at (-0.5 ℃) in time for precooling for 20 h, adding dry ice, immediately covering, and entering a storage stage. Comprises the following steps: (1) placing into an air conditioning box without buckling a cover, and recording as CK; (2) placing the container into an air conditioning box without a dry ice cover, and recording as mMAP; (3) put into an air-conditioning box, and 3 g of dry ice is added to cover the box, and the mark is CA + mMAP.

Table 2 shows the effect of different modified atmosphere treatments on the rotting rate and the fruit softening rate of the medlar, and from Table 2, the rotting rate of the medlar in the CK group without modified atmosphere treatment reaches 32.45% when the medlar is stored for 50 days, and the fruit softening rate is close to 50%, while the rotting rate and the fruit softening rate of the medlar during storage can be obviously reduced by modified atmosphere treatment. Comparing different modified atmosphere treatments, the modified atmosphere method has the best effect of controlling the softening and the decay of the medlar by combining artificial modified atmosphere with modified atmosphere (CA + mMAP), and shows that the modified atmosphere method is more beneficial to the preservation of the medlar.

TABLE 2 Effect of different modified atmosphere treatments on rotting and softening rates of Lycium barbarum

Example 3

Uniformly spraying a nutritional preservative (0.8 g/L1-methylcyclopropene, 5 g/L marine fish protein peptide and 1.5 g/L epsilon-polylysine) on the surface of the Chinese wolfberry before picking, picking 2.0 kg of the well-picked Chinese wolfberry after the surface of the Chinese wolfberry is dry the next day, putting the Chinese wolfberry into a portable air-conditioning box, adding an ice box in the middle of the air-conditioning box before covering, covering and loading, transporting to a destination within 12 h, timely putting the Chinese wolfberry into a refrigeration house at (-0.5 ℃) to pre-cool for 20 h, adding a terahertz preservative bag and a 1-MCP preservative bag, adding 3 g of dry ice, immediately covering and entering a storage stage. Comprises the following steps: (1) the preservation bag is not put in and is recorded as CK; (2) putting the fresh-keeping bag into a 1-MCP and recording the fresh-keeping bag as 1-MCP; (3) and putting the 1-MCP fresh-keeping package and the terahertz fresh-keeping package into the container, and recording the bag as 1-MCP + THZ.

Table 3 shows the influence of 1-MCP combined with terahertz treatment on the rotting rate and soft fruit rate of the lycium barbarum, and it can be seen from table 3 that 1-MCP treatment after harvesting has a certain effect on the fresh-keeping of the lycium barbarum, 1-MCP combined with terahertz treatment has a synergistic effect, and the rotting rate and the soft fruit rate of the lycium barbarum are both less than 10% when stored for 50 days, so that the lycium barbarum has good marketability.

TABLE 31 influence of terahertz treatment in combination with MCP on rotting and soft fruit rate of Lycium barbarum

Table 4 comparison of the effect of the preservation method of this patent in lycium barbarum with the existing preservation method

When the preservation method of the patent is adopted to store the medlar, the fruit rotting rate is lower than 10% after 50 days of storage, the freshness is good, the storage period of the medlar in the existing preservation method is only 30 days, and the medlar preservation method of the patent can inhibit the rotting in the storage period and prolong the storage period.