CN106283838A - A kind of 1 methyl cyclopropene tin foil and preparation method thereof - Google Patents

Abstract

The invention discloses a kind of 1 methyl cyclopropene tin foil, this tin foil is made up of original paper layer and the fresh-keeping layer being coated on its surface, and original paper layer is mainly mixed by bamboo pulp and hardwood pulp copies system；Fresh-keeping layer be mainly composed of 1 methyl cyclopropene inclusion complex, Polyethylene Glycol PUR, water absorbing agent, dispersant and slow releasing agent.The invention also discloses the preparation method of 1 methyl cyclopropene tin foil, step includes the preparation of 1 methyl cyclopropene inclusion complex, the preparation of coating, the preparation of original paper layer, is coated with and is dried.The 1 methyl cyclopropene tin foil good refreshing effect of the present invention, Environmental compatibility is good, easy to use, effect stability, all has good applicability in storage and transportation.

Description

A kind of 1-methylcyclopropene fresh-keeping paper and preparation method thereof

technical field

The invention belongs to the field of special paper, and in particular relates to a 1-methylcyclopropene fresh-keeping paper and a preparation method thereof.

Background technique

With the improvement of the quality of life, people have a higher consumption demand for seasonal and fresh fruits and vegetables. my country's fruit planting area and fruit output have always ranked first in the world, but fruit and vegetable products have high moisture content and are easy to rot. At this stage, my country's fresh fruits and vegetables are due to improper harvesting, backward post-harvest commercial processing technology, improper storage and transportation conditions, and storage and processing capabilities. Insufficient and other reasons, the rot loss rate caused by fruit has reached 30%, vegetables have reached 30-40%, while the loss rate in developed countries is less than 7%. Therefore, it is very important to adopt effective fresh-keeping technology and materials, inhibit the life activities of fruits and vegetables, reduce their metabolism level, prolong their storage time, and maintain good commodity quality.

It is well known that ethylene can cause premature death of plants or plant parts (including, for example, flowers, leaves, fruits) and vegetables by binding to certain receptors in plants. Ethylene also promotes yellowing of leaves and shrinkage of growing ginger, as well as premature abscission of fruits, flowers and leaves. Because of these problems caused by ethylene, a great deal of research is currently focused on methods of preventing or reducing the harmful effects of ethylene on plants.

In recent years, researchers have discovered that 1-methylcyclopropene (1-MCP) is a very effective ethylene receptor inhibitor. It can irreversibly act on ethylene receptors by preferentially binding to ethylene receptors, preventing the binding of endogenous ethylene and exogenous ethylene to ethylene receptors, thereby inhibiting the post-ripening or A series of physiological and biochemical reactions of aging. It has the characteristics of safety, non-toxicity, low use cost, less dosage, no residue, convenient use, long fresh-keeping period and obvious effect of inhibiting ethylene. However, a major problem with such compounds is that they are typically unstable gases that present a risk of explosion when compressed. In order to stabilize the reactivity of cyclopropenes and thereby provide convenient and safe methods for storage, transport and application or delivery of these reactive compounds to plants, one approach to the above problem is to incorporate cyclopropenes into molecular encapsulating agents complexing in things.

The first company to produce 1-MCP was Rohm and Haas, whose trade name was Ethyblock, which was mainly adsorbed by cyclodextrin. Taiwan Litong Company adopts unique micro-embedding technology to produce 1-methylcyclopropene, the trade name is Anxipei. At present, the manufacturers reported in China include Lanzhou Jiacheng Biotechnology Company (tablet) and Shandong Nutrient Source Food Technology Co., Ltd. (1-MCP solution).

At present, tablet 1-MCP and liquid 1-MCP both at home and abroad have good fresh-keeping effects, but there are still problems such as inconvenient use, difficult operation and instability. 1-MCP tablets need airtight conditions and airtight fumigation for 6-12 hours in the application process, the operation is complicated, and it is not easy to store quickly on a large scale; liquid 1-MCP has poor stability at room temperature, and it needs to be stored at low temperature to ensure 1-MCP stability.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention provides a 1-methylcyclopropene fresh-keeping paper which is applied to the storage and preservation of fruits and vegetables, is convenient to use, stable in effect and easier to popularize and apply, and a preparation method thereof.

The technical scheme adopted by the present invention to solve its technical problems is: a kind of 1-methylcyclopropene fresh-keeping paper, comprising a base paper layer and a fresh-keeping layer coated on the surface of the base paper layer; the base paper layer is mixed with bamboo pulp and hardwood pulp Manufactured, the quantitative of the base paper layer is 120-150g/m ² ; the fresh-keeping layer includes 1-methylcyclopropene inclusion, polyethylene glycol hot-melt adhesive, water absorbing agent, dispersant and slow-release agent, and the fresh-keeping layer The quantitative is 15-40g/m ² .

When 1-methylcyclopropene fresh-keeping paper is added to fruit or vegetable cartons or containers, the water vapor and carbon dioxide produced by the respiration of fruits and vegetables will induce the slow-controlled release of 1-methylcyclopropene (1-MCP) into the container from the fresh-keeping paper coating. ), and 1-MCP is an ethylene blocker, which can inhibit the production of ethylene in fruits and vegetables, delay the ripening of fruits and vegetables, and prolong the shelf life and storage period of packaged fruits and vegetables. But before the fruits and vegetables are loaded, the moisture in the air is not enough to cause the release of 1-MCP, and the fresh-keeping function of the fresh-keeping paper will not be activated.

The present invention also discloses a preparation method of the above-mentioned 1-methylcyclopropene fresh-keeping paper, comprising the following steps:

1) Preparation of 1-methylcyclopropene inclusion complex: Introduce 1-methylcyclopropene gas into 5-15% modified amylose solution, adjust pH=4.5-5.0 and temperature 5-10°C, and precipitate Starch crystals encapsulating 1-methylcyclopropene, controlling the mass percentage of 1-methylcyclopropene in the 1-methylcyclopropene inclusion complex to be 0.10-0.16%;

2) Preparation of paint: Weigh 100 parts of starch crystals obtained in step 1), and weigh 8-15 parts of water-absorbing agent, 5-10 parts of dispersant, 5-10 parts of slow-release agent, add polyethylene glycol In the hot melt adhesive, stir and disperse at 500-1000r/min, and set aside;

3) Preparation of base paper layer: The raw materials with bamboo pulp and hardwood as the main components are disintegrated, wherein the mass ratio of bamboo pulp and hardwood is 5-10:3, mixed and refined, screened to make pulp, and made into ^A base paper layer with a basis weight of 120-150g/m2;

4) Coating: the coating obtained in step 2) is coated on the base paper layer surface obtained in step 3) in a papermaking coating mode, forming a fresh-keeping layer with a quantitative quantity of 15-40g/m ² ;

5) Drying: drying the coated paper obtained in step 4) at a temperature of 40-60° C. for 2-5 hours to obtain.

Further, the preparation method of the modified amylose in the step 1) is as follows: first use α-amylase to degrade the amylose, control the degree of polymerization to 100-200, and then pass 2,3-epoxypropyl tri Methylammonium chloride substitution reaction, the degree of substitution is controlled to be 0.1-0.5.

Further, the average molecular weight of the polyethylene glycol hot melt adhesive in the step 2) is 4000.

Further, the freeness during beating in the step 3) is controlled at 275-350ml.

Further, in the step 3), the paper pulp is formed by using a three-layer wire paper machine, pressed by a large mechanical roller, dried, and super-calendered to form a base paper layer.

Aiming at the problems existing in the application of 1-MCP compounds, the present invention further develops a new type of 1-MCP fresh-keeping paper on the basis of the research of 1-MCP molecular wrapping technology, which is applied to the storage and fresh-keeping of fruits and vegetables, which is convenient to use and has excellent fresh-keeping effect. Good, stable fresh-keeping effect, good environmental compatibility, good applicability in storage and transportation, and easier to popularize and apply.

The beneficial effects of the present invention are: (1) The wet forming and coating production process of traditional papermaking is adopted, which has the characteristics of simple process flow, easy control of product quality, and environmental protection in the production process, and the produced materials can be accurately produced (2) the use of cyclopropylene fresh-keeping paper is simpler and more convenient, and it is easy to be popularized and applied on a large scale; (3) the present invention utilizes a small amount of water extracted from moist air, or the water released by fruit self-breathing water, triggering the slow release of 1-MCP, so that the preservation effect is more superior; (4) the present invention will allow the user to treat the fruit with cyclopropene gas directly in the shipping container, rather than in a huge processing container, box or room. or vegetables for processing.

detailed description

In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than Full examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

Example 1

Step 1: degrade amylose by a-amylase, control the degree of polymerization at 100, and then undergo substitution reaction with 2,3-epoxypropyltrimethylammonium chloride, control the degree of substitution to 0.1 to obtain modified amylose .

Step 2, preparation of 1-methylcyclopropene inclusion complex: pass 1-MCP gas into the 8% modified amylose solution obtained in step 1, adjust pH=4 and temperature 5°C, and precipitate 1 -Starch crystals of MCP, the mass percentage of 1-MCP in the inclusion complex is controlled to be 0.10%.

Step 3, preparation of coating: Weigh 100 parts of starch crystals obtained in step 2, and weigh 8 parts of water-absorbing agent, 5 parts of dispersant, and 5 parts of slow-release agent, add polyethylene glycol with an average molecular weight of 4000, and heat In the melt, stir and disperse at 800r/min, and put it into the paint storage barrel for later use.

Step 4, preparation of base paper layer: take bamboo pulp and hardwood with a mass ratio of 5:3 as the main raw materials to make paper pulp through crushing, mixing and refining, and screening, wherein the Canadian freeness is controlled at 350ml, and papermaking is made with a three-layer net It is formed by machine copying, squeezed by a large mechanical roller, dried, and super calendered to make a base paper layer with a weight of 120g/ ^m2 .

Step 5, coating: the coating obtained in step 3 is coated on the surface of the base paper layer obtained in step 4 in a papermaking coating manner, forming a fresh-keeping layer with a weight of 15 g/m ² .

Step 6, drying: the coated paper obtained in step 5 is vacuum-dried at a low temperature at a temperature of 40° C. for 2 hours to obtain the finished 1-methylcyclopropene fresh-keeping paper (a).

Example 2

Step 1: degrade amylose by a-amylase, control the degree of polymerization at 150, and then undergo substitution reaction with 2,3-epoxypropyltrimethylammonium chloride, control the degree of substitution to 0.3 to obtain modified amylose .

Step 2, preparation of 1-methylcyclopropene inclusion complex: 1-MCP gas is passed into the 10% modified amylose solution obtained in step 1, and the pH is adjusted to 4.5 and the temperature is 10°C, and the encapsulation 1 -MCP starch crystals, the mass percentage of 1-MCP in the inclusion complex is controlled to be 0.12%.

Step 3, preparation of coating: Weigh 100 parts of starch crystals obtained in step 2, and weigh 10 parts of water-absorbing agent, 8 parts of dispersant, and 8 parts of slow-release agent, add polyethylene glycol with an average molecular weight of 4000, and heat In the melt glue, stir and disperse at 900r/min, and put it into the paint storage barrel for later use.

Step 4, preparation of base paper layer: take bamboo pulp and broad-leaved wood with a mass ratio of 8:3 as the main raw materials to make paper pulp through crushing, mixing and refining, and screening, wherein the Canadian freeness is controlled at 320ml, and papermaking is made with a three-layer net It is formed by machine copying, squeezed by a large mechanical roller, dried, and super calendered to make a base paper layer with a weight of 130g/ ^m2 .

Step 5, coating: the coating obtained in step 3 is coated on the surface of the base paper layer obtained in step 4 by means of papermaking coating, forming a fresh-keeping layer with a weight of 25 g/m ² .

Step 6, drying: vacuum-dry the coated paper obtained in Step 5 at a temperature of 50° C. for 3 hours to obtain the finished 1-methylcyclopropene fresh-keeping paper (b).

Example 3

Step 1: degrade amylose by a-amylase, control the degree of polymerization at 200, and then undergo substitution reaction with 2,3-epoxypropyltrimethylammonium chloride, control the degree of substitution to 0.5 to obtain modified amylose .

Step 2, preparation of 1-methylcyclopropene inclusion complex: 1-MCP gas is passed into the 12% modified amylose solution obtained in step 1, and the pH is adjusted to 5.0 and the temperature is 10°C, and the encapsulation 1 -Starch crystals of MCP, the mass percentage of 1-MCP in the inclusion complex is controlled to be 0.16%.

Step 3, preparation of coating: Weigh 100 parts of starch crystals obtained in step 2, and weigh 15 parts of water-absorbing agent, 10 parts of dispersant, and 10 parts of slow-release agent, add polyethylene glycol with an average molecular weight of 4000, and heat In the melt, stir and disperse at 700r/min, and put it into the paint storage bucket for later use.

Step 4, preparation of base paper layer: take bamboo pulp and broad-leaved wood with a mass ratio of 9:3 as the main raw materials to make paper pulp through crushing, mixing and refining, and screening, wherein the Canadian freeness is controlled at 275ml, and papermaking is made with a three-layer net It is formed by machine copying, squeezed by a large mechanical roller, dried, and super calendered to make a base paper layer with a weight of 150g/ ^m2 .

Step 5, coating: the coating obtained in step 3 is coated on the surface of the base paper layer obtained in step 4 in a papermaking coating manner, forming a fresh-keeping layer with a weight of 40 g/m ² .

Step 6, drying: vacuum-dry the coated paper obtained in Step 5 at a temperature of 60° C. for 5 hours to obtain the finished 1-methylcyclopropene fresh-keeping paper (c).

Experiments show that, taking the blank group as a control, when 1-methylcyclopropene fresh-keeping paper is added to fruit or vegetable cartons or containers, the water vapor and carbon dioxide produced by the respiration of fruits and vegetables will induce the slow-controlled release of the fresh-keeping paper coating into the container. 1-MCP, and 1-MCP is an ethylene blocker, which can inhibit the production of ethylene in fruits and vegetables, delay the ripening of fruits and vegetables, and prolong the shelf life and storage period of packaged fruits and vegetables. Before the fruits and vegetables are loaded, the moisture in the air is not enough to cause the release of 1-MCP, and the fresh-keeping function of the fresh-keeping paper will not be activated.

Detect the fresh-keeping effect of the 1-methylcyclopropene fresh-keeping paper built-in processed fruit obtained in Example 1, Example 2 and Example 3 of the present invention.

Eight mature Fenghua peaches harvested on the same day were put into cartons, and the preservation effect was evaluated according to the evaluation indicators of fruit color, hardness, weight loss and other commodity rates at room temperature for 7 days, as shown in Table 1.

Table 1

The results show that the commodity rates of Fenghua peaches treated with the fresh-keeping papers of Example 1, Example 2 and Example 3 of the present invention are 80%, 85% and 92% respectively. The edible rate of Fenghua peaches in the blank group was only 50%. The test results show that the 1-methylcyclopropene fresh-keeping paper of the present invention has a good fresh-keeping effect on fruits.

The above specific embodiments are used to explain the present invention, rather than to limit the present invention. Within the spirit of the present invention and the protection scope of the claims, any modification and change made to the present invention will fall into the protection scope of the present invention.

Claims (6)

1. a 1-methyl cyclopropene tin foil, it is characterised in that: include original paper layer and be coated on the fresh-keeping layer on original paper layer surface； Described original paper layer is mixed by bamboo pulp and hardwood pulp copies system, the quantification of 120-150g/m of original paper layer²；Described fresh-keeping layer includes 1- Methyl cyclopropene inclusion complex, Polyethylene Glycol PUR, water absorbing agent, dispersant and slow releasing agent, the quantification of 15-40g/ of fresh-keeping layer m²。

2. the preparation method of a 1-methyl cyclopropene tin foil as claimed in claim 1, it is characterised in that include following step Rapid:

1) preparation of 1-methyl cyclopropene inclusion complex: the modified amylose that 1-methylcyclopropene gas is passed through 5-15% is molten Liquid, regulation pH=4.5-5.0 and temperature 5-10 DEG C, separate out the starch crystal of parcel 1-methyl cyclopropene, control 1-methyl ring third 1-methyl cyclopropene mass percent in alkene inclusion complex is 0.10-0.16%；

2) preparation of coating: weigh step 1) in obtained by 100 parts of starch crystal, and weigh water absorbing agent 8-15 part, dispersant 5-10 part, slow releasing agent 5-10 part, add in Polyethylene Glycol PUR, through 500-1000r/min dispersed with stirring, standby；

3) preparation of original paper layer: by the raw material as main component with bamboo pulp and leaf wood through size degradation, wherein bamboo pulp and leaf wood Mass ratio is 5-10:3, mixes defibrination, and screening is made paper pulp, made quantification of 120-150g/m²Original paper layer；

4) coating: claim step 2) in obtained by coating be coated on step 3 in papermaking coating mode) in the original paper layer table of gained Face, forms quantification of 15-40g/m²Fresh-keeping layer；

5) be dried: by step 4) in obtained by coating paper the temperature of 40-60 DEG C, be dried 2-5 hour, to obtain final product.

The preparation method of 1-methyl cyclopropene tin foil the most according to claim 2, it is characterised in that described step 1) in The preparation method of modified amylose is: being degraded by amylose first with a-amylase, the control degree of polymerization is 100-200, then Through 2,3-epoxypropyltrimethylchloride chloride substitution reaction, control substitution value is 0.1-0.5.

The preparation method of 1-methyl cyclopropene tin foil the most according to claim 2, it is characterised in that: described step 2) in The mean molecule quantity of Polyethylene Glycol PUR is 4000.

The preparation method of 1-methyl cyclopropene tin foil the most according to claim 2, it is characterised in that: described step 3) in Freedom during making beating controls at 275-350ml.

The preparation method of 1-methyl cyclopropene tin foil the most according to claim 2, it is characterised in that: described step 3) in Paper pulp three-layer network paper machine is copied and makes shape, through machinery press with large-roll-diameter, drying, supercalendering, manufacture paper with pulp into original paper layer.