阅读说明：本技术 一种蔬果保鲜方法 (Vegetable and fruit fresh-keeping method ) 是由 尹恒 王文霞 于 2019-03-05 设计创作，主要内容包括：本发明公开了一种蔬果保鲜方法,该方法是在蔬果采收后使用海藻酸钠寡糖溶液处理,所用海藻酸钠寡糖的质量浓度为0.05-0.5g/L,M/G为5/5到7/3,平均分子量为500-2000Da。该方法可显著延长采摘后蔬果在常温和低温贮存条件下的货架期。同时对果蔬的品质还有改善的作用。本发明所提供的蔬果保鲜方法,对于处理后的蔬果无环境污染,对人体无健康危害,对环境友好,可广泛应用于各种蔬果,具有施用方法简单、易于推广应用等优点。(The invention discloses a vegetable and fruit fresh-keeping method, which is characterized in that after the vegetable and fruit are harvested, sodium alginate oligosaccharide solution is used for processing, the mass concentration of the used sodium alginate oligosaccharide is 0.05-0.5G/L, the M/G is 5/5-7/3, and the average molecular weight is 500-2000 Da. The method can remarkably prolong shelf life of picked vegetable and fruit under normal temperature and low temperature storage conditions. Meanwhile, the fruit and vegetable quality is improved. The vegetable and fruit fresh-keeping method provided by the invention has no environmental pollution to the treated vegetable and fruit, has no health hazard to human bodies, is environment-friendly, can be widely applied to various vegetables and fruits, and has the advantages of simple application method, easy popularization and application and the like.)

1. A method for preserving vegetables and fruits is characterized in that the storage period of the vegetables and fruits can be prolonged by processing the vegetables and fruits with sodium alginate oligosaccharide aqueous solution after the vegetables and fruits are harvested.

2. The method as claimed in claim 1, wherein the aqueous solution of alginate-derived oligosaccharide has a mass concentration of 0.05-0.5G/L, a M/G value of 5/5-7/3, and an average molecular weight of 500-2000 Da.

3. The method as claimed in claim 1, wherein the mass concentration of the alginate oligosaccharide in the applied sodium alginate solution is 0.05-0.2G/L, the M/G value is 7/3, and the average molecular weight is 600-1000 Da.

4. The method for preserving vegetables and fruits according to any one of claims 1-3, wherein the vegetables and fruits are soaked for 1-5min after being picked at the mature period, and then naturally dried.

5. The method for preserving vegetables and fruits according to claim 1, wherein the method comprises the following steps: the vegetable and fruit fresh-keeping method has obvious fresh-keeping effect on the vegetables and fruits which are not subjected to respiratory leap type.

Technical Field

The invention relates to a method for preserving vegetables and fruits, in particular to a method for preserving vegetables and fruits by using sodium alginate oligosaccharide solution for treatment after the vegetables and fruits are harvested.

Background

Vegetables and fruits are one of the indispensable foods in daily life of people and are important nutrient sources for human beings. China is a big country for fruit and vegetable production and consumption, and the planting area and the total yield all account for the first place in the world. Wherein the annual yield of fruits is about 6 million tons, and the yield of vegetables reaches 4.4 hundred million tons. However, because of the strong seasonality and regional nature of the fruit and vegetable production and the perishable nature of the fruit and vegetable, the existing preservation technology adopted in a series of processes such as storage, transportation, selling and the like is not complete, the fruit and vegetable in China is rotted and deteriorated to cause the loss amount to reach 25% -30% every year, the economic loss is hundreds of millions of yuan, and the loss amount in developed countries is about 5%, which is only 1/5 in China. At present, how to effectively improve the fruit and vegetable storage and preservation technology to reduce the postharvest loss becomes a scientific and technological problem to be solved urgently in China, and the research on a natural, efficient, safe and nontoxic fruit preservation method has very important significance.

At present, the main fresh-keeping technologies in the fruit and vegetable industry comprise a physical fresh-keeping technology, a chemical fresh-keeping technology and a biological fresh-keeping technology. The physical preservation technology mainly aims at creating a low-temperature high-humidity environment and effectively inhibiting the postharvest respiration and the water evaporation process of fruits and vegetables; the chemical fresh-keeping technology mainly uses a bactericide in the process of storing the fruits and the vegetables, and effectively prevents microorganisms from entering the fruits and the vegetables from the damaged parts of the fruits and the vegetables. The biological preservation technology is mainly applied to the air-conditioned storage technology, the film-coating preservation technology and the ethylene path blocking technology at present, and the first two technologies achieve the preservation effect by inhibiting the gas exchange between the fruits and the vegetables and the outside. The air conditioning technology is realized by changing the gas proportion in the storage environment, and the coating preservation technology is to artificially add a layer of film on the surface of the fruits and vegetables to inhibit the respiration and water evaporation of the fruits and vegetables. The ethylene blocking type preservative inhibits the after-ripening and aging process of the fruits and vegetables regulated by the ethylene way by inhibiting the ethylene generated by the fruits and vegetables, thereby greatly prolonging the storage period of the fruits and vegetables and effectively reducing the rot of the fruits and vegetables.

Although the physical preservation technology is safe, a large amount of energy is consumed, the cost is high, and the operation is complex, so the practical application of the technology is greatly limited. The chemical treatment method mainly takes bactericide treatment as a main treatment at present, has simple treatment operation and certain efficacy, but adopts the bactericide treatment along with a series of problems of affecting the health of consumers, polluting the environment, generating drug resistance by pathogenic bacteria and the like due to edible safety. The ethylene control type preservative always occupies an important position in the preservation of fruits and vegetables, but most of the ethylene control type preservatives are effective for respiration transition type fruits and vegetables, and the defect of high use cost exists. Therefore, it is necessary to develop an efficient, safe, inexpensive and easily implemented green preservation method.

Sodium alginate is a natural polysaccharide, and has good biocompatibility, film forming property, adsorptivity, permeability and hygroscopicity. When the aqueous solution is coated on the surfaces of fruits and vegetables, a low-oxygen high-carbon-dioxide closed environment can be formed, the respiration of the fruits is inhibited, the glossiness of the fruits is improved, and the sensory quality of the fruits is improved. At present, a great deal of sodium alginate is applied to the research of fruit and vegetable fresh-keeping. The sodium alginate oligosaccharide is a degradation product of sodium alginate, is formed by connecting alpha-L-mannuronic acid and beta-D-guluronic acid through 1, 4-glycosidic bonds, has good water solubility, also has various biological activities on plants, and can promote the growth of the plants, induce the plants to generate antitoxin, enhance the cold resistance and drought resistance of the plants and relieve the damage of salt stress on the plants. The sodium alginate oligosaccharide has the characteristics of multiple functions and environmental protection, and also has the advantages of low cost, small application amount and the like, and has wide application prospect in agricultural production. However, as a small molecular weight oligosaccharide, the sodium alginate oligosaccharide has no reported effect on postharvest preservation without film forming property and is applied to postharvest vegetable and fruit preservation technology.

The patent provides a preservation method for processing fruits and vegetables by adopting picked sodium alginate oligosaccharides, and the method can relieve physiological metabolism of the picked fruits, inhibit metabolic pathways of cell walls of the fruits and vegetables by effectively regulating expression of genes related to fruit and vegetable ripening and softening, and delay the softening and ripening of the picked fruits and vegetables. Particularly, the method has obvious regulation and control effect on abscisic acid approach, is suitable for non-respiratory transition type fruits and vegetables, and overcomes the defect that the application range of the ethylene control type preservative is limited to respiratory transition type fruits and vegetables in the prior art. The method has the characteristics of obvious fresh-keeping effect, environmental protection, low cost, simple operation and the like, and is suitable for large-scale popularization.

Disclosure of Invention

The invention aims to provide a green preservation method for vegetables and fruits.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the invention relates to a method for preserving vegetables and fruits, which is to treat the vegetables and fruits with sodium alginate oligosaccharide aqueous solution after the vegetables and fruits are harvested.

In the method for preserving the vegetables and fruits, the mass concentration of the sodium alginate oligosaccharide in the applied sodium alginate oligosaccharide solution is 0.05-0.5G/L, the M/G value is 5/5-7/3, and the average molecular weight is 500-2000 Da. M represents mannuronic acid in the sodium alginate oligosaccharide, and G represents guluronic acid in the sodium alginate oligosaccharide.

The vegetable and fruit preservation method provided by the invention comprises the steps of soaking the vegetable and fruit for 1-5min after harvesting, and then naturally drying.

The method can remarkably prolong shelf life of picked vegetable and fruit under normal temperature and low temperature storage conditions. Meanwhile, the fruit and vegetable quality can be maintained.

The invention has the advantages and beneficial effects that:

(1) the vegetable and fruit preservation method provided by the invention can delay the self physiological metabolism of the picked vegetable and fruit, inhibit the metabolic pathway of the cell wall of the fruit and vegetable by effectively regulating the expression of the mature and softening related gene of the fruit and vegetable, and delay the softening and maturation of the picked vegetable and fruit. Particularly, the method has obvious inhibition effect on abscisic acid pathway and is suitable for non-respiratory transition type fruits and vegetables.

(2) The sodium alginate oligosaccharide used by the vegetable and fruit fresh-keeping method provided by the invention belongs to natural products, and has no pollution to the environment and no health hazard to human bodies after being used for vegetable and fruit fresh-keeping. The edible safety of the vegetables and fruits is guaranteed. Therefore, the method is a novel and green vegetable and fruit preservation method.

(3) The vegetable and fruit preservation method provided by the invention has the advantages of simple application process, low cost and easy popularization and application. Compared with the prior art, the application range of the ethylene control type preservative is limited to respiratory transition type fruits and vegetables in the prior art, the preservation period is long, the quality and the flavor of the fruits and vegetables are good, and the development and application prospects are good.

Drawings

FIG. 1 shows transcriptional regulation of alginate oligosaccharide on strawberry cell wall hydrolase gene, wherein A is strawberry pectin lyase FaPL, B is strawberry pectin methylesterase FaPE, and C is strawberry endoglucanase FaEG.

FIG. 2. Effect of sodium alginate oligosaccharide on strawberry abscisic acid and conjugate content thereof, wherein A is abscisic acid (ABA) and B is abscisic acid glycoconjugate (ABA-GE).

FIG. 3 shows transcriptional control of alginate oligosaccharide on strawberry abscisic acid signaling pathway gene, wherein A is FaNCED (ABA synthetic gene), B is FaASR (ABA signal transduction pathway gene), C is FaCHLH (ABA receptor gene), and D is FaPYR1(ABA receptor gene).

Detailed Description

The invention is further illustrated by the following examples: