Use of d-galacturonic acid in fruit preservation

Abstract

The application discloses application of D-galacturonic acid in fruit preservation. The fruit is treated by D-galacturonic acid to realize fruit preservation. The concentration of the D-galacturonic acid is 50 mmol / L. The fruit is an apple fruit. After the apple fruit is treated by the D-galacturonic acid, the hardness of the fruit is significantly improved, the content of original pectin is significantly increased, and the content of soluble pectin is significantly reduced. The method is good in preservation effect and safe and reliable.

Description

Technical Field

[0001] This invention relates to the field of fruit preservation technology, specifically to the use of D-galacturonic acid in fruit preservation. Background Technology

[0002] Plant cell walls are major contributors to plant structure, morphology, and properties. Pectin, an important component of cell walls, is widely distributed throughout the plant kingdom. It is abundant in waste biomass resources such as apple pomace and citrus peels. Structurally, pectin is a complex polysaccharide composed of an α-(1,4)-linked D-galacturonic acid backbone, with this monosaccharide accounting for over 70% of the polymer. D-galacturonic acid forms the backbone of three polysaccharide domains believed to be present in all pectin species: homogalacturonic acid (HGA), type I polyrhamnogalacturonic acid (RG-I), and type II polyrhamnogalacturonic acid (RG-II). These three polysaccharide domains can be covalently linked together, forming a pectin network throughout the primary cell wall matrix and intermediate lamellae. Even so, the practical applications of D-galacturonic acid are rarely reported.

[0003] Currently, fruit preservation methods are mainly divided into two types: physical preservation and chemical preservation. Physical preservation primarily slows down the respiration and metabolism of fruit through low-temperature storage, thereby delaying spoilage. Chemical preservation mainly inhibits the growth of spoilage bacteria or inhibits fruit oxidation by spraying chemical preservatives. Some of these methods are too costly, while others pose food safety issues. Therefore, a new fruit preservation method is needed, distinct from existing physical and chemical preservation methods, that is both effective and safe. Summary of the Invention

[0004] In view of the above-mentioned prior art, the purpose of this invention is to provide the application of D-galacturonic acid in fruit preservation. By using D-galacturonic acid, the treated apples show significantly increased firmness, significantly increased protopectin content, and significantly decreased soluble pectin content after a period of time; the preservation effect is good and safe.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A first aspect of the present invention provides the use of D-galacturonic acid in fruit preservation, wherein fruit is preserved by treating it with D-galacturonic acid.

[0007] Preferably, the concentration of D-galacturonic acid is 10–200 mmol / L.

[0008] Preferably, the concentration of D-galacturonic acid is 50 mmol / L.

[0009] Preferably, the fruit is an apple.

[0010] Preferably, the treatment is by injection, spraying, or soaking; the amount of injection or spraying is 200 μL / fruit; and the soaking time is ≥10 min.

[0011] A second aspect of the present invention provides a method for preserving apple fruit, comprising the following steps: injecting or spraying D-galacturonic acid into harvested apple fruit, or soaking harvested apple fruit in D-galacturonic acid.

[0012] Preferably, the injection or spraying dosage is 200 μL per fruit; and the soaking time is ≥10 min.

[0013] The beneficial effects of this invention are:

[0014] This invention significantly improves the firmness of apples treated with D-galacturonic acid, significantly increases the protopectin content, and significantly reduces the soluble pectin content; thus greatly extending the shelf life of apples, with good preservation effect and reliable safety. Attached Figure Description

[0015] Figure 1 This is a phenotypic diagram of the preservation of Fuji apples treated with the preservative prepared in the example;

[0016] Figure 2 The preservative prepared in the example treats the firmness of Fuji apples;

[0017] Figure 3 The original pectin content of the Fuji apple fruit prepared with the preservative in the example is shown.

[0018] Figure 4 The preservative prepared in the example contains the water-soluble pectin content of the treated Fuji apples.

[0019] Figure 5 The image shows the phenotypic pattern of the preservative prepared in the example, sprayed onto Red Fuji apples for preservation.

[0020] Figure 6 The firmness of the Fuji apple fruit sprayed with the preservative prepared in the example is shown. Detailed Implementation

[0021] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, 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 application pertains.

[0022] As described in the background section, existing fruit preservation methods are either too costly or pose food safety issues. Therefore, the purpose of this invention is to provide the use of D-galacturonic acid in fruit preservation. Although D-galacturonic acid is a building block of pectinic acid and a major component of pectin, there are currently no reports indicating that adding D-galacturonic acid to apples can increase protopectin content and decrease soluble pectin content. However, the inventors have found through research that using D-galacturonic acid can significantly increase protopectin content, decrease soluble pectin content, improve apple firmness, and greatly extend the shelf life of apples.

[0023] To enable those skilled in the art to better understand the technical solution of this application, the technical solution of this application will be described in detail below with reference to specific embodiments.

[0024] The test materials used in the embodiments of this invention are all conventional test materials in the art and can be purchased through commercial channels.

[0025] Example

[0026] D-galacturonic acid solutions of 10, 50, 100, and 200 mmol / L were prepared using distilled water and D-galacturonic acid (CAS No.: 91510-62-2) to obtain apple fruit preservatives of different concentrations, with distilled water as the control (the concentration of D-galacturonic acid solution was 0 mmol / L).

[0027] Test case

[0028] Apples from the same batch, of the same variety and specification, with no significant differences in freshness and other indicators, were selected. Different concentrations of the apple fruit preservative prepared in the example were injected into Fuji apples (10 apples per group, each weighing 356.89g ± 20.14g), with an injection volume of 200μL. After injection, the apples were placed in a dark incubator at 19℃ for approximately 10 days. Apples injected with distilled water served as a blank control. The firmness, protopectin content, and soluble pectin content of the apples in each group after 10 days of storage were measured. The results are shown in [Figure 1]. Figures 1-4 .

[0029] Figure 1 Phenotypic diagram of D-galacturonic acid treatment for the preservation of Fuji apples. The injection concentrations of D-galacturonic acid were 0, 10, 50, 100, and 200 mmol / L, and the treatment time was 10 days. Figure 2 It refers to the firmness of Red Fuji apples treated with D-galacturonic acid. Figure 3 It refers to the protopectin content of Red Fuji apples treated with D-galacturonic acid. Figure 4It refers to the soluble pectin content of Red Fuji apples treated with D-galacturonic acid.

[0030] Considering that injecting apples with preservatives is time-consuming and laborious in practical applications, apples from the same batch, of the same variety and specifications, with no significant differences in freshness and other indicators, were selected. Different concentrations of apple preservatives prepared in the examples were sprayed onto Fuji apples (6 apples per group, 334.31g ± 18.22g per apple). The entire apple was sprayed with the preservative, and after absorption, the spraying was repeated 4-5 times, with a total spray volume of 200μL. The apples were then placed in a dark incubator at 19℃ for approximately 10 days, with apples sprayed with distilled water serving as a blank control. The firmness of the apples in each group after 10 days of spraying was tested. The results are shown below. Figures 5-6 .

[0031] Figure 5 Phenotypic diagram of D-galacturonic acid spraying for the preservation of Fuji apples. The spraying concentrations of D-galacturonic acid were 0, 10, 50, 100, and 200 mmol / L, and the treatment time was 10 days. Figure 6 It refers to the firmness of Red Fuji apples sprayed with D-galacturonic acid.

[0032] The two experiments above show that the apples treated with the preservative prepared in the examples, at a concentration of 50 mmol / L, showed the best treatment effect.

[0033] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. Use of D-galacturonic acid for preserving fruits, characterized in that, The fruit preservation is achieved by treating the fruit with D-galacturonic acid; the fruit preservation includes: increasing the fruit hardness and protopectin content, and reducing the soluble pectin content; the concentration of the D-galacturonic acid is 50 mmol / L; and the fruit is an apple fruit.

2. Use according to claim 1, characterized in that, The treatment is injection, spraying or soaking; the injection or spraying amount is 200 μL per fruit; and the soaking time is ≥10 min.

3. A method for the preservation of apple fruit, characterized in that, The method comprises the following steps: Injecting, spraying or soaking the harvested apple fruit with D-galacturonic acid.

4. The method of claim 3, wherein, The injection or spraying amount is 200 μL per fruit; and the soaking time is ≥10 min.

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