Compound antistaling agent for prolonging loquat fruit storage life and preparing method thereof

Abstract

The invention discloses a compound preservative and a preparation method for extending the storing time of loquat fruit, which comprises the following steps: 1) adding 9-15g nanometer calcium carbonate into 1L water with a temperature of 70-90 DEG C, mixing evenly and heat insulating, and then adding in 1.5-4.5g sodium stearate, water bath heat treating for 20-40min for modification; 2) heating and dissolving 300-450g chitosan in 29L water, and then mixing evenly with the solution in step 1). The compound preservative of the invention can effectively inhibit the browning and spoilage of loquat fruit, maintain the good fruit rate of loquat fruit, improve the editable quality and commercial value of loquat fruit and extend the storage period. The preparation method of the invention is characterized by simplicity, high efficiency and utility, which is suitable for large scale commercial application and has broad application prospect.

Description

technical field

[0001] The invention relates to fruit fresh-keeping technology, in particular to a composite preservative for prolonging the storage time of loquat fruit and a preparation method thereof. Background technique

[0002] Chitosan is a high molecular polymer extracted from the shell of crustaceans. Studies in recent years have shown that chitosan coating has a certain fresh-keeping effect on fruits and vegetables, but due to the mechanical strength of the film formed Low, and very sensitive to water, so its performance must be improved. Adding nano-materials to chitosan coating materials to enhance the fresh-keeping effect has become a current research hotspot. At present, nano-silver and nano-TiO 2 , nano-SiOx, etc. have been reported in fruit and vegetable preservation, but the research on the preservation of nano-calcium carbonate is still in its infancy. Calcium carbonate is a widely used inorganic filler, which has the advantages of wide sources, low cost...

Examples

Embodiment 1

[0015] ① Take 9g of nano-calcium carbonate, add 1L of 70°C water, stir evenly and keep it warm, then add 1.5g of sodium stearate, and keep it in a water bath for 20 minutes for modification. ②Take 300g of chitosan, heat and dissolve it in 29L of water, and then mix it with the above solution in ① evenly. Choose loquats that are basically the same size and color, without damage, diseases and insect pests, soak them in the above-mentioned compound preservation solution for 3 to 5 minutes, remove and dry them, then put them in cartons with a height of 30 to 40 cm, and place them in 20 to 25 Store at ℃ for 6 days.

Embodiment 2

[0017] ① Take 15g of nano-calcium carbonate, add 1L of 90°C water, stir evenly and keep it warm, then add 4.5g of sodium stearate, and keep it in a water bath for 40min to modify. ②Take 450g of chitosan, heat and dissolve it in 29L of water, and then mix it with the above solution in ① evenly. Choose loquats that are basically the same size and color, without damage, diseases and insect pests, soak them in the above-mentioned compound preservation solution for 3 to 5 minutes, remove and dry them, then put them in cartons with a height of 30 to 40 cm, and place them in 20 to 25 Store at ℃ for 6 days.

Embodiment 3

[0019] ① Take 12g of nano-calcium carbonate, add 1L of 80°C water, stir evenly and keep it warm, then add 3.5g of sodium stearate, and keep it in a water bath for 30 minutes to modify. ②Take 350g of chitosan, heat and dissolve it in 29L of water, and then mix it with the above solution in ① evenly. Choose loquats that are basically the same size and color, without damage, diseases and insect pests, soak them in the above-mentioned compound preservation solution for 3 to 5 minutes, remove and dry them, then put them in cartons with a height of 30 to 40 cm, and place them in 20 to 25 Store at ℃ for 6 days.

[0020] The good fruit rate of loquat fruit is shown in the table below (with clear water soaking as the control).

[0021] deal with

2 days

4 days

6 days

Group A

81.7％

67.2％

41.3％

Group B

91.4％

87.1％

70.6％

Group C

97.2％

90.1％

73.8％

Group D

95.9％

92.2％

...

technical field

[0001] The invention relates to fruit fresh-keeping technology, in particular to a composite preservative for prolonging the storage time of loquat fruit and a preparation method thereof. Background technique

[0002] Chitosan is a high molecular polymer extracted from the shell of crustaceans. Studies in recent years have shown that chitosan coating has a certain fresh-keeping effect on fruits and vegetables, but due to the mechanical strength of the film formed Low, and very sensitive to water, so its performance must be improved. Adding nano-materials to chitosan coating materials to enhance the fresh-keeping effect has become a current research hotspot. At present, nano-silver and nano-TiO 2 , nano-SiOx, etc. have been reported in fruit and vegetable preservation, but the research on the preservation of nano-calcium carbonate is still in its infancy. Calcium carbonate is a widely used inorganic filler, which has the advantages of wide sources, low cost...

Examples

Embodiment 1

[0015] ① Take 9g of nano-calcium carbonate, add 1L of 70°C water, stir evenly and keep it warm, then add 1.5g of sodium stearate, and keep it in a water bath for 20 minutes for modification. ②Take 300g of chitosan, heat and dissolve it in 29L of water, and then mix it with the above solution in ① evenly. Choose loquats that are basically the same size and color, without damage, diseases and insect pests, soak them in the above-mentioned compound preservation solution for 3 to 5 minutes, remove and dry them, then put them in cartons with a height of 30 to 40 cm, and place them in 20 to 25 Store at ℃ for 6 days.

Embodiment 2

[0017] ① Take 15g of nano-calcium carbonate, add 1L of 90°C water, stir evenly and keep it warm, then add 4.5g of sodium stearate, and keep it in a water bath for 40min to modify. ②Take 450g of chitosan, heat and dissolve it in 29L of water, and then mix it with the above solution in ① evenly. Choose loquats that are basically the same size and color, without damage, diseases and insect pests, soak them in the above-mentioned compound preservation solution for 3 to 5 minutes, remove and dry them, then put them in cartons with a height of 30 to 40 cm, and place them in 20 to 25 Store at ℃ for 6 days.

Embodiment 3

[0019] ① Take 12g of nano-calcium carbonate, add 1L of 80°C water, stir evenly and keep it warm, then add 3.5g of sodium stearate, and keep it in a water bath for 30 minutes to modify. ②Take 350g of chitosan, heat and dissolve it in 29L of water, and then mix it with the above solution in ① evenly. Choose loquats that are basically the same size and color, without damage, diseases and insect pests, soak them in the above-mentioned compound preservation solution for 3 to 5 minutes, remove and dry them, then put them in cartons with a height of 30 to 40 cm, and place them in 20 to 25 Store at ℃ for 6 days.

[0020] The good fruit rate of loquat fruit is shown in the table below (with clear water soaking as the control).

[0021] deal with

2 days

4 days

6 days

Group A

81.7％

67.2％

41.3％

Group B

91.4％

87.1％

70.6％

Group C

97.2％

90.1％

73.8％

Group D

95.9％

92.2％

...