Biodegradable composite film used for fresh keeping package of edible mushrooms and preparation method thereof

Abstract

The invention relates to a biodegradable composite film used for fresh keeping package of edible mushrooms and a preparation method thereof. The preparation method includes steps of: 1) soaking a polylactic acid thin film, as a base film, in a polyethyleneimine solution for amination, water-washing and drying the film, acidifying the film in diluted hydrochloric acid, and water-washing and dryingthe film to produce a modified base film; 2) soaking the modified base film in a chitosan solution and water-washing and drying the modified base film to prepare a first composite film; 3) preparing afilm coating solution by dissolving sodium alginate, calcium chloride and cinnamic acid in water; 4) uniformly coating one side of the first composite film with the film coating solution and drying the film coating solution to form a coating layer. The biodegradable composite film is used for fresh keeping package of edible mushrooms and can delay the respiratory effect and after-ripening effectof the edible mushrooms, thus reducing browning and weight loss rate of the edible mushrooms and effectively keeping the edible mushrooms fresh. The composite film can prolong the storage life and normal temperature shelf life of the edible mushrooms and is suitable for being promoted.

Description

technical field [0001] The invention belongs to the technical field of fresh-keeping packaging of edible fungi, in particular to a biodegradable composite film for fresh-keeping packaging of edible fungi, and also relates to a preparation method of the biodegradable composite film for fresh-keeping packaging of edible fungi. Background technique [0002] Edible fungi, also known as mushrooms, have fleshy or gelatinous fruiting bodies, and are large edible fungi; common edible fungi include shiitake mushrooms, oyster mushrooms, Agaricus bisporus, Flammulina velutipes, Pleurotus eryngii, fungus, white fungus, etc. Edible fungi are rich in protein and amino acids, the content is several times to dozens of times that of ordinary vegetables and fruits, and its amino acid composition is relatively comprehensive. Most mushrooms contain eight kinds of amino acids necessary for the human body, and also contain various vitamins and various Mineral elements with physiological activity....

AI Technical Summary

Problems solved by technology

Although methods such as vacuum cooling, controlled atmosphere refrigeration, and irradiation fresh-keeping have certain effects, they are not suitable for promotion and use because of high equipment costs, huge initial investment, and cumbersome operations; After it is placed on the shelf and stored at room temperature, the above-mentioned corruption and deterioration problems will still occur in a short period of time

The chemical preservation method is cheap, but there is a problem of chemical reagent residue, which has adverse effects on the human body and the environment and hidden safety hazards, and is gradually abandoned by people.

Coating film preservation is a kind of natural sugar, protein, lipid, etc. as the main raw materials, which are coated on the surface of edible fungi by spraying, dipping, etc., and after drying, an imperceptible transparent edible film layer is formed. Bacteria play a fresh-keeping method with an antiseptic effect; coating preservation has a certain preservation effect on edible fungi with large and plump mushroom bodies, but for small and dense edible fungi such as Flammulina velutipes and tea tree mushrooms, coating preservation is inconvenient to operate and Large dosage, uneconomical, poor effect

[0005] Now the shelf life of edible mushrooms is commonly used for freshness preservation. The plastic wrap is generally made of refractory plastic film materials such as polyethylene, polyvinyl chloride or polyvinylidene chloride. Although it is light in weight and cheap, the plastic film is easy to produce Harmful gas, peculiar smell, and easy to cause white pollution. Its extensive use has caused great harm to people's living environment. The existing plastic plastic wrap packaging edible fungus is not a green and environmentally friendly packaging method.

Images