Northeast Forestry University

Lijuan Wang

Jian Li

Ruoting Liu

Yuping Ning

Zijing Pan

Wenrui Chi

Na Wei

A preparation method of a high-barrier antibacterial flame-retardant food packaging film solves problems that an existing food packaging film is non-degradable, poor in preservation effect, and inflammable. The preparation method includes: performing blending reaction on chitosan quaternary ammonium salt and phytic acid to generate a polyelectrolyte complex; and adding the polyelectrolyte complex into a polyvinyl alcohol solution, heating the polyvinyl alcohol solution added with the polyelectrolyte complex to obtain a film-forming solution, pouring the film-forming solution into a mold, leveling and drying the film-forming solution to obtain the high-barrier antibacterial flame-retardant food packaging film. The food packaging film has water vapor permeability in 1.82-2.58×10g·s·m·Pa, oxygen permeability in 1.63-12.31 cm·mm·Pa·day, and a value of limiting oxygen index (LOI) in 28.10%-33.33%. The food packaging film performs an instant self-extinguishing behavior after ignition; and can inhibitandwhen used in packaging.

Preparation method of high-barrier antibacterial flame-retardant food packaging film

A press-sealing method of anionic polysaccharide films is disclosed, aiming to solve the technical problem that the existing polysaccharide films are difficult to be press-sealed into a bag. The press-sealing method includes following steps. (1) A chitosan quaternary ammonium salt solution is prepared. (2) An anionic polysaccharide film is pretreated. (3) The chitosan quaternary ammonium salt solution is applied to a part to be sealed between two anionic polysaccharide films, and the part be sealed is pressed for 1˜2 s under conditions of a pressure of 0.3˜0.5 MPa and a temperature of 20˜30° C. to complete the press-sealing. The press-sealing strength of the anionic polysaccharide films after press-sealing is 1.38±0.26˜6.95±0.95 N/15 mm. It is used for packaging beef tallow and other foods, can effectively prolong the shelf life of foods, and can be used in the field of food packaging.

Press-sealing method of anionic polysaccharide films

A preparation method and an application method of a multifunctional intelligent cellulose-based visual label are provided. The multifunctional intelligent cellulose-based visual label solved a problem that an existing freshness indicator film is narrowed in an indication range. The preparation method includes the following steps: step 1 of carboxylation modification; step 2 of cationic grafting; step 3 of preparation of a composite dye solution; step 4 of preparation of responsive fibers; and step 5 of performing vacuum filtration to prepare paper, thereby obtaining the multifunctional intelligent cellulose-based visual label. The food freshness is indicated with the obtained intelligent visual label. An indicated pH value range is 4-8, color variation can be completed within 30 seconds, and the food freshness can be accurately indicated. The multifunctional intelligent cellulose-based visual label is low-carbon, efficient, green, safe, and wide in the indication range, and can be used in food monitoring.

Growing community of inventors

Harbin, China

Lijuan Wang