Food packaging occupies an important position in food production and circulation, but while bringing benefits and convenience to people, there are also environmental pollution problems caused by packaging waste. Therefore, in recent years, the preparation and application of edible packaging films have been carried out at home and abroad. According to the research, the edible packaging film has the characteristics of green environmental protection, safety and biodegradability. It can ensure the quality of food through the performance of oxygen resistance, moisture resistance and solute migration, so as to extend the shelf life of food. The edible inner packaging film is mainly made of biological macromolecular materials, which has a certain mechanical strength and low oil, oxygen and water permeability, so as to prevent the leakage of seasoning juice or oil, and the seasoning will be damp and mildewed In addition, it has a certain water solubility and is convenient to eat. With the rapid development of my country’s convenience food processing industry, the application of edible inner packaging films in condiments will gradually increase in the future.
01. Sodium carboxymethyl cellulose

Sodium carboxymethyl cellulose (CMC-Na) is a carboxymethylated derivative of cellulose and is the most important ionic cellulose gum. Sodium carboxymethyl cellulose is usually an anionic polymer compound prepared by reacting natural cellulose with caustic alkali and monochloroacetic acid, with a molecular weight ranging from several thousand to millions. CMC-Na is white fibrous or granular powder, odorless, tasteless, hygroscopic, easy to disperse in water to form a transparent colloidal solution.

Sodium carboxymethyl cellulose is a kind of thickener. Due to its good functional properties, it has been widely used in the food industry, and it has also promoted the rapid and healthy development of the food industry to a certain extent. For example, due to its certain thickening and emulsifying effect, it can be used to stabilize yogurt drinks and increase the viscosity of yogurt system; because of its certain hydrophilicity and rehydration properties, it can be used to improve the consumption of pasta such as bread and steamed bread. quality, prolong the shelf life of pasta products, and improve the taste; because it has a certain gel effect, it is conducive to the better formation of gel in food, so it can be used to make jelly and jam; it can also be used as an edible coating film The material is compounded with other thickeners and applied on the surface of some foods, which can keep the food fresh to the greatest extent, and because it is an edible material, it will not cause adverse effects on human health. Therefore, food-grade CMC-Na, as an ideal food additive, is widely used in food production in the food industry.

02. Sodium carboxymethylcellulose edible film

Carboxymethyl cellulose is a cellulose ether that can form excellent films in the form of thermal gels, so it is widely used in the pharmaceutical and food industries. Carboxymethyl cellulose film is an efficient oxygen, carbon dioxide and lipid barrier, but it has poor resistance to water vapor transmission. Edible films can be improved by adding hydrophobic materials, such as lipids, to the film-forming solution Therefore, it is also known as a potential lipid derivative.

1. CMC-lotus root starch-tea tree oil edible film can meet the requirements of greenness, safety and pollution-free, which not only ensures the quality of food but also does not reduce the packaging effect. It is expected to be developed and applied in instant noodles, instant coffee, instant oatmeal and soybean milk powder in the future. The inner packaging bag replaces the traditional plastic film.

2. Using carboxymethyl cellulose as film-forming base material, glycerin as plasticizer, and adding cassava starch as auxiliary material to prepare condiment edible composite film, it is more suitable for packaging of vinegar and powder packs stored within 30 days and Long-term grease wrapping film.

3. Using lemon peel powder, glycerin, and sodium carboxymethylcellulose as film-forming raw materials for lemon peel edible films

4. Using sodium carboxymethyl cellulose aqueous solution as the carrier and food-grade nobiletin as the raw material, a composite coating material of nobiletin-sodium carboxymethyl cellulose was prepared to extend the shelf life of cucumbers