National Announcement

On April 16, 2014, the National Health and Family Planning Commission (NHFPC) issued the Announcement on the Approval of 6 New Food Ingredients, including Chitosan (No.6 of 2014), officially approving Chitosan, Silymarin Seed Oil, Willow Leaf Wax Plum, Eucommia androgynus, Lactic Acid Schizococcus, and Pentosan Schizococcus as new food ingredients.

The main components, basic information, production process, serving size, quality requirements and other descriptions of chitosan are shown below:

Applications of Chitosan

Chitosan has received widespread attention in the past decades for its applications in biomedical, food, and chemical industries. However, chitosan is only soluble in acidic solution, which limits the play of its biological activity. Its degradation product, chitooligosaccharide, has been a hot research topic for researchers since its discovery, and it has even been listed as a key research project of sugar engineering in various countries.

Chitosan is the only positively charged, alkaline, water-soluble polysaccharide found in nature with superior biological activity, which can be prepared from chitin and chitosan, and is regarded as the sixth life element. It is found that chitosan has good antibacterial and antioxidant properties, which makes it an ideal preservative for fruits and vegetables;

Chitosan has the effect of improving immunity, inhibiting the growth of cancer cells, promoting the absorption of minerals, proliferating part of the human body’s beneficial bacterial flora, and preventing the three highs, and it is the best-selling health care functional food in Japan, the United States, South Korea, etc.; chitosan as an oligosaccharide can also be used as a food ingredient to add to the food for the improvement of the flavor and so on.

Freshness preservation of fruits and vegetables

Microbial growth and oxidative deterioration are the main factors affecting the shelf life of food, food preservation technology has made a certain breakthrough in the role of chemical preservatives, however, with the increase in consumer demand, consumers prefer food that does not contain chemical preservatives, therefore, natural preservatives have attracted attention.

The secondary structure of chitosan is net-like, which can effectively lock water molecules, and the polar groups in the molecule can form interactions with water molecules, affecting the water activity and resistance to flow, so chitosan has a good hygroscopicity and moisture retention, and antibacterial effect is remarkable, antioxidant prominence, and both inhibit respiration, improve the defense mechanism of fruits and vegetables, it is a natural food preservative preservative with excellent performance.

Deng Lili et al. found that after treating citrus fruits with 1.5% concentration of chitosan, the quality of citrus during the storage period could be effectively maintained and the morbidity rate was reduced. Yao Pingjia et al. synthesized a chitosan-based polymer, and the test results showed that 1% and 2% solutions of this polymer had good freshness preservation effect on mango, and the titratable acid content, soluble solids, V, weight loss rate, and good fruit rate of mango were better than those of the untreated mango after 17d of storage.

Chen Yizhao et al. found that 2% chitosan coated film can effectively inhibit the activity of PPO enzyme, slowing down the browning of peach, in order to alleviate the deficiencies of film-forming chitosan, to the appropriate proportion of PVP can be added to produce a good effect of preservation of film one.

Functional food

As chitosan has many unique physiological functions, safe and non-toxic, soluble under neutral conditions, it can be used as functional food. Generally speaking, prebiotics are oligosaccharides, so chitosan can also be prebiotics used in functional foods.

Studies have shown that DP2-8 fully deacetylated chitosan has a promoting effect on the growth of bifidobacteria and lactobacilli. Microencapsulation of chitosan into milk can be incorporated into commercial healthy dairy products and the incorporation does not affect the physical and sensory properties of the product; however, further exploration is needed to further improve the physical and sensory properties of cholesterol-lowering milk and to develop other similar cholesterol-lowering products.

Several studies have shown that chitooligosaccharides can inhibit tumor growth by inducing apoptosis and stimulating the activity of the immune system in animal tests, and suggested that chitooligosaccharides should be used in anti-tumor foods.

In animal tests, researchers have found that chitosan, DP3-7, can increase calcium absorption and reduce osteoporosis in mice by studying femur strength and calcium content in feces, and chitosan has also been found to inhibit the formation of insoluble calcium salts in a neutral environment in vitro.

Chitosan can form complexes with fatty acids and triglycerides, which can be eliminated from the body and reduce the amount of calories obtained by the body to achieve the purpose of slimming, so chitosan can be applied in functional beverages for weight loss and slimming, detoxification and immunomodulation.

Cho et al. found that chitosan can stimulate the activity of mitochondria to reduce fatigue, which is expected to be used in anti-fatigue food. Zhao Yuqing et al. evaluated the safety of chitosan functional food and proved that chitosan functional food is safe and non-toxic.

Food Ingredients

The United Kingdom and the United States have fully carried out scientific research on chitosan, and in Japan oligosaccharides are characterized as the only health food that can be advertised as efficacious and mandatorily used as a food additive after clinical practice.In 2014, the Office of China’s Health and Welfare Commission intends to approve chito-oligosaccharides as a new food ingredient.

Chitosan has obvious anti-bacterial efficacy and can be used as a natural preservative product to replace chemical preservatives such as sodium benzoate in food products such as condiments. When 0.24% or 0.48% oligosaccharides mixture was added to raw milk and stored at 4℃ for 12d, the number of thermophilic and cryophilic bacteria decreased by at least 3 orders of magnitude, the change of pH was very small, and the shelf-life of raw milk in 4℃ environment was extended by at least 4d.

It was found that the combination of chitooligosaccharides and lysozyme acted as a synergistic effect and was more effective against Gram-negative bacteria, and the use of this mixture in meat storage completely eliminated Escherichia coli, Pseudomonas fluorescens, and Bacillus cereus, and prolonged the shelf-life of minced meat by up to 15 d in a refrigerated environment.

The addition of chitooligosaccharides to tofu had no effect on the physicochemical properties of tofu such as moisture content, yield, color and turbidity, however, it gave the tofu lower hardness and smaller protein aggregates, and chitooligosaccharides did not affect the other sensory properties of the tofu except for a little bitterness.

The addition of chitooligosaccharides to traditional pickle curing provided better inhibition of coliforms and sensory superiority over sauerkraut obtained using traditional pickling methods. Chitosan can be used as a food additive to improve the structure and texture of food, and improve the water retention property of food. When fed to animals as feed, chitosan can promote animal growth, improve animal intestinal health, reduce animal diseases, and further improve the quality of meat-derived food.