Gellan gum is a kind of microbial metabolic adhesive with excellent properties and functions. It is becoming a kind of food additive after carrageenan, Agar and Xanthan gum. It is mainly used as thickener, coagulant, suspending agent and film-forming agent in candy, jelly, jam, bread stuffing, ice cream and other food manufacture. At present, people lack a complete understanding of the biosynthesis mechanism of gellan gum, and there are some problems in fermentation, such as low biological concentration, low conversion rate and high extraction cost, which seriously restricts the application of gellan gum. There are high acyl gellan gum and low acyl gellan gum in the market, and the acyl group content of the gellan gum is different, which leads to the different Rheological and gel properties of the gellan gum.
Gellan gum is a kind of biological polysaccharide obtained by microbial fermentation after xanthan gum by (Kelco) Company in the United States in 1980s. In 1982, researcher Kang (Kang) et, reported for the first time that the laboratory successfully produced gellan gum through Pseudomonas aeruginosa. The commercial scale production of gellan gum is the result of successful screening of microorganisms. In 1988, Japan successfully completed the toxicological experiment of gellan gum and allowed the gellan gum to be used in food. In 1992, the Food and Drug Administration of the United States approved the use of gellan gum as stabilizer and binder in food. Since then, gellan gum has become the third microbial extracellular polysaccharide used in food. In 1996, China also approved it as a food thickener, stabilizer (GB2760-2014), which can be used appropriately in all kinds of foods according to the needs of normal production. After dissolution of high acyl gellan gum, it is thicker and more cohesion, so it is suitable for thickener. The high acyl gellan gum is softer than the low acyl gellan gum, and the water retention and elasticity are very good. The deformation ability of high and low acyl gellan gum can be 4 times as high as that of low acyl gellan gum. These characteristics make the high acyl gellan gum have more application.
Widely used in many fields of food in food industry.
The gellan gum formed by high acyl gel has high transparency, brittleness and moderation, and can show good flavor release characteristics. High acyl gellan gum can usually be used in combination with other food glue, so that food can obtain good sensory, texture and stability requirements. Gellan gum and other food glue have good compatibility. Gel food glue such as carrageenan, Agar and so on, although similar to the gel properties of gellan gum, but the gellan gum has advantages in flavor release, acid stability, thermal reversibility, usage and so on. The gellan gum has the effect of anti-aging and inhibiting the aging and viscosity of corn starch paste during storage. Gellan gum is not easy to lead to enzyme hydrolysis, which provides good flexibility for food processing. At present, the application of high acyl gellan gum in food includes: the unique elasticity and cementitious property of high acyl gellan gum make it can be used in jelly, jam and sweet food; high acyl gellan gum can be used in drinks, dairy products, ice cream, stuffing, etc., and high acyl gellan gum can be used in frosting and icing. High acyl gellan gum has strong water holding capacity and can be used in cake and cheese to moisturize, keep fresh and keep shape.
The rapid growth of demand for gellan gum.
Gellan gumis the first polysaccharide colloid gelling agent produced by biological fermentation in the world. It has the advantages of low dosage, high transparency, strong aroma release ability, acid resistance, enzyme resistance and so on. According to the relevant research groups, before 2005, the domestic market was almost completely monopolized by American companies, and since 2005, the proportion of gellan gum in the Chinese market has become larger and larger. Although the domestic market demand is growing rapidly, but the domestic gellan gum production scale is small, the energy consumption cost is high. Foreign companies can produce more specifications of gellan gum, domestic manufacturers can produce less specifications of gellan gum, but high acyl gellan gum can not be produced basically, and there are many problems in the production process, such as high energy consumption, complicated product extraction, difficult product clarification, difficult product purification and so on. In recent years, the production technology of high acyl gellan gum has become mature in domestic, some technical problems have been solved, and the performance-price ratio of the products has been higher than that of foreign products. However, at present, the basic research and application research of gellan gum in China are insufficient, and many of the application technology of gellan gum is only in the hands of a small number of professional compound manufacturers. The research on gellan gum, especially high acyl gellan gum, is mainly carried out in combination with western food and other products. For example, many foreign consumers like to eat brittle jelly, but Chinese consumers do not like to eat brittle jelly, like elastic jelly. How to combine domestic gellan gum, especially high acyl gellan gum with Chinese characteristic food or traditional food, is an important subject in front of scientific and technological personnel in colloid industry in our country.