## 3 Functions of Dextran and Its Derivatives
### Applications of Dextrans in Products of Food Industry  
The main rationale for the application of dextran in food products is the property of dextran, being a fine white powder that dissolves readily in water at any temperature to prepare clear and viscous solutions. Moreover, dextran solutions are colorless, odorless, tasteless, and chemically inert, and therefore, these can be compatible with a variety of ingredients used in food items. Dextran has been suggested as a preservative coating for common perishable food products such as shrimp, meat, fruits, and cheese. Dextran can be produced by lactic acid bacteria, which are considered food-quality organisms that have been given the status of generally recognized as safe (GRAS) [5; 6; 7].  
Few LABs synthesize extracellular polysaccharide, which is a material of commercial interest for its physical-chemical properties. Considering this fact, the EPS-forming Lactic acid bacteria have been used in food fermentations. The presence of dextran released by bacteria contributes to improving the rheological characteristics of dairy products, for instance, viscosity, texture, and mouthfeel [54]. EPS are categorized as heteropolysaccharides, which are composed of several types of sugar units, including glucose, galactose, fructose, and rhamnose, whereas homopolysaccharides type contain only one type of monosaccharide unit, glucose or fructose [55]. Homopolysaccharides studied in species of _Lactobacillus_, _Leuconstoc_, and _Streptococcus_ are typically types of glucan or fruct, which are synthesized by extracellular enzyme glycan-sucrase consuming sucrose as the source of glycosyl (fructose or glucose) [56].  
[PERSON] et al. prepared dextran nanoparticles in the process of enzyme synthesis to study their application in delivery for nutraceuticals [57]. Food colloids binary and ternary complexes composed of up to three substances were studied for creating nanoparticles, which could be suitable for the fortification of bioactive composites in food products [28].  
Conjugates of whey protein and dextran were used as stabilizers for the physicochemical strength and for the bio-accessibility of \(\beta\)-carotene nano emulsions [29].  
The application of dextran in several food products is due to the characteristics of its flexibility in solubilization. The rheological properties in a product can be modified by using dextran of diverse molecular weights and types of branching in the polymer chain; hence, a dextran preparation matching the requirement can be selected accordingly [11]. Most applications of dextran as a polysaccharide have been investigated for food industry products. This polymer has been used in baking and confectionery for its exceptional moisturizing, stabilizing, and preserving properties [58]. Dextrans have also been explored for the improvement in flavor, texture, and consistency of several consumer-friendly products like ice creams, jellies, sauces, sweets, flour, breads, etc. [59].  
Dextran polysaccharides act as stabilizers of culinary characteristics like texture, aroma, and flavor in finished food products. Other than that, it has been added to products prepared with the main ingredients of cheese, meat, and vegetables in order to slow down the oxidation of products [60; 61]. Furthermore, dextran has been recommended as a suitable material for preparing biodegradable, edible coatings and films [62]. Dextran has been incorporated with another polymer, chitosan, in the fabrication of biodegradable material suitable as film for the packaging of mushrooms [63]. Dextran molecules of low molecular weights have been suggested as potential prebiotics for the sustainability of human gut microbiota [64; 65].