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Microbial gums possess the ability to form “gels” or increase the viscosity of a liquid. These properties are due to the specific macromolecular structural organization seen in these gums. Structural properties such as monomer composition, linkages among the residues, branched or unbranched structure, and neutral or charged properties are essential factors that are analyzed during characterization of these gums [2]. Techniques such as gas chromatography (GC) or high‐performance anion‐exchange chromatography (HPAEC) are used for monomer determination. Fourier‐transformed infrared spectroscopy is used for the analysis of functional groups present in microbial gums. Linkages present are determined by nuclear magnetic resonance like ¹H and ¹³C spectroscopy or by methylation analysis using GC [17].

Physicochemical properties of microbial gums are another critical factor, that when determined, can establish possible functional applications of microbial gums in various industries. Important physicochemical properties commonly analyzed include molecular weight determination, microstructure analysis, and determination of thermal properties. High‐performance size‐exclusion chromatography, accompanied by refractive index (RI) detector or for higher accuracy with multi‐angle laser light‐scattering detector, is generally used for molecular determination [18]. Microstructure analysis can be determined by different techniques such as scanning electron microscope and atomic force microscope, while the thermal analysis is carried out using thermal gravimetric analyzer and differential scanning calorimetry.

Different combinations of structural and physicochemical properties of these biopolymers can result in desirable properties for industrial applications. EPS produced from Streptococcus thermophilus CRL1190 has a high molecular weight (1782 kDa), and a porous microstructure, displaying high water holding capacity and oil holding capacity. EPS CRL1190 also possessed antioxidative, emulsifying, and flocculating activities [19].

Microbial gums have been utilized for the synthesis of hydrogels. Hydrogels can be described as hydrophilic polymeric networks that can imbibe large quantities of liquid. Hydrogels can be used to replace tissue as implants or scaffolds, and those made using microbial gums are nontoxic and biodegradable [1].