Food thickening agents: Sources, chemistry, properties and applications - A review

Food thickening agents are widely used to modify rheological and textural properties as well as to enhance the quality attributes. Improvement in moisture binding capacity, structural modification and altering flow behavior properties are the major functions of food thickeners. Modified starches, proteins, individually or in combination with exudates and seed gums, seaweed extracts and, most recently, microbial polysaccharides, are found to have the ability to improve product mouthfeel, handling properties, and stability characteristics. Factors such as temperature, shear, pH, ionic strength, etc., have effects on the functionality of these thickening agents and must be carefully optimized by food processors while formulation. Moreover, the type of thickener utilized has an impact on the product functionality. The addition of a protein-based thickener boosts the amino acid content (arginine, cysteine histidine, lysine, proline and γ-aminobutyric acid) and favors the nutritional and rheological properties. However, realigning the polymer chains reduces the interaction between the adjacent molecules and results to decrease viscosity. Steric stabilization or network formation by the bacterial cellulose fibrils were the possible factors for production of stable emulsions. Future research into various sources of food thickeners may aid in achieving the required culinary features.