A review of the use of Hydrocolloids in Texture-Modified Foods for the Management of Dysphagia
Dysphagia refers to difficulty swallowing which is estimated to affect more than 800 million people worldwide and occurs by conditions (e.g. neurological diseases, aging, stroke, head and neck cancers). Swallowing is one of the most complex and coordinated physiological activities that human beings engage in but patients with dysphagia may have impaired safe intake of food and liquids, necessitating innovative solutions to avoid complications including aspiration pneumonia, malnutrition, dehydration. Dietary modification, most notably in terms of texture-modified foods (TMFs) and thickened liquids, has emerged as one of the mainstay non-pharmacological approaches in dysphagia management. Due to their unique capacity of modifying viscosity and bolus cohesion at swallowing, stability; hydrocolloids are a major formulation component in these type of foods. These biopolymers consisting of polysaccharides and proteins are common food ingredients to be used as thickening, gelling and stabilizing agents in various food systems; hence utilised in dysphagia diets. This review aims to give an comprehensive overview of the unique characteristics that hydrocolloids play to modify food consistency for patients with dysphagia. The paper first considers the pathophysiology of dysphagia and its nutrition implications, then provides a background on the International Dysphagia Diet Standardisation Initiative (IDDSI) framework for food textures and liquid thickness classification. It explores functional and physicochemical properties of hydrocolloids, focusing on their rheological behaviour and the production of swallowing-safe products. This has led to efforts aimed at leaving the corresponding backgrounds of dysphagia and its diet in reformation, selecting appropriate hydrocolloids for use as thickening vehicles in persons with dysphagia and analysing their properties such as molecule thickening and stability as well as teaching how thickness can help take care of swallowing situation between mechanisms. The review also emphasizes the role of rheological characterization in safe swallowing and optimal bolus flow. In addition, the uses of hydrocolloids in thickened beverages, pureed meals and ready-to-eat dysphagia products are also described. This article critically reviews the challenges of hydrophilic hydrocolloids investigated for food fortification purposes, in particular with regards to sensory acceptance, variability in viscosity and risk of nutritional dilution. The article is also reviewed to assess the potential of novel approaches (eg, hydrocolloid blends, microstructural design and 3D food printing) in developing high-quality or personalized diets for dysphagia management. In conclusion, hydrocolloids serve as functional components to enhance the safety, stability and palatability of texture-modified foods frequently consumed by dysphagia patients. Ongoing endeavours to elucidate the mechanism of hydrocolloid action, as well as investigations into optimally rheological properties and consumer acceptability, will ultimately work to inform improvements in dysphagia management