A Critical Review on the Development, Physicochemical Variations and Technical Concerns of Gluten Free Extrudates in Food Systems

The prevalence of celiac disease (CD) and other gluten-intolerant disorders is still growing over time partially attributed to more clinical investigations and improved diagnosis capacity, even mainly reported in many developed countries. Consequently, the demand for gluten-free (GF) food products is receiving increasing interest because of its use as profitable therapy for gluten-related disorders and the improved physiochemical and structural attributes. Recently, extrusion cooking, an emerging processing technique, largely has become the leading direction for the food industries in order to develop a large number of products such as pasta, noodles, snacks, etc. having different shapes, better nutritional, sensory, and functional characteristics. This vast range of GF-based extruded products is produced by different raw materials, such as pseudocereals, corn, rice, sorghum, and legumes at different extrusion parameters. Extrusion technology enables the control of various processes, such as mixing, cooking, shearing, and shaping of products. However, there are several concerns, such as starch-protein interaction, chemical structure capability, and textural, nutritional, and sensorial characteristics, that must be addressed for a successful and effective processing for GF foods. This review aims to provide complete details about the use of extrusion processing for the development of GF extrudates and the effect of parameters on the physicochemical, textural, and structural properties of extrudates. Additionally, it highlights the approaches to enhance the functional attributes of GF extrudates. There is a need to design unique food formulations as well as the extrusion process to meet the requirement of gluten-intolerant patients. Further work is warranted in developing and evaluating more GF-based extruded products, specifically the development of healthy and nutritious food products, and still, there is a great need to find a unique way to enrich the bio-functional components into the gluten-free extruded products.