Impact of Extrusion Process on the Macro- and Micro-nutrient in Extruded Food Products: Challenges and Future Trends

Abstract

Micro-nutrient-rich extruded food products have become popular food products that are ready to eat. Extrusion technology (ET) is one of the widely used processes in developing such food products. ET operates multiple tasks in a single machine. Depending on the type of final product, ET can be a cold or hot process. This review discusses the fundamentals of the ET process including important parameters and types of extrusion process. A comprehensive discussion has been provided on the impact of ET on macro- and micro-nutrients of extruded food products. Besides, research and development of extruded food products are presented. Moreover, challenges and considerations as well as future trends in micronutrient-rich product development by extrusion process are highlighted. The literature suggested that screw geometry, compression ratio (CR), length over diameter (L/D) ratio, and flight clearance of extruder screw are important parameters of the extrusion system. Hence, these parameters and the composition of feed material influence the presence of nutrients in the final extruded product. The research indicated that various food processing by-products can be utilized for value-added applications in extruded products. However, several challenges and limitations of the ET such as acrylamide formation and nutrient stability needs to be considered. The emerging ET includes super critical fluid assisted extrusion, 3D printing–based extrusion that could enhance nutrient sustainability and precision extrusion. These innovative techniques could revolutionize the current extruded food product market by improved nutrient retention, personalized extruded food product, etc.