Healthy Brown Rice-Based Extrudates Containing Straw Mushrooms: Effect Of Feed Moisture And Mushroom Powder Contents

This study was carried out to compare the nutritional values, total phenolic content (TPC), and antioxidant activity (AOA) of straw mushroom between egg-shaped (ME) and fully expanded pileus (MF) stages. Effects of three levels of feed moisture (FM: 13, 16, and 19%) and four levels of straw mushroom powder (MP: 0, 10, 15, and 20) were also investigated. It was set a constant barrel temperature profile due to temperature is not a factor for this study. The reseult showed that MF had higher nutritional values than ME. Increasing MP resulted in increased true density (TD), TPC, and AOA but decreased expansion ratio (ER), lightness, and texture hardness of extruded snacks. Increasing FM resulted in increased TD and texture hardness but decreased ER, lightness, TPC, and AOA of extruded snacks. The optimum formulation of extruded snacks predicted by RSM was 13-14% FM and 14-17% MP. This study demonstrated that it was possible to incorporate straw mushroom and brown rice mixtures into extruded snacks that were nutritious and acceptable to consumers. Practical applications Mushrooms have been incorporated in normal diets and increasingly popular as an ingredient in many food products. Straw mushrooms (Volvariella volvacea (Bull. ex Fr.) Sing.) are popular for consumption in Asian countries because of their availability all year round, ease of purchase, and their unique flavor and texture. This study demonstrated that it was possible to produce nutritious snacks containing straw mushroom (14-17%) and brown rice mixtures using extrusion process.