It was observed that mushroom mycelium powder absorbed more water than did wheat flour. More water was added for the hydration of mycelium powder so that the added water in the formula would not influence the hydration of wheat flour and thereby, not affect the final volume of the bread. The observation is consistent with the finding of Lin et al. (2008) and Tseng et al. (2010), in which fruiting body powder was used. Therefore, an extra 5% amount of water was added for 5% mycelium-supplemented bread. Specific volumes (volume/weight) of mycelium-supplemented bread were 5.56–6.08 cm3/g, lower than that of white bread (Table 1). It seems that the addition of mycelia resulted in mycelium-supplemented bread with smaller size, as shown in Fig. 1. The specific volume of standard bread is in the range of 3.5–6 cm3/g (CGPRDI, 1983). However, all these mycelium supplemented breads met the passing level of specific volumes.