Superfine grinding, as a new type of foodstuff processing, produces a narrow and uniform particle size distribution in Agrocybe chaxingu Huang. The suitable processing conditions of superfine grinding are: the feeding pressure of 0.5 MPa, the grinding pressure of 0.6 MPa, the feeding velocity of 0.0105 g/s, the feeding particle size of 150-500 mum and only one pass through the grinder. The experiments showed that the smaller was the superfine particle dimension, the greater were the fluidity, the water holding capacity and protein solubility. (C) 2004 Elsevier Ltd. All rights reserved.