Characterization of stipe and cap powders of mushroom (Lentinus edodes) prepared by different grinding methods

The effects of micronization methods, mechanical and jet millings, on the physico-chemical properties of mushroom (Lentinus edodes) powder were investigated in contrast to shear pulverization. The powders of dried mushroom cap and stipe were prepared to obtain six powders. Compared to shear pulverization, mechanical and jet millings effectively reduced particle size and brought about a narrow and uniform particle size distribution. With the same material, powders from mechanical and jet millings had higher values in soluble dietary fiber content, surface area, bulk density, water soluble index and nutrient substance solubility, but lower values in the angles of repose and slide, water holding and swelling capacities than shear pulverized powder. These indexes were tightly dependent on particle size with absolute coefficients beyond 0.8330. With the same grinding method, cap powders possessed higher values in water soluble index, swelling capacity, bulk density, protein and soluble dietary fiber than stipe powders. (C) 2011 Elsevier Ltd. All rights reserved.