Performance Evaluation of paddy straw pasteurizer for mushroom cultivation. Agricultural mechanization in Asia, Africa and Latin America

Abstract

Pa d d y s t r aw fou n d t o b e o n e of the most efficient substrate for mush room cultivation. Since the straw is mainly composed of lignin a nd cellu lose t hat a re deg r a ded enzymatically in the course of sub - strate utilization by the fungus. The edible mushrooms utilize ligno- cellulose as a source of carbon for thei r g row th th rough en z y matic degradation. But very often a num - ber of competitive fungi are found t o g r ow i n p a d d y s t r aw d u r i ng mushroom cultivation which af - fects the spawning rate, mycelium growth and mushroom yield. Hence p a s t e u r i z a t io n i s a n i m p o r t a n t process to prevent the growth of these competitor fungi and make the substrate more favourable for mushroom mycelia growth. For ef - fective paddy straw pasteurization, a pasteurizer was developed and its performance was evaluated. Straw was pasteurized after soaking in normal water and without soaking. Different temperature-time combi - nations and compression levels was used. Substrate obtained was used to cultivate three commonly culti - vated mushroom species in India. Hypsizygus ulmariusn , Pleurotus Sajor-caju and Calocybe Indica of - fered highest yields of 290.7 g/kg substrate with biological efficiency of 79.6 %, 254.1 g/kg substrate with biological efficiency of 69.6 % and 342.3 g/kg substrate with biological efficiency of 93.8 %, respectively. Contamination was absent when straw was pasteurized at 80 ºC for 2 h under maximum compression