The effects of temperature, humidity and reaction time on chemical composition, degradability and fermentability of palm date frond

This Research was conducted in 2007 at Animal Science Research Institute of Iran in order to study the effect of steam pressure on nutritive value of Palm date leaves under various contrrolled conditions of time (120، 180، 240، 300 and 360 secondes) and moisture (30، 40، 50 and 60 perecent) with pressure of 20 atmosphere using a completely randomized design factorial model with three replications. The chemical composition، in vitro gas production and in situ degradability of cell wall were significantly influenced by different levels of moisture and reaction time and also their interactions (P< 0. 05). The content of lignin increased considerably because of lignin like productions compared with other cell wall constituents. Steam treatment also increased water soluble carbohydrate content from 4. 85% (control) to 8. 05 (50% moisture - 240 seconds) but decreased with prolonged processing time. Total extractable phenolics increased considerabley from 3. 61% (control) to 5. 99 (40 moisture and 300 seconds). Increased harshness of treatment resulted in dry matter loss. The greatest amount of dry matter loss was related to sample inclusion 30% moisture and treated 360 seconds. NDF content also decreased. however it was increased in some of the treatments with harshness of treatment. The content of ADF increased significantly as compared with the control. Finally the samples treated under 40% - 180 (moisture-reaction time) was considered as the selected treatment because of the highest amount of gas production from in vitro gas test method.