Effect on density and dry matter losses of vacuum in vacuum-packed polythene bags silage

The objectives of this study were determined to effect of vacuum treatments and to measure densities and dry matter losses in vacuum-packed polythene bags silage. Maize (Zea mays L.) was harvested at two maturity stage (30% and 45% dry matter) and ensiled in packages. In the experiment was made 3 vacuum treatments (0.07mPa, 0.1mPa and -0.1mPa). And vacuum-packing machine a model CAS CVP 260 PD type was used. In all experiments, the chopped material was packed into polythene bags (dimensions 200x250 mm). Three different types polythene bags (PA/PE, BOPA/PE and OPP/PE/EVOH/PE) were examined. Vacuum-packed bag silages were opened after 15 days, 45 days,80 days and at the end of one year of ensiling. Results showed that, average dry matter loss in the vacuum-packed bag silages was 8.85, 10.96, and 6.08% after end of the one year, respectively. The highest dry matter loss was BOPA/PE type bags. Dry matter loss affected by at the stage of maturity and vacuum treatments (P<0.05). Density ranged from 0.11 to 0.34 g cm-3. At all bag silages density increased linearly with increasing moisture while decreased with increasing vacuum level (P<0.05).