不同阻氧能力青贮袋对玉米青贮发酵品质和有氧稳定性的影响

Effect of different oxygen barrier silage bag on fermentation quality and aerobic stability of maize silage

为研究青贮袋阻氧能力对玉米青贮发酵品质及有氧稳定性的影响,试验将青贮饲料分别装在氧气透过量为2962.41、70.25、64.36、6.03cm^3/(m^2·24h·0.1MPa)4种青贮袋内(PE-50、SSOB-50、PAOB-50、EVOHOB-50),在30d和60d后进行取样检测,对其发酵品质、主要微生物和有氧稳定性进行分析。结果表明:发酵时间与青贮袋阻氧能力的交互作用对pH、水溶性碳水化合物(WSC)、干物质损失、乳酸、乙酸、NH3-N含量及酵母菌数量均有极显著影响(P<0.01)。增加青贮袋的阻氧能力可有效提高青贮玉米品质,延长有氧稳定时间。在发酵60d时,EVOH青贮袋内酵母菌数量最少,降至1.81lgcfu/gFW,pH最低,为3.74,有氧稳定时间显著高于尼龙和聚乙烯青贮袋,达到297h。综上,选用EVOH青贮袋贮存的青贮玉米效果最好。

The aim of this work was to assess the effects of different oxygen barrier silage bags on fermentation,microbial quality and aerobic stability.The oxygen transmission rate of four silage bag was 2962.41,70.25,64.36,6.03 cm3/(m2·24 h·0.1 MPa) respectively(PE-50、SS OB-50、PA OB-50、EVOH OB-50),the bags were filled with same quality fresh forge.After 30 d and 60 d,samples were collected for testing and analyzing the fermentation quality,microbial quantity and aerobic stability.The results showed that the effects of interaction of the silage bag's oxygen barrier ability and fermentation time on pH,water soluble carbobydrate(WSC),dry matter(DM) loss,lactic acid,acetic acid,NH3-N content and yeast quantity of maize silage were significant(P<0.01),enhancing impermeability to oxygen of the silage bag contributes to a reduction in the yeast count and to an increase in the aerobic stability of maize silage.After 60 days of fermentation,the maize silage stored in the EVOH silage bag had the lowest yeast count,down to 1.81 lg cfu/g FW,while the pH was the lowest(3.74).The aerobic stability was higher for silage conserved in the EVOH oxygen barrier bag,reaching to 297 h.Therefor,the EVOH silage bag was optimum for maize silage of this experiment.