堆積、裝填密度與貯存時間對玉米青貯料發酵品質及開封後穩定性的影響

The effects of piling up, packing density and storage on fermentation quality and aerobic stability of corn silage

王紓愍(Shu-Min Wang) ； 陳嘉昇(Chia-Sheng Chen)

《畜產研究》 47卷3期 (2014/09) Pp. 187-194

摘要

本試驗以實驗室規模青貯進行，目的在了解堆積、裝填密度與貯存時間對青割玉米青貯品質及開封後穩定性的影響。試驗共進行高密度（D, 500kg/m^3）、低密度（1/2D, 250kg/m^3）、堆積24小時高密度（P+D）和堆積24小時低密度（P+1/2D）四種處理，以及48天與168天二個開封時間。結果顯示，所有處理開封時的青貯品質都為優良等級，但pH值與發酵產酸在處理間有顯著差異。堆積處理與低密度處理之pH值都較高，此外，低密度處理組的丁酸含量也較高，評分較低。延長貯存時間，乳酸含量降低，pH值、乙酸及丁酸含量增加。以貯存168天的青貯料進行開封後穩定性調查顯示，隨青貯料接觸空氣的時間拉長，所有處理都出現溫度及pH值上升的現象，溫度的反應先於pH值，其中以P+1/2D處理的損壞發生時間明顯較其他處理提前。綜合上述，顯示堆積及低裝填密度等處理，增加材料與氧氣接觸時間，容易發生pH及丁酸含量較高的情形，即使開封時品質可接受，但隨貯存時間增長，品質劣化程度增加且開封後穩定性較差。

關鍵字

玉米青貯 ； 發酵品質 ； 開封後穩定性

並列摘要

The purpose of this research is to investigate the effects of piling up, packing density and time of storage on fermentation quality and aerobic stability of corn silage by laboratory scale ensiling. Four ensiling treatments combing different packing density and piling up were conducted in this experiment and silos were opened and sampled for analysis on day 48 and day 168, separately. All treatments were in ＂good＂ score at the time of silo opening, but significant difference existed in voltaic acid profile and pH value. Higher pH value was found in treatments of piling up and treatment of low packing density. Treatments of low packing density also had higher butyric acid content and lower silage score. Contents of lactic acid decreased and pH value, acetic acid, and butyric acid increased according to prolonging of storage time. Aerobic stability was investigated with silos opened on day 168. Temperature and pH value increased in all treatments according to time exposed to air, and increase of temperature was previous to increase of pH value. The combing treatment of piling and low density spoiled faster than the other treatments. The results indicated that piling up and low packing density prolonged the time of aerobic activity when ensiling and it was apt to raise pH value and butyric acid content. Thought the silage quality might be acceptable at first, their quality would be getting worse accord to storage time and also bad for aerobic stability.

並列關鍵字

Corn silage ； Fermentation quality ； Aerobic stability