การเพิ่มประสิทธิภาพกระบวนการผลิตอัลกอฮอลล์จากน้ำสับปะรด โดยวิธีการนำเซลยีสต์กลับมาใช้ในเครื่องหมักชนิดคอลัมน์ต่อเนื่อง / ศิริรัตน์ วงษ์วันทนีย์ = Improvement of alcohol production from pineapple juice by recycling yeast cells in continuous column fermenter / Sirirat Wongwantanee
In this study, the fermentation system consisted of one aerobic column and 8 anaerobic columns connected in series. Pineapple juice was used as raw material and fed into the studied fermenter continuously. The purpose of the study was to improve the efficiency of alcohol production by recycling yeast cells. The experimental results revealed that recycling of yeast cells could increase the ethanol production efficiency significantly. Recycling of the 5th column overflow provided the best results in term of dilution rate and alcohol yield. The yeast activity in converting sugar into ethanol from the first ethanol column was the highest value of the yeast activity in converting sugar into ethanol was form the first column and the activity decreased along the column number. An increase of the aeration rate resulted in increasing the yeast activities substantially. For the recycle of the 5th column overflow and the recycle ratio of 0.5 , the system had the highest dilution rate of 0.0330 h⁻¹ and the optimum aeration rate of 0.12 volume of air/volume of wort/time. The system could produced 11% ethanol and had the productivity of 3.72 g/l.h and the ethanol yield of 0.91 g ethanol/g sugar utilized.
