Templin Tricia L, Johnston David B, Singh Vijay, Tumbleson M E, Belyea Ronald L, Rausch Kent D
Agricultural and Biological Engineering Department, University of Illinois, Urbana, 61801, USA.
Bioresour Technol. 2006 Sep;97(13):1536-45. doi: 10.1016/j.biortech.2005.06.006. Epub 2005 Aug 2.
Corn processing streams are characterized by high water content. Removal of water and recovery of solids are major economic and logistical challenges. New technologies are needed to modify processing streams and to reduce variability and improve quality of coproducts. The objective was to determine the effectiveness of microfiltration and ultrafiltration systems in altering water, solids (protein) and ash contents of corn processing streams. Corn was either steeped with SO(2) (STW) or soaked (SKW) in water; STW contained more solids than SKW. Ultrafiltration of STW and SKW had little effect on water removal or solids recovery. Corn was processed by a conventional wet milling process and a wet milling process that used enzymes to eliminate use of SO(2) steeping. Protein streams from the conventional process (CG) and the enzymatic process (EG) were processed by microfiltration. Permeate streams from EG and CG had higher total solids and ash concentrations than retentate streams; much of the ash was recovered in permeate (67% and 83%, respectively). For CG, proteins were largely recovered in retentate, whereas for EG, proteins were recovered in permeate. SDS-PAGE data indicated a decrease in size of proteins in the EG process stream. Permeate streams from microfiltration were subject to ultrafiltration; there was little effect on solids and nutrient separations.
玉米加工流的特点是含水量高。去除水分和回收固体是主要的经济和物流挑战。需要新技术来改变加工流，减少变异性并提高副产品质量。目的是确定微滤和超滤系统在改变玉米加工流中的水、固体（蛋白质）和灰分含量方面的有效性。玉米要么用SO₂浸泡（STW），要么在水中浸泡（SKW）；STW比SKW含有更多的固体。对STW和SKW进行超滤对除水或固体回收影响不大。玉米通过传统湿磨工艺和使用酶以消除SO₂浸泡的湿磨工艺进行加工。来自传统工艺（CG）和酶促工艺（EG）的蛋白质流通过微滤进行处理。EG和CG的渗透物流比截留物流具有更高的总固体和灰分浓度；大部分灰分在渗透物中回收（分别为67%和83%）。对于CG，蛋白质主要在截留物中回收，而对于EG，蛋白质在渗透物中回收。SDS-PAGE数据表明EG工艺流中蛋白质的大小有所减小。微滤的渗透物流进行超滤；对固体和营养物分离几乎没有影响。
