The separation of lactic acid from lactose in the ultrafiltration permeate of cheese whey broth was studied using a cross-flow nanofiltration membrane unit. Experiments to test lactic acid recovery were conducted at 3...
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The separation of lactic acid from lactose in the ultrafiltration permeate of cheese whey broth was studied using a cross-flow nanofiltration membrane unit. Experiments to test lactic acid recovery were conducted at 3 levels of transmembrane pressure (1.4, 2.1 and 2.8 MPa), two levels of initial lactic acid concentration (1.7% and 2.7%), and two types of nanofiltration membranes (DS5DK and DS-5HL). Higher transmembrane pressure caused significantly higher permeate flux and higher lactose and lactic acid retention ratio (P
Cheese whey is one by-product that can be used to produce lactic acid. The processes of lactic acid production include two key stages which are (a) fermentation and (b) product recovery. In this project, lactic acid w...
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Cheese whey is one by-product that can be used to produce lactic acid. The processes of lactic acid production include two key stages which are (a) fermentation and (b) product recovery. In this project, lactic acid was produced from cheese whey using B. longum. After 48 hours of fermentation, nearly 100% of the lactose was converted and the lactic acid yield reached 0.81 g/g lactose utilized without any nutrient addition. Ultrafiltration membrane was used to separate cells and protein from the above fermentation broth. About 94% of the proteins were retained by the ultrafiltration membrane with MWCO of 5,000 and 20,000 Daltons. Nanofiltration membrane was used to further separate lactic acid from lactose in the ultrafiltration permeate, 99-100% of lactose can be retained in the concentrate and 40-60% of lactic acid can be recovered in the permeate using a nanofiltration membrane of DS-5DK. Higher initial lactic acid caused significant higher permeate flux, lower lactose retention, and higher lactic acid recovery. Increased transmembrane pressure caused significant higher permeate flux, higher lactose retention, and lower lactic acid recovery.
The FIRST (Feedstock Impregnation and Rapid Steam Treatment) approach was used in this study to isolate extractives, hemicellulose, lignin, fibers, and cellulosic fines of softwood. With hydrolysis and fermentation of...
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The performance of immobilized Bifidobacterium longum in sodium alginate beads and on a spiral-sheet bioreactor for the production of lactic acid from cheese whey was evaluated. Lactose utilization and lactic acid yie...
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作者：
Gayle, GodfreyRaczkowski, CharlesMims, Michele R.Bioenvironmental Engineering Program
Department of Natural Resources and Environmental Design North Carolina AandT State University 1601 East Market St NC 27411 United States Soil
Plant and Environmental Science Department of Natural Resources and Environmental Design North Carolina AandT State University 1601 East Market St NC 27411 United States
The impact of Tourism on fragile lands is an important concern to the Jamaican government. This study was conducted to evaluate an area in the Blue Mountain Region located in the eastern part of Jamaica, which is a pa...
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The impact of Tourism on fragile lands is an important concern to the Jamaican government. This study was conducted to evaluate an area in the Blue Mountain Region located in the eastern part of Jamaica, which is a part of a Forest reserve that has high potential for eco-tourism activity. The study sites were at an average elevation of 1,200 meters: the target soils were formed as a result of volcanic activities and contain large amounts of fem'hydrite and aluminum humus complexes. The objectives of this research were to: 1) Determine selected soil physical properties, 2) Evaluate the ability of the soil to withstand degradation from pedestrian traffic based on the physical properties determined, 3) Evaluate the soil types of the region by comparing the physical properties determined, in objective one, to specific physical and engineering properties of Andic soils as given by Dixon and Weed (1989). Measurements were made over a two and a half year period at three sites in the Blue Mountain Region. Results were statically analyzed and showed the effects of pedestrian traffic on trails were limited to the upper 20 cm of the soil for all properties evaluated. Impact on bearing capacity ranged from 0.66 MPa to 1.58 MPa when compared to non-traffic soil bearing capacity of 0.35MPa. Pedestrian traffic also increased bulk density by 30% (0.91 g/cm3 versus 1.30 g/cm3). Porosity was reduced by 15% to 34%. This reduction was due to soil compaction. The soil physical properties observed in the study compared favorably with Andic soil physical properties reported by Dixon and Weed (1989).
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