Fermentation efficiency

Lactic acid bacteria were immobilized in Ca-alginate beads prepared from different concentration of Na-alginate (1.0%, 2.0%, 4.0%, 6.0% and 8.0% w/v) and their fermentation efficiencies were investigated in liquid pineapple waste containing 31.3 gL of glucose... 

Thornton and coworkers (48) have used classical hybridization techniques, mating homothallic spores to heterothallic spores or cells, to improve winemaking properties, including fermentation efficiency, glycerol production and flocculation. 

S. cerevisiae does not provide a reliable tool for optimizing wine sensory properties. Strains may be selected for optimizing fermentation efficiency, or ethanol or sulfur dioxide tolerance, but the strain-specific production of volatiles appears to be highly variable. Much of the research has focused on the concentration of volatiles produced (which may show strain-specific... 

Ethanol inhibition is one of the principal factors restricting fermentation rate, yeast activity, and the maximum ethanol concentration achievable during ethanol fermentation. In order to maintain fermentation efficiency, relatively dilute substrate concentrations of 200 g/1 or less are often used resulting in a final ethanol concentration of around 100 g/1 after 48 to 72 h. Therefore, high ethanol tolerance is a desirable characteristic of yeast strains in order to improve the overall process economy [4]. Another approach to minimize ethanol inhibition is to remove ethanol from the fermentation broth during fermentation. 

The kinetics of substrate removal in the anaerobic reactor actually determines the SRT required for a given fermentation efficiency. In turn, the presence of the UF unit allows a fine control of SRT, making process control easier, When high biomass concentrations are achieved, longer SRTs can be maintained at lower reactor volumes. 

Cells for Increasing Fermenter Efficiencies. The tower fermenter system used is described in Figure 3. Wort was used as the ethanol source, and an inociilum of an aggregating strain of Acetobacter species was prepared and added to the tower fermenter (2 litres capacity). When the level of acetic acid in the fermenter had reached about 3% w/v, the medium delivery pump was started and the flow rate adjusted to a level that gave almost complete conversion of the ethanol available into acetic acid. Undue haste in increasing the flow rate and also serious decrease or stoppage of the air flow caused the expected fall in conversion efficiency. Adjustment of the flow and aeration rate showed that a maximum V. E. of 0.82 could be attained (see Table I). 

Pichia stipitis (Scheffersomyces stipitis) Xylose fermentation Efficient xylose utilization [6]... 

Thermotolerant yeast can be isolated from rotten strawberries. The yeast cells are immobilized on calcium alginate and can be reused eight times at 40°C with a 100% fermentation efficiency (2). 

Kodama, Y., Fukui, N., Ashikari, T., Shibano, Y, Morioka-Fujimoto, K., Hiraki, Y, et al. (1995). Improvement of maltose fermentation efficiency constitutive expression of MAE genes in brewing yeasts. Journal of the American Society of Brewing Chemists, 53, 24-29. 

Increases fermentation efficiency by reducing diacetyl formation. 

Daniel et al. 2009 Papalexandratou and De Vuyst 2011 Papalexandratou et al. 201 Ic, 2013 Pereira et al. 2012 Crafack et al. 2013). As the variation of yeast species is much larger than that of bacterial species, the presence of the former may have profound effects on the fermentation efficiency and fermented cocoa bean quality, either directly or indirectly (Meersman et al. 2013). 

Table 8.2 Fermentation efficiency of SCO production from lignocellulosic resources... 

Tchakouteu, S., Kalantzi, O., Gardeh, C., Koutinas, A.A., Aggelis, G., Papanikolaou, S., 2015. lipid production by yeasts growing on biodiesel-derived cmde glycerol strain selection and impact of substrate concentration on the fermentation efficiency. Journal of Applied Microbiology 118 (4), 911-927. 

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