Sugars concentrations

Alcoholic Fermentation. Certain types of starchy biomass such as com and high sugar crops are readily converted to ethanol under anaerobic fermentation conditions ia the presence of specific yeasts Saccharomyces cerevisia and other organisms (Fig. 6). However, alcohoHc fermentation of other types of biomass, such as wood and municipal wastes that contain high concentrations of cellulose, can be performed ia high yield only after the ceUulosics are converted to sugar concentrates by acid- or enzyme-catalyzed hydrolysis ... 

Tamarind seed polysaccharide, the gum fraction obtained from tamarind kernel polysaccharide, forms gels over a wide pH range in the presence of high sugar concentrations (>65 wt%), and it can therefore substitute for fmit pectins (65). 

The sweet taste of sucrose is its most notable and important physical property and is regarded as the standard against which other sweeteners (qv) are rated. Sweetness is induenced by temperature, pH, sugar concentration, physical properties of the food system, and other factors (18—20). The sweetening powers of sucrose and other sweeteners are compared in Table 3. The sweetness threshold for dissolved sucrose is 0.2-0.5% and its sweetness intensity is highest at 32-38°C (19). 

Density. Measurement of density is widely used in the sugar industry to determine the sugar concentration of symps, Hquors, juices, and molasses. The instmment used is called a hydrometer or a spindle. When it is graduated in sucrose concentration (percent sucrose by weight), it is called a Brix hydrometer or a Brix spindle. Brix is defined as the percent of dry substance by hydrometry, using an instmment or table caUbrated in terms of percent sucrose by weight in water solution. Hydrometers are also graduated in °BaumH, stiU in use in some industries. The relationship between °BaumH and density, ing/cm, is °Baumn Baum e = 145(1 — 1/d). 

This is the reverse Pasteur or Crabtree effect and is also known as glucose inhibition or cataboHte repression. In the presence of higher sugar concentrations, synthesis of respiratory enzymes such as cytochromes is inhibited. 

The effect of osmotic pressure on yeast activity is of great importance, and is often overlooked. At salt concentrations up to 1.5%, the effect is slight salt concentrations of 2—2.5%, which are common in bread doughs, inhibit yeast activity considerably. Likewise, sugar concentrations above 4% produce apparent inhibition. Consequently, yeast-raised sweet doughs (15—20% sugar), contain very high yeast concentrations. 

Fermentation of fmit juices other than grapes, principally apple juice, is the same as that in the production of grape wine. For the production of mm, cane molasses is diluted to a sugar concentration of 15—29% the sucrose, glucose, and fmctose is completely fermented within 36 h at 30—32°C. 

Balling. Balling is a measure of the sugar concentration in a grain mash, expressed in degrees. It approximates percent by weight of the sugar in solution. 

Studies show that the production of 1kg dry biomass requires 2.0 kg sugar, 0.7 kg oxygen, 0.1 kg ammonia, with the liberation of 12,300 k Joules heat. A typical continuous fermentation operates at a dilution rate (D) = 0.2 h 1, with sugar concentration of 3% (w/v) in the incoming medium. With a fermentor of 50 m3 capacity and 90% utilisation of carbohydrate [ie 0.3% (w/v) sugar in the outgoing medium] what would be ... 

Time, hours DO, mg/1 Optical density, absorbance, 520,11m Cell dry weight, mg/ml Protein concentration, g/1 Sugar concentration, g/1 Yield, Ym... 

A 20 m3 working volume of a bioreactor is used for producting penicillin. What would be the sugar concentration (S0) you choose if oxygen transfer rate is not the limiting reactant Given data ... 

Table 8.1 presents the results of the ICR retention time studies, sugar concentration (dual substrate) studies and cell density. The kinetic model for ICR was derived on the basis of a first order reaction, plug flow and steady-state behaviour. 

Reactor productivity was obtained by dividing final ethanol concentration with respect to sugar concentration at a fixed retention time. It was found that the rates of 1.3, 2.3 and 2.8 g 1 1 h 1 for 25, 35 and 50 g 1 1 glucose concentrations were optimal. Ethanol productivities with various substrate concentrations were linearly dependent on retention time (Figure 8.12). The proportionality factor may have increased while the substrate... 

Time, h DO, mgT-1 Citric acid concentration, gT-1 Cell dry weight, gT-1 Sugar concentration, gT-1... 

A bioreactor of V = 20 m3 working volume produces penicillin. What sugar concentration will you choose if OTR is not limited ... 

The energy substrates are contraindicated in patients with hypersensitivity to any component of the solution. Dextrose solutions are contraindicated in patients with diabetic coma with excessively high blood sugar. Concentrated dextrose solutions are contraindicated in patients with increased intracranial pressure, delirium tremens (if patient is dehydrated), hepatic coma, or glucose-galactose malabsorption syndrome Alcohol dextrose solutions are contraindicated in patients with epilepsy, urinary tract infections, alcoholism, and diabetic coma... 

Table Z14 Variation in selected acyl sugar concentrations as a function of latitude in Lycopersicon pennelli (from Shapiro et al., 1994)...

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