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Lactose Concentration (lactose + concentration)

Distribution by Scientific Domains
Chemistry85%

Selected Abstracts

Optimization of process parameters by Taguchi method in the recovery of lactose from whey using sonocrystallization

CRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2010
S. R. Patel
Abstract Anti-solvent crystallization of lactose in the presence of ultrasound will reduce crystal size and the level of agglomeration as compared to the commercial cooling crystallization. It offers a potential route to enhance the physical properties as well as the rapid recovery of lactose. Since lactose recovery itself can reduce biological oxygen demand of whey by more then 80%, recovery of lactose from dairy waste stream (whey) solves the problems of dairy industries by improving economics of whey utilization and pollution reduction. In the present study, recovery of lactose from partially deproteinated whey using an anti-solvent (acetone) by sonocrystallization was optimized for finding the most influencing operating parameters; such as sonication time, anti-solvent concentration, initial lactose concentration in the whey and initial pH of sample mixture at three levels using L9 -orthogonal method. The responses were analyzed for recovery of lactose from whey. The anti-solvent concentration and the sonication time were found to be most influencing parameters for the recovery of lactose and the recovery of lactose was found to be 89.03% at the identified optimized level. The crystal size distribution of recovered lactose was found to be narrower (2.5 , 6.5 ,m) as compared to the commercial lactose crystals (3.5 , 9.5 ,m). (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Batch kinetics and modelling of ethanolic fermentation of whey

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2005
Salman Zafar
Summary The fermentation of whey by Kluyveromyces marxianus strain MTCC 1288 was studied using varying lactose concentrations at constant temperature and pH. The increase in substrate concentration up to a certain limit was accompanied by an increase in ethanol formation, for example, at a substrate concentration of 10 g L,1, the production of ethanol was 0.618 g L,1 whereas at 50 g L,1 it was 3.98 g L,1. However, an increase in lactose concentration to 100 g L,1 led to a drastic decrease in product formation and substrate utilization. The maximum ethanol yield was obtained with an initial lactose concentration of 50 g L,1. A method of batch kinetics was utilized to formulate a mathematical model using substrate and product inhibition constants. The model successfully simulated the batch kinetics observed at S0 = 10 and 50 g L,1 but failed in case of S0 = 100 g L,1 because of strong substrate inhibition. [source]

Batch production of L(+) lactic acid from whey by Lactobacillus casei (NRRL B-441)

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2004
Ali O Büyükkileci
Abstract The effects of temperature, pH, and medium composition on lactic acid production by Lactobacillus casei were investigated. The highest lactic acid productivity values were obtained at 37 °C and pH 5.5. The productivity was 1.87 g dm,3 h,1 at 37 °C in shake flasks. In the fermenter, a productivity of 3.97 g dm,3 h,1 was obtained at pH 5.5. The most appropriate yeast extract concentration was 5.0 g dm,3. Whey yielded a higher productivity value than the analytical lactose and glucose. Initial whey lactose concentration did not affect lactic acid productivity. MnSO4 ·H2O was necessary for lactic acid production by L casei from whey. Product yields were approximately 0.93 g lactic acid g lactose,1. Copyright © 2004 Society of Chemical Industry [source]

Production of ,-galactosidase from recombinant Saccharomyces cerevisiae grown on lactose

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2004
Lucília Domingues
Abstract Improved productivity and costs reduction in fermentation processes may be attained by using flocculating cell cultures. The production of extracellular heterologous ,-galactosidase by recombinant flocculating Saccharomyces cerevisiae cells, expressing the lacA gene (coding for ,-galactosidase) of Aspergillus niger under the ADHI promotor and terminator in a bioreactor was studied. The effects of lactose concentration and yeast extract concentration on ,-galactosidase production in a semi-synthetic medium were analysed. The extracellular ,-galactosidase activity increased linearly with increasing initial lactose concentrations (5,150 g dm,3). ,-Galactosidase production also increased with increased yeast extract concentration. During the entire fermentation, no accumulation of the hydrolysed sugars, glucose and galactose, was observed. The catabolic repression of the recombinant strain when cultured in a medium containing equal amounts of glucose and galactose was confirmed. In complete anaerobiosis, the fermentation of lactose resulted in a very slow fermentation pattern with lower levels of ,-galactosidase activity. The bioreactor operation together with optimisation of culture conditions (lactose and yeast extract concentration) led to a 21-fold increase in the extracellular ,-galactosidase activity produced when compared with preliminary Erlenmeyer fermentations. Copyright © 2004 Society of Chemical Industry [source]

Batch kinetics and modelling of ethanolic fermentation of whey

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2005
Salman Zafar
Summary The fermentation of whey by Kluyveromyces marxianus strain MTCC 1288 was studied using varying lactose concentrations at constant temperature and pH. The increase in substrate concentration up to a certain limit was accompanied by an increase in ethanol formation, for example, at a substrate concentration of 10 g L,1, the production of ethanol was 0.618 g L,1 whereas at 50 g L,1 it was 3.98 g L,1. However, an increase in lactose concentration to 100 g L,1 led to a drastic decrease in product formation and substrate utilization. The maximum ethanol yield was obtained with an initial lactose concentration of 50 g L,1. A method of batch kinetics was utilized to formulate a mathematical model using substrate and product inhibition constants. The model successfully simulated the batch kinetics observed at S0 = 10 and 50 g L,1 but failed in case of S0 = 100 g L,1 because of strong substrate inhibition. [source]

Production of ,-galactosidase from recombinant Saccharomyces cerevisiae grown on lactose

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2004
Lucília Domingues
Abstract Improved productivity and costs reduction in fermentation processes may be attained by using flocculating cell cultures. The production of extracellular heterologous ,-galactosidase by recombinant flocculating Saccharomyces cerevisiae cells, expressing the lacA gene (coding for ,-galactosidase) of Aspergillus niger under the ADHI promotor and terminator in a bioreactor was studied. The effects of lactose concentration and yeast extract concentration on ,-galactosidase production in a semi-synthetic medium were analysed. The extracellular ,-galactosidase activity increased linearly with increasing initial lactose concentrations (5,150 g dm,3). ,-Galactosidase production also increased with increased yeast extract concentration. During the entire fermentation, no accumulation of the hydrolysed sugars, glucose and galactose, was observed. The catabolic repression of the recombinant strain when cultured in a medium containing equal amounts of glucose and galactose was confirmed. In complete anaerobiosis, the fermentation of lactose resulted in a very slow fermentation pattern with lower levels of ,-galactosidase activity. The bioreactor operation together with optimisation of culture conditions (lactose and yeast extract concentration) led to a 21-fold increase in the extracellular ,-galactosidase activity produced when compared with preliminary Erlenmeyer fermentations. Copyright © 2004 Society of Chemical Industry [source]