Cheese Whey Powder Solution Research Articles

Deproteinization: an integrated-solution approach to increase efficiency in β-galactosidase production using cheese whey powder (CWP) solution

Whey is the liquid that results from the coagulation of milk during cheese manufacture. Cheese whey is also an important environmental pollution source. The present experiment sought to compare β-galactosidase (EC 3.2.1.23) production by Aspergillus oryzae from deproteinized and un-deproteinized CWP solutions. β-galactosidase was produced by submerged fermentation in deproteinized or un-deproteinized CWP solutions. To determine the activity of the enzyme, a reaction mixture containing cell-free extract and ortho-Nitrophenyl-β-galactoside (ONPG) was used. The results indicated that β-galactosidase induction was greater when using deproteinized CWP solution compared to the un-deproteinized CWP solution. These results may enable an alternative management of cheese whey, thereby decreasing its impact on the environment and producing value-added biomacromolecules.

Continuous thermophilic hydrogen production from cheese whey powder solution in an anaerobic fluidized bed reactor: Effect of hydraulic retention time and initial substrate concentration

The focus of this study is the use of an anaerobic fluidized bed reactor (AFBR) to continuously produce hydrogen under thermophilic conditions (55 °C) using a range of cheese whey (CW) concentrations and hydraulic retention times (HRTs). The following combinations of tests parameters were evaluated: a fixed concentration of 4900 ± 200 mg lactose L−1 and HRTs of 8, 6, 4, 2, 1 and 0.5 h in AFBR1 and a fixed HRT of 6 h and influent CW concentrations of 2800 ± 100, 4900 ± 200, 6800 ± 300, 9800 ± 300 and 14,600 ± 300 mg lactose L−1 in AFBR2. For AFBR1, the maximum hydrogen production rate (HPR) obtained was 4.1 ± 0.2 L H2 h−1 L−1 in the HRT of 0.5 h, and maximum hydrogen yield (HY) of 3.67 ± 0.59 mol H2 mol lactose−1 in the HRT of 4 h. For AFBR2, the maximum HPR was 0.85 ± 0.12 L H2 h−1 L−1 at a concentration of 6800 ± 300 mg lactose L−1, and the maximum HY was 2.64 mol H2 mol lactose−1 at a concentration of 2800 ± 100 mg lactose L−1. In both reactors, the main metabolic products were acetic acid and butyric acid. Based on 16S rRNA clone analysis of the bacterial community, the identified sequences were affiliated with relative abundances of 48.42% (Thermoanaerobacterium and Thermohydrogenium kirishiense) and 75.53% (Thermoanaerobacterium thermosaccharolyticuum and T. kirishiense) in AFBR1 and AFBR2, respectively.

Effect of initial bacteria concentration on hydrogen gas production from cheese whey powder solution by thermophilic dark fermentation

Dark fermentative hydrogen gas production from cheese whey powder solution was realized at 55°C. Experiments were performed at different initial biomass concentrations varying between 0.48 and 2.86 g L(-1) with a constant initial substrate concentration of 26 ± 2 g total sugar (TS) per liter. The highest cumulative hydrogen evolution (633 mL, 30°C), hydrogen yield (1.56 mol H(2) mol(-1) glucose), and H(2) formation rate (3.45 mL h(-1) ) were obtained with 1.92 g L(-1) biomass concentration. The specific H(2) production rate decreased with increasing biomasss concentration from the highest value (47.7 mL g(-1) h(-1) ) at 0.48 g L(-1) biomass concentration. Total volatile fatty acid concentration varied beetween 10 and 14 g L(-1) with the highest level of 14.2 g L(-1) at biomass concentration of 0.48 g L(-1) and initial TS content of 28.4 g L(-1) . The experimental data were correlated with the Gompertz equation and the constants were determined. The most suitable initial biomass to substrate ratio yielding the highest H(2) yield and formation rate was 0.082 g biomass per gram of TS.

Mixotrophic cultivation of Chlorella vulgaris using industrial dairy waste as organic carbon source

Growth parameters and biochemical composition of the green microalga Chlorella vulgaris cultivated under different mixotrophic conditions were determined and compared to those obtained from a photoautotrophic control culture. Mixotrophic microalgae showed higher specific growth rate, final biomass concentration and productivities of lipids, starch and proteins than microalgae cultivated under photoautotrophic conditions. Moreover, supplementation of the inorganic culture medium with hydrolyzed cheese whey powder solution led to a significant improvement in microalgal biomass production and carbohydrate utilization when compared with the culture enriched with a mixture of pure glucose and galactose, due to the presence of growth promoting nutrients in cheese whey. Mixotrophic cultivation of C. vulgaris using the main dairy industry by-product could be considered a feasible alternative to reduce the costs of microalgal biomass production, since it does not require the addition of expensive carbohydrates to the culture medium.

The Macro Nutrient Removal Efficiencies of a Vertical Flow Constructed Wetland Fed with Demineralized Cheese Whey Powder Solution

This study aims to remove the macro-sized nutrients that are present in the cheese whey powder solution through the use of constructed wetland systems. For this purpose, 70% and 40% demineralized solutions of cheese whey powder were used. For both concentrations, control reactors are run in parallel with Typha angustifolia planted reactors for the duration of a 92 day period. Zeolite and gravel were used as the filling material. The planted reactor, which was fed with the 70% solution, was named as Cheese Whey Powder Solution (CWPS) 1 and its unplanted control was named CWPS 2 while the reactor, which was fed with the 40% solution, was named as CWPS 3 and its unplanted control was named CWPS 4. The removal of COD, PO4-P and NH4-N were obtained as 37.47%, 45.62%, and 68.88% in CWPS 1; 24.89%, 35.74%, and 63.15% in CWPS 2; 51.15%, 54.96%, and 64.13% in CWPS 3; and 28.35%, 23.99%, and 65.92% in CWPS 4, respectively.

Kluyveromyces Marxianus Biofilm in Cheese Whey Fermentation for Bioethanol Production

The feasibility of anaerobic fermentation of cheese whey using Kluyveromyces marxianus DSMZ 5422 biofilm on particle support was studied. Firstly the effect of the concentration of cheese whey powder solution and of the amount of inoculum used was tested. Results indicate that both these parameters have limited effect on substrate conversion and the concentration of the produced ethanol. Experiments of cheese whey fermentation in presence of natural supports, namely olive pits and walnut shells, was carried out to observe the holding capacity of K. marxianus on these supports. Results confirm the cell adhesion on the surface of olive pits and walnut shells and the suitability of this system for the development of biofilm technology fermentation.

Optimal fermentation conditions for maximizing the ethanol production by Kluyveromyces fragilis from cheese whey powder

Cheese whey powder (CWP) is an attractive raw material for ethanol production since it is a dried and concentrated form of CW and contains lactose in addition to nitrogen, phosphate and other essential nutrients. In the present work, deproteinized CWP was utilized as fermentation medium for ethanol production by Kluyveromyces fragilis. The individual and combined effects of initial lactose concentration (50–150 kg m−3), temperature (25–35 °C) and inoculum concentration (1–3 kg m−3) were investigated through a 23 full-factorial central composite design, and the optimal conditions for maximizing the ethanol production were determined. According to the statistical analysis, in the studied range of values, only the initial lactose concentration had a significant effect on ethanol production, resulting in higher product formation as the initial substrate concentration was increased. Assays with initial lactose concentration varying from 150 to 250 kg m−3 were thus performed and revealed that the use of 200 kg m−3 initial lactose concentration, inoculum concentration of 1 kg m−3 and temperature of 35 °C were the best conditions for maximizing the ethanol production from CWP solution. Under these conditions, 80.95 kg m−3 of ethanol was obtained after 44 h of fermentation.

Improved Ethanol Production by Mixed Immobilized Cells of Kluyveromyces marxianus and Saccharomyces cerevisiae from Cheese Whey Powder Solution Fermentation

Ethanol productions from cheese whey powder (CWP) solution were investigated by using free or immobilized cells of Kluyveromyces marxianus in monocultures or mixed cultures with free or immobilized cells of K. marxianus and Saccharomyces cerevisiae. K. marxianus free cells produced 3.8% v/v ethanol in monocultures, while S. cerevisiae immobilized cells produced 5.3% v/v ethanol in mixed cultures. The percentage of theoretical yield was found to be higher in mixed cultures than that in monocultures. The maximum ethanol fermentation efficiency was achieved (79.9% of the theoretical value) using mixed cultures of immobilized cells of K. marxianus and S. cerevisiae. The beads were relatively stable without significant reduction in activity for about eight batches of fermentation.

Fermentation of cheese whey powder solution to ethanol in a packed‐column bioreactor: effects of feed sugar concentration

AbstractBACKGROUND: Cheese whey powder (CWP) is a concentrated source of lactose and other essential nutrients for ethanol fermentation. CWP solution containing different concentrations of total sugar was fermented to ethanol in an up‐flow packed‐column bioreactor (PCBR) at a constant hydraulic residence time (HRT) of 50 h. Total sugar concentration in the feed was varied between 50 and 200 g L−1 and a pure culture of Kluyveromyces marxianus was used for ethanol fermentation of lactose. Variations of ethanol and sugar concentrations with the height of the column and with the feed sugar concentration were determined.RESULTS: Ethanol concentration increased and total sugar decreased with the column height for all feed sugar contents. The highest effluent ethanol concentration (22.5 g L−1) and ethanol formation rate were obtained with feed sugar content of 100 g L−1. Percentage sugar utilization decreased with increasing feed sugar content above 100 g L−1 yielding lower ethanol contents in the effluent. The highest ethanol yield coefficient (0.52 gE g−1S) was obtained with a feed sugar content of 50 g L−1. Biomass concentration also decreased with column height, yielding low ethanol formation in the upper section of the column.CONCLUSION: The packed column bioreactor was found to be effective for ethanol fermentation from CWP solution. The optimum feed sugar content maximizing the effluent ethanol and the specific rate of ethanol formation was found to be 100 g L−1. High sugar content above 100 g L−1 resulted in low ethanol productivities due to high maintenance requirements. Copyright © 2008 Society of Chemical Industry

Ethanol production from cheese whey powder solution in a packed column bioreactor at different hydraulic residence times

Cheese whey powder (CWP) solution containing 50 g L −1 total sugar was fermented to ethanol in a continuously operated packed column bioreactor (PCBR) using olive pits as support particles for cell attachment. Pure culture of Kluyveromyces marxianus (DSMZ 7239) was used in the PCBR for ethanol formation from lactose content of CWP solution. Sugar utilization and ethanol formation were investigated as function of the hydraulic residence time (HRT) between 17.6 and 64.4 h. Sugar concentration decreased with increasing ethanol concentration along the height of the column. Percent sugar utilization increased while effluent sugar concentration was decreasing with HRT between 17.6 and 50 h. Similarly, effluent ethanol concentration increased while ethanol productivity was decreasing with increasing HRT up to 50 h. Further increases in HRT above 50 h resulted in decreases in effluent ethanol concentration. The ethanol yield coefficient also increased with increasing HRT and reached the highest level of 0.54 gE g −1S at an HRT of 50 h. Due to cell settling to the bottom of the column, high fermentation rates were obtained in the lower section of the system. Therefore, the system can be operated with a height of 36 cm from the inlet to obtain high ethanol contents in the effluent with an HRT of 18 h.

Effects of feed sugar concentration on continuous ethanol fermentation of cheese whey powder solution (CWP)

Cheese whey powder (CWP) solution with different CWP or sugar concentrations was fermented to ethanol in a continuous fermenter using pure culture of Kluyveromyces marxianus (DSMZ 7239). Sugar concentration of the feed CWP solution varied between 55 and 200 g l −1 while the hydraulic residence time (HRT) was kept constant at 54 h. Ethanol formation, sugar utilization and biomass formation were investigated as functions of the feed sugar concentration. Percent sugar utilization and biomass concentrations decreased and the effluent sugar concentration increased with increasing feed sugar concentrations especially for the feed sugar contents above 100 g l −1. Ethanol concentration and productivity (DP) increased with increasing feed sugar up to 100 g l −1 and then decreased with further increases in the feed sugar content. The highest ethanol concentration (3.7%, v v −1) and productivity (0.54 gE l −1 h −1) were obtained with the feed sugar content of 100 g l −1 or 125 g l −1. The ethanol yield coefficient ( Y P/S) was also maximum (0.49 gE gS −1) when the feed sugar was between 100 and 125 g l −1. The growth yield coefficient ( Y X/S) decreased steadily from 0.123 to 0.063 gX gS −1 when the feed sugar increased from 55 to 200 g l −1 due to adverse effects of high sugar contents on yeast growth. The optimal feed sugar concentration maximizing the ethanol productivity and sugar utilization was between 100 and 125 g l −1 under the specified experimental conditions.

Comparison of yeast strains for batch ethanol fermentation of cheese?whey powder (CWP) solution

To test the suitability of cheese whey powder (CWP) solution for ethanol fermentation and to compare performances of different Kluyveromyces marxianus strains for ethanol fermentation from CWP solution. Batch ethanol fermentation of cheese whey (CW), CWP and lactose solutions with the same initial sugar contents were compared by using two different K. marxianus strains and the CWP solution was found to be the most suitable substrate. CWP solution was fermented to ethanol using three different yeast strains and DSMZ-7239 was found to be the most suitable one yielding the highest rate and extent (3.3%, v/v) of ethanol formation. CWP solution and K. marxianus strain of DSMZ-7239 were found to be more suitable for ethanol fermentation with the highest ethanol yield when compared with the other substrates and the yeast strains tested. CWP can be used as a concentrated form of CW for ethanol fermentations with considerable advantages.

Ethanol fermentation of cheese whey powder solution by repeated fed-batch operation

Ethanol fermentation of cheese whey powder (CWP) solution was realized in a fed-batch operated fermenter using the pure culture of Kluyveromyces marxianus (DSMZ 7239) at different feed CWP concentrations varying between 51 and 408 g l −1. Total sugar content of the feed varied between 25 and 200 g l −1 with a constant flow rate of 0.084 l h −1. Sugar utilization, ethanol formation and biomass growth were investigated as function of the feed sugar concentration in a five-cycle repeated fed-batch operation where the system reached the quasi steady-state. Variations of the growth and the product yield coefficients with the feed sugar concentration were quantified. The growth yield coefficient ( Y X/ S ) decreased with increasing feed sugar concentrations. The product yield coefficient ( Y P/ S ) was almost constant (0.54 ± 0.02 g EtOH g −1 S) for sugar concentrations between 25 and 150 g l −1, but decreased at the feed sugar concentration of 200 g l −1 due to high osmotic pressure at high sugar concentrations. The highest ethanol concentration (63 g l −1) and the productivity (5.3 g EtOH h −1) were obtained with a 125 g l −1 feed sugar concentration and sugar loading rate of 10.5 g S h −1.

Continuous ethanol fermentation of cheese whey powder solution: effects of hydraulic residence time

Continuous ethanol fermentation of cheese whey powder solution was realized using pure culture of Kluyveromyces marxianus (DSMZ 7239) at hydraulic residence times (HRT) between 12.5 and 60 h. Sugar utilization, ethanol and biomass formation were investigated as functions of HRT. Effluent sugar concentration decreased, but percent sugar utilization, ethanol and biomass concentrations increased with HRT. Ethanol productivity was maximum (0.745 gE l(-1)h(-1)) at an HRT of 43.2 h where the biomass productivity was almost minimum (0.18 gX l(-1) h(-1)). The ethanol yield coefficient was almost constant at 0.4 gE g(-1)S up to HRT of 43.2 h and the growth yield coefficient was minimum at HRT of 43.2 h. Kinetic models were developed and the constants were determined by using the experimental data.

Utilization of cheese whey powder (CWP) for ethanol fermentations: Effects of operating parameters

Cheese whey powder (CWP) solution was used for ethanol fermentation by Kluyveromyces marxianus NRRL-1195 in batch experiments. Effects of initial pH, CWP concentration and external nutrient (N, P) supplementation on ethanol formation rate and extent were investigated. The initial pH was varied between 3 and 7. The most suitable initial pH maximizing the final ethanol yield was found to be 5. Nutritional requirements of the organisms were investigated by supplementing the CWP solution with external nitrogen and phosphate sources. The rate and extent of ethanol formation did not increase with external nutrient addition indicating the fact that the nitrogen and phosphorous content of CWP was sufficient for ethanol fermentation. CWP concentration was varied between 50 and 300 g l −1 with total sugar concentrations between 25 and 150 g l −1. Final ethanol concentration and the rate of ethanol formation increased with increasing CWP concentration indicating no substrate or product inhibitions, but substrate limitations. The yield coefficient of ethanol varied between 0.35 and 0.54 g ethanol g sugar −1 and reached the theoretical level (0.54 g EtOH g sugar −1) at 300 g l −1 CWP concentration.