Improved Ultrafiltration for Color Reduction and Stabilization of Apple Juice

Gökmen, Vural; Borneman, Zandrie; Nijhuis, Herry H.

doi:10.1111/j.1365-2621.1998.tb15773.x

Cited by 48 publications

(30 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Laccasetreated and further ultrafiltered pomegranate juice showed a 32% increase in its clarity. Our results are in agreement with those of Gokmen et al [20].…”

Section: Enzyme Influence On the Permeate Flux And The Quality Of Clasupporting

confidence: 94%

“…However, laccase-UF-treated and only UFtreated pomegranate juice showed the same decrease in their color (35%) compared with untreated samples (table IV). These results are in agreement with other authors [5,20]. For example, Gokmen et al reported that custom membranes caused a notable decolorization in both laccase-treated and control samples of apple juice (reduction in color varied from 28% to 45%) [20].…”

Section: Enzyme Influence On the Permeate Flux And The Quality Of Clasupporting

confidence: 92%

“…These results are in agreement with other authors [5,20]. For example, Gokmen et al reported that custom membranes caused a notable decolorization in both laccase-treated and control samples of apple juice (reduction in color varied from 28% to 45%) [20]. The color of the samples was increased by 90% [5].…”

Section: Enzyme Influence On the Permeate Flux And The Quality Of Clasupporting

confidence: 92%

“…These compounds could be discarded by centrifugation. On the other hand, low-molecularweight phenols (oligomers) remain in the supernatant and could lead to a darkening of the juice color which could easily be removed by membrane filtration [5,20].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Clarification of pomegranate juice by ultrafiltration: study of juice quality and of the fouling mechanism

Baklouti

Ellouze-Ghorbel²,

Mokni³

2012

Fruits

View full text Add to dashboard Cite

-Introduction. Ultrafiltration (UF) is a single-unit operation for the clarification and fining of fruit juices. The purpose of the UF is to remove suspended solids as well as haze-inducing and turbidity-causing substances to obtain a clear juice during storage. Specifically, the polymerization of phenolic compounds and their interaction with other components (e.g., proteins) could cause a haze complex and turbidity in fruit juices, which can foul the ultrafiltration membrane. Materials and methods. Fresh pomegranate juice was clarified by the ultrafiltration process on a laboratory scale. In experimental tests performed according to the total recycle and the batch concentration mode, the effects of transmembrane pressure (TMP) and enzyme pre-treatment on permeation flux and quality of juice were studied. Results. With the total recycle mode, the effect of TMP on the color and clarity of clarified pomegranate juice was significant. The initial color of the raw pomegranate juice was reduced from 74% to 33% and the clarity decreased from 77% to 42% by UF when the TMP increased from (1 to 3.6) bar. Total phenolic rejection decreased from 45% to 21% when the TMP rose from (1 to 2) bar and remained constant above this value. With the batch concentration mode at TMP = 2 bar and velocity 1 m·s -1 , the enzymatic treatment (5 U·mL -1 , 300 min, T = 20°C) of pomegranate juice provided the highest permeate flux, a decrease in total phenolics of 50% and an increased clarity of 30%. Fouling of the UF membrane during pomegranate juice processing is mainly due to the retention of polyphenols and/or proteins; thus, several blocking mechanisms were studied, using a recently developed membrane-fouling model. Analysis revealed that the membrane separation process was controlled by the gel layer mechanism of raw pomegranate juice and complete pore blocking mechanism with enzymatic pretreatment. Tunisia / Punica granatum / fruit juices / clarifying / ultrafiltration / phenolic compounds / membranes / fouling / processing / laccase Clarification du jus de grenade par ultrafiltration : étude de la qualité du jus et du mécanisme de colmatage.Résumé -Introduction.L'ultrafiltration (UF) est un procédé simple pour la clarification et pour l'affinage de jus de fruits. Son objectif est d'éliminer les matières en suspension ainsi que les substances induisant trouble et turbidité pendant son stockage. Plus précisément, la polymérisation des composés phénoliques et leur interaction avec d'autres composants (des protéines, par exemple) pourraient causer du trouble et de la turbidité dans les jus de fruits, conduisant au colmatage de la membrane d'ultrafiltration. Matériel et méthodes. Un jus de grenade frais a été clarifié par ultrafiltration. Les essais expérimentaux ont été effectués en mode de recyclage total ou en batch par renvoi du retentât dans la cuve d'alimentation. Les effets de la pression transmembranaire (PTM) et d'un prétraitement enzymatique sur le flux de perméation et la qualité des jus ont été étudiés. Résultats. Ave...

show abstract

“…Laccasetreated and further ultrafiltered pomegranate juice showed a 32% increase in its clarity. Our results are in agreement with those of Gokmen et al [20].…”

Section: Enzyme Influence On the Permeate Flux And The Quality Of Clasupporting

confidence: 94%

Section: Enzyme Influence On the Permeate Flux And The Quality Of Clasupporting

confidence: 92%

Section: Enzyme Influence On the Permeate Flux And The Quality Of Clasupporting

confidence: 92%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Clarification of pomegranate juice by ultrafiltration: study of juice quality and of the fouling mechanism

Baklouti

Ellouze-Ghorbel²,

Mokni³

2012

Fruits

View full text Add to dashboard Cite

show abstract

“…In addition, a substrate spectrum of laccases can be expanded in the presence of a mediator. Thus, laccases are used in many industrial fields, such as pulp bleaching in the paper industry [8], textile dye decolorization [9], detoxification of environmental pollutants [10], and beverage industry [11].…”

Section: Introductionmentioning

confidence: 99%

Essential Role of the N- and C-terminals of Laccase from Pleurotus florida on the Laccase Activity and Stability

Zhou

Shi

et al. 2014

Appl Biochem Biotechnol

View full text Add to dashboard Cite

POXA1b is the most thermostable laccase isoenzyme from Pleurotus ostreatus. POXA1b is remarkably stable at alkaline pH (the t1/2 at pH 10 was 30 days), and its C-terminal affects its catalytic and stability properties. We cloned POXA1c from P. florida, which showed 99 % identity with POXA1b. POXA1c was functionally expressed in Pichia pastoris. The functions of the N and C termini of POXA1c were investigated using site-directed mutagenesis. Compared with POXA1c, the N-terminal R5V site effectively increased the specific activities for 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and guaiacol by 2- and 3.5-fold, respectively. A C-terminal truncated mutant, POXA1c△13, also increased the specific activities for ABTS and guaiacol by 2.3- and 3.4-fold, respectively. A double mutant, POXA1cΔ13-R5V, combined the R5V and △13 effects. The specific activity of this double mutant for ABTS was 1,321 U/mg, which indicated a 4-fold increase compared with the wild type. The role of residue V5 on laccase catalytic properties was also observed for laccases from Trametes versicolor and Rigidoporus lignosus. The specific activities of the V5R of the laccases from T. versicolor and R. lignosus were half of that of the wild type. The pH and thermal stability analysis of POXA1c and its mutants showed that the enzymes were remarkably stable because they showed 63 % residual activity after incubation for 108 h at 30 °C over a pH range of 4.5 to 9.0. Similar results were observed for POXA1cΔ13-R5V. POXA1cΔ13-R5V can be widely used in industrial biotechnology because of its excellent catalytic properties.

show abstract

Membrane Contactors in Integrated Processes for Fruit‐Juice Processing

Cassano

Drioli

2010

Membrane Technology

View full text Add to dashboard Cite

Improved Ultrafiltration for Color Reduction and Stabilization of Apple Juice

Cited by 48 publications

References 12 publications

Clarification of pomegranate juice by ultrafiltration: study of juice quality and of the fouling mechanism

Clarification of pomegranate juice by ultrafiltration: study of juice quality and of the fouling mechanism

Essential Role of the N- and C-terminals of Laccase from Pleurotus florida on the Laccase Activity and Stability

Membrane Contactors in Integrated Processes for Fruit‐Juice Processing

Contact Info

Product

Resources

About