The Experts below are selected from a list of 177 Experts worldwide ranked by ideXlab platform

Peter Dunnill - One of the best experts on this subject based on the ideXlab platform.

  • Prediction of the pilot‐scale recovery of a recombinant yeast enzyme using integrated models
    Biotechnology and Bioengineering, 2001
    Co-Authors: E. G. Varga, Nigel J. Titchener-hooker, Peter Dunnill
    Abstract:

    This article describes the rapid prediction of recovery process performance for a new recombinant enzyme product on the basis of a broad portfolio of computer models and highly targeted experimentation. A process model for the recombinant system was generated by linking unit operation models in an integrated fashion, with required parameter estimation and physical property determination accomplished using data from scale-down studies. This enabled the generic modeling framework established for processing of a natural enzyme from bakers' yeast to be applied. An experimental study of the same operations at the pilot scale showed that the process model gave a conservative prediction of recombinant enzyme recovery. The model successfully captured interactions leading to a low overall product yield and indicated the need for further study of precipitate breakage in the feed zone of a Disc Stack Centrifuge in order to improve performance. The utility of scale-down units as an aid to fast model generation and the advantage of integrating computer modeling and scale-down studies to accelerate bioprocess development are highlighted.

  • The use of laboratory centrifugation studies to predict performance of industrial machines: Studies of shear-insensitive and shear-sensitive materials
    Biotechnology and Bioengineering, 2000
    Co-Authors: J. P. Maybury, Mike Hoare, Peter Dunnill
    Abstract:

    A method for using a bench-top Centrifuge is described in order to mimic the recovery performance of an industrial-scale Centrifuge, in this case a continuous-flow Disc Stack separator. Recovery performance was determined for polyvinyl acetate particles and for biological process streams of yeast cell debris and protein precipitates. Recovery of polyvinyl acetate particles was found to be well predicted for these robust particles. The laboratory centrifugation scale-down technique again predicted the performance of the Disc Stack Centrifuge for the recovery of yeast cell debris particles although there was some suggestion of over-prediction at high levels of debris recovery due to the nature of any cell debris aggregates present. The laboratory Centrifuge scale-down technique also proved to be an important investigative probe into the extent of shear-induced breakup of shear-sensitive protein precipitate aggregates during recovery in continuous high speed Centrifuges. Such breakup can lead to over 10-fold reduction in separator capacity.

  • The performance of a scaled down industrial Disc Stack Centrifuge with a reduced feed material requirement
    Bioprocess Engineering, 1998
    Co-Authors: J. P. Maybury, K. Mannweiler, MICHAEL HOARE, N. J. Titchener-hooker, Peter Dunnill
    Abstract:

    A method is described for the scale-down of a Disc Stack Centrifuge which reduces the number of separating Discs and also the liquid and solid hold-up of the Centrifuge bowl. This is to enable a reduced volume of process material to be used for study of clarification. Scale-down is achieved in stages using a series of interlocking inserts to suit particular applications. Maximum scale-down gives a 76% reduction in the separation area and a bowl volume reduction of 70%. Separation performance of the full Stack machine and scale-down variants is compared using the grade efficiency concept. Polyvinyl acetate and bakers' yeast homogenate particle suspensions are used for the comparison. The grade efficiency curves produced by the scale-down variants closely follow the curves for the full Stack machine. This resulted in supernatants of the same volume size distribution and concentration when using scale-down methodology to mimic the full scale operation.

  • Monitoring recombinant inclusion body recovery in an industrial Disc Stack Centrifuge
    Biotechnology and Bioengineering, 1994
    Co-Authors: K. Jin, Owen R.t. Thomas, Peter Dunnill
    Abstract:

    A simple and rapid spectrophotometric method for measuring recombinant inclusion body concentrations in the presence of Escherichia coli cell debris has been applied to monitoring the performance of an industrial Disc Stack Centrifuge. Turbidimetric measurements were made at two wavelengths, i.e., 600 nm and 420 nm, and the ratios of OD600nm/OD420nm related to the particle composition in suspension. The principle behind the technique is that inclusion body particles scatter light at 600 nm more effectively than do smaller cell debris particles when compared with the degree of light scatter at 420 nm. This technique may have broad potential application in developing an automatic monitoring and control system for industrial-scale inclusion body recovery. © 1994 John Wiley & Sons, Inc.

Giovanni Carlo Di Renzo - One of the best experts on this subject based on the ideXlab platform.

  • A comparison among innovative plants for high quality extra-virgin olive oil production.
    Journal of the Science of Food and Agriculture, 2020
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Attilio Matera, Giovanni Carlo Di Renzo
    Abstract:

    BACKGROUND The cleaning operation of extra-virgin olive oil (EVOO), subsequent to its extraction, is generally performed by means of a vertical Disc Stack Centrifuge separator causing qualitative damage due to increased oxidative alterations. However, previous works have demonstrated the great opportunity that settling represents in order to improve the EVOO quality performing the separation operation with minimal qualitative damage. RESULTS A new patented prototype device (ROTASED, RS) has been used in the cleaning operation of extra-virgin olive comparing physical and chemical characterization of EVOO after 48 h from extraction and after 180 days of shelf-life. In addition, the results have been compared with those obtained using an assisted sedimentation (AS) plant and an enhanced sedimentation plant by hydrocyclone (H) from previous authors' works, in order to assess the improvement of EVOO quality that could be attained with respect to the use of the vertical Disc Stack Centrifuge separator. CONCLUSION The results show that after 48 h of storage the tested patented prototype device seems to be preferable, however, after 180 days of storage, the difference between H and RS device results similar in terms of improvement of the final olive oil quality. In addition, the method of principal component analysis can be used to evaluate the suitability of an olive cv. in terms of quality of extracted oil. © 2020 Society of Chemical Industry.

  • Innovative plant for the separation of high quality virgin olive oil (VOO) at industrial scale
    Journal of Food Engineering, 2015
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Antonella Tauriello, Giovanni Carlo Di Renzo
    Abstract:

    Abstract Generally the virgin olive oil (VOO) requires a cleaning operation that is performed using a vertical Disc Stack Centrifuge representing the most important source of product oxidation. Natural settling represents an alternative to the oil/water separation but it results unsuitable for modern processes due to great amount of time required to perform the operation. In the present paper are reported the results of VOO cleaning through an enhanced sedimentation plant by hydrocyclone. Treatments have been compared by physical and chemical characterisation of VOO both after 48 h from extraction and after 180 days of shelf-life. The VOO cleaning by the enhanced sedimentation plant showed the capability to increase both processing capacity and VOO quality with respect to both VOO by vertical Disc Stack Centrifuge and by natural sedimentation plant. VOO analyzed after 48 h and after 6 months showed a lower oxidation level for oil by enhanced sedimentation, better quality and suitability for prolonged shelf-life than oil by Disc Stack Centrifuge. Moreover, even if Disc Stack Centrifuge plant produces olive oil that is much more clean than oil by enhanced sedimentation plant the latter shows an improved long-term stability. Principal component analysis shows that storage time effect on VOO is quantifiable as a decrease in colour level and an increase in oxidation level. The enhanced sedimentation plant produces an olive oil with the highest amount of antioxidants and pigments, whereas the natural sedimentation plant produces an olive oil with lesser antioxidants and pigments and higher value for K270.

  • Olive oil quality improvement using a natural sedimentation plant at industrial scale
    Biosystems Engineering, 2014
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Antonella Tauriello, Giovanni Carlo Di Renzo, Maurizio D'auria, Rocco Racioppi, Licia Viggiani
    Abstract:

    Olive oil extraction is mainly carried out using continuous extraction by decanter Centrifuge with efficiency of approximately 80–90%. After centrifugal extraction, olive oil is generally cleaned using a vertical Disc Stack Centrifuge separator, which is suspected of being the major cause of decreased final olive oil quality. Experiments were carried out at industrial scale to compare the olive oil properties after improved processes of sedimentation (Sedoil) or centrifugation (Cenoil) with respect to raw olive oil obtained at the decanter exit (Control). Peroxide, polyphenol, chlorophyll, carotenoid, turbidity and K232 average values were significantly different between Sedoil and Cenoil, which confirmed that the use of Disc Stack Centrifuges represents an important source of oxidative reactions. Analysis showed that storage time dramatically affects the oxidation level of the olive oil. All parameters used to monitor the oxidation level (i.e., free acidity, peroxide value and K232) increased after 180 d of storage, and the content of natural antioxidants and pigments decreased as expected. The residual presence of water during long-term storage represented the most important source of oxidation, and an effective cleaning operation is necessary to preserve oil quality during its storage life. The analyses performed using 1H and 13C NMR showed that Sedoil was more similar in composition to Control than to Cenoil. The use of sedimentation plant allows the employment of the disk Stack Centrifuge to be reduced improving both energy saving and the quality of clean olive oil.

  • Mild separation system for olive oil: quality evaluation and pilot plant design
    Journal of Agricultural Engineering, 2013
    Co-Authors: Francesco Genovese, Giuseppe Altieri, Giovanni Carlo Di Renzo, Antonella Tauriello
    Abstract:

    The entire process of olive oil extraction involves the breakage of olive fruits to obtain a paste, the kneading of the paste, a centrifugation, and a further cleaning, performed by a Disc Stack Centrifuge, to separate the residual water. In this research, in order to evaluate the effect of final centrifugal separation on olive oil quality and to both define and design the settings of a innovative separation system, olive oil was separated off from water using an accelerated separation process, tested in comparison with a Disc Centrifuge. The laboratory plant used for the trials was constituted by a twin cylindrical separator equipped with 4 variable frequency inverters, in order to regulate the fluid flow rates in the plant. Oil samples were collected during the trials to evaluate the influence of the proposed innovative process on oil quality; measuring some parameters as free acidity, peroxides (PV), specific extinction coefficients K232 and K270, chlorophylls , carotenoids, total polyphenols (POL) and turbidity. Results showed statistically significant differences (p-values

  • Mild separation system for olive oil: quality evaluation and pilot plant design
    PAGEPress Publications, 2013
    Co-Authors: Francesco Genovese, Giuseppe Altieri, Giovanni Carlo Di Renzo, Antonella Tauriello
    Abstract:

    The entire process of olive oil extraction involves the breakage of olive fruits to obtain a paste, the kneading of the paste, a centrifugation, and a further cleaning, performed by a Disc Stack Centrifuge, to separate the residual water. In this research, in order to evaluate the effect of final centrifugal separation on olive oil quality and to both define and design the settings of a innovative separation system, olive oil was separated off from water using an accelerated separation process, tested in comparison with a Disc Centrifuge. The laboratory plant used for the trials was constituted by a twin cylindrical separator equipped with 4 variable frequency inverters, in order to regulate the fluid flow rates in the plant. Oil samples were collected during the trials to evaluate the influence of the proposed innovative process on oil quality; measuring some parameters as free acidity, peroxides (PV), specific extinction coefficients K232 and K270, chlorophylls , carotenoids, total polyphenols (POL) and turbidity. Results showed statistically significant differences (p-values<0.05) in some parameters as POL, PV, and ultraviolet absorption K232 and K270

Giuseppe Altieri - One of the best experts on this subject based on the ideXlab platform.

  • A comparison among innovative plants for high quality extra-virgin olive oil production.
    Journal of the Science of Food and Agriculture, 2020
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Attilio Matera, Giovanni Carlo Di Renzo
    Abstract:

    BACKGROUND The cleaning operation of extra-virgin olive oil (EVOO), subsequent to its extraction, is generally performed by means of a vertical Disc Stack Centrifuge separator causing qualitative damage due to increased oxidative alterations. However, previous works have demonstrated the great opportunity that settling represents in order to improve the EVOO quality performing the separation operation with minimal qualitative damage. RESULTS A new patented prototype device (ROTASED, RS) has been used in the cleaning operation of extra-virgin olive comparing physical and chemical characterization of EVOO after 48 h from extraction and after 180 days of shelf-life. In addition, the results have been compared with those obtained using an assisted sedimentation (AS) plant and an enhanced sedimentation plant by hydrocyclone (H) from previous authors' works, in order to assess the improvement of EVOO quality that could be attained with respect to the use of the vertical Disc Stack Centrifuge separator. CONCLUSION The results show that after 48 h of storage the tested patented prototype device seems to be preferable, however, after 180 days of storage, the difference between H and RS device results similar in terms of improvement of the final olive oil quality. In addition, the method of principal component analysis can be used to evaluate the suitability of an olive cv. in terms of quality of extracted oil. © 2020 Society of Chemical Industry.

  • Innovative plant for the separation of high quality virgin olive oil (VOO) at industrial scale
    Journal of Food Engineering, 2015
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Antonella Tauriello, Giovanni Carlo Di Renzo
    Abstract:

    Abstract Generally the virgin olive oil (VOO) requires a cleaning operation that is performed using a vertical Disc Stack Centrifuge representing the most important source of product oxidation. Natural settling represents an alternative to the oil/water separation but it results unsuitable for modern processes due to great amount of time required to perform the operation. In the present paper are reported the results of VOO cleaning through an enhanced sedimentation plant by hydrocyclone. Treatments have been compared by physical and chemical characterisation of VOO both after 48 h from extraction and after 180 days of shelf-life. The VOO cleaning by the enhanced sedimentation plant showed the capability to increase both processing capacity and VOO quality with respect to both VOO by vertical Disc Stack Centrifuge and by natural sedimentation plant. VOO analyzed after 48 h and after 6 months showed a lower oxidation level for oil by enhanced sedimentation, better quality and suitability for prolonged shelf-life than oil by Disc Stack Centrifuge. Moreover, even if Disc Stack Centrifuge plant produces olive oil that is much more clean than oil by enhanced sedimentation plant the latter shows an improved long-term stability. Principal component analysis shows that storage time effect on VOO is quantifiable as a decrease in colour level and an increase in oxidation level. The enhanced sedimentation plant produces an olive oil with the highest amount of antioxidants and pigments, whereas the natural sedimentation plant produces an olive oil with lesser antioxidants and pigments and higher value for K270.

  • Olive oil quality improvement using a natural sedimentation plant at industrial scale
    Biosystems Engineering, 2014
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Antonella Tauriello, Giovanni Carlo Di Renzo, Maurizio D'auria, Rocco Racioppi, Licia Viggiani
    Abstract:

    Olive oil extraction is mainly carried out using continuous extraction by decanter Centrifuge with efficiency of approximately 80–90%. After centrifugal extraction, olive oil is generally cleaned using a vertical Disc Stack Centrifuge separator, which is suspected of being the major cause of decreased final olive oil quality. Experiments were carried out at industrial scale to compare the olive oil properties after improved processes of sedimentation (Sedoil) or centrifugation (Cenoil) with respect to raw olive oil obtained at the decanter exit (Control). Peroxide, polyphenol, chlorophyll, carotenoid, turbidity and K232 average values were significantly different between Sedoil and Cenoil, which confirmed that the use of Disc Stack Centrifuges represents an important source of oxidative reactions. Analysis showed that storage time dramatically affects the oxidation level of the olive oil. All parameters used to monitor the oxidation level (i.e., free acidity, peroxide value and K232) increased after 180 d of storage, and the content of natural antioxidants and pigments decreased as expected. The residual presence of water during long-term storage represented the most important source of oxidation, and an effective cleaning operation is necessary to preserve oil quality during its storage life. The analyses performed using 1H and 13C NMR showed that Sedoil was more similar in composition to Control than to Cenoil. The use of sedimentation plant allows the employment of the disk Stack Centrifuge to be reduced improving both energy saving and the quality of clean olive oil.

  • Mild separation system for olive oil: quality evaluation and pilot plant design
    Journal of Agricultural Engineering, 2013
    Co-Authors: Francesco Genovese, Giuseppe Altieri, Giovanni Carlo Di Renzo, Antonella Tauriello
    Abstract:

    The entire process of olive oil extraction involves the breakage of olive fruits to obtain a paste, the kneading of the paste, a centrifugation, and a further cleaning, performed by a Disc Stack Centrifuge, to separate the residual water. In this research, in order to evaluate the effect of final centrifugal separation on olive oil quality and to both define and design the settings of a innovative separation system, olive oil was separated off from water using an accelerated separation process, tested in comparison with a Disc Centrifuge. The laboratory plant used for the trials was constituted by a twin cylindrical separator equipped with 4 variable frequency inverters, in order to regulate the fluid flow rates in the plant. Oil samples were collected during the trials to evaluate the influence of the proposed innovative process on oil quality; measuring some parameters as free acidity, peroxides (PV), specific extinction coefficients K232 and K270, chlorophylls , carotenoids, total polyphenols (POL) and turbidity. Results showed statistically significant differences (p-values

  • Mild separation system for olive oil: quality evaluation and pilot plant design
    PAGEPress Publications, 2013
    Co-Authors: Francesco Genovese, Giuseppe Altieri, Giovanni Carlo Di Renzo, Antonella Tauriello
    Abstract:

    The entire process of olive oil extraction involves the breakage of olive fruits to obtain a paste, the kneading of the paste, a centrifugation, and a further cleaning, performed by a Disc Stack Centrifuge, to separate the residual water. In this research, in order to evaluate the effect of final centrifugal separation on olive oil quality and to both define and design the settings of a innovative separation system, olive oil was separated off from water using an accelerated separation process, tested in comparison with a Disc Centrifuge. The laboratory plant used for the trials was constituted by a twin cylindrical separator equipped with 4 variable frequency inverters, in order to regulate the fluid flow rates in the plant. Oil samples were collected during the trials to evaluate the influence of the proposed innovative process on oil quality; measuring some parameters as free acidity, peroxides (PV), specific extinction coefficients K232 and K270, chlorophylls , carotenoids, total polyphenols (POL) and turbidity. Results showed statistically significant differences (p-values<0.05) in some parameters as POL, PV, and ultraviolet absorption K232 and K270

E. G. Varga - One of the best experts on this subject based on the ideXlab platform.

  • Prediction of the pilot‐scale recovery of a recombinant yeast enzyme using integrated models
    Biotechnology and Bioengineering, 2001
    Co-Authors: E. G. Varga, Nigel J. Titchener-hooker, Peter Dunnill
    Abstract:

    This article describes the rapid prediction of recovery process performance for a new recombinant enzyme product on the basis of a broad portfolio of computer models and highly targeted experimentation. A process model for the recombinant system was generated by linking unit operation models in an integrated fashion, with required parameter estimation and physical property determination accomplished using data from scale-down studies. This enabled the generic modeling framework established for processing of a natural enzyme from bakers' yeast to be applied. An experimental study of the same operations at the pilot scale showed that the process model gave a conservative prediction of recombinant enzyme recovery. The model successfully captured interactions leading to a low overall product yield and indicated the need for further study of precipitate breakage in the feed zone of a Disc Stack Centrifuge in order to improve performance. The utility of scale-down units as an aid to fast model generation and the advantage of integrating computer modeling and scale-down studies to accelerate bioprocess development are highlighted.

  • Prediction of the pilot-scale recovery of a recombinant yeast enzyme using integrated models
    JOHN WILEY & SONS INC, 2001
    Co-Authors: E. G. Varga, N. J. Titchener-hooker, Dunnill P
    Abstract:

    This article describes the rapid prediction of recovery process performance for a new recombinant enzyme product on the basis of a broad portfolio of computer models and highly targeted experimentation. A process model for the recombinant system was generated by linking unit operation models in an integrated fashion, with required parameter estimation and physical property determination accomplished using data from scale-down studies. This enabled the generic modeling framework established for processing of a natural enzyme from bakers' yeast to be applied. An experimental study of the same operations at the pilot scale showed that the process model gave a conservative prediction of recombinant enzyme recovery. The model successfully captured interactions leading to a low overall product yield and indicated the need for further study of precipitate breakage in the feed zone of a Disc Stack Centrifuge in order to improve performance. The utility of scale-down units as an aid to fast model generation and the advantage of integrating computer modeling and scale-down studies to accelerate bioprocess development are highlighted. (C) 2001 John Wiley & Sons, Inc

  • Modelling of the downstream processing of a recombinant intracellular enzyme
    1997
    Co-Authors: E. G. Varga
    Abstract:

    This thesis examines the generation and verification of robust and predictive models for key unit operations in the downstream processing of a recombinant intracellular enzyme. Computer models are becoming increasingly used in the biotechnology industry to assess process feasibility, ensure appropriate specification and achieve efficient operation of bioprocesses. With increasing pressure to bring bioproducts to market in the shortest possible time and at low cost, it is essential that these models can be generated early in the development cycle with a minimum of time and expense. Regulatory concerns over the use of recombinant systems also require a highly consistent product and a large degree of confidence in any final design. Models must therefore be verified against real process data in order to demonstrate and improve their validity. The specific operations under study were cell disruption by high pressure homogenisation, enzyme fractionation and concentration by ammonium sulphate precipitation, and cell harvesting, debris removal and precipitate separation by Disc Stack centrifugation. Existing models based on the recovery of alcohol dehydrogenase (ADH) from natural bakers' yeast were applied to the processing of a protein engineered form of the enzyme (pe-ADH) and their validity assessed by comparison with experimental data obtained from small amounts of fermented recombinant material. Differences were observed in the processing of the natural and protein engineered enzyme and, although parameter re-evaluation was generally required to maintain model accuracy, the models were found to be generic in nature. Individual unit models were then arranged and linked in a modular fashion to produce a whole process model. Verification of the process model based on recombinant system parameters against pilot-scale data showed sufficient accuracy for use in feasibility studies (±30%). The inability to describe precipitant breakage in the Disc Stack Centrifuge feed-zone was the major source of model inaccuracy. The work highlighted the utility of scale-down systems as an aid to rapid and cost- effective model development. The importance of experimental verification in order to provide confidence in model accuracy and scalability was stressed, as was the need for modelling to be an integrated activity during bioprocess development.

Francesco Genovese - One of the best experts on this subject based on the ideXlab platform.

  • A comparison among innovative plants for high quality extra-virgin olive oil production.
    Journal of the Science of Food and Agriculture, 2020
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Attilio Matera, Giovanni Carlo Di Renzo
    Abstract:

    BACKGROUND The cleaning operation of extra-virgin olive oil (EVOO), subsequent to its extraction, is generally performed by means of a vertical Disc Stack Centrifuge separator causing qualitative damage due to increased oxidative alterations. However, previous works have demonstrated the great opportunity that settling represents in order to improve the EVOO quality performing the separation operation with minimal qualitative damage. RESULTS A new patented prototype device (ROTASED, RS) has been used in the cleaning operation of extra-virgin olive comparing physical and chemical characterization of EVOO after 48 h from extraction and after 180 days of shelf-life. In addition, the results have been compared with those obtained using an assisted sedimentation (AS) plant and an enhanced sedimentation plant by hydrocyclone (H) from previous authors' works, in order to assess the improvement of EVOO quality that could be attained with respect to the use of the vertical Disc Stack Centrifuge separator. CONCLUSION The results show that after 48 h of storage the tested patented prototype device seems to be preferable, however, after 180 days of storage, the difference between H and RS device results similar in terms of improvement of the final olive oil quality. In addition, the method of principal component analysis can be used to evaluate the suitability of an olive cv. in terms of quality of extracted oil. © 2020 Society of Chemical Industry.

  • Innovative plant for the separation of high quality virgin olive oil (VOO) at industrial scale
    Journal of Food Engineering, 2015
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Antonella Tauriello, Giovanni Carlo Di Renzo
    Abstract:

    Abstract Generally the virgin olive oil (VOO) requires a cleaning operation that is performed using a vertical Disc Stack Centrifuge representing the most important source of product oxidation. Natural settling represents an alternative to the oil/water separation but it results unsuitable for modern processes due to great amount of time required to perform the operation. In the present paper are reported the results of VOO cleaning through an enhanced sedimentation plant by hydrocyclone. Treatments have been compared by physical and chemical characterisation of VOO both after 48 h from extraction and after 180 days of shelf-life. The VOO cleaning by the enhanced sedimentation plant showed the capability to increase both processing capacity and VOO quality with respect to both VOO by vertical Disc Stack Centrifuge and by natural sedimentation plant. VOO analyzed after 48 h and after 6 months showed a lower oxidation level for oil by enhanced sedimentation, better quality and suitability for prolonged shelf-life than oil by Disc Stack Centrifuge. Moreover, even if Disc Stack Centrifuge plant produces olive oil that is much more clean than oil by enhanced sedimentation plant the latter shows an improved long-term stability. Principal component analysis shows that storage time effect on VOO is quantifiable as a decrease in colour level and an increase in oxidation level. The enhanced sedimentation plant produces an olive oil with the highest amount of antioxidants and pigments, whereas the natural sedimentation plant produces an olive oil with lesser antioxidants and pigments and higher value for K270.

  • Olive oil quality improvement using a natural sedimentation plant at industrial scale
    Biosystems Engineering, 2014
    Co-Authors: Giuseppe Altieri, Francesco Genovese, Antonella Tauriello, Giovanni Carlo Di Renzo, Maurizio D'auria, Rocco Racioppi, Licia Viggiani
    Abstract:

    Olive oil extraction is mainly carried out using continuous extraction by decanter Centrifuge with efficiency of approximately 80–90%. After centrifugal extraction, olive oil is generally cleaned using a vertical Disc Stack Centrifuge separator, which is suspected of being the major cause of decreased final olive oil quality. Experiments were carried out at industrial scale to compare the olive oil properties after improved processes of sedimentation (Sedoil) or centrifugation (Cenoil) with respect to raw olive oil obtained at the decanter exit (Control). Peroxide, polyphenol, chlorophyll, carotenoid, turbidity and K232 average values were significantly different between Sedoil and Cenoil, which confirmed that the use of Disc Stack Centrifuges represents an important source of oxidative reactions. Analysis showed that storage time dramatically affects the oxidation level of the olive oil. All parameters used to monitor the oxidation level (i.e., free acidity, peroxide value and K232) increased after 180 d of storage, and the content of natural antioxidants and pigments decreased as expected. The residual presence of water during long-term storage represented the most important source of oxidation, and an effective cleaning operation is necessary to preserve oil quality during its storage life. The analyses performed using 1H and 13C NMR showed that Sedoil was more similar in composition to Control than to Cenoil. The use of sedimentation plant allows the employment of the disk Stack Centrifuge to be reduced improving both energy saving and the quality of clean olive oil.

  • Mild separation system for olive oil: quality evaluation and pilot plant design
    Journal of Agricultural Engineering, 2013
    Co-Authors: Francesco Genovese, Giuseppe Altieri, Giovanni Carlo Di Renzo, Antonella Tauriello
    Abstract:

    The entire process of olive oil extraction involves the breakage of olive fruits to obtain a paste, the kneading of the paste, a centrifugation, and a further cleaning, performed by a Disc Stack Centrifuge, to separate the residual water. In this research, in order to evaluate the effect of final centrifugal separation on olive oil quality and to both define and design the settings of a innovative separation system, olive oil was separated off from water using an accelerated separation process, tested in comparison with a Disc Centrifuge. The laboratory plant used for the trials was constituted by a twin cylindrical separator equipped with 4 variable frequency inverters, in order to regulate the fluid flow rates in the plant. Oil samples were collected during the trials to evaluate the influence of the proposed innovative process on oil quality; measuring some parameters as free acidity, peroxides (PV), specific extinction coefficients K232 and K270, chlorophylls , carotenoids, total polyphenols (POL) and turbidity. Results showed statistically significant differences (p-values

  • Mild separation system for olive oil: quality evaluation and pilot plant design
    PAGEPress Publications, 2013
    Co-Authors: Francesco Genovese, Giuseppe Altieri, Giovanni Carlo Di Renzo, Antonella Tauriello
    Abstract:

    The entire process of olive oil extraction involves the breakage of olive fruits to obtain a paste, the kneading of the paste, a centrifugation, and a further cleaning, performed by a Disc Stack Centrifuge, to separate the residual water. In this research, in order to evaluate the effect of final centrifugal separation on olive oil quality and to both define and design the settings of a innovative separation system, olive oil was separated off from water using an accelerated separation process, tested in comparison with a Disc Centrifuge. The laboratory plant used for the trials was constituted by a twin cylindrical separator equipped with 4 variable frequency inverters, in order to regulate the fluid flow rates in the plant. Oil samples were collected during the trials to evaluate the influence of the proposed innovative process on oil quality; measuring some parameters as free acidity, peroxides (PV), specific extinction coefficients K232 and K270, chlorophylls , carotenoids, total polyphenols (POL) and turbidity. Results showed statistically significant differences (p-values<0.05) in some parameters as POL, PV, and ultraviolet absorption K232 and K270