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Rosnah Shamsudin - One of the best experts on this subject based on the ideXlab platform.

  • effect of repetitive ultraviolet irradiation on the physico chemical properties and microbial stability of Pineapple Juice
    Innovative Food Science and Emerging Technologies, 2014
    Co-Authors: Rosnah Shamsudin, Noranizan Mohd Adzahan, Yap Pui Yee, Atikah Mansor
    Abstract:

    Abstract The study aims to investigate the effect of repetitive ultraviolet irradiation (UV–UV) and the combination effect with dimethyl dicarbonate (UV–DMDC–UV) on the physico-chemical properties and microbiological stability of Pineapple Juice. UV dosages of 10.76 mJ/cm 2 percycle and 250 ppm of DMDC were used. There was a significant decrease in turbidity, total phenolic and vitamin C in the treated Juices. The UV–UV reported a significant reduction of 1.91 log CFU/ml in total plate count and 1.4 log CFU/ml in yeast and mould. Post addition of DMDC into the UV irradiated Juice (UV–UV–DMDC) showed reductions of 2.61 log CFU/ml for TPC and 4.87 log CFU/ml for YM. This study demonstrated the effectiveness of UV irradiation in preserving the nutritional quality and the addition of DMDC can have a combination effect with the UV irradiation of Juice in terms of microbial reduction. However, the treatments were not sufficient to achieve adequate microbial reduction as required by the FDA. Industrial relevance Dimethyl dicarbonate (DMDC) is one of the effective anti-microbial agents that can control a wide range of microorganisms which includes Escherichia coli 0157:H7 and yeast. The effect of dimethyl dicarbonate (DMDC) in reducing microbial counts was significant in this study. According to Threlfall and Morris (2002) , DMDC is used to prevent fermentation in excessive yeast contamination in wine production. Moreover, Halim et al. (2012) stated that DMDC has shown promising results for microbial inactivation of fruit Juices in a preliminary study in lab. Therefore, combination effect with additives (DMDC) may be able to increase the efficiency of the UV irradiation for microbial reduction in Juice and longer the shelf life of Juice.

  • rheological properties of ultraviolet irradiated and thermally pasteurized yankee Pineapple Juice
    Journal of Food Engineering, 2013
    Co-Authors: Rosnah Shamsudin, Noranizan Mohd Adzahan, Chia Su Ling, Wan Ramli Wan Daud
    Abstract:

    Abstract The rheological behaviour of Yankee Pineapple Juice was examined for the effect of ultraviolet (UV) irradiation (53.42 mJ/cm 2 ) and compared with untreated Juice and a thermally pasteurized (80 °C for 10 min) Juice. A rheological test was performed on all types of Juice in the temperature range 5 °C to 25 °C using a concentric cylinder rheometer at a shear rate range of 10–290 s −1 . The comparative analysis found that the best flow curves were described by the Bingham model with an initial shear stress. The entangled pulps in the Juices prevented free flow at zero shear rate. There was no significant variation between the plastic viscosities of the untreated and UV-irradiated Juice at all temperatures. The activation energy ( E a ) of the untreated, UV-irradiated and thermally pasteurized Juice was 6.80, 8.19 and 8.50 kJ/mol respectively.

  • rheological properties of josapine Pineapple Juice at different stages of maturity
    International Journal of Food Science and Technology, 2009
    Co-Authors: Rosnah Shamsudin, Wan Ramli Wan Daud, Mohd Sobri Takrif, Osman Hassan, Coskan Ilicali
    Abstract:

    The rheological behaviour of Josapine Pineapple Juice with at various maturity stages was studied at a wide range of temperature (5–65 °C) and concentration (4–14 °Brix) using a rotational rheometer as the measuring system. The results show that josapine Pineapples Juice demonstrated a Newtonian behavior and is influenced by maturity stage, temperature and concentration. The Arrhenius typed equation successfully describe the effect of temperature on the viscosity, on the other hand, the effect of concentration can be described better using exponential equation. Finally, an equation describing the combined effect of temperature and concentration on viscosity at different stages of maturity was successfully developed.

Wirote Youravong - One of the best experts on this subject based on the ideXlab platform.

  • storage quality of Pineapple Juice non thermally pasteurized and clarified by microfiltration
    Journal of Food Engineering, 2013
    Co-Authors: Aporn Laorko, Sasitorn Tongchitpakdee, Wirote Youravong
    Abstract:

    Abstract Microfiltration (MF) is classified as a non-thermal process for the fruit Juice industry. It could provide a better preservation of the phytochemical property and flavor of the Juice. This work aimed to study the stability of phytochemical properties including vitamin C, total phenolic content, antioxidant capacity (2-Diphenly-1-picrylhydrazyl: DPPH, free radical scavenging capacity and Oxygen Radical Absorbance Capacity: ORAC assays), microbial and chemical–physical (color, browning index, pH and total soluble solid) properties of MF-clarified Pineapple Juice during storage at various temperatures (i.e. 4, 27, and 37 °C). The Juices were clarified by microfiltration using hollow fiber module. The results showed that most of the phytochemical properties and soluble components were retained in the Juice after microfiltration. No microbial growth was detected after 6 months of storage. The storage time and temperature did not affect total soluble solids and pH (P > 0.05). The color (L*) of clarified Juice stored at 4 °C was lighter than the Juices stored at higher temperature levels (P

  • effect of gas sparging on flux enhancement and phytochemical properties of clarified Pineapple Juice by microfiltration
    Separation and Purification Technology, 2011
    Co-Authors: Aporn Laorko, Sasitorn Tongchitpakdee, Wirote Youravong
    Abstract:

    Abstract Membrane fouling is a major obstacle in the application of microfiltration. Several techniques have been proposed to enhance the permeate flux during microfiltration. Gas sparging is a hydrodynamic method for improving the performance of the membrane process. In this study, a 0.2 μm hollow fiber microfiltration membrane was used to study the effect of cross flow velocity (CFV) and gas injection factor ( e ) on the critical and limiting flux during microfiltration of Pineapple Juice. In addition, the phytochemical properties of clarified Juice were investigated. In the absence of gas sparging, the critical and limiting flux increased as the CFV or shear stress number increased. The use of gas sparging led to a remarkable improvement in both the critical and limiting flux but it was more effective at the lower CFV (1.5 m s −1 ), compared to those at higher CFV (2.0 and 2.5 m s −1 ). When the gas injection factor was applied at 0.15, 0.25 and 0.35 with a CFV of 1.5 m s −1 , the enhancement of 55.6%, 75.5% and 128.2% was achieved for critical flux, while 65.8%, 69.7% and 95.2% was achieved for limiting flux, respectively. The results also indicated that the use of gas sparging was an effective method to reduce reversible fouling and external irreversible fouling rather than internal irreversible fouling. In addition, the CFV and gas sparging did not affect pH, total soluble solids, colour, total phenolic content and the antioxidant property of the clarified Juice. The l -ascorbic acid and total vitamin C were significantly decreased when the higher CFV and high gas injection factor were applied. The results also indicated that the use of gas sparging with low CFV was beneficial for flux enhancement while most of the phytochemical properties of the clarified Juice was preserved.

  • effect of membrane property and operating conditions on phytochemical properties and permeate flux during clarification of Pineapple Juice
    Journal of Food Engineering, 2010
    Co-Authors: Aporn Laorko, Sasitorn Tongchitpakdee, Suphitchaya Chantachum, Wirote Youravong
    Abstract:

    Abstract The effects of membrane property on the permeate flux, membrane fouling and quality of clarified Pineapple Juice were studied. Both microfiltration (membrane pore size of 0.1 and 0.2 μm) and ultrafiltration (membrane molecular weight cut-off (MWCO) of 30 and 100 kDa) membranes were employed. Membrane filtration did not have significant effects on the pH, reducing sugar and acidity of clarified Juice whereas the suspended solids and microorganism were completely removed. The 0.2 μm membrane gave the highest permeate flux, total vitamin C content, total phenolic content and antioxidant capacity as well as the highest value of irreversible fouling. Based on these results, the membrane with pore size of 0.2 μm was considered to be the most suitable membrane for the clarification of Pineapple Juice. The optimum operating conditions for the clarification Pineapple Juice by membrane filtration was a cross-flow velocity of 3.4 ms−1 and transmembrane pressure (TMP) of 0.7 bar. An average flux of about 37 lm−2 h−1 was obtained during the microfiltration of Pineapple Juice under the optimum conditions using batch concentration mode.

Wan Ramli Wan Daud - One of the best experts on this subject based on the ideXlab platform.

  • rheological properties of ultraviolet irradiated and thermally pasteurized yankee Pineapple Juice
    Journal of Food Engineering, 2013
    Co-Authors: Rosnah Shamsudin, Noranizan Mohd Adzahan, Chia Su Ling, Wan Ramli Wan Daud
    Abstract:

    Abstract The rheological behaviour of Yankee Pineapple Juice was examined for the effect of ultraviolet (UV) irradiation (53.42 mJ/cm 2 ) and compared with untreated Juice and a thermally pasteurized (80 °C for 10 min) Juice. A rheological test was performed on all types of Juice in the temperature range 5 °C to 25 °C using a concentric cylinder rheometer at a shear rate range of 10–290 s −1 . The comparative analysis found that the best flow curves were described by the Bingham model with an initial shear stress. The entangled pulps in the Juices prevented free flow at zero shear rate. There was no significant variation between the plastic viscosities of the untreated and UV-irradiated Juice at all temperatures. The activation energy ( E a ) of the untreated, UV-irradiated and thermally pasteurized Juice was 6.80, 8.19 and 8.50 kJ/mol respectively.

  • rheological properties of josapine Pineapple Juice at different stages of maturity
    International Journal of Food Science and Technology, 2009
    Co-Authors: Rosnah Shamsudin, Wan Ramli Wan Daud, Mohd Sobri Takrif, Osman Hassan, Coskan Ilicali
    Abstract:

    The rheological behaviour of Josapine Pineapple Juice with at various maturity stages was studied at a wide range of temperature (5–65 °C) and concentration (4–14 °Brix) using a rotational rheometer as the measuring system. The results show that josapine Pineapples Juice demonstrated a Newtonian behavior and is influenced by maturity stage, temperature and concentration. The Arrhenius typed equation successfully describe the effect of temperature on the viscosity, on the other hand, the effect of concentration can be described better using exponential equation. Finally, an equation describing the combined effect of temperature and concentration on viscosity at different stages of maturity was successfully developed.

Aporn Laorko - One of the best experts on this subject based on the ideXlab platform.

  • storage quality of Pineapple Juice non thermally pasteurized and clarified by microfiltration
    Journal of Food Engineering, 2013
    Co-Authors: Aporn Laorko, Sasitorn Tongchitpakdee, Wirote Youravong
    Abstract:

    Abstract Microfiltration (MF) is classified as a non-thermal process for the fruit Juice industry. It could provide a better preservation of the phytochemical property and flavor of the Juice. This work aimed to study the stability of phytochemical properties including vitamin C, total phenolic content, antioxidant capacity (2-Diphenly-1-picrylhydrazyl: DPPH, free radical scavenging capacity and Oxygen Radical Absorbance Capacity: ORAC assays), microbial and chemical–physical (color, browning index, pH and total soluble solid) properties of MF-clarified Pineapple Juice during storage at various temperatures (i.e. 4, 27, and 37 °C). The Juices were clarified by microfiltration using hollow fiber module. The results showed that most of the phytochemical properties and soluble components were retained in the Juice after microfiltration. No microbial growth was detected after 6 months of storage. The storage time and temperature did not affect total soluble solids and pH (P > 0.05). The color (L*) of clarified Juice stored at 4 °C was lighter than the Juices stored at higher temperature levels (P

  • effect of gas sparging on flux enhancement and phytochemical properties of clarified Pineapple Juice by microfiltration
    Separation and Purification Technology, 2011
    Co-Authors: Aporn Laorko, Sasitorn Tongchitpakdee, Wirote Youravong
    Abstract:

    Abstract Membrane fouling is a major obstacle in the application of microfiltration. Several techniques have been proposed to enhance the permeate flux during microfiltration. Gas sparging is a hydrodynamic method for improving the performance of the membrane process. In this study, a 0.2 μm hollow fiber microfiltration membrane was used to study the effect of cross flow velocity (CFV) and gas injection factor ( e ) on the critical and limiting flux during microfiltration of Pineapple Juice. In addition, the phytochemical properties of clarified Juice were investigated. In the absence of gas sparging, the critical and limiting flux increased as the CFV or shear stress number increased. The use of gas sparging led to a remarkable improvement in both the critical and limiting flux but it was more effective at the lower CFV (1.5 m s −1 ), compared to those at higher CFV (2.0 and 2.5 m s −1 ). When the gas injection factor was applied at 0.15, 0.25 and 0.35 with a CFV of 1.5 m s −1 , the enhancement of 55.6%, 75.5% and 128.2% was achieved for critical flux, while 65.8%, 69.7% and 95.2% was achieved for limiting flux, respectively. The results also indicated that the use of gas sparging was an effective method to reduce reversible fouling and external irreversible fouling rather than internal irreversible fouling. In addition, the CFV and gas sparging did not affect pH, total soluble solids, colour, total phenolic content and the antioxidant property of the clarified Juice. The l -ascorbic acid and total vitamin C were significantly decreased when the higher CFV and high gas injection factor were applied. The results also indicated that the use of gas sparging with low CFV was beneficial for flux enhancement while most of the phytochemical properties of the clarified Juice was preserved.

  • effect of membrane property and operating conditions on phytochemical properties and permeate flux during clarification of Pineapple Juice
    Journal of Food Engineering, 2010
    Co-Authors: Aporn Laorko, Sasitorn Tongchitpakdee, Suphitchaya Chantachum, Wirote Youravong
    Abstract:

    Abstract The effects of membrane property on the permeate flux, membrane fouling and quality of clarified Pineapple Juice were studied. Both microfiltration (membrane pore size of 0.1 and 0.2 μm) and ultrafiltration (membrane molecular weight cut-off (MWCO) of 30 and 100 kDa) membranes were employed. Membrane filtration did not have significant effects on the pH, reducing sugar and acidity of clarified Juice whereas the suspended solids and microorganism were completely removed. The 0.2 μm membrane gave the highest permeate flux, total vitamin C content, total phenolic content and antioxidant capacity as well as the highest value of irreversible fouling. Based on these results, the membrane with pore size of 0.2 μm was considered to be the most suitable membrane for the clarification of Pineapple Juice. The optimum operating conditions for the clarification Pineapple Juice by membrane filtration was a cross-flow velocity of 3.4 ms−1 and transmembrane pressure (TMP) of 0.7 bar. An average flux of about 37 lm−2 h−1 was obtained during the microfiltration of Pineapple Juice under the optimum conditions using batch concentration mode.

Gláucia Maria Falcão Aragão - One of the best experts on this subject based on the ideXlab platform.

  • GROWTH OF BYSSOCHLAMYS NIVEA IN Pineapple Juice UNDER THE EFFECT OF WATER ACTIVITY AND ASCOSPORE AGE
    2016
    Co-Authors: M. Zimmermann, S. Miorelli, P R Massaguer, Gláucia Maria Falcão Aragão
    Abstract:

    The study of thermal resistant mould, including Byssochlamys nivea, is of extreme importance since it has been associated with fruit and fruit products. The aim of this work is to analyze the influence of water activity (aw) and ascospore age (I) on the growth of Byssochlamys nivea in Pineapple Juice. Mold growth was carried out under different conditions of water activity (aw) (0.99, 0.96, 0.95, 0.93, 0.90) and ascospore ag

  • Growth of Byssochlamys Nivea in Pineapple Juice under the effect of water activity and ascospore age
    Brazilian Journal of Microbiology, 2011
    Co-Authors: M. Zimmermann, S. Miorelli, P R Massaguer, Gláucia Maria Falcão Aragão
    Abstract:

    The study of thermal resistant mould, including Byssochlamys nivea, is of extreme importance since it has been associated with fruit and fruit products. The aim of this work is to analyze the influence of water activity (aw) and ascospore age (I) on the growth of Byssochlamys nivea in Pineapple Juice. Mold growth was carried out under different conditions of water activity (aw) (0.99, 0.96, 0.95, 0.93, 0.90) and ascospore age (I) (30, 51, 60, 69, 90 days). Growth parameters as length of adaptation phase (λ), maximum specific growth rate (µmax) and maximum diameter reached by the colony (λ) were obtained through the fit of the Modified Gompertz model to experimental data (measuring radial colony diameter). Statistica 6.0 was used for statistical analyses (significance level α=0.05). The results obtained clearly showed that water activity is statistically significant and that it influences all growth parameters, while ascospore age does not have any statistically significant influence on growth parameters. Also, these data showed that by increasing aw from 0.90 to 0.99, the λ value substantially decreased, while µmax and λ values rose. The data contributed for the understanding of the behavior of B. nivea in Pineapple Juice. Therefore, it provided mathematical models that can well predict growth parameters, also helping on microbiological control and products' shelf life determination.

  • GROWTH OF BYSSOCHLAMYS NIVEA IN Pineapple Juice UNDER THE EFFECT OF WATER ACTIVITY AND ASCOSPORE AGE
    Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology], 2011
    Co-Authors: M. Zimmermann, S. Miorelli, P R Massaguer, Gláucia Maria Falcão Aragão
    Abstract:

    The study of thermal resistant mould, including Byssochlamys nivea, is of extreme importance since it has been associated with fruit and fruit products. The aim of this work is to analyze the influence of water activity (aw) and ascospore age (I) on the growth of Byssochlamys nivea in Pineapple Juice. Mold growth was carried out under different conditions of water activity (aw) (0.99, 0.96, 0.95, 0.93, 0.90) and ascospore age (I) (30, 51, 60, 69, 90 days). Growth parameters as length of adaptation phase (�), maximum specific growth rate (µ max) and maximum diameter reached by the colony (A) were obtained through the fit of the Modified Gompertz model to experimental data (measuring radial colony diameter). Statistica 6.0 was used for statistical analyses (significance level � = 0.05). The results obtained clearly showed that water activity is statistically significant and that it influences all growth parameters, while ascospore age does not have any statistically significant influence on growth parameters. Also, these data showed that by increasing aw from

  • modeling the influence of water activity and ascospore age on the growth of neosartorya fischeri in Pineapple Juice
    Lwt - Food Science and Technology, 2011
    Co-Authors: M. Zimmermann, S. Miorelli, P R Massaguer, Gláucia Maria Falcão Aragão
    Abstract:

    Abstract The ascospores of resistant fungi, Neosartorya fischeri , can survive commercial pasteurization, diminishing the shelf life of these products. The time that the ascospores remain in the environment and the effect that they can cause on mold growth are still unknown. This study is aimed to evaluate the influence of water activity ( a w ) from 0.90 to 0.99 and the ascospore age ( I ) from 30 to 90 days of vitro incubation on the growth of N. fischeri in Pineapple Juice by mathematical modeling. The growth parameters on Pineapple Juice: adaptation phase ( λ ), maximum specific growth rate ( μ max ) and maximum diameter reached by the colony ( A ) were obtained by fitting Modified Gompertz and Logistic models to the experimental data. Both models were able to describe microbial growth in Pineapple Juice, but the Modified Gompertz model presented a slightly superior performance based on statistical indices (correlation coefficients ( R 2 ), mean square error (MSE), Bias Factor and Accuracy Factor). The minimum values of λ and A , calculated by the Modified Gompertz model, were 64.7 h and 6.3 mm, while the maximum values were 178.2 h and 20.8 mm, respectively. The result showed that ascospore age did not influence the growth but a w was statistically significant to the growth parameters λ and A .