Mustafa Ozilgen - Academia.edu (original) (raw)

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Papers by Mustafa Ozilgen

Research paper thumbnail of Energy Conversion Systems

Research paper thumbnail of Estimation of Thermodynamic Properties

Research paper thumbnail of Thermodynamic Assessment of the Industrial Bioprocesses

Research paper thumbnail of Kinetics of amino acid production by over-producer mutant microorganisms

Enzyme and microbial technology, Feb 1, 1988

Research paper thumbnail of Statistical process analysis in broiler feed formulation

Journal of the Science of Food and Agriculture, Sep 1, 1994

Statistical analysis of broiler feed production was done with data obtained in an industrial plan... more Statistical analysis of broiler feed production was done with data obtained in an industrial plant in an attempt to characterise the causes of variations in feed composition. Analysis of the experimental data has shown that the feed conversion ratio (FCR) for broilers was between 1.8 and 2.5. This large range of observations were thought to be caused by the wide range of variations in the composition of the feeds. The major factor contributing to the variance of the feed compositions was the variance of the raw materials. It was found that the proteins and moisture were distributed normally in most raw materials and feeds. Water molecules can diffuse in the raw materials and the feeds to make the whole batch uniform. On the other hand, the protein containing fractions tend to segregate due to density differences. Therefore, the moisture content of the raw materials tend to vary in a smaller range than those of the proteins. Mixing the feeds for three minutes or longer was sufficient to achieve suitable homogeneity, but controlling the range of the individual raw materials is recommended for further improvement of the process capability indices.

Research paper thumbnail of Salt, EDTA, and pH effects on rheological behavior of mold suspensions

Enzyme and microbial technology, Nov 1, 1992

Abstract The effects of surface properties on the rheological behavior of Aspergillus niger suspe... more Abstract The effects of surface properties on the rheological behavior of Aspergillus niger suspensions were studied at pH 2–7, with the addition of 0–0.10 m NaH 2 PO 4 , NaCl, CaCl 2 , AlCl 3 , and EDTA at shear rates of 0–21.6 s −1 . The structural network concept was used to discuss the consequences of cell-cell interactions on the rheological behavior. Analysis of the data indicated that the suspensions containing CaCl 2 nearly always had the smallest shear stress at all the pH values, indicating that, unlike with the yeast suspensions, Ca 2+ does not contribute to the specific bonding of the mold cells. At low pH and salt concentrations, NaH 2 PO 4 was better than AlCl 3 for promoting bond formation between the cells. When either the salt concentration or the pH was increased, AlCl 3 became a better bond formation agent than NaH 2 PO 4 . EDTA removes the charged groups from surfaces and encourages cell-cell contact via hydrophobic interactions. The shear stress and consistency index increased while the flow behavior index decreased with EDTA concentration.

Research paper thumbnail of Quality Control Charts for Storage of Eggs

Journal of Food Quality, Dec 1, 1994

Research paper thumbnail of Kinetics of wine spoilage by acetic acid bacteria

Journal of Chemical Technology & Biotechnology, Apr 24, 2007

Acid production in wines inoculated with acetic acid bacteria from vinegar was studied at 15°C, 2... more Acid production in wines inoculated with acetic acid bacteria from vinegar was studied at 15°C, 20°C, 25°C and 30°C and simulated with kinetic models. Results indicated that major wine spoilage did not occur during the growth of the microorganisms, but during their extended presence at high concentrations during the stationary and death phases. Acetophilic species were observed to resist death, which is in agreement with the mechanism suggested by Kittelmann et al.9 for the development of gradual acid tolerance by acetic acid bacteria.

Research paper thumbnail of NMR IMAGING, CALORIMETRIC, and MATHEMATICAL MODELING STUDIES of FOOD FREEZING

Journal of Food Process Engineering, Nov 1, 1996

Nuclear magnetic resonance imaging (MRI), calorimetry, and temperature measurements were used to ... more Nuclear magnetic resonance imaging (MRI), calorimetry, and temperature measurements were used to monitor cylindrical potato sections frozen at ‐11C and ‐42C. MRI showed the advance of the nonsymmetric freezing zone and loss of signal intensity as liquid water turned to ice. Differential calorimetry was used to follow heat removal during transient freezing. Measured times to 95% enthalpy change were 24 min (‐42C) and 49 min (‐11C), as compared to modeled values of 29 min (‐42C) and 100 min (‐11C). Times to 95% change in the NMR signal, integrated over the area of the image, were 21 min (‐42C) and 56 min (‐11C). Changes in NMR signal intensity could be correlated with the amount of unfrozen water remaining after a steady‐state had been reached. At ‐42C, NMR indicated 25% unfrozen water remaining as compared to 26% by calorimetry, and 22% by modeling. At ‐11C, NMR measured 67% unfrozen water remaining as compared to 48% by calorimetry, and 25% by equilibrium modeling.

Research paper thumbnail of MATHEMATICAL MODELING of TRANSIENT HEAT and MASS TRANSPORT IN A BAKING BISCUIT

Journal of Food Processing and Preservation, Jun 1, 1994

Research paper thumbnail of Energy utilization, carbon dioxide emission, and exergy loss in flavored yogurt production process

Research paper thumbnail of How to benefit from the food waste in the era of global warming

International Journal of Global Warming, 2020

Research paper thumbnail of Solubilization and rheological behaviour of raisin suspensions

Process Biochemistry, 1994

Research paper thumbnail of Assesment of the use of zero-emission vehicles and microbial fertilizers in beverage production

Journal of Cleaner Production, Nov 1, 2017

Research paper thumbnail of Nutrition and production related energies and exergies of foods

Renewable & Sustainable Energy Reviews, Nov 1, 2018

Research paper thumbnail of Renewable energy utilization in apple production process: A thermodynamic approach

Sustainable Energy Technologies and Assessments, Feb 1, 2021

Research paper thumbnail of NMR analysis and modelling of shrinkage and whey expulsion in rennet curd

Process Biochemistry, 1994

ABSTRACT The displacement of the curd surface after cutting and the profiles of residual water en... more ABSTRACT The displacement of the curd surface after cutting and the profiles of residual water entrapped inside were monitored using one dimensional magnetic resonance imaging (MRI). Shrinkage of the curd occurred in two phases: the curd shrank immediately during cutting and then continued shrinking at a lower velocity. Experimental data of the one dimensional shrinkage of the curd obtained from the literature were simulated with a logistic equation. NMR analysis and literature data showed that the shrinkage velocity was almost constant during the initial stages. The movement of the casein strands supplies the pump work to expel whey from the curd. By applying the fundamental principles of thermodynamics and fluid flow, a simple mathematical model was used to describe simultaneous shrinkage and whey expulsion. Profiles of residual water entrapped in the curd were simulated with this model to confirm its validity.

Research paper thumbnail of Parameters for predicting canning quality of dry kidney beans

Journal of the Science of Food and Agriculture, 1992

Mechanical damage to dry kidney beans was assessed using hot and cold water soak‐tests at 20 and ... more Mechanical damage to dry kidney beans was assessed using hot and cold water soak‐tests at 20 and 80°C, respectively. Damage was revealed as the middle lamella dissolved and the seed coats were released with zero order kinetics. Damage exposed in soak‐tests had no cause‐and‐effect relationship to damage found in the cans after thermal processing. However, significant correlations were found between both kidney bean density and seed coat weight, and the proportion of damaged beans in the can after processing (P <0.01). The proportion of damaged beans found in the can after thermal processing increased significantly when the ratio of the seed coat weight to bean volume ratio was < 10 g ml−1. These two simple measurable parameters offer potential for predicting canning quality of kidney beans.

Research paper thumbnail of Frequency factor-activation energy compensation relations for viscosity of the fruit juices

Journal of Food Engineering, 1992

Research paper thumbnail of Attachment and growth kinetics of anchorage-dependent BHK cells on microcarriers

Enzyme and microbial technology, Dec 1, 1989

Research paper thumbnail of Energy Conversion Systems

Research paper thumbnail of Estimation of Thermodynamic Properties

Research paper thumbnail of Thermodynamic Assessment of the Industrial Bioprocesses

Research paper thumbnail of Kinetics of amino acid production by over-producer mutant microorganisms

Enzyme and microbial technology, Feb 1, 1988

Research paper thumbnail of Statistical process analysis in broiler feed formulation

Journal of the Science of Food and Agriculture, Sep 1, 1994

Statistical analysis of broiler feed production was done with data obtained in an industrial plan... more Statistical analysis of broiler feed production was done with data obtained in an industrial plant in an attempt to characterise the causes of variations in feed composition. Analysis of the experimental data has shown that the feed conversion ratio (FCR) for broilers was between 1.8 and 2.5. This large range of observations were thought to be caused by the wide range of variations in the composition of the feeds. The major factor contributing to the variance of the feed compositions was the variance of the raw materials. It was found that the proteins and moisture were distributed normally in most raw materials and feeds. Water molecules can diffuse in the raw materials and the feeds to make the whole batch uniform. On the other hand, the protein containing fractions tend to segregate due to density differences. Therefore, the moisture content of the raw materials tend to vary in a smaller range than those of the proteins. Mixing the feeds for three minutes or longer was sufficient to achieve suitable homogeneity, but controlling the range of the individual raw materials is recommended for further improvement of the process capability indices.

Research paper thumbnail of Salt, EDTA, and pH effects on rheological behavior of mold suspensions

Enzyme and microbial technology, Nov 1, 1992

Abstract The effects of surface properties on the rheological behavior of Aspergillus niger suspe... more Abstract The effects of surface properties on the rheological behavior of Aspergillus niger suspensions were studied at pH 2–7, with the addition of 0–0.10 m NaH 2 PO 4 , NaCl, CaCl 2 , AlCl 3 , and EDTA at shear rates of 0–21.6 s −1 . The structural network concept was used to discuss the consequences of cell-cell interactions on the rheological behavior. Analysis of the data indicated that the suspensions containing CaCl 2 nearly always had the smallest shear stress at all the pH values, indicating that, unlike with the yeast suspensions, Ca 2+ does not contribute to the specific bonding of the mold cells. At low pH and salt concentrations, NaH 2 PO 4 was better than AlCl 3 for promoting bond formation between the cells. When either the salt concentration or the pH was increased, AlCl 3 became a better bond formation agent than NaH 2 PO 4 . EDTA removes the charged groups from surfaces and encourages cell-cell contact via hydrophobic interactions. The shear stress and consistency index increased while the flow behavior index decreased with EDTA concentration.

Research paper thumbnail of Quality Control Charts for Storage of Eggs

Journal of Food Quality, Dec 1, 1994

Research paper thumbnail of Kinetics of wine spoilage by acetic acid bacteria

Journal of Chemical Technology & Biotechnology, Apr 24, 2007

Acid production in wines inoculated with acetic acid bacteria from vinegar was studied at 15°C, 2... more Acid production in wines inoculated with acetic acid bacteria from vinegar was studied at 15°C, 20°C, 25°C and 30°C and simulated with kinetic models. Results indicated that major wine spoilage did not occur during the growth of the microorganisms, but during their extended presence at high concentrations during the stationary and death phases. Acetophilic species were observed to resist death, which is in agreement with the mechanism suggested by Kittelmann et al.9 for the development of gradual acid tolerance by acetic acid bacteria.

Research paper thumbnail of NMR IMAGING, CALORIMETRIC, and MATHEMATICAL MODELING STUDIES of FOOD FREEZING

Journal of Food Process Engineering, Nov 1, 1996

Nuclear magnetic resonance imaging (MRI), calorimetry, and temperature measurements were used to ... more Nuclear magnetic resonance imaging (MRI), calorimetry, and temperature measurements were used to monitor cylindrical potato sections frozen at ‐11C and ‐42C. MRI showed the advance of the nonsymmetric freezing zone and loss of signal intensity as liquid water turned to ice. Differential calorimetry was used to follow heat removal during transient freezing. Measured times to 95% enthalpy change were 24 min (‐42C) and 49 min (‐11C), as compared to modeled values of 29 min (‐42C) and 100 min (‐11C). Times to 95% change in the NMR signal, integrated over the area of the image, were 21 min (‐42C) and 56 min (‐11C). Changes in NMR signal intensity could be correlated with the amount of unfrozen water remaining after a steady‐state had been reached. At ‐42C, NMR indicated 25% unfrozen water remaining as compared to 26% by calorimetry, and 22% by modeling. At ‐11C, NMR measured 67% unfrozen water remaining as compared to 48% by calorimetry, and 25% by equilibrium modeling.

Research paper thumbnail of MATHEMATICAL MODELING of TRANSIENT HEAT and MASS TRANSPORT IN A BAKING BISCUIT

Journal of Food Processing and Preservation, Jun 1, 1994

Research paper thumbnail of Energy utilization, carbon dioxide emission, and exergy loss in flavored yogurt production process

Research paper thumbnail of How to benefit from the food waste in the era of global warming

International Journal of Global Warming, 2020

Research paper thumbnail of Solubilization and rheological behaviour of raisin suspensions

Process Biochemistry, 1994

Research paper thumbnail of Assesment of the use of zero-emission vehicles and microbial fertilizers in beverage production

Journal of Cleaner Production, Nov 1, 2017

Research paper thumbnail of Nutrition and production related energies and exergies of foods

Renewable & Sustainable Energy Reviews, Nov 1, 2018

Research paper thumbnail of Renewable energy utilization in apple production process: A thermodynamic approach

Sustainable Energy Technologies and Assessments, Feb 1, 2021

Research paper thumbnail of NMR analysis and modelling of shrinkage and whey expulsion in rennet curd

Process Biochemistry, 1994

ABSTRACT The displacement of the curd surface after cutting and the profiles of residual water en... more ABSTRACT The displacement of the curd surface after cutting and the profiles of residual water entrapped inside were monitored using one dimensional magnetic resonance imaging (MRI). Shrinkage of the curd occurred in two phases: the curd shrank immediately during cutting and then continued shrinking at a lower velocity. Experimental data of the one dimensional shrinkage of the curd obtained from the literature were simulated with a logistic equation. NMR analysis and literature data showed that the shrinkage velocity was almost constant during the initial stages. The movement of the casein strands supplies the pump work to expel whey from the curd. By applying the fundamental principles of thermodynamics and fluid flow, a simple mathematical model was used to describe simultaneous shrinkage and whey expulsion. Profiles of residual water entrapped in the curd were simulated with this model to confirm its validity.

Research paper thumbnail of Parameters for predicting canning quality of dry kidney beans

Journal of the Science of Food and Agriculture, 1992

Mechanical damage to dry kidney beans was assessed using hot and cold water soak‐tests at 20 and ... more Mechanical damage to dry kidney beans was assessed using hot and cold water soak‐tests at 20 and 80°C, respectively. Damage was revealed as the middle lamella dissolved and the seed coats were released with zero order kinetics. Damage exposed in soak‐tests had no cause‐and‐effect relationship to damage found in the cans after thermal processing. However, significant correlations were found between both kidney bean density and seed coat weight, and the proportion of damaged beans in the can after processing (P <0.01). The proportion of damaged beans found in the can after thermal processing increased significantly when the ratio of the seed coat weight to bean volume ratio was < 10 g ml−1. These two simple measurable parameters offer potential for predicting canning quality of kidney beans.

Research paper thumbnail of Frequency factor-activation energy compensation relations for viscosity of the fruit juices

Journal of Food Engineering, 1992

Research paper thumbnail of Attachment and growth kinetics of anchorage-dependent BHK cells on microcarriers

Enzyme and microbial technology, Dec 1, 1989