Partner: Rafał Tarakowski |
Recent publications
1. | Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Malanowski A.♦, Kościesza R.♦, Tarakowski R.♦, Rostocki A.J.♦, Siegoczyński R.M.♦, Determination of physicochemical properties of diacylglycerol oil at high pressure by means of ultrasonic methods, Ultrasonics, ISSN: 0041-624X, DOI: 10.1016/j.ultras.2014.06.013, Vol.54, No.8, pp.2134-2140, 2014 Abstract: The purpose of the paper is to address, using ultrasonic methods, the impact of temperature and pressure on the physicochemical properties of liquids on the example of diacylglycerol (DAG) oil. The paper presents measurements of sound velocity, density and volume of DAG oil sample in the pressure range from atmospheric pressure up to 0.6 GPa and at temperatures ranging from 20 to 50°C. Ultrasonic methods, Sound velocity, Phase transitions, High pressure food processing, Physicochemical parameters Affiliations:
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2. | Rostocki A.J.♦, Tarakowski R.♦, Kiełczyński P., Szalewski M., Balcerzak A., Ptasznik S.♦, The Ultrasonic Investigation of Phase Transition in Olive Oil up to 0,7 GPa, JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY, ISSN: 0003-021X, DOI: 10.1007/s11746-013-2223-2, Vol.90, No.6, pp.813-818, 2013 Abstract: This paper presents measurements of sound velocity and attenuation in olive oil, with known chemical composition, as a function of pressure, within the range of pressure up to 0.7 GPa. Dependencies of sound velocity, relative ultrasonic wave attenuation, volume, and adiabatic compressibility on pressure show discontinuities. This proves the existence of the first order phase transition in olive oil (liquid to solid-like phase transition). Rapid and large changes in relative attenuation testify to the existence of a phase transition in olive oil. Moreover, the kinetics of phase transition was also investigated. Measurement of acoustic wave velocity and relative attenuation in olive oil during the phase transition and in the high-pressure phase is a novelty. The results obtained can be useful in the development of new methods in food (edible oils) control, processing, and preservation. Keywords:Vegetable oils, Sound velocity, Triacylglycerols, Phase transition, High pressure Affiliations:
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3. | Rostocki A.J.♦, Malanowski A.♦, Tarakowski R.♦, Szlachta K.♦, Kiełczyński P., Szalewski M., Balcerzak A., Ptasznik S.♦, The sound velocity measurement in diacylglycerol oil under high pressure, HIGH PRESSURE RESEARCH, ISSN: 0895-7959, DOI: 10.1080/08957959.2013.769975, Vol.33, No.1, pp.172-177, 2013 Abstract: In this article, the influence of high pressure on sound velocity at 293 K has been presented. The investigated diacylglycerol oil (DAG – [D82T18]AG) was composed of 82% DAGs and 18% triacylglycerols. The variation of sound velocity with hydrostatic pressure for DAG was evaluated up to 400 MPa. The phase transformation in DAG has been observed as a discontinuity of the dependence of sound velocity on pressure. The sound velocity during the phase transition has shown distinct increment. Also the volume changes have been measured. It has shown the rapid drop of the volume at the phase transformation pressure due to the possible crystallization of DAG oil. Keywords:high pressure, velocity, DAG Affiliations:
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4. | Malanowski A.♦, Rostocki A.J.♦, Kiełczyński P., Szalewski M., Balcerzak A., Kościesza R.♦, Tarakowski R.♦, Ptasznik S.♦, Siegoczyński R.M.♦, Viscosity and compressibility of diacylglycerol under high pressure, HIGH PRESSURE RESEARCH, ISSN: 0895-7959, DOI: 10.1080/08957959.2013.775649, Vol.33, No.1, pp.178-183, 2013 Abstract: The influence of high pressure on viscosity and compressibility of diacylglycerol (DAG) oil has been presented in this paper. The investigated DAG oil was composed of 82% of DAGs and 18% TAGs (triacylglycerols). The dynamic viscosity of DAG was investigated as a function of the pressure up to 400 MPa. The viscosity was measured by means of the surface acoustic wave method, where the acoustic waveguides were used as sensing elements. As the pressure was rising, the larger ultrasonic wave attenuation was observed, whereas amplitude decreased with the liquid viscosity augmentation. Measured changes of physical properties were most significant in the pressure range near the phase transition. Deeper understanding of DAG viscosity and compressibility changes versus pressure could shed more light on thermodynamic properties of edible oils. Keywords:DAG viscosity, compressibility, phase transitions, transmitted and scattered light Affiliations:
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