Partner: Rafał Kościesza


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.

Sound speed measurements were performed in an ultrasonic setup with a DAG oil sample located in the high-pressure chamber. An ultrasonic method that uses cross-correlation method to determine the time-of-flight of the ultrasonic pulses through the liquid was employed to measure the sound velocity in DAG oil. This method is fast and reliable tool for measuring sound velocity. The DAG oil density at high pressure was determined from the monitoring of sample volume change. The adiabatic compressibility and isothermal compressibility have been calculated on the basis of experimental data. Discontinuities in isotherms of the sound speed versus pressure point to the existence of phase transitions in DAG oil. The ultrasonic method presented in this study can be applied to investigate the physicochemical parameters of other liquids not only edible oils.

Keywords:

Ultrasonic methods, Sound velocity, Phase transitions, High pressure food processing, Physicochemical parameters

Affiliations:
Kiełczyński P.-IPPT PAN
Szalewski M.-IPPT PAN
Balcerzak A.-IPPT PAN
Wieja K.-IPPT PAN
Malanowski A.-other affiliation
Kościesza R.-other affiliation
Tarakowski R.-other affiliation
Rostocki A.J.-other affiliation
Siegoczyński R.M.-other affiliation
2.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:
Malanowski A.-other affiliation
Rostocki A.J.-other affiliation
Kiełczyński P.-IPPT PAN
Szalewski M.-IPPT PAN
Balcerzak A.-IPPT PAN
Kościesza R.-other affiliation
Tarakowski R.-other affiliation
Ptasznik S.-Air Force Institute of Technology (PL)
Siegoczyński R.M.-other affiliation
3.Kos A., Tefelski D.B., Kościesza R., Rostocki A.J., Roszkiewicz A., Ejchart W., Jastrzębski C., Siegoczyński R.M., Certain physico-chemical properties of triolein and methyl alcohol–triolein mixture under pressure, HIGH PRESSURE RESEARCH, ISSN: 0895-7959, Vol.27, No.1, pp.39-42, 2007