Volume: 2, 2023
2nd International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: T030
DOI: https://doi.org/10.24326/ICDSUPL2.T030
Published online: 19 April 2023
ICDSUPL, 2, T030 (2023)
Particle size distribution of dried and ground pear pomace
Anna Krajewska1*, Dariusz Dziki1, Renata Różyło2
1 Department of Thermal Technology and Food Process Engineering, Faculty of Production Engineering, University of Life Sciences in Lublin; 31 Głęboka St, 20-612, Lublin, Poland
2 Department of Food Engineering and Machines, Faculty of Production Engineering, University of Life Sciences in Lublin; 28 Głęboka St, 20-612 Lublin, Poland
* Corresponding author: anna.krajewska@up.lublin.pl
Abstract
The objective of this investigation was to determine the particle size distribution (PSD) of dried and ground pear pomace and assess the impact of drying method and temperature on PSD. Fresh pears were first pressed and then pomace was dried using contact drying at 40 °C (with microwave assistance of 50 W), 60°C and 80°C, as well as by freeze-drying at plate temperatures of 20°C, 40°C, and 60°C. The obtained dried pomace was subsequently ground using a knife mill. The PSD of powder was measured using laser diffraction method with a Malvern Masterisizer 3000, and PSD parameters such as d10, d50, d90 (the 10th, 50th, (median diameter), and 90th percentile of the total volume, respectively) and span, which represents the width of particle size distribution, were determined. The results showed that both drying method and temperature significantly influenced the PSD of the pear pomace. Freeze-drying led to greater particle size reduction. Higher drying temperature also resulted in increased the degree of finesses. The freeze-dried samples at a plate temperature of 60°C produced the highest amount of fine particles, while the lowest was obtained with contact drying at 40°C with microwave assistance (d10 values: 39 μm and 69 μm, respectively). Additionally, the value of d10 significantly differed between individual samples, except for pomace dried by contact method at 80°C and freeze-dried at 20°C. The highest median size of particles was recorded for pomace dried by contact method with microwave assistance at 40°C, while the lowest was observed for freeze-dried sample at 60°C (d50 values: 251 μm and 140 μm, respectively). The median values for contact-dried samples did not showed notable differences from each other. Freeze-drying at 20°C resulted in significantly higher size of particles compared to drying by contact method at plate temperatures of 40°C and 60°C. The highest amount of coarse particles was observed for pomace dried by contact method at 80°C, while the lowest was observed for freeze-dried samples at 60°C (d90 values: 559 μm and 320 μm, respectively). In conclusion, this study demonstrated that both drying method and temperature significantly influence the particle size distribution of dried and ground pear pomace.
How to cite
A. Krajewska, D. Dziki, R. Różyło, 2023. Particle size distribution of dried and ground pear pomace. In: 2nd International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL2.T030