ICDSUPL4-F015

Volume: 4, 2025
4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT

Abstract number: F015

DOI: https://doi.org/10.24326/ICDSUPL4.F015

Published online: 9 April 2025

ICDSUPL, 4, F015 (2025)

Evaluation of process parameters for industrial onion dry peeling

Paweł Woźniak^1,2*, Tomasz Kiczek^1,2, Agata Bieńczak¹, Tomasz Michalak¹, Łukasz Ignasiak¹, Maksymilian Galiński¹

¹ Research Group of Mechanical Engineering, Łukasiewicz Research Network – Poznań Institute of Technology, Ewarysta Estkowskiego 6, 61-755 Poznań, Poland

² Faculty of Mechanical Engineering, Poznań University of Technology, Piotrowo 3, 60-965 Poznań, Poland

^{* Corresponding author: pawel.wozniak@pit.lukasiewicz.gov.pl}

Abstract

The demand for peeled onions is steadily increasing, with raw material often imported from European countries and processed in Poland. Currently, this process is still largely carried out manually, which is characterized by low efficiency and unfavorable working conditions due to the emission of volatile sulfur and acid compounds. Therefore, there is a need to automate processing to improve efficiency and working conditions. The aim of this study is to determine the process parameters affecting the effectiveness of onion dry skin removal and the amount of generated waste. The technology of onion cleaning is presented using the example of an industrial processing line developed at Łukasiewicz – PIT, which includes onion sorting, dry skin scoring, skin removal using an air stream, positioning, root and top removal, and manual cleaning at an inspection table. Operational tests were conducted using the Dormo onion variety, for which hardness changes were analyzed depending on the storage period. The tests were carried out under real production cycle conditions at Stanek Onions, a leading Polish producer of fully peeled onions. The results indicate that supply pressure and airflow rate have a crucial impact on process efficiency. Additionally, onion hardness decreases with storage time, and higher hardness enhances the cleaning effectiveness while reducing waste generation. Optimization of these process parameters resulted in over 90% cleaning efficiency and a reduction in waste, including dry skin, roots, and tops, to 10–15%. Furthermore, the evaluation of process parameters and onion properties, such as hardness, allows for further customization and optimization of the peeling process for different onion varieties. This flexibility ensures that the technology can be adapted to meet the requirements of various onion types, ensuring high-quality processing regardless of the characteristics of the raw material. In conclusion, the optimization of the high-performance mechanical dry skin removal method not only addresses the challenges associated with manual peeling but also ensures that high-quality onion processing can be achieved in a more efficient and sustainable manner. The proposed automated system has the potential to significantly improve the efficiency of onion processing, reduce waste, and provide a safer and more cost-effective solution for the industry.

Keywords: onion cleaning, dry skin, root and top, compressed air, process parameters

How to cite

P. Woźniak, T. Kiczek, A. Bieńczak, T. Michalak, Ł. Ignasiak, M. Galiński, 2025. Evaluation of process parameters for industrial onion dry peeling. In: 4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL4.F015