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  • 1 Szent Istvan University, 14-16 Somloi str., Budapest, Hungary
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In the case of organic production the quality assessment of the fruits and vegetables is especially important. Monitoring of the maturation and ripening process, early detection of diseases, decision about harvest date and postharvest treatment need reliable, objective and – preferably – non-destructive quality testing methods. Dynamic hardness or stiffness measurement methods (resonance, impact, wave propagation) offer very useful tools in this field, but with strong limitations in applicability area and/or physical interpretation of the measured parameters. Our objective was to develop method and appropriate portable instrumentation to measure surface hardness – as quality measure – with a nondestructive method.

The computer controlled instrument has an electromagnetically excited impactor fitted with a piezoelectric acceleration sensor, a signal conditioner and A/D converter. To ensure the uniform contact behavior (contact area) between the impactor and the tested produce of wide range of shape, spherical head was applied. Conclusively, Hertz contact theory is to be applied for evaluation of the impact signal. Instead of using empirical “hardness index” – as in the case of several existing instruments – our objective was the physical interpretation of the contact phenomena. The measured acceleration signal was mathematically processed to calculate real physical parameters (force, speed, deformation), and to characterize the process similarly to the widely used texture analyzers, penetrometers. A new hardness parameter – “dynamic elastic modulus” – was introduced. According to the methodological investigations, the measurement was found to be perfectly non-destructive for a wide range of products. Conclusively, the developed method offers a useful tool for quality evaluation of organic horticultural products.

  • Cheng-Chang Lien , Ching-Hua Ting (2014) Assessing guava maturity by statistical analyses of dropped fruit impact responses. Postharvest Biology and Technology, 95, 2027.

    • Search Google Scholar
    • Export Citation
  • De Belie, N. , S. Schotte, J. Lammertyn, B. Nicolai, J. De Baerdemaeker (2000) Firmness changes of pear fruit on the tree with the acoustic impulse response technique. AgEng, Warwick 2000, Paper Number 00–PH–001.

    • Search Google Scholar
    • Export Citation
  • Felföldi J , T. Ignát. (1999) Dynamic method for quick and non-destructive measurement of the surface firmness of fruits and vegetables. Hungarian Agricultural Engineering 12, 2930.

  • Felföldi, J. and A. Fekete (2003) Detection of small scale mechanical changes by acoustic measuring systemASAE Annual Meeting Paper, Las Vegas, No. 036097, pp. 18.

    • Search Google Scholar
    • Export Citation
  • Felföldi, J. and V. Muha (2007) In-vivo acoustic measurement of mechanical properties of fruits –International Conference on Agricultural, Food and Biological Engineering & Post Harvest/Production Technology, Khon Kaen – Paper No. 61, pp. 17.

    • Search Google Scholar
    • Export Citation
  • Garcı́a-Ramos, F.J., J Ortiz-Cañavate, M. Ruiz-Altisent, J. Dı́ez, L. Flores, I. Homer, J.M. Chávez (2003) Development and implementation of an on-line impact sensor for firmness sensing of fruits. Journal of Food Engineering, 58(1), 5357.

    • Search Google Scholar
    • Export Citation
  • Mizrach, A. (2000) Determination of avocado and mango fruit properties by ultrasonic technique. Ultrasonics, 38(1–8), 717722.

  • Mohsenin, N. N. (1986). Physical properties of plant and animal materials. Gordon and Breach Science Publishers, London.

  • Muha, V., J. Felföldi (2005) Methodological examinations of dynamic texture measurement. Journal of Food Physics XVII-XVIII, 312.

  • Padungsak Wanitchang, Anupun Terdwongworakul , Jaitip Wanitchang, Natrapee Nakawajana (2011) Non-destructive maturity classification of mango based on physical, mechanical and optical properties. Journal of Food Engineering, 105(3), 477484.

    • Search Google Scholar
    • Export Citation
  • Rodriguez-Sinovas, L., M. Ruiz-Altisent and J.L. de la Plaza Perez (1991) Bruise development and fruit response of pear (cv. Blanquilla) under impact conditions. Journal of Food Engineering, 14, 289301.

    • Search Google Scholar
    • Export Citation
  • Zsom-Muha, V. and J. Felfoldi (2007) Vibration Behavior of Long Shape VegetablesProgress in Agricultural Engineering Sciences, 3, 2146.

    • Search Google Scholar
    • Export Citation

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  • Mechanical Engineering SJR Quartile Score (2018): Q3
  • Industrial and Manufacturing Engineering SJR Quartile Score (2018): Q3
  • Scimago Journal Rank (2018): 0.202
  • SJR Hirsch-Index (2018): 5

Language: English

Founded in 2004
Publication: One volume annually
Publication Programme: 2020. Vol. 16. 

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Senior editors

Editor(s)-in-Chief: Felföldi, József

Chair of the Editorial Board Szendrő, Péter

Editorial Board

  • Beke, János;
  • Fenyvesi, László;
  • Szendrő, Péter;
  • Felföldi, József


Advisory Board

  • De Baerdemaeker, Josse
  • Dimény, I.
  • Funk David B.
  • Geyer, Martin
  • Janik, József
  • Kutzbach, Heinz D.
  • Mizrach, Amos
  • Neményi, Miklós
  • Schulze-Lammers, Peter
  • Sitkei, György
  • Sun, Da-Wen
  • Szendrő, Péter
  • Tóth, László

Prof. Felföldi, József
Institute: Physics-Control Department, Szent István University
Address: 1118 Budapest Somlói út 14-16
Phone: +36 1 305 7206