Detection threshold of chocolate graininess: machine vs human
ISSN: 0007-070X
Article publication date: 19 May 2020
Issue publication date: 27 July 2020
Abstract
Purpose
Literature indicates that those solid chocolate particles cannot be detected by human beings that are smaller than a critical value between 25 and 35 µm. Chocolate containing particles larger than this range is thought to be perceived as grainy. However, there does not seem to be any publication which justifies this threshold. Hence, the main aim of this work is to determine if the threshold at which particles can be detected is indeed 30 µm.
Design/methodology/approach
Three dark chocolates containing solid particles of expected Dv,90 of 30 µm, 40 µm and 50 µm were produced. Particle Size Distribution (PSD) was determined using static light scattering while hardness and melting behaviour were characterised using a penetration test and Differential Scanning Calorimetry (DSC), respectively. Sensory analyses were performed with a trained panel (n = 9).
Findings
PSD analyses indicated that the solid particle Dv,90 of the three chocolates were around 30 µm, 40 µm and 60 µm, respectively. DSC measurements showed no significant difference in melting behaviour between the chocolates. Hardness measurements showed that the “30 µm chocolate” was significantly harder than both the “40 µm chocolate” and the “60 µm chocolate”, while trained panellists found that the graininess of the 60 µm chocolate was significantly higher than that of the 40 µm and 30 µm chocolates.
Practical implications
These results suggest that particle size detection threshold is higher than 40 µm. Chocolate manufacturers could thus increase the size of the biggest particles from 30 µm to 40 µm, leading to a decrease in production cost.
Originality/value
This is the first study to examine the particle detection limit of chocolate.
Keywords
Acknowledgements
We wish to thank Claudia Delbaere and Griet Spaepen for their help at the Cacaolab, Benny Lewille for his help with Mastersizer measurements and Kim Moens for her help with DSC and texture measurements. We also thank Nathalie De Clercq for her advice. We wish to thank Paul Van der Meeren and Quenten Denon for having allowed us to use the Mastersizer. Finally, we thank the EU for the financial support provided through the Internship - Erasmus program.Sara De Pelsmaeker and Juliette S. Behra are shared first co‐authors. Juliette S. Behra, “Laboratoire Charles Coulomb, Montpellier, France” is her current address.
Citation
De Pelsmaeker, S., Behra, J.S., Gellynck, X. and Schouteten, J.J. (2020), "Detection threshold of chocolate graininess: machine vs human", British Food Journal, Vol. 122 No. 9, pp. 2757-2767. https://doi.org/10.1108/BFJ-07-2019-0501
Publisher
:Emerald Publishing Limited
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