Experimental and numerical evaluation of the effect of micro-aeration on the thermal properties of chocolate
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Thermal properties, such as thermal conductivity, specific heat capacity and latent heat, influence the melting and solidification of chocolate. The accurate prediction of these properties for micro-aerated chocolate products with varying levels of porosity ranging from 0% to 15% is beneficial for understanding and control of heat transfer mechanisms during chocolate manufacturing and food oral processing. The former process is important for the final quality of chocolate and the latter is associated with sensorial attributes, such as grittiness, melting time and flavour. This study proposes a novel multiscale Finite Element Model to accurately predict the temporal and spatial evolution of temperature across chocolate samples. The model is evaluated via heat transfer experiments at temperatures varying from 16 °C to 45 °C. Both experimental and numerical results suggest that the rate of heat transfer within the micro-aerated chocolate is reduced by 7% when the 15% micro-aerated chocolate is compared to its solid counterpart. More specifically, on average, the thermal conductivity decreased by 20% and specific heat capacity increased by 10% for 15% micro-aeration, suggesting that micro-pores act as thermal barriers to heat flow. The latter trend is unexpected for porous materials and thus the presence of a third phase at the pore’s interface is proposed which might store thermal energy leading to a delayed release to the chocolate system. The developed multiscale numerical model provides a design tool to create pore structures in chocolate with optimum melting or solidifying response.
Date Issued
2022-05-07
Date Acceptance
2022-04-02
Citation
Food and Function, 2022, 13 (9), pp.4993-5010
ISSN
2042-6496
Publisher
Royal Society of Chemistry
Start Page
4993
End Page
5010
Journal / Book Title
Food and Function
Volume
13
Issue
9
Copyright Statement
© The Royal Society of Chemistry 2022. This article is licensed under aCreative Commons Attribution 3.0 Unported Licence (https://creativecommons.org/licenses/by/3.0/)
License URL
Sponsor
Nestec York Ltd
Identifier
https://pubs.rsc.org/en/content/articlelanding/2022/fo/d1fo04049a
Grant Number
3201023939
Subjects
Science & Technology
Life Sciences & Biomedicine
Biochemistry & Molecular Biology
Food Science & Technology
PARTICLE-SIZE DISTRIBUTION
CRYSTALLIZATION BEHAVIOR
SUSPENDED-SOLIDS
POROUS MATERIALS
DARK CHOCOLATE
CONDUCTIVITY
MILK
COMPOSITE
MICROSTRUCTURE
MODEL
Cacao
Chocolate
Hot Temperature
Temperature
Thermal Conductivity
0908 Food Sciences
Publication Status
Published
Date Publish Online
2022-04-04