Loughborough University
Leicestershire, UK
LE11 3TU
+44 (0)1509 263171
Loughborough University

Loughborough University Institutional Repository

Please use this identifier to cite or link to this item: https://dspace.lboro.ac.uk/2134/21630

Title: Image analysis of palm oil crystallisation as observed by hot stage microscopy
Authors: Harrison, Peter D.
Smith, Kevin W.
Bhaggan, Krishnadath
Stapley, A.G.F.
Keywords: Crystal morphology
Growth models
Optical microscopy
Growth from melt
Issue Date: 2016
Publisher: © Elsevier
Citation: HARRISON, P. ... et al., 2016. Image analysis of palm oil crystallisation as observed by hot stage microscopy. Journal of Crystal Growth, 444, pp. 28-38.
Abstract: An image processing algorithm previously used to analyse the crystallisation of a pure fat (tripalmitin) has been applied to the crystallisation of a multicomponent natural fat (palm oil). In contrast to tripalmitin, which produced circular crystals with a constant growth rate, palm oil produced speckled crystals caused by the inclusion of entrapped liquid, and growth rates gradually decreased with time. This can be explained by the depletion of crystallisable material in the liquid phase, whereas direct impingement of crystals (the basis of the Avrami equation) was less common. A theoretical analysis combining this depletion with assuming that the growth rate is proportional to the supersaturation of a crystallisable pseudo-component predicted a tanh function variation of radius with time. This was generally able to provide good fits to the growth curves. It was found that growth rate was a relatively mild function of temperature but also varied from crystal to crystal and even between different sides of the same crystal, which may be due to variations in composition within the liquid phase. Nucleation rates were confirmed to vary approximately exponentially with decreasing temperature, resulting in much greater numbers of crystals and a smaller final average crystal size at lower temperatures.
Description: This paper was accepted for publication in the journal Journal of Crystal Growth and the definitive published version is available at http://dx.doi.org/10.1016/j.jcrysgro.2016.03.026.
Version: Accepted for publication
DOI: 10.1016/j.jcrysgro.2016.03.026
URI: https://dspace.lboro.ac.uk/2134/21630
Publisher Link: http://dx.doi.org/10.1016/j.jcrysgro.2016.03.026
ISSN: 0022-0248
Appears in Collections:Published Articles (Chemical Engineering)

Files associated with this item:

File Description SizeFormat
Harrison et al (2016) Image Analysis of Palm Oil - Journal of Crystal Growth.pdfAccepted version2.13 MBAdobe PDFView/Open


SFX Query

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.