Food Engineering Reviews

, Volume 9, Issue 1, pp 50–70

Mathematical Modeling and Use of Magnetic Resonance Imaging (MRI) for Oil Migration in Chocolate Confectionery Systems

Review Article

DOI: 10.1007/s12393-016-9152-4

Cite this article as:
Cikrikci, S. & Oztop, M.H. Food Eng Rev (2017) 9: 50. doi:10.1007/s12393-016-9152-4

Abstract

Oil migration is a common problem in chocolate confectionery products leading to quality defects, particularly fat bloom. Several factors such as contact area, ratio of the two fat phases, type of the fat, solid fat content, presence of non-fat solid particles, particle size, viscosity, structure, concentration gradient of triacylglycerols (TAGs), and storage temperature have all effect on migration rate. Mechanism of oil migration has still not been clearly understood, but possible mechanisms have been suggested and studied in the literature. Diffusion mechanism was demonstrated and modeled in many studies. Although there are so many methods to monitor and quantify migration, magnetic resonance imaging (MRI) is among the most promising techniques as being non-destructive. This review covers the literature related to basics of migration, mechanisms, and monitoring and modeling migration in chocolate through MRI and also includes a brief description about chocolate, chocolate processing, and fundamental concepts in MRI.

Keywords

Oil migration Magnetic resonance imaging (MRI) Mathematical modeling 

Abbreviations

A

Contact area (cm2)

C

Concentration (mol/cm3)

C0

Equilibrium concentration over time (mol/cm3)

CFP(t)

Hazelnut concentration in filter paper (kg/m3)

D

Diffusion coefficient or diffusivity (cm2 s−1)

Deff

Effective diffusion coefficient (cm2 s−1)

Dl

Diffusion coefficient in the liquid phase of the cocoa butter (m2/s)

g

Gravity

h

Height (cm)

h

Equilibrium height (cm)

J

Molar diffusion flux of the migrating molecules (mol cm−2 s−1)

k

Boltzmann constant (1.38 × 10−23 J K−1)

k

Kinetic rate constant

K

Partition distribution constant

l

Thickness (cm)

L

Distance

L(t)

Slab thickness expressed as a function of time

M

Observed pixel intensity in MRI

M0

Total pixel liquid proton intensity in MRI

ms

Amount of migrated oil at infinity

mt

Amount of migrated oil at time t

r

Molecular radius of the diffusing material (cm)

t

Time (s)

T

Absolute temperature (K)

T1

Longitudinal relaxation time (spin–lattice relaxation time)

T2

Transverse relaxation time (spin–spin relaxation time)

TE

Echo time

TR

Repetition time

V

Volume (cm3)

ε

Void volume

vv

Volume average velocity

x

Position

α

Aspect ratio

Ω

Angle between the capillary and a reference horizontal datum plane

β

Time constant

ρ

Density (g/cm3)

θ

Contact angle between the fluid and the capillary wall

γ

Surface tension of the fluid (units, N m−1)

μ

Viscosity

η

Viscosity of the medium (cp)

τ

Global tortuosity factor

Volume fraction in chocolate

LF

Volume fraction of liquid fat in chocolate

\( {\varnothing}_{NF}^{\mathrm{T}} \)

Volume fraction of non-fat solid in chocolate

\( {\varnothing}_{SF}^{\mathrm{Fat}} \)

Volume fraction of solid fat in the cocoa butter phase

Funding information

Funder NameGrant NumberFunding Note
Orta Doğu Teknik Üniversitesi
  • BAP-03-14-2016-002.

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of Food Engineering|Middle East Technical UniversityAnkaraTurkey

Personalised recommendations