Dielectric Properties of Water in Butter and Water—AOT—Heptane Systems Measured Using Terahertz Time-Domain Spectroscopy

Abstract

We investigate the dielectric properties of water confined in nanometer-sized inverse micelles in mixtures of water, AOT, and heptane. We show that the dielectric properties of the confined water are dependent on the water pool size and different from those of bulk water. We also discuss the dielectric properties of different vegetable oils, lard, and butter, and use these properties to deduce the dielectric properties of water in butter, which are shown to deviate significantly from the dielectric properties of bulk water.

A Comprehensive Review on Food Applications of Terahertz Spectroscopy and Imaging

“…Sodium bis(2ethylhexyl)sulfosuccionate (AOT) is an ionic surfactant used to make water‐in‐oil microemulsions. THz‐TDS was used to study the dielectric properties of systems containing water in butter as well as water‐AOT,‐heptane (W‐AOT‐H) (Møller, Folkenberg, & Jepsen, ). An increase in the dielectric function of the real and imaginary part of the confined water pool was observed for the W‐AOT‐H system.…”

“…Møller et al. () investigated the dielectric properties of butter, lard, and vegetable oils. Each oil presented a unique THz spectrum for the imaginary and real parts of the dielectric function.…”

“…Møller et al. () showed the effect of the real and imaginary part of water pool on the THz spectra. The level of hydration also affects the low‐frequency vibrational modes of proteins.…”

Sensing self-assembled alkanethiols by differential transmission interrogation with terahertz metamaterials

“…The control experiment was also following the aforementioned procedures by immersing the SRRs in liquid ethanol for 11 h and then drying them with nitrogen gas. Our home-built THz time-domain spectroscopy [8,38] setup is based on the generation from a low-temperature-grown GaAs photoconductivity antenna integrated with a silicon hemisphere and the ZnTe crystal detection of the THz pulse radiation, which can be found in our previous work [8,39]. The measurements have been done on the system purged with dry nitrogen to avoid the strong influence of the water vapor in the ambient.…”

Studies on determination of mathematical relationships between rapeseed oil content and electrical properties of butter and fat mixes

“…A dielectric constant may also be a basis of a simple method for the determination of water content of butter. Reference works report also on attempts undertaken to compare the electrical properties of butter and other fats, including vegetable oils or lard (Parkash and Armstrong, 1969;Hu et al, 2008;Lizhi et al, 2008;Møller et al, 2010). The available literature lacks, however, reports on the feasibility of using electrical properties for the determination of the content of vegetable oil in fat mixes.…”