Abstract:
Oleogels were thermally reversible plastic fats with low content of saturated and trans fatty acids and had the application prospect of replacing traditional plastic fats. The soybean oleogels were prepared using the mixture of monopalmitate (MP) and carnauba wax (CW) as gelator with the amount of 10% (based on the mass of the oleogel). The effects of the ratios of MP to CW on the thermal properties and crystallization kinetics of the oleogels were investigated. The thermal properties and crystallization kinetics of the oleogels were determined by differential scanning calorimetry (DSC) and pulsed nuclear magnetic resonance (p-NMR) spectroscopy, respectively. The data of DSC showed that the peak temperatures (
Tps) and enthaplies of the oleogels in melting and crystallization process were affected by the ratio of MP to CW, the
Tps of the oleogels in the 1
st melting process were higher than those of the corresponding peaks in the 2
nd melting process, the
Tps of the oleogels in the melting process were higher than those of the corresponding peaks in the crystallization process. In the melting and crystallization process, with the CW content increasing, the
Tps with lower temperature decreased first and then increased, the
Tps with higher temperature increased, the melting and crystallization enthaplies of the oleogels declined first and then increased. The crystallization kinetics of the oleogels was fitted using Gompertz model. The maximum solid fat content when crystallization time approached infinity (
SFCmax), crystallization rate (
μ) and induction time (
λ) was affected greatly by the ratio of MP to CW. With CW content in the gelators increasing,
SFCmax and
μ decreased first and then increased,
λ increased first and decreased.