Studies on the influence of novel triglyceride chemistry on fat crystallization

该项目的目标是更好地了解甘油三酯化学在高压和超声场存在下对食用脂肪成核和生长的影响。虽然食用油在常压下的相行为已经得到了较好的研究，但关于油脂在高压下的基本结晶成核和生长行为的研究却很少。它们的高压相行为对许多行业都很重要。例如，由于缺乏对生物燃料/柴油混合物的高压结晶行为的了解，在柴油发动机中使用高压共轨，以及将植物油衍生物以生物燃料的形式引入柴油中，给核心制造商带来了一些问题。食品工业中越来越多地使用高压加工，这给希望加工含脂肪食品的制造商带来了类似的问题。对结晶成核和生长的基础科学有很好的了解，这对于发展许多对人口、饮食和健康可能有很大影响的食品制造工艺至关重要。在常压和加压之间对这一主题的研究将普遍有助于改进涉及结晶的食品工艺的工程。众所周知，超声波对结晶和结晶成核有重要的影响，然而，所涉及的机制还不是很清楚，本项目将从理论和实验的角度来考察它们的影响。具体地说，将使用利兹大学现有的设备、SAXS/WAXS、DSC和超声波光谱仪，在高压下研究可可油等经过充分研究的食用油体系在存在和没有超声场的情况下的结晶情况。如果利兹的初步数据证明了这一点，那么钻石同步加速器和其他强X射线设施的光束时间也可能是合理的。这名学生将从利兹和雀巢的合作中获得现实世界的工业研究经验，这是扩大巧克力和糖果制造可用脂肪和植物油范围的更广泛努力的一部分，从而改善饮食和健康消费者。

The project objective is to gain a better understanding of the impact of triglyceride chemistry on edible fat nucleation and growth at high pressure and in the presence of an ultrasound field. Whilst the phase behaviour of edible oils has been relatively well studied at ambient pressures, there are only a handful of studies of the fundamental crystal nucleation and growth behaviour of oils and fats at high pressures. Their high pressure phase behaviour is important to a number of industries. For example the use of high pressure common rails in diesel engines, together with the introduction of vegetable oil derivatives into diesel fuel in the form of biofuels has created a number of problems for core manufacturers due to the lack of understanding of the high pressure crystallization behaviour of biofuel/diesel mixtures. The increasing use of high pressure processing in the food industry presents similar problems to manufacturers who wish to process fat containing foods. A good understanding of the fundamental science of crystal nucleation and growth is central to the development of many food manufacturing processes with potentially high impact on population diet and health. Studies of this subject between ambient and elevated pressure will contribute generally to improved engineering of food processes involving crystallization. It is well known also that ultrasound has significant impact upon crystallization and crystal nucleation, however, the mechanisms involved are not so well understood and this project will examine their impact from the theoretical and experimental point of view. Specifically, the crystallization of well-studied edible oil systems such as cocoa butter in the presence and absence of an ultrasound field will be studied at elevated pressures using equipment available at Leeds, SAXS/WAXS, DSC and Ultrasound Spectroscopy. If the preliminary data at Leeds justifies it, a case may also be made for beam time at the Diamond Synchrotron and other intense X-ray facilities. The student will gain real-world industrial research experience from the collaboration between Leeds and Nestle as part of a wider effort to enlarge the range of fats and vegetable oils available to chocolate and confectionery manufacture, hence improving diet and health consumers.