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对食用脂肪在高压和超声场存在下成核和生长的影响。虽然食用油在环境压力下的相行为已经得到了相对较好的研究，但对油脂在高压下的基本结晶成核和生长行为的研究却很少。它们的高压相特性对许多工业都很重要。例如，在柴油发动机中使用高压共轨，再加上在柴油燃料中以生物燃料的形式引入植物油衍生物，由于缺乏对生物燃料/柴油混合物的高压结晶行为的理解，给核心制造商带来了许多问题。在食品工业中越来越多地使用高压加工，给希望加工含脂肪食品的制造商带来了类似的问题。对晶体成核和生长的基础科学的良好理解对于许多食品制造工艺的发展至关重要，这些工艺可能对人口的饮食和健康产生重大影响。对环境压力和高压之间的这一问题的研究将有助于改进涉及结晶的食品加工工程。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研究它们的影响。具体来说，将使用利兹、SAXS/WAXS、DSC和超声波光谱学的设备，在高压下研究经过充分研究的食用油系统（如可可脂）在超声场存在和不存在的情况下的结晶。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射线设备的光束时间也可能是一个例子。学生将从利兹和雀巢之间的合作中获得实际的工业研究经验，作为扩大巧克力和糖果制造中可用的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.