Why Radio frequency heating is more effective to deactivate and release non-nutritive components from pulses

过去几年，加拿大豆类产业发展迅速，豆类出口销售增长迅速。射频加热节能，适合大规模商业应用，但已在有限的地区实施。本研究的目的是探索脉冲加工过程中显微组织变化的机理及其对产品质量的影响。该项目需要三个工作包。工作包1：脉冲的同步加速器三维X射线成像S校区的第四代同步加速器将用于研究在受控射频加热条件下孔隙、水分、蛋白质和淀粉的三维X射线图像。我们将研究可通过同步辐射获得相干X射线源的X射线成像同轴相衬断层成像的对比度增强。使用加拿大光源的生物医学成像和治疗设施，将详细研究微通道发育的3D图像，以及脉冲中毛孔、水、蛋白质和淀粉的密度和分布的变化。我们还将比较常规焙烧和高功率射频加热处理的脉冲的3D骨架孔隙空间。工作包2：优化粒子流的垂直喷头设计要有效地使用射频加热系统，关键是要有一个适当设计的喷头。为了确保颗粒连续(无缝隙)和均匀地流入两个电极之间的空间，我们将设计和建造垂直喷涂器。对于颗粒流，我们将考虑出口处有致动器的自由落体型和螺旋型。我们将测试平行和同轴电极配置。基于离散元方法的计算机模拟将对这两种类型使用不同的参数进行优化设计。优化的施加器将被制造出来，并测试在射频加热过程中的颗粒流动和温度分布。工作包3：射频加热过程中的脉冲质量比较使用从工作包2中选择的施加器，我们将观察在不同操作条件下非营养成分是如何从脉冲中失活和释放的。将进行平行测试，以比较射频加热和传统的热梯度驱动焙烧。在工艺条件优化后，将对两种加热方法的其他质量参数(颜色、质地、蛋白质和淀粉)进行比较。非营养成分的去除将与同步加速器X射线图像和脉冲内的温度梯度进行定量关联，用于射频加热和传统烘焙。显然，这三个领域的研究结果将产生重大的积极影响，并将为加拿大的一系列PULSE产品增值。该计划还将通过跨学科研究为HQP提供高质量的培训。

Canadian pulse industries are growing fast and export sales of pulses increased rapidly over past years. Radio frequency heating is energy efficient and suitable for large-scale commercial applications, but has been implemented in limited areas. The goal of my research is to discover the mechanism of the microstructure changes that occur during pulse processing and their effect on product quality. The project requires three work packages. Work package 1: Synchrotron 3D X-ray imaging of pulses The 4th generation synchrotron on the U of S campus will be used to study 3D X-ray images of pore, water, protein, and starch distributions under controlled RF heating conditions. We will study enhancement of the contrast in X-ray imaging in-line phase-contrast tomography with coherent X-ray sources accessible via synchrotron radiation. Using Biomedical Imaging and Therapy Facility at Canadian Light Source, 3D images of microchannel development, changes in the density and distribution of pore, water, protein, and starch in the pulses will be studied in detail. We will also compare the 3D skeletonized pore spaces of pulses treated with conventional roasting and high-power RF heating. Work package 2: Vertical applicator design for optimized particle flow To use an RF heating system efficiently, it is critical to have a properly designed applicator in place. To ensure a continuous (no gaps) and uniform flow of particles into the space between the two electrodes, we will design and build vertical applicators. For particle flow, we will consider a free-falling type with an actuator at the exit and an auger type. We will test parallel and co-axial electrode configurations. Computer simulations based on the discrete element method will be conducted for both types using different parameters for design optimization. The optimized applicators will be fabricated, and tested for particle flow and temperature distribution during RF heating. Work package 3: Pulse quality comparison During RF heating with the selected applicators from Work package 2, we will observe how non-nutritive components are deactivated and released from the pulses under various operating conditions. Parallel tests will be performed to compare RF heating with conventional thermal gradient-driven roasting. After optimization of the process conditions, additional quality parameters (colour, texture, protein, and starch) will be compared for the two heating methods. The non-nutritive components removal will be quantitatively correlated with synchrotron X-ray images and temperature gradients inside the pulses for both RF heating and conventional roasting. It is clear that the results of these three areas of research will have a significant positive impact and will add value to a wide array of pulse products in Canada. The program will also provide quality training for HQPs through interdisciplinary research.