Towards a better understanding of bio-processing: drying/extraction and state/phase transitions

食品工程研究依赖于对已知工艺和食品生物材料如何相互作用的研究，为该领域提供了新的特异性。在本提案中，干燥和提取这两个宏观过程在工业上被广泛应用于食品转化，将在微观水平上研究发生的相/状态转变的基础上，研究与之相关的现象。本项目的具体研究目标，以及研究成果的独特科学和工业意义如下：****1)收缩和淀粉转变：加深对淀粉和淀粉-水相互作用在空气干燥过程中食品收缩中的作用的理解。****了解淀粉类食品干燥过程中的收缩与状态/相变之间的关系，将有助于优化干燥策略，以提高干燥食品的最终质量。****2)通过数学建模进行风干和玻璃化转变：建立一个非菲克本构模型方程来表示高水分食品发生玻璃化转变时干燥过程中的传质行为。****通过开发一个准确而简单的本构方程，包括干燥过程中玻璃化在水分传递中的作用，我们将朝着高水分食品（或其他领域）应用的干燥过程的更精确的工业设计前进。****3)低温提取结晶：分析液氮浸提蜡过程中结晶和晶体生长对收率提高和提取选择性的影响。****通过将成分和晶体结构与晶体生长动力学联系起来，将阐明液氮浸泡从植物表面分离蜡质的可能机制，从而提高蜡收率和定制提取物的选择性，这可能会启发这种新型提取方法的特定应用。****上述目标通过过程工程，食品化学，植物学和材料科学研究领域之间的十字路口网络连接起来。通过招聘和培养多学科领域的高素质人才来培养研究人才，将实现这一科学计划的目标

Food engineering research relays on the study of how already known processes and food biomaterials interact with each other, giving novel specificity to the field. In this proposal, phenomena related to drying and extraction, two macroscale processes thoroughly applied to transform foods in industry, will be investigated on the basis of the study of phase/state transitions occurring at the microscale level. Specific research objectives to be developed in this program, together with distinctive scientific and industrial implication from the research outcome, follow:****1) Shrinkage and starch transitions: to deepen the understanding of the role of starch and starch-water interactions in food shrinkage during air-drying.****Understanding the relationship between shrinkage during drying of starchy foods and state/phase transitions will lead to optimal drying strategies for improvement of the final quality of dried foodstuffs.****2) Air-drying and glass transition through mathematical modelling: to develop a non-Fickian constitutive model equation for representing the mass transfer behavior during drying while glass transition occurs in high moisture food products.****By developing an accurate yet simple constitutive equation including the role of vitrification in moisture transfer during drying, we will move towards a more precise industrial design of the drying process for high moisture foods (or other field) applications.****3) Cryogenic extraction and crystallization: to analyze the impact of crystallization and crystal growth in yield enhancement and extract selectivity during wax extraction using liquid nitrogen immersion.****By relating composition and crystalline structure to crystal growth kinetics, possible mechanisms underlying the separation of waxes from plant surfaces by liquid nitrogen immersion will be elucidated, allowing increase in wax yield and tailor-made selectivity of extracts, which could enlight possible specific applications of this novel extraction method.****The above-mentioned objectives are connected by a network of crossroads between process engineering, food chemistry, botany and material sciences research fields. Training of research talents by recruitment and preparation of high-qualified personnel in multidisciplinary areas will round up the objectives of this scientific program.***