IRES Track I: The Broad Impact of Flavor. A Research Experience on Metabolomics of Microbial Populations during Cacao Fermentation at the Escuela Superior Politecnica de Litoral

IRES以开发发酵过程中的复杂风味可可为中心，旨在提高学生参与者的全球和科学能力。该计划促进少数族裔和代表不足的学生参与STEM学科。在过去的十年里，工艺巧克力行业在美国和世界其他地区发展迅速。发酵可可豆和干可可豆的全球贸易影响着数百万人的生活，从可可种植者到巧克力制造商和消费者。世界上约5%的可可来自生产高品质巧克力的品种，厄瓜多尔是此类品种的最大生产国之一。然而，发酵豆的质量变化很大，影响了巧克力的质量、可接受性和价值。发酵可可的质量差异也降低了当地可可种植者的价格，这些种植者大多是小农户。尽管它会影响巧克力的味道，但在巧克力生产的所有阶段中，可可发酵仍然是最复杂的，也是研究最少的。在这个IRES项目中，美国学生将参与多学科研究，以更好地了解和控制厄瓜多尔可可发酵的可变性。学生将学习研究方法、实验设计、化学分析、食品微生物学、感官分析和多元数据分析。每年，在为期三年的时间里，来自美国各地的两名研究生和两名本科生将在厄瓜多尔瓜亚基尔的一个多样化团队中沉浸8周。学生将由来自佐治亚大学和厄瓜多尔生物技术研究中心(CBRE)的跨学科教师以及在厄瓜多尔拥有发酵业务的法国巧克力制造商KAOKA的质量经理指导。在这个国际产业界和学术界的合作中，学生将参与实验室和实地研究，在那里他们将进一步提高他们的科学、专业和社会文化技能。我们的研究目标是通过受控发酵始终如一地生产高质量的可可产品。每组的学生将致力于五个主题中的一个，这些主题旨在表征可变性的来源，利用它们，并设计将可变性降至最低的系统和程序。世邦魏理仕与科学导师和当地学生的研究活动包括使用代谢组学方法分析新鲜可可豆的化学成分，代谢组学方法包括先进的色谱方法和多变量分析。这种方法将有助于阐明原料的可变性，并将主要成分与发酵豆类的质量联系起来。在KAOKA，学生们将学习大型发酵设施的日常操作，并与技术人员和工人互动，设计和执行现场实验。学生将表征化学成分并分析微生物种群的进化，以确定测量和控制发酵进程的方法。学生还将分析不同发酵批次生产的巧克力的成分，以评估成分如何影响味道的复杂性和感官体验的持续时间，并制定产生最佳质量属性的方法。最后，根据之前的所有研究，一些参与者将为小农设计和优化一个小型发酵罐。这一教育资源的传播预计将激励来自少数群体和代表性不足群体的其他学生追求STEM职业生涯，并参与类似的经历。这项研究预计将使不断增长的美国手工巧克力行业受益，并最终帮助可可小农户和他们的社区。这一新知识可能会对其他地区其他可可品种的发酵产生积极影响，并有助于美国在发展中国家以科学为导向的发展努力中的领导地位。该项目由国际学生研究体验计划(IRES)和生物基础设施部联合资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Centered on the development of the complex flavor profile of fine flavor cacao during fermentation, this IRES aims at enhancing the global and scientific competency of the student participants. This program promotes the participation of minorities and underrepresented students in STEM disciplines. The craft chocolate industry has grown rapidly over the last decade in the US and other parts of the world. The global trade of fermented and dried cocoa beans affects the lives of millions of individuals from cacao growers to chocolate manufacturers and the consumer. About 5% of the cacao produced in the world is from varieties that produce high quality chocolate, with Ecuador as one of the largest producers of such varieties. However, the large variability in the quality of fermented beans affects the quality, acceptability, and value of the chocolate produced. The variability in the quality of fermented cacao also lowers the price that local cacao growers, mostly smallholders, are paid. Despite its impact on flavor, of all the stages of chocolate production, cacao fermentation remains the most complex and the least studied. In this IRES project, U.S. students will participate in multidisciplinary research to better understand and control the variability of cacao fermentation in Ecuador. Students will learn research methods, experiment design, chemical analysis, food microbiology, sensory analysis, and multivariate data analysis. Every year, for three years, cohorts of two graduate and two undergraduate students from across the U.S. will be immersed for 8 weeks in a diverse team in Guayaquil, Ecuador. Students will be mentored by cross-disciplinary faculty from the University of Georgia, and from the Center for Biotechnology Research of Ecuador (CBRE), as well as by the quality manager at KAOKA, a French chocolate manufacturer with fermentation operations in Ecuador. In this international industry-academia collaboration, students will participate in laboratory and field research where they will further their scientific, professional, and sociocultural skills. Our research goal is to consistently produce high-quality cocoa products through controlled fermentations. Students from each cohort will work on one of five subthemes that aim at characterizing the sources of variability, harnessing them, and designing systems and procedures that minimize variability. Research activities with scientific mentors and local students at CBRE include analyzing the chemical composition of fresh cocoa beans using a metabolomics approach that encompasses advanced chromatographic methods and multivariate analysis. This approach will help elucidating the variability of the raw material and correlating the principal components to the quality of the fermented beans. At KAOKA, students will learn the daily operation of a large fermentation facility and interact with technical staff and workers to design and execute field experiments. Students will characterize the chemical composition and analyze the evolution of the microbial populations to identify means of measuring and controlling the progress of the fermentation. Students will also analyze the composition of chocolate produced from different fermentation batches to assess how composition affects the flavor complexity and the duration of the organoleptic experience and strategize means of producing the best quality attributes. Finally, informed by all the previous studies, some of the participants will design and optimize a small-scale fermenter for smallholders. The dissemination of this IRES is expected to inspire other students from minorities and underrepresented groups to pursue STEM careers and participate in similar experiences. This research is expected to benefit the growing U.S. craft chocolate industry and contribute to eventually help cacao smallholders and their communities. This new knowledge likely to positively impact the fermentation of other cacao cultivars in other regions and to contribute to the U.S. leadership in science-driven development efforts in developing countries.This project is jointly funded by the International Research Experiences for Students program (IRES) and the Division of Biological Infrastructure.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.