The Impact of Cocoa Processing on Flavanol Content Absorption and Health Effects

饮食是最重要的生活方式因素之一，饮食会强烈影响心血管疾病的发病率，因此健康的饮食对健康老龄化至关重要。最近的饮食干预研究，特别是那些使用葡萄酒、茶和可可的研究，证明了在降低心血管疾病风险方面的有益效果，包括降低血压和防止血管老化的能力。虽然这些食品和饮料在化学成分、营养含量和每份卡路里上存在很大差异，但它们有一个共同点，即它们是一组被称为黄烷醇的植物化合物的主要饮食来源之一。黄烷醇的有益作用归因于它们被吸收到血液中并对血管产生直接作用的潜力。虽然富含黄烷醇的食物可以被认为对心血管疾病具有保护作用，但在工业加工过程中，活性黄烷醇的含量会显著减少。这是因为在加热和储存过程中，黄烷醇会不同程度地与糖反应，形成称为黄烷醇-美拉德结合物的新产品。目前，关于这些新的结合物的吸收以及它们是否具有与天然黄烷醇类似的有益性质的信息缺乏。这项建议旨在解决这些问题，并揭示工业食品加工对其固有健康特性的重要性。提案完成后，我们将处于一个极好的位置，向富含黄烷醇的食品制造商提供建议，说明生产出对心血管有最佳益处的食品所需的最佳加工条件。在我们实验室现有人类工作的基础上，这项多学科研究旨在：1)调查黄烷醇-美拉德产品在一种常见的富含黄烷醇的食物，即可可的加工过程中的形成；2)确定这些化合物在人体胃、小肠和大肠中的去向；以及3)评估它们对人体细胞产生有益影响的能力。第一个目标将告诉我们富含黄烷醇的食品在加工过程中形成的主要黄烷醇-美拉德结合物，在这种情况下，在烘焙过程中加热可可豆。虽然我们将研究可可，但热处理与许多其他富含黄烷醇的食物相关，因此将具有更广泛的相关性。其次，我们将通过给人类喂食加工可可并测量它们在血液中的含量来检查这些结合物以及天然黄烷醇的吸收情况。这将告诉我们，热处理是否会减少天然黄烷醇的吸收，以及黄烷醇-美拉德结合物是否会被人类吸收。我们还将研究它们在大肠中的新陈代谢，以及它们是否对肠道微生物群的平衡有有益的影响，类似于生物前功能食品的变化。最后，我们将使用最先进的分子技术来检验这些结合物在人类结肠癌和心血管疾病细胞模型中的有益作用。我们预测，这项提议将有助于确定生产能够发挥最强心血管保护作用的富含黄烷醇的食品所需的最佳工业加工条件。它将为行业和消费者提供信息，并将帮助我们制定未来战略，最大限度地提高我们食品中的黄烷醇含量。这项建议将扩大对饮食在预防心血管疾病中所起作用的理解，并将有助于为应对心血管疾病的新的、有前途的饮食策略提供证据。因此，这项研究的结果对老龄化人口具有重要意义，因为在老龄化人口中，健康老龄化状况亟需改善。此外，生活质量方面的潜在好处与整个人口有关，医疗保健费用的潜在节省也是如此。

Representing one of the most important lifestyle factors, diet can strongly influence the incidence of cardiovascular disease and thus a healthy diet is crucial for healthy ageing. Recent dietary intervention studies, in particular those using wine, tea and cocoa, have demonstrated beneficial effects on reducing cardiovascular disease risk, including an ability to lower blood pressure and to prevent blood vessel ageing. While such foods and beverages differ greatly in chemical composition, nutrient content and calories per serving, they have in common that they are amongst the major dietary sources of a group of plant compounds known as flavanols. The beneficial effects of flavanols have been attributed to their potential to be absorbed into the blood and to exert direct actions on blood vessels. Whilst flavanol-rich foods can be regarded as being protective against cardiovascular disease, the content of active flavanols is significantly reduced during industrial processing. This is because during heating and storage, the flavanols react with to varying degrees with sugars to form new products known as flavanol-Maillard conjugates. At present, information regarding the absorption of these new conjugates and whether they possess similar beneficial properties to native flavanols is lacking. This proposal is designed to address these questions and to unravel the significance of industrial food processing on their inherent health properties. On completion of the proposal, we will be in an excellent position to advise manufacturers of flavanol-rich foods on the best processing conditions required to produce foods with optimum beneficial cardiovascular effects. Building on existing human work conducted in our laboratory, this multidisciplinary study is designed to: 1) investigate the formation of flavanol-Maillard products during the processing of a common flavanol-rich food, namely cocoa; 2) determine the fate of these compounds in the human stomach, small intestine and large intestine; and 3) assess their ability to exert beneficial effects human cells. The first objective will inform us of the major flavanol-Maillard conjugates formed in the flavanol-rich foods during the processing, in this case heating of the cocoa beans during roasting. Although we will study cocoa, heat processing is relevant to many other flavanol rich-foods and therefore will have wider relevance. Secondly, we will examine the absorption of these conjugates, along with native flavanols by feeding processed cocoa to human and measuring them in blood. This will tell us whether heat processing reduces the absorption of native flavanols and also whether the flavanol-Maillard conjugates are absorbed by humans. We will also investigate their metabolism in the large intestine and whether they have a beneficial effect on the balance of the gut microflora, akin to changes seen with pre-biotic functional foods. Lastly, we will examine the beneficial effects of the conjugates in cellular models of human colon cancer and cardiovascular disease using state-of-the-art molecular techniques. We predict that this proposal will help determine the optimum industrial processing conditions required to generate flavanol-rich foods capable of exerting the strongest cardiovascular protection. It will inform both industry and the consumer and will help us develop future strategies to maximise flavanols in our foods. The proposal will broaden understanding of the role that diet plays in the prevention of cardiovascular disease and will help provide evidence for new and promising dietary strategies for tackling cardiovascular disease. The results of this study therefore have important implications for an ageing population where an improvement in healthy ageing is greatly desired. Moreover, the potential benefits in terms of quality of life are relevant to the population as a whole, as are the potential savings in health care costs.