Abstract Nacional is a worldwide recognized Ecuadorian cocoa variety. However, little is known regarding its phytochemical profile and how the production area influences its nutritional quality. The contents of methylxanthines (caffeine and theobromine), total polyphenols, flavan-3-ols monomers (catechin and epicatechin) and main proanthocyanidins (procyanidins B2 and C1) in beans of Nacional cocoa were evaluated. A comprehensive sampling was carried out along Ecuador, including 85 farms from three different geographical levels (region, province, and canton). Theobromine and caffeine contents were higher in cocoas from the Amazonian region. According to the caffeine/theobromine ratio, all samples were classified as Trinitario cocoa. The flavan-3-ols amount was not clearly associated to a geographical area. However, when principal component analysis was applied, common patterns were found for some provinces. These results may be useful to further characterize the composition of cocoa beans for quality and authenticity purposes and the development of chocolate products rich in bioactives.

中文翻译：

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产地对厄瓜多尔可可豆甲基黄嘌呤和黄烷-3-醇含量的影响

摘要 Nacional 是世界公认的厄瓜多尔可可品种。然而，关于其植物化学特征以及产区如何影响其营养质量知之甚少。评估了 Nacional 可可豆中甲基黄嘌呤（咖啡因和可可碱）、总多酚、黄烷-3-醇单体（儿茶素和表儿茶素）和主要原花青素（原花青素 B2 和 C1）的含量。沿厄瓜多尔进行了全面抽样，包括来自三个不同地理级别（地区、省和州）的 85 个农场。来自亚马逊地区的可可中的可可碱和咖啡因含量较高。根据咖啡因/可可碱的比例，所有样品都被归类为 Trinitario 可可。flavan-3-ols 的量与地理区域没有明显的关联。然而，在应用主成分分析时，发现了一些省份的共同模式。这些结果可能有助于进一步表征可可豆的成分，以达到质量和真实性的目的，以及开发富含生物活性成分的巧克力产品。