Chair of Food Chemistry and Molecular Sensory Science, Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising-Weihenstephan, Germany.
Leibniz-Institute for Food Systems Biology at the Technical University of Munich, Lise-Meitner-Str. 34, D-85354 Freising-Weihenstephan, Germany.
J Agric Food Chem. 2021 Jul 28;69(29):8200-8212. doi: 10.1021/acs.jafc.1c01987. Epub 2021 Jul 19.
Historically often described as the food of gods, cocoa-based products exhibit a pleasant aroma as well as a desirable astringent, bitter, and sour taste, which results in a high consumer preference. The key taste components of cocoa were identified and characterized by combining sensory analysis, fractionation, and structure elucidation. Cocoa astringency is driven by -phenylpropenoyl-l-amino acids, polyphenol glycosides, and flavan-3-ols, while the latter compound class also contributes to bitterness. The key principle for cocoa bitterness was shown to be the combination of alkaloids and 2,5-diketopiperazines. To understand the influence of plant genetics, breeding, and processing on the sensory profile of cocoa products, high-throughput sensometabolite quantitation must be performed throughout all of these steps. In this work, we present a rapid, sensitive, and robust quantitation method on a single ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) platform, requiring minimal workup for any sample type from farm to fork. This method was applied to a global set of 75 cocoa bean samples from all over the world before and after using a uniform roasting protocol. Within this world map, geographical origin did not predetermine cocoa taste profiles, whereas simulated processing by roasting was confirmed to be crucial in profile development. This method will open avenues for further studies to ultimately enable chocolate producers to control and optimize the taste properties of products as well as to monitor raw material selection and processing.
从历史上看，可可制品常被描述为“众神的食物”，其具有宜人的香气和令人愉悦的涩味、苦味和酸味，这导致了消费者的高度偏好。通过感官分析、分级和结构阐明相结合，确定并描述了可可的关键味觉成分。可可的涩味是由 - 苯丙酰基 -l- 氨基酸、多酚糖苷和黄烷 -3- 醇驱动的，而后者化合物类也有助于产生苦味。可可苦味的关键原理被证明是生物碱和 2,5-二酮哌嗪的组合。为了了解植物遗传学、育种和加工对可可产品感官特征的影响，必须在所有这些步骤中对高通量敏感代谢物进行定量。在这项工作中，我们提出了一种快速、灵敏和强大的定量方法，在单个超高效液相色谱串联质谱 (UHPLC-MS/MS) 平台上进行，任何类型的样品（从农场到餐桌）都只需最少的预处理。该方法应用于来自世界各地的 75 个可可豆样品，这些样品在使用统一的烘焙方案前后都进行了处理。在这个世界地图中，地理起源并不能预先确定可可的口味特征，而模拟加工（烘焙）被证实是在特征发展中至关重要的。该方法将为进一步的研究开辟道路，最终使巧克力生产商能够控制和优化产品的口感特性，并监测原料选择和加工。
