Natural Products & Food Research and Analysis (NatuRA), Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
Cacaolab bvba, Evergem, Belgium.
Food Res Int. 2020 Apr;130:108943. doi: 10.1016/j.foodres.2019.108943. Epub 2019 Dec 24.
Cocoa products are obtained from the seeds of Theobroma cacao L. In this research, cocoa liquor and chocolate produced from cocoa beans from West Africa (Forastero, "bulk" cacao) and Ecuador (Nacional variety, "fine-flavor" cacao), were investigated, using a novel approach in which various analytical techniques are combined in order to obtain in-depth knowledge of the studied cocoa samples. The levels of various classes of primary metabolites were determined and a wide range of secondary metabolites, including volatile organic acids, aldehydes, esters, pyrazines, polyphenols, methylxanthines and biogenic amines, were identified and/or quantified by HS-SPME GC-MS (headspace-solid phase microextraction gas chromatography - mass spectrometry). and UPLC-HRMS (ultra-performance liquid chromatography - high resolution mass spectrometry). Odor Activity Values (OAV) were calculated to assess the contribution of individual volatiles on the final aroma. Various volatile aroma compounds were more abundant in the West African cocoa liquor and chocolate, while the Ecuadorian samples were richer in most quantified non-volatile metabolites. Principal component analysis (PCA) confirmed that the four samples can be clearly distinguished. Alcohols, pyrazines, amino acids and biogenic amines were found to be highly influential in causing this differentiation. The proposed approach can be useful in future studies on more extensive cocoa sample collections, in order to highlight similarities and pinpoint typical differences in chemical composition among these samples.
可可制品是由可可树(Theobroma cacao L.)的种子制成的。在这项研究中,使用了一种新方法来研究来自西非(Forastero,“大宗”可可)和厄瓜多尔(Nacional 品种,“优质”可可)的可可豆制成的可可液和巧克力,该方法结合了多种分析技术,以深入了解所研究的可可样品。测定了各种初级代谢物的水平,并通过 HS-SPME GC-MS(顶空固相微萃取气相色谱-质谱)和 UPLC-HRMS(超高效液相色谱-高分辨率质谱)鉴定和/或定量了广泛的次级代谢物,包括挥发性有机酸、醛、酯、吡嗪、多酚、甲基黄嘌呤和生物胺。计算了气味活度值(OAV)以评估单个挥发性物质对最终香气的贡献。各种挥发性香气化合物在西非可可液和巧克力中更为丰富,而厄瓜多尔样品中大多数定量的非挥发性代谢物更为丰富。主成分分析(PCA)证实了这四个样品可以清楚地区分。醇、吡嗪、氨基酸和生物胺被发现对这种差异有很大的影响。拟议的方法可用于对更广泛的可可样品进行未来研究,以突出这些样品之间在化学成分上的相似之处和典型差异。