Pemetaan Pengaruh Proses Pengolahan pada Kualitas Biji Kakao Menggunakan Metode Metabolik Profiling dengan GC/MS

Abstract MAPPING THE EFFECTS OF COCOA POST HARVEST PROCESSING ON COCOA BEAN QUALITY BY METABOLIC PROFILING METHOD USING GC/MS. The quality of cocoa is strongly effected by the implemented post harvest processes. The fermented cocoa beans is presumed to have higher quality than the unfermented ones, whereas roasting strongly affects the organoleptic quality of the cocoa products. However, what exactly differentiates those cocoa beans are not known yet. This research was foccused on the mapping of post harvest processing method on the quality of cocoa beans, using metabolic profiling method. Different types of cocoa bean samples, that were fermented, roasted, fermented and roasted, as well as unfermented and unroasted (as control) were analysed by GC-MS. The obtained metabolic profiles were further mapped using Principal Component Analysis (PCA). The results showed that there were significant different on samples processed through different processing methods. The fermentation and roasting of cocoa beans direct the process such that more homogenous metabolic composition were obtained. Kata kunci: cocoa beans; fermentation; metabolomic; PCA; processing; roasting Abstract Proses pengolahan biji kakao sangat menentukan kualitas kakao yang dihasilkan. Biji kakao terfermentasi diyakini memiliki kualitas yang lebih tinggi dibandingkan biji kakao tanpa fermentasi. Proses penyangraian juga diyakini sangat menentukan kualitas organoleptik produk olahan kakao. Akan tetapi, para pelaku bisnis kakao masih belum mengetahui secara pasti apa yang membedakan hal tersebut. Penelitian ini berfokus pada pemetaan pengaruh proses pengolahan pada kualitas biji kakao, menggunakan metode metabolik profiling. Sampel biji kakao dengan berbagai proses pengolahan: difermentasi, disangrai, difermentasi dan disangrai, serta kontrol (tidak difermentasi dan tidak disangrai) dianalisa dengan GC/MS untuk memetakan komposisi metabolitnya. Spektrum metabolit yang diperoleh kemudian dipetakan menggunakan metode Principal Component Analysis (PCA). Hasil yang diperoleh menunjukkan terdapat perbedaan yang signifikan antara sampel dengan berbagai proses pengolahan tersebut, pengolahan biji kakao yang terdiri dari fermentasi dan penyangraian mengakibatkan komposisi biji kakao yang lebih seragam. Keywords: biji kakao; fermentasi; metabolomik; PCA; pemrosesan; penyangraia