Identification of flavor compounds in rambutan seed fat and its mixture with cocoa butter determined by SPME-GCMS

Abstract

Rambutan (Nephelium opossum L) is one of the most important tropical fruits that is originally found in Malaysia, Thailand, Philippines, Vietnam, Borneo and other countries in this region. The industrial processing of this fruit produces seeds and peels as waste materials. The aim of this work was to determine the flavor active compounds of rambutan seed fat (RSF) and its mixtures with cocoa butter (CB) after fermentation 6 days and roasting at 150 °C for 30 min in term of ester, alcohol, hydrocarbon, carboxylic acid, aldehyde, ketone and pyrazine compounds. The result showed total ester flavoring compounds increased in the range of 10.59%–16.49% in the RSF mixtures as compared to CB. Alcoholic flavoring compounds also found in the range of 10.03%–23.15% of the total flavor in CB and RSF mixtures respectively. The most important flavoring compounds, Pyrazine, 2,6-dimethyl (1.42% and 2.01%), Pyrazine, 2-ethyl-6-methyl (0.67% and 0.62%), Pyrazine, trimethyl (5.10% and 5.22%), Pyrazine, tetramethyl (14.34% and 14.72%), 2-Acetyl-3,5-dimethylpyrazine (0.56% and 0.45%), 2-Isoamyl-6-methylpyrazine (0.34% and 0.34%) and Pyrazine, 2-butyl-3,5-dimethyl (0.34% and 0.27%) estimated in CB and RSF mixtures respectively. Rambutan seed fat up to 20% can be used with cocoa butter as a potential ratio of CB and RSF for the application in chocolate manufacturing as a cocoa butter alternative to improve and get the best quality aroma in final products. Keywords: Rambutan seed fat, Cocoa butter, Ester, Alcohol, Pyrazines