| Abstrak/Abstract |
The aroma of rice essentially contributes to the quality of rice grains. For some varieties, their aroma properties really drive consumer preferences. In this paper, using a dynamic headspace solid-phase microextraction (HS-SPME) system coupled to a two-dimensional gas chromatography (GC× GC) using a time-of-flight mass spectrometric detector (TOFMS) and multivariate analysis, the volatile compounds of aromatic and non-aromatic rice grains were contrasted to define some chemical markers. Fifty-one volatile compounds were selected for principal component analysis resulting in eight key-marker volatile compounds (ie, pentanal, hexanal, 2-pentyl-furan, 2, 4-nonadienal, pyridine, 1-octen-3-ol and (E)-2-octenal) as responsible for the differences between aromatic and non-aromatic rice varieties. The factors that are most likely to affect the HS-SPME efficiency for the aforementioned key-marker compounds were evaluated using a 2 I I I 5? 2 fractional factorial design in conjunction with multi-response optimisation. The method precision values, expressed as% of coefficient of variation (CV), were ranging from 1.91% to 26.90% for repeatability (n= 9) and 7.32% to 37.36% for intermediate precision (n= 3× 3). Furthermore, the method was successfully applied to evaluate the volatile compounds of rice varieties from some Asian countries |
