PHÂN TÍCH XÁC ĐỊNH THÀNH PHẦN DỄ BAY HƠI TRONG MỘT SỐ LOẠI GẠO VIỆT NAM

Tóm tắt

Sengcu rice is highland speciality that has gaining popularities recently. Various authentication
methods for the discrimination of high-quality Sengcu rice have been proposed; however, those relying
on aromatic properties have not yet been proposed. In this study, an analysis is presented for the
determination of volatile aromatic compounds (VAC) in rice using solid-phase microextraction
combined with gas chromatography-tandem mass spectrometry. The method was then applied for the
delimitation of Sengcu rice from other rice types including ST25, Tam, Bac Huong, Jasmine collected
from several markets in Hanoi, Vietnam. The results show that in total, there were 48 VACs detected
from rice samples. Principal component analysis extracted 16 PCs explaining more than 70% of the
total variance, in which PC1 and PC2 explained 14.23% and 5.9% of the total variance, respectively.
Partial least square-discriminant analysis (PLSDA) clearly separated Sengcu from other rice types
based on their VAC composition. Generalized linear model for the principal-component-transformed
intensity exhibited significant difference between Sengcu and other rice types. In particular, Sengcu
rice stood out as the most significantly different one, whereas there was no significant difference
detected among other types. 2-acetyl-1-pyrroline, 3-hydroxymandelic acid and 6-methyl-5-hepten-2-
one were those compounds that mostly contributed to the difference among rice types. Further research
expanding the number of rice types and sample size would greatly contribute to this procedure for the
discrimination of Sengcu rice on the market.