Omonrice 12: 157-161 (2004) SHORT COMMUNICATION PROMISING NEW TECHNOLOGIES FOR CLASSIFYING AROMATIC RICES Gay, F. 1 , Mestres, C. 1 , Cao Van Phung 2 , Nguyen Thi Lang 2 , Do Khac Thinh 3 , Laguerre, M. 1 , Boulanger, R. 1 , Davrieux, F. 1 ABSTRACT Semi-quantitative methods based on Solid Phase Micro Extraction/Mass Spectroscopy (SPME/MS) and Near Infrared Spectrometry (NIRS) were used to evaluate the aroma of the grain of 53 samples including 48 samples of aromatic rices (Nang Thom Cho Dao and OM3536) collected in Viet Nam and 5 samples of non-aromatic rices from France. Results show that both methods allow to distinguish aromatic varieties from non aromatic ones. Furthermore, analysis with SPME/MS allows as well to discriminate the 2 aromatic varieties used in this work. Further works are needed to improve the methods. 1 French Agricultural Research Center for International Development, CIRAD, France 2 Cuu Long Rice Research Institute, CLRRI, Vietnam 3 Institute of Agricultural Science of South Vietnam, IAS, Vietnam INTRODUCTION Since the middle of the nineties, Viet Nam has been more and more concerned with the production of aromatic rice as it may contribute to support the competitivity of Vietnamese rice on both domestic and international markets, and to increase rice farmers’ income due to higher price paid to this rice compare to ordinary rice. A lot of aromatic varieties are available in Viet Nam. Three types could be distinguished : traditional, improved and exotic (Nghia et al., 2001). Traditional varieties have been neglected for a long time because they were not suitable for intensive production due to their long growth duration and low yield. However, as their grain quality is highly appreciated by Vietnamese people, they are paid more attention, especially Nang Thom Cho Dao (NTCD) in the Mekong Delta and Tam Xoan in the Red River Delta. Improved varieties are modern varieties with short growth duration and high potential yield. The most famous are Jasmine 85, VD20 and OM3536. At last, the exotic type concerns the two well known aromatic varieties grown in the world : Khao Dawk Mali 105 (KDML105) from Thailand and Basmati 370 from India. KDML105 has been successfully introduced and cropped in the Mekong Delta for many years while the adaptation of Basmati 370 hasn’t been achieved so far. Despite this genetic potential, several socio- economic and technical factors hampered the production of aromatic rice in Viet Nam. The most important issue is the variation of grain quality, especially aroma intensity, with the agro-ecological conditions which limits the extension of this production. For instance, outside its narrow native area, NTCD variety loses its aroma and the grain quality doesn’t meet the consumer taste. The same trend is observed for KDML105 which performs better in coastal areas than in central ones (Bui Chi Buu, 2000). On the socio-economic point of view, good planning of aromatic rice production and breeding of appropriate varieties matching the demand is limited by the lack of knowledge on consumers’ preferences. Basic research works including several disciplines (agronomy, crop physiology, breeding and food technology) are required to tackle these issues. A common limit to the research works on aroma is the way aromatic level is assessed. Sensory method used by breeders is very rapid but insufficiently sensitive and reproducible. 2-acetyl-1-pyrroline, one of the