4- Hydroxy-5-methyl-3 -furanone identification

Nunomura N., Sasaki M., Asao Y. and Yokotsuka T. (1976) Isolation and identification of 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2//)-furanone, as a flavor component in shoyu (soy sauce). Agric. Biol Chem. 40, 491-5. 

Matsukura, M., K.Takahashi, M. Kawamoto, S. Ishiguro, and H. Matsushita Identification of 3-hydroxy-4,5-di-methyl-2-(57/)-furanone (Sotolone) in roasted tobacco volatiles Agr. Biol. Chem. 49 (1985) 3335-3337. Matsumoto, T., G. Sakata, Y. Tachibana, and K. Fukui Stereochemistry of nucleophilic addition. fV. Condensation of 2,2,6-trimethylcyclohexanone with tert-butyl acetate in the presence of lithium amide Bull. Chem. Soc. Japan 45 (1972) 1147-1152. 

Identification. Purification and identification of M-1 and M-2 as 2,3-dihydro-3,5-dihydroxy-6-mefliyl-4(H)-pyran-4-one and 4-hydroxy-5-methyl-3(2H)-furanone, respectively, by mass spectrometry have been pubUshed (7,77). Analysis of different types of foods heated similarly at sterilizing temperatures revealed that M-1 is formed in meats and vegetables and M-2 is formed in meats only. Another compound, S-hydroxymediylfiirfural, appears to be a useful marker in heating fruits and fruit juices (M-3X7). 

Figure 21 shows a comparison of the neutral cheese fractions isolated not only by SAFE but also by the SDE technique. There were differences in both the qualitative and quantitative composition. Many heat-induced alterations of the aroma profile in the SDE sample were observed (data not presented). Identification of cheese volatiles was based on GC/MS. We found, based on our spectroscopic investigation of the acidic fraction, that the SAFE technique was more effective in extracting less volatile and polar constituents such as 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 4-hydroxy-5-methyl-3(2H)-furanone, and 5-ethyl-4-hydroxy-2-methyl-3(2H)-furanone. As a result, it should be possible to quantify these organoleptically important trace constituents by special techniques—e.g.,... 

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