Formation of Volatile Compounds

Another process employed to increase the formation of volatile compounds in fmit is that of bioregulators. When a bioregulator is appHed to lemon trees an increase in both the aldehyde and alcohol fractions of the lemon oil extracted from the fmit of the treated lemon trees was observed (78). 

Kanasawud, P. and Crouzet, J.C., Mechanism of formation of volatile compounds by thermal degradation of carotenoids in aqueous medium. 1. (3-Carotene degradation, J. Agric. Food Chem., 38, 237, 1990. 

Kanasawud and Crouzet have studied the mechanism for formation of volatile compounds by thermal degradation of p-carotene and lycopene in aqueous medium (Kanasawud and Crouzet 1990a,b). Such a model system is considered by the authors to be representative of the conditions found during the treatment of vegetable products. In the case of lycopene, two of the compounds identified, 2-methyl-2-hepten-6-one and citral, have already been found in the volatile fraction of tomato and tomato products. New compounds have been identified 5-hexen-2-one, hexane-2,5-dione, and 6-methyl-3,5-heptadien-2-one, possibly formed from transient pseudoionone and geranyl acetate. According to the kinetics of their formation, the authors concluded that most of these products are formed mainly from all-(E) -lycopene and not (Z)-isomers of lycopene, which are also found as minor products in the reaction mixture. 

The manufacture of packaging materials is often conducted under conditions of high temperatures. A burnt polyethylene odor has been experienced in the paper/foil/ polyethylene laminate field. These conditions can easily induce thermal degradation with the formation of volatile compounds in packaging materials (8-131. 

Formation of Volatile Compounds from Extruded Corn-Based Model Systems... 

The formation of volatile compounds by the Maillard reaction has been most recently reviewed by Mottram152 and Tressl and Rewicki.30... 

Garde-Cerdan, X, Ancm-Azpilicueta, C. (2006) Contribution of wild yeasts to the formation of volatile compounds in inoculated wine fermentations. European Food Research and Technology, 222, 15-25. 

Figure 15. Formation of volatile compounds with toasty aromas by Maillard reactions between sugar molecules and amino acid residues when wood is heated...

Sensory evaluation of lipid oxidation has been conducted by many researchers (98-100). However, as a subjective method, the reproducibility of sensory analysis is generally considered worse than that of chemical or instrumental methods. More recently, use of an electronic nose to monitor the formation of volatile compounds associated with off-flavors from hpid oxidation has been proposed to supplement information from human sensory panels (101). 

In Vienna a case of chronic antimony poisoning occurred in a house with silk curtains containing a mordant with a compound of antimony. A series of experiments was performed to detect the possible formation of volatile compounds of antimony, but the speciation of the volatile antimony compound has been unsuccessful . 

Barbarin, N. Rollmann, B. Tilquin, B. Role of residual solvents in the formation of volatile compounds after radio sterilization of cefotaxime. Int. J. Pharm. 1999, 178, 203-212. 

Donors such as elemental S, Se, Te, or Sn diffuse into GaAs . With S, alloying and formation of sulfides occurs during diffusion, producing surface erosion of Si wafers. Similar problems occur with GaAs, since both donor elements and As are reactive and volatile. In the presence of S, the transport of As and Ga from the surface of GaAs wafers is enhanced by formation of volatile compounds . 

Enzymic Formation of Volatile Compounds in Shiitake Mushroom (Lentinus edodes Sing.)... 

Aleksandrov et al. [292] reported a study of the processes of rare-earth metal oxide chlorination by CCI4 at 200-840 °C. A quartz container does not react with CCI4 up to 750 °C, but heating to higher temperatures causes a decrease in the container s mass owing to the formation of volatile compounds of silicon according to the following reaction ... 

Kanasawud [13] have proposed a mechanism for the formation of volatile compounds of saffron by thermal degradation of carotenoids including a-carotene (VI) and lycopene (VII) degradation. 

Story WC and Caruso JA (1992) Preconcentration by formation of volatile compounds. In Alfassi ZB and Wai CM, eds. Preconcentration Techniques for Trace Elements, pp. 333-362. CRC Press, Boca Raton. 

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