Volatile profiles

Boyer M., Jemiolo B., Andreolini F Wiesler D. and Novotny M. (1989). Urinary volatile profiles of Pine Vole, M. pinetorum and their endocrine dependancy. J Chem Ecol 15, 649-662. 

Ma W.D., Wiesler D. and Novotny M.V. (1999). Urinary volatile profiles of the deermouse (Peromyscus maniculatus) pertaining to gender and age. J Chem Ecol 25, 417-431. 

Flowers of some orchids mimic both the appearance and sex pheromone of virgin females of certain species of bees or wasps. This sexual deception results in pollination by male hymenoptera that would not normally visit flowers. Japanese honey bee drones (Apis cerana japonica) cluster on the oriental orchid (Cymbidiumpumilum) while on their mating flights [ 134]. By comparing volatile profiles of orchids and the female hymenoptera they mimic, or by GC-EAD and GC-MS analysis of orchid volatiles, several compounds have been identified that may mediate this attraction for the solitary bee Andrena nigroaenea [135, 136] and the scoliid wasp Campsoscolia ciliata [135]. 

Fig. 1.4 Comparative male mouse urinary volatile profiles for (A) Mus domesticus and (B) Mus spicilegus by GC-MS with characteristic chemical structures...

Escriche, E, Chiralt, A., Moreno, J., and Serra, J.A. 2001a. Influence of osmotic treatment on the volatile profile of strawberry (Fragaria x ananassa var. Chandler). In Proceedings of the International Congress on Engineering and Food, ICEF 8 (J. Welti-Chanes, G.V. Barbosa-Canovas, and J.M. Aguilera, eds), Vol. 1, pp. 151-155. Technomic Publisher, Lancaster, PA. 

Talens, P., Escriche, I., Martinez-Navarrete, N., and Chiralt, A. 2002. Study on the influence of osmotic dehydration and freezing on the volatile profile of strawberries. J. Food Sci. 67, 1648-1653. 

Resistant hirsutum race stocks Texas No. 254 and 810 also are deficient of bisabolene and B-bisabolol stocks 810, 1055, and 1123 have greatly increased caryophyllene oxide contents and stock 953 has greatly reduced concentrations of caryophyl 1 ene, caryophyl 1 ene oxide, and humulene (Table II). It is tempting to attribute the known increased resistance to insects in the Texas race stocks to the changes in volatile profiles, but this hypothesis remains to be proven. 

Agricultural processing will still incorporate solvents. As an example, soybean flakes were extracted with supercritical carbon dioxide to produce a solvent-free, good-quality soybean oil. During the SFE process, volatile compounds were trapped on a porous polymer trap attached at the exhaust port of the SFE apparatus. The volatile profile obtained from the sorbent trap was found to be similar to the headspace profile from the SFE/soybean oil removed during the same extraction. In addition, crude soybean oil was heated in a stirred reactor and the volatiles, which were stripped by supercritical carbon dioxide in an attempt to improve oil properties, were collected on sorbent traps and analyzed by the above method for comparison. The described methodology permits the characterization of volatiles and semivolatUes in SEE soybean oil and can be used to monitor the extraction and quality of the resultant oil (Snyder and King, 1994). 

Many factors affect the volatile composition of fruit and vegetables, e.g. genetics, maturity, growing conditions and postharvest handling. Furthermore, preparation of the fruits and vegetables for consumption and the method for isolation of volatile compounds may change the volatile profile and key aroma compounds compared to non-processed fruits and vegetables. 

Solely on the basis of volatility profiles, fossil fuel burning is expected preferentially to transfer As, Hg, Cd, Sn, Sb, Pb, Zn, Tl, Ag, and Bi to the atmosphere (1). In a study designed to detect fallout from a major coal burner equipped with a precipitator, Klein and Russell (27) showed that Ag, Cd, Co, Cr, Fe, Hg, Ni, Ti, and Zn were deposited in the surrounding soil (115 sq mi), and with the exception of mercury, enrichment correlated with the respective metal concentrations in the coal. Mercury was more widely disseminated to the environment. Previous work has indicated that mercury exists primarily in the volatile phase of the flue gas and consequently as much as 90% bypasses the electrostatic precipitation control device (2). Bolton and co-workers have evidence that selenium and arsenic may present a similar problem (see Chapter 13). 

Rancidity measurements are taken by determining the concentration of either the intermediate compounds, or the more stable end products. Peroxide values (PV), thiobarbituric acid (TBA) test, fatty acid analysis, GC volatile analysis, active oxygen method (AOM), and sensory analysis are just some of the methods currently used for this purpose. Peroxide values and TBA tests are two very common rancidity tests however, the actual point of rancidity is discretionary. Determinations based on intermediate compounds (PV) are limited because the same value can represent two different points on the rancidity curve, thus making interpretations difficult. For example, a low PV can represent a sample just starting to become rancid, as well as a sample that has developed an extreme rancid characteristic. The TBA test has similar limitations, in that TBA values are typically quadratic with increasing oxidation. Due to the stability of some of the end-products, headspace GC is a fast and reliable method for oxidation measurement. Headspace techniques include static, dynamic and solid-phase microextraction (SPME) methods. Hexanal, which is the end-product formed from the oxidation of Q-6 unsaturated fatty acids (linoleate), is often found to be a major compound in the volatile profile of food products, and is often chosen as an indicator of oxidation in meals, especially during the early oxidative changes (Shahidi, 1994). 

Depending on the source, age, and condition of the food, the volatile profile will vary substantially. There are, however, certain com-... 

Table D2.2.2 Summary of Volatile Profiles from Various Meat Products... 

Ahn. D.U., Jo, C., and Olson, D.G. 1999. Volatile profiles of raw and cooked turkey thigh as effected by purge temperature and holding time before purge. J. Food Sci. 64 230-233. 

Beef and beef gels, volatile profiles, 537 (fable)... 

Chemistry, physical, of interfaces, 610-617 Chicken, volatile profile, 537 (table) Chiral-phase HPLC, lipoxygenase activity measurement, 412 Chlorophylls, content Cholesterol... 

EC 1.11.1.7) (68) and diphenol oxidase (EC 1.10.3.1) (69) have been identified. The potential role of pyruvic decarboxylase (EC 4.1.1.1) catalyzed reaction as a source of acetaldehyde and other aldehydes in juice was discussed (70). Raymond et al. (71) isolated the decarboxylase from orange juice sections and demonstrated that only 10 to 15% of the enzyme was in an active form. Since the purified enzyme was only active with pyruvic acid and 2-ketobutyric acid of the series of 2-ketoacids examined, they (71) concluded that the direct contribution of orange pyruvic decarboxylase to the orange volatile profile was limited to acetaldehyde and possibly propionaldehyde. 

We first became interested in this area from studying volatiles produced in model Maillard systems. Shibamoto and Russell ( 1, 2) studied model systems such as glucose/hydrogen sulfide/ammonia and reported volatile profiles which contained many of the... 

After classification, all port wines are matured in oak barrels for a period that depends on the style and category. The wines are subsequently matured in wood casks or vats if oxidative aging (contact with oxygen) is desired, or in bottle when reductive aging is intended (without contact with oxygen). These different aging procedures affect both the polyphenolic and volatile profile of the wines. 

Volatile profiles of raw and cooked-beef flavor samples, prepared by the procedures of Figure 1, were obtained after capillary GC and FPD. Although the identification of these sulfur containing compounds is as yet incomplete, the chromatograms demonstrated that there were a number of new sulfur compounds produced on cooking that were not present in the raw beef. Three prominent sulfur compounds were identified as markers in subsequent meat flavor deterioration experiments, namely, methional (13.2 min), methyl sulfone (13.8 min), and benzothiazole (25.3 min). Each compound produced an adequate mass spectrum for spectral library search and positive identification. 

The authors wish to thank Dr. Harold P. Dupuy, Visiting Professor, Dept, of Food Science, Virginia Polytechnic Institute and State University, Blacksburg, VA for volatile profiles analyses of grilled beef patties used in storage studies. Technical assistance by Mr. Charles James, Jr., is also recognized. 

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