Flavor chemical

New and revised specifications for flavor chemicals follow in tabular format. The following Explanatory Notes, given in the Fourth Edition, are unchanged  

Note 3 (Solubility in Alcohol) Determine the solubility in alcohol at 25° as directed in the general method, Appendix VI, Essential Oils and Flavors. 

Note 4 (I.D.) The notation IR in the identification (I.D.) column indicates that an infrared absorption spectrum is provided for the particular substance in the section entitled Infrared Spectra. Where the IR requirement is specified, the infrared absorption spectrum of the sample shall exhibit maxima at the same wavelengths (or frequencies) as those shown in the respective spectrum, using the test conditions as specified therein. 

Note 5 (Assay) Assay requirements are specified as minimum values (unless a range of assay values is given) and are stated in weight percent unless otherwise indicated. References to assay methods are indicated by citations in parentheses, e.g., (M-la) to methods provided under Test Methods for Flavor Chemicals. 

Note 6 (A.V.) Unless otherwise indicated, determine the acid value (A.V.) as directed in M-16, using phenolphthalein TS as the indicator unless another indicator is specified for an individual substance. Where Method II is specified, determine the acid value as directed in the general method, Appendix VII, Fats and Related Substances. 

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S. Arctander, Pefume and Flavor Chemicals, 2 Vols., S. Arctander, Montclair, N.J., 1969. 

Nearly all of the benzal chloride produced is consumed in the manufacture of benzaldehyde. Benzaldehyde (qv) is used in the manufacture of perfume and flavor chemicals, dyes, and pharmaceuticals. The principal part of benzotrichloride production is used in the manufacture of benzoyl chloride (see Benzoic acid). Lesser amounts are consumed in the manufacture of benzotrifluoride, as a dyestuff intermediate, and in producing hydroxybenzophenone ultraviolet light stabilizers. Benzotrifluoride is an important intermediate in the manufacture of herbicides, pharmaceuticals, antimicrobial agents, and the lampreycide, 4-nitro-3-(trifluorometh5l)phenol [88-30-2]. 

Animal tissues, absorption and deposition of conjugated dienoic isomers of linoleic acid, 263-268 Anosmias, flavor chemicals, 19,2U Anticarcinogenic activity, conjugated dienoic derivatives of linoleic acid, 268-269... 

The number of synthetically produced fragrance and flavor chemicals has since expanded continually as a result of the systematic investigation of essential oils and fragrance complexes for odoriferous compounds. Initially, only major components were isolated from natural products their structure was then elucidated and processes were developed for their isolation or synthesis. With the development of modern analytical techniques, however, it became possible to isolate and identify... 

Among the acyclic terpene aldehydes, citral and citronellal hold key positions as fragrance and flavor chemicals, as well as starting materials for the synthesis of other terpenoids. Hydroxydihydrocitronellal is one of the most important fragrance materials. Derivatives of these aldehydes, particularly the lower acetals, are also used as fragrance materials. Acyclic sesquiterpene aldehydes are not very important as such, but they contribute to the characteristic fragrance and aroma of essential oils, for example, in the case of a- and /3-sinensal in sweet orange oil. 

Arctander S (1969) Perfume and flavor chemicals. Aroma chemicals. Arctander, Montclair... 

Arctander, S. "Perfume and Flavor Chemicals" Steffen Arctander, Publisher, 1969 Vol. I and II. 

Arctander, S. ed. Perfume and Flavor Chemicals (Aroma Chemicals), Montclair, NJ,... 

The most common method for the separation and concentration of flavor chemicals before chromatography is solvent extraction. If the aroma active components in a sample are less than a microgram/liter then solvent extraction followed by fractional distillation can be used to concentrate the analytes above 1 4g/liter. This is done for two reasons (1) to remove the odorants from some of the interfering substances and nonvolatiles, and (2) to concentrate the sample for greater sensitivity. The choice of solvent(s) depends on a number of issues, but similar results can be obtained with many solvents. Table Gl.1.2 lists a number of solvents, their polarity, and physical properties. Pentane is the least polar and ethyl acetate the most. The sample must be an aqueous or dilute sample, dissolved or slurried into water to a final concentration of 80% to 90% water. Dilute aqueous samples will present the greatest polarity difference between the solvent and the sample, driving more volatiles into the extracting solvent. 

Textbook on food chemistry with an excellent discussion of flavor chemicals. 

O. Seconding Handbook of Perfumes and Flavors, Chemical Publishing Co., Inc., New York, 1990. 

Volatile Flavor Chemicals Formed by the Maillard Reaction... 

The Maillard reaction has received much attention since the 1950 s as the source of flavor chemicals in cooked foods. Numerous compounds produced by this reaction have been reported in the last two decades. The major flavor chemicals are nitrogen- and sulfur-containing heterocyclic compounds. For example, nitrogen-containing pyrazines contribute a characteristic roasted or toasted flavor to cooked foods. Sulfur-containing thiophenes and thiazoles give a characteristic cooked meat flavor. A striking property of these compounds is their extremely low odor thresholds. 

In addition to simple model systems, more complex systems which are closer to actual foodstuffs have been used to investigate the formation of flavor chemicals in the Maillard reaction. Sixty-three volatile chemicals were isolated and identified from starch heated with glycine (4). When beef fat was used as a carbonyl compound precursor in a Maillard model system with glycine, 143 volatile chemicals were identified (6). These included fifteen n-alkanes, twelve n-alkenes, thirteen n-aldehydes, thirteen 2-ketones, twelve n-alcohols, and eleven n-alkylcyclohexanes. Recently, the effect of lipids and carbohydrates on the thermal generation of volatiles from commercial zein was studied (7). 

Pyrazines are the major volatile flavor chemicals produced in Maillard reactions. The discovery of this role of pyrazines was one of the most significant advances in flavor chemistry and two comprehensive reviews of pyrazines have appeared (25, 26). In the 1970 s, pyrazines were well-characterized as the compounds which directly contribute to roasted or smoky flavors. Some pyrazines possess an extremely low odor threshold (25, 29). For example, odor threshold of 2-isobutyl-3-methoxypyrazine in water is 0.002 ppb. 

Many individual flavor chemicals which were isolated and identified from Maillard "side reactions" have been reported in the patent literature. It is evident from these patents that much work has been done to glean specific flavor chemicals from the complexities of the Maillard reaction. 3-Furyl alkyl sulfide, disulfide, and 0-chalcogenalkyl sulfide derivatives are claimed to provide bloody, meaty, and roasted notes to beef broth and beef products (64-66). 3-Methylcyclopent-2-en-l-one was declared for its flavor eiiEancement of beef bouillon (67). Firmenich claimed 2,6-dimethyl-2-octenal and its analogs as possessing meat flavor qualities (68). A method to produce disulfides for application to meat and savory flavors was patented (69). 

The experimental design included commonly-used flavor chemicals alcohols, aldehydes, ketones, compounds and hydrocarbons. 

Arctander, S., "Perfume and Flavor Chemicals" S. Arstander, Publisher, Elizabeth, N.J. (1969). 

Traditionally the several thousand aroma chemicals used by perfumers have included many for which aggregate world demand is on the order of a few tons per year or less. These were produced primarily by the small specialty manufacturers that are now disappearing. The range of aroma chemicals available for perfume creation is bound to shrink. Already many of the materials described in Arctander s standard book Perfume and Flavor Chemicals (1969) are no longer ob-... 

Leffingwell, J. C., and Leffingwell, D. 1991. GRAS flavor chemicals—detection thresholds. Perfumer and Flavorist 16(1) 1—19. 

The titles of FCC monographs are in most instances the common or usual names. The FCC specifications apply equally to substances bearing the main titles, synonyms listed under the main titles, and names derived by transposition of definitive words in main titles. The Committee on Food Chemicals Codex recognizes that the nomenclature used for flavor chemicals may not be consistent with other authoritative sources. 

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