Flavor Chemicals Benzaldehyde

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]. 

Table II lists 13 of the most commonly-used chemicals in the flavor industry. For example, cinnamic aldehyde is used for the generation of cassia or cinnamon flavors, carvone for spearmint flavors, citral for citrus flavors, and benzaldehyde for cherry flavors. As can be seen, the known s values for these compounds are...

Benzaldehyde Glyceryl Acetal View Flavor Chemical... 

He describes various essential oils that can be used as sources of specific natural flavor chemicals. Among them are leaf alcohol, benzaldehyde and tolualdehyde. This represents a technology which can be employed at the present time, since only classical isolation and separation techniques are required. 

Benzaldehyde is nsed as an intermediate in the prodnction of flavoring chemicals, such as cinnamaldehyde, cinnamalalcohol, and amyl- and hexylcinnamaldehyde for perfume, soap, and food flavor synthetic penicillin, ampicillin, and ephedrine and as a raw material for the herbicide Avenge. It occurs in nature in the seeds of almonds, apricots, cherries, and peaches. It occurs in trace amounts in com oil. 

Benzaldehyde. Annual production of ben2aldehyde requires ca 6,500—10,000 t (2-3 x 10 gal) of toluene. It is produced mainly as by-product during oxidation of toluene to benzoic acid, but some is produced by hydrolysis of ben2al chloride. The main use of ben2aldehyde is as a chemical intermediate for production of fine chemicals used for food flavoring, pharmaceuticals, herbicides, and dyestuffs. 

Benzaldehyde has limited uses as a chemical intermediate. It is used as a solvent for oils, resins, cellulose esters, and ethers. It is also used in flavoring compounds and in synthetic perfumes. 

Many aldehydes are particularly fragrant. A number of flowers, for example, owe their pleasant odor to the presence of simple aldehydes. The smells of lemons, cinnamon, and almonds are due to the aldehydes citral, cinnamalde-hyde, and benzaldehyde, respectively. The structures of these three aldehydes are shown in Figure 12.21. The aldehyde vanillin, introduced at the beginning of this chapter, is the key flavoring molecule derived from the vanilla orchid. You may have noticed that vanilla seed pods and vanilla extract are fairly expensive. Imitation vanilla flavoring is less expensive because it is merely a solution of the compound vanillin, which is economically synthesized from the waste chemicals of the wood pulp industry. Imitation vanilla does not taste the same as natural vanilla extract, however, because in addition to vanillin many other flavorful molecules contribute to the complex taste of natural vanilla. Many books made in the days before acid-free paper smell of vanilla because of the vanillin formed and released as the paper ages, a process that is accelerated by the acids the paper contains. 

In most European countries, flavors that occur naturally or are generated during healing or processing by enzymatic reactions or modification generally arc considered natural flavors. Flavors that arc often referred to in the United Stales as synthetic are usually termed "artificial" in Europe. These would include such compounds as ethyl vanillin, allyl-of-iononc, and ethyl maltol. However, substances that are synthesized but chemically identical to the naturally occurring substances arc classified as "natural-identical." This class would include diacetyl, benzaldehyde, antsyl acetate, and benzophenone. 

Benzaldehyde is used as a flavoring material, in the production of cinnamic acid, in the manufacture of malachite green dye, as an ingredient in pharmaceuticals, and as an intermediate in chemical syntheses. 

Aldol and related condensation reactions such as Knoevenagel and Claisen-Schmidt condensations are also widely used in the fine chemicals and specialty chemicals, e.g. flavors and fragrances, industries. Activated hydrotalcites have been employed as solid bases in many of these syntheses. Pertinent examples include the aldol condensation of acetone and citral [107, 108], the first step in the synthesis of ionones, and the Claisen-Schmidt condensation of substituted 2-hydroxyacetophenones with substituted benzaldehydes [109], the synthetic... 

In contrast with the widespread application of zeolites as solid acid catalysts (see earlier), their use as solid base catalysts received scant attention until fairly recently [121]. This is probably because acid-catalyzed processes are much more common in the oil refining and petrochemical industries. Nonetheless, basic zeolites and related mesoporous molecular sieves can catalyze a variety of reactions, such as Knoevenagel condensations and Michael additions, which are key steps in the manufacture of flavors and fragrances, pharmaceuticals and other specialty chemicals [121]. Indeed, the Knoevenagel reaction of benzaldehyde with ethyl cyanoacetate (Fig. 2.36) has become a standard test reaction for solid base catalysts [121]. 

The major advantage of the seunpling technique developed, was that some trace chemicals could be trapped tind described for the first time as Black Truffle aroma constituents. In particular, some compounds, important flavor contributors, generally appearing in small concentrations, such as benzaldehyde, propanal, ethyl acetate, anisole or dimethyl disulfide - previously identified in Shiitake mushrooms (9) - could be characterized. This was also the case for three aromatic compounds, toluene, xylene and ethyl benzene, well known as raw vegetable constituents (1 ). In addition, two aliphatic esters, isopropyl and sec-butyl formates, and one cyclic sulfur compound (2-formyl thiophene) previously reported respectively in plums and apples (W) and in coffee and bread products (n) were identified. 

Bitter Almond Oil There s no need to beat around the bush here, folks. This is the best and most concentrated source on the planet. At 98% cone., Bitter Almond Oil is almost pure benzaldehyde. The oil is plentiful and cheap because benzaldehyde is a major flavoring and fragrance chemical used in many products. Benzaldehyde can also be found in peach and apricot kernel oils. 

Raspberry ketone, a popular flavor and fragrance chemical, used as food additive may be made from p-cre-sol through its oxidation product p-hydroxy benzaldehyde. 

He makes sure that his chemicals, especially the nitroethane, are of a good grade. Nitroethane is widely used in the paint and varnish industry as a solvent for cellulose acetate lacquers, vinyl resins, nitrocellulose, waxes and dyes. If he has the industrial grade, he first distills it before use. Benzaldehyde smells like bitter oil of almonds and should be clear. Benzaldehyde is used in flavorings and perfumes. 

The gas phase partial oxidation of toluene to benzaldehyde is an industriaUy important reaction due to the fact that benzaldehyde is a common intermediate in a wide variety of chemical reaction processes. Almost half of benzaldehyde world production is employed in the synthesis of food additives (mainly flavoring). Although the partial oxidation of aromatic hydrocarbons is widely treated in the literature, the oxidation of toluene to benzaldehyde presents few information, thus requiring systematic studies (1). 

Ethyl vanillin is a closely related compound, 3-ethoxy-4-hydroxy-benzaldehyde, which is not found in nature but is prepared synthetically from safrole. It has an intense vanilla-like odor and is about three to four times more powerful than vanillin as a flavoring agent. Like vanillin, it is widely used in the preparation of imitation vanilla flavorings but can give a somewhat harsh chemical character in higher dosage levels. In practice, a maximum of 10% of vanillin may be replaced by ethyl vanillin without this objectionable note being obvious. 

Vanilla contains vanillin (1.3-3.0%) as the major flavor component, with over 150 other aroma chemicals also present, most of which are present in traces, including p-hydroxy-benzaldehyde, acetic acid, isobutyric acid, caproic acid, eugenol, furfural, p-hydroxy-benzyl methyl ether, vanillyl ethyl ether, anisyl ethyl ether, and acetaldehyde. The vanillin content differs in different varieties of vanilla, with Bourbon beans containing generally higher amounts than Mexican and Tahiti beans (martindale rosengarten stake). 

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