VANILLIN PRODUCTION applications

Uses. The main application of vanillin is the flavoring of foods (e.g., ice cream, chocolate, bakery products, and confectioneries). Small quantities are used in perfumery to round and fix sweet, balsamic fragrances. Vanillin is also used as a brightener in galvanotechnical processes and is an important intermediate in, for example, the production of pharmaceuticals such as L-3,4-dihydroxyphenylalanine (l-DOPA) and methyldopa. 

Solubility. Solubility in water is less than 2% the solubility in ethanol is given by the ratio one part vanillin to two parts alcohol. Certain manufacturing processes require that the product be in liquid form. Depending on the application, the solvent must be chosen in accordance with the manufacturing process and regulation requirements. 

Pharmaceutical Products. Rlic ne-Poulenc offers a flaked technical-grade vanillin, Vaniltek, to be used in pharmaceutical applications. The single largest use for vanillin is as a starting material for the manufacture of an antihypertensive drug having the chemical name of Methyldopa or L-3-(3,4-dihydroxyphenyl)-2-methylalanine. 

The oxidising properties of ozone have led to the application of this gas to the bleaching of such substances as starch, flour, oils, and wax, delicate fabrics, etc. It has been used in the production of artificial silk and synthetic camphor. It has also been used to aid the ageing or maturing of wines, spirits, and tobacco. The action of ozone on unsaturated organic compounds provides a very convenient general method for the preparation of aldehydes and ketones, which has already been applied to the manufacture of vanillin for flavouring purposes and heliotropin for perfumery. 

Pavolini (118) who prepared curcumin by condensation of acetylacetone with vanilline. He observed that Knoevenagel condensation, one of the main side reactions, could be suppressed by adding boric oxide. This method was further developed by Pabon (119) who first prepared a complex from acetylacetone and boric anhydride and reacted the product with vanilline in the presence of triisopropyl borate and butylamine. Yields calculated on vanilline were thus improved from 10% to 80%. Besides several other indutrial applications (120-123) the method was also used for the synthesis of dihydroyashabushiketol (6) (11) and the tetramethylether of oregonin (11) (14). By selective alkylation of acetylacetone at C-3 Pedersen and associates exploited the above method for the preparation of a series of non-natural diaiylheptanoids substituted at C-4 (124). 

Catechol is also employed for the industrial antioxidant 4-tert-butylcatechol, and its monomethyl ether, guaiacol is used for the production of vanillin (10). This account is by no means a complete summary of the applications of the dihydric phenols more of which have been listed elsewhere (ref. 38). 

Copper-catalyzed aerobic alcohol oxidation has proven to be a key step in the production of vanillin, but other commercial-scale applications have not yet been realized. Nevertheless, the industrial interest in some of the early cop-per/cocatalyst systems for aerobic oxidation bodes well for future apphcations. Recent academic studies have led to significantly improved catalyst systems... 

In this experimental section, the production of polysulfone microcapsules containing vanillin is described. Our method is based on the phase inversion by immersion precipitation technique. The herein described process has been successfully employed for the encapsulation of vanillin into polysulfone microcapsules and, in addition, vanillin release from those capsules has been characterized. Polysulfone/vanillin microcapsules could have an application in laundry industry and also in medical applications. ... 

The determination of the isotopic composition of the carbon in organic compounds has become a useful tool in differentiating between natural and synthetic products. Both the determination of the stable isotopic ratio of and and the determination of the 0 have been sucessfully applied to a variety of products to determine sophistication (10, 11). Since the application of GC isolation and stable isotope ratio analysis was successful in the detection of vanilla/vanillin sophistication (4), it was decided to apply the same methodology to cinnamon/cinnamic aldehyde. As can be seen from Table 1, this procedure could not differentiate between natural and synthetic cinnamic aldehyde the natural compound apparently is biosynthesized via the Calvin cycle, and synthetic... 

Oxidation, which is normally done for the production of vanillin. After vanillin recovery, the remaining low sugar, partially desulphonated, oxidized lignosulphonate is recovered and used in specific applications. 

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