VANILLIN PRODUCTION extracting

Preparation from Waste Sulfite Liquors. The starting material for vanillin production can also be the lignin (qv) present in sulfite wastes from the ceUulose industry. The concentrated mother Hquors are treated with alkaH at elevated temperature and pressure in the presence of oxidants. The vanillin formed is separated from the by-products, particularly acetovanillone, 4-hydroxy-3-methoxyacetophenone, by extraction, distillation, and crystallization. 

Aryl-aldehyde dehydrogenase was purified from Neurospora crassa to remove a dehydrogenase that reduces vanillin to vanillyl alcohol 23). Vanillic acid, isovanillic acid, and PCA were extracted from a fermentation broth with ethyl acetate. Reprecipitation of the isolated products increased the vanillic acid PCA ratio from 1 2 to 2.5 1 (mol/mol). Incubation of the resulting mixture with aryl aldehyde dehydrogenase, NADP, and ATP for 7 h at 30 C resulted in a 92% reduction of vanillic acid to vanillin but only a 33% reduction of PCA to protocatechualdehyde. Vanillin was extracted from the reaction with CH2CI2, affording a product with 10 mol % isovanillin as the only detected contaminant. Based on the concentration of vanillic acid in the fermentation broth, reduction of vanillic acid through purification of vanillin proceeded in 66% overall yield. 

To recover vanillin by the Howard Smith method from waste sulfite lye, the lye is mixed in a pressure reactor with equal amounts of nitrobenzene (oxidizing agent) and sodium hydroxide (Figure 3.61). The mixture is then heated to 200 °C and boiled for 1 to 2 hours. After depressurizing, the reaction product is sprung with CO2. In general, only a small quantity of sulfuric acid is added for full acidification. The liberated vanillin is extracted from the mixture in an extractor with benzene or butanol afterwards the solvent is distilled off. 

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is the most important flavor ingredient available on the market. Natural vanillin is extracted from the beans, or pods, of the orchid Vanilla planifolia, V. tahitiensis, and V fragrans, mainly cultivated in Madagascar, Mexico, Tahiti, and Indonesia. Natural vanilla flavor supplies cover 1% of the demand the remainder is synthesized cheaply by chemical routes. Vanillin is employed not only in the F F industry, but it is also a key intermediate in the production of chemicals and pharmaceuticals (e.g., drugs, herbicides, antimicrobial agents, antifoaming agents) [31]. 

The food flavor industry is the largest user of vanillin, an indispensable ingredient in chocolate, candy, bakery products, and ice cream. Commercial vanilla extracts are made by macerating one part of vanilla beans with ten parts of 40—50% alcohol. Although vanillin is the primary active ingredient of vanilla beans, the full flavor of vanilla extract is the result of the presence of not only vanillin but also other ingredients, especially Httle-known resinous materials which contribute greatly to the quaUty of the flavor. 

The known hazardous effects of most synthetic corrosion inhibitors are the reasons for the search of safer and environmentally friendly natural products. Plant extracts are viewed as an incredibly rich source of naturally synthesized chemical compounds that can be extracted at low costs. Naturally occurring substances such as vanillin [1], Opuntia extracts [2], lawsonia extract [3], natural honey [4] and extracts of chamomile, halfabar, black cumin and kidney bean [5] are some... 

Validation of the role of femloyl-CoA in the synthesis of the vanillin precursor will be detection of the appropriate intermediates and/or enzyme activities in placental extracts that could account for the production of the predicted levels of capsaicinoids. The presence of low levels of monolignol intermediates could be explained by lignin biosynthesis. An alternate route from phenylalanine to vanillin has been considered by some investigators Orlova et al. [68] demonstrated the role of the benzenoid pathway in petunia flowers for the biosynthesis of phenylpropanoid/benzenoid volatiles. 

Vanillylamine [(4-hydroxy-3-methoxy-phenyl)methylamine] is the substrate of choice for the formation of vanillin with the help of amine oxidase. It can be obtained by cleavage of capsaicin (N-[(4-hydroxy-3-methoxy-phenyl)methyl]-8-methyl-6-nonenamide) isolated from pepper and capsicum [83]. As natural vanillin extracted from beans of Vanilla planifolia is rare and extremely expensive, this pathway for the production of natural vanillin is regarded to have a great potential. The vanillin obtained by the process can be labelled as natural if the cleavage of capsaicin is performed enzymatically. 

Vanillin, syringaldehyde, and related phenolic products derived from lignin appear to be important in the desirable odor contributed to beverages by oak barrels (25, 26, 27). These substances are present in the wood, but more appears in the beverage than simple extraction seems to allow. Also the odor of vanillin seems to increase with time and mellowing of the beverage compared with a fresh extract of new wood (25). 

Sometimes there are problems in using CO2 extracts in the usual formulation because of the high concentration of vanillin. The concentration is up to 100 times higher than in alcohol extracts, where it is only 0.2%. Under certain conditions, crystalline vanillin is separated from the water phase of the extract. After drying this crystalline phase, a product with more than 90% vanillin can be produced. By mixing these vanillin crystals back with the oil-phase any desired vanillin concentration can be obtained, which makes the product very useful for the food industry. 

VANILLIN. Vanillin, [CAS 121-35-5]. CgHgCL, a natural product, can be found as a glucoside (ghicovanillin) in vanilla beans, at concentrations of about 2%. It can be extracted with water, alcohol, or other organic solvents. Approximately 250 by-products have been identified m natural vanilla, out of which 26 are present at levels in excess of 1 ppm. The balance of all these products contributes to the subtle taste of vanilla beans, The vanilla bean contains about 2% vanillin, but the 10% extract prepared from beans has several times lire strength of a solution of 2% vanillin. The best known natural source of vanillin is the vanilla plant, Vanilla planifolia A., which belongs to the orchid family. It is cultivated mainly in Mexico, Madagascar, Reunion, Java, and Tahiti. 

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