Synthetic Flavoring Materials

Researchers, using the analytical techniques available, are now able to separate and identify most of the compounds responsible for the aroma of foods [1]. From this vast list of aroma compounds ( 7,000), a more limited subset of compounds, i.e., those that have significant flavoring properties, has been selected for manufacture by synthetic means. To be of any value to the flavorist or flavor manufacturer, a 

The purity of synthetic flavorants is a very important quality attribute. Chemicals are rarely so pure that they have simple odor and flavor profiles. Most contain sufficient trace impurities, stemming either from the starting materials or processing conditions used iu their manufacture, to display a spectrum of perceptible character notes. Sometimes it is the presence of these impurities, which characterize the compound and make it far more acceptable as a flavorant than the pure uiaterial itself  

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Table 5.42. Synthetic Flavoring Materials (not naturally occurring in food)...

K. Bauer and D. Garbe, Common Fragrance and Flavor Materials VCH VedagsgesseUschaft, Weinheim, Germany, 1985. P. Z. Bedoukian, Pefume and Flavoring Synthetics Allured Publishing Corp., Wheaton, lU., 1986. 

However, the lower fatty acid esters (particularly the acetates) of the acyclic terpene alcohols geraniol, linalool, and citronellol are extremely important both as fragrance and as flavor substances. The acetates occur in many essential oils, sometimes in rather high amounts. Formates, propionates, and butyrates occur less frequently. As a result of the development of large-scale production processes for terpenes, the esters of acyclic terpene alcohols are nearly always made synthetically. All acyclic terpene esters that are used as fragrance and flavor materials can be prepared by direct esterification of the appropriate alcohols. However, special precautions are required for the esterification of linalool. 

The industrial flavor producers offer a very broad selection of natural and synthetic flavors,mainly in the form of liquid concentrates.The majority of flavor constituents in such concentrates exhibit considerable sensitivity to air,light irradiation and elevated temperature. These flavor concentrates are moreover oily,greasy rather lipophilic materials,which are difficult to work with. The natural plant extracts also have microbiological contaminations that need to be removed. 

Exercise 26-12 Devise a reasonable sequence of synthetic steps for conversion of eugenol to the flavoring material vanillin, which is 3-methoxy-4-hydroxybenzene-carbaldehyde (Section 26-5). 

The use of polyamide is advantageous because it separates natural from synthetic coloring material, removes sugars, acids, and flavoring materials, and concentrates dilute solutions of colors (156,167). However, the use of polyamide is not applicable to chocolate brown FB, chocolate brown HT, or indigotine, because the two chocolate browns are not completely eluted from the column and indigotine decomposes during extraction (157). 

Ethyl acetate finds particular use as a flavor enhancer in foods and pharmaceuticals because of its fruity taste when diluted. It is included on the US Eood and Drug Administration s Generally Recognized As Safe list for use as a synthetic flavoring agent. Ethyl acetate is also approved for use as an indirect food additive in certain packaging materials. 

Use Chemical intermediate for dyes, flavoring materials, perfumes, and aromatic alcohols solvent for oils, resins, some cellulose ethers, cellulose acetate and nitrate flavoring compounds synthetic perfumes manufacturing of cinnamic acid, benzoic acid pharmaceuticals photographic chemicals. 

Any substance or mixture of substances that contributes apositive taste to a food product, such as vanillin, cacao, and fruit extracts among natural products, together with numerous synthetic compounds that imitate or duplicate these tastes. Undesirable or off flavors occur in milk, meat, and other food products as a result of improper preparation, oxidation, and incipient rancidity. There are over 1500 flavoring materials listed as food additives under provisions of the Food, Drug, and Cosmetics Act. 

I would like to stress that, as far as the functionality in food is concerned, there is no difference between the flavoring materials from natural or synthetic origin. It is up to the marketing policy of the food industry, and the educated choice of the final consumer, which class of flavoring materials will be chosen for a certain application. 

Vanillin and veratraldehyde are two fine examples of flavor and fragrance chemicals which have been successfully synthesized from p-cresol. A number of low volume synthetic perfume materials based on p-cresol esters and ethers have also been introduced. Following are some of the important products. 

Fatty acid esters and amines Ferric ammonium oxalate Flavors and flavoring materials, synthetic... 

Although synthetic flavor and fragrance materials are produced on industrial scales, naturally occurring raw materials continue to be essential, important ingredients in the manufacture of flavor and fragrance compositions for several reasons. First, the compositions and sensory natures of natural products are often too complex to be reproduced by combinations of synthetic fragrance substances. Second, the characteristic flavor and fragrance substances of a particular product often cannot be synthesized at a competitive price. Third, the use of natural materials in the production of certain flavor compositions is compulsory. Moreover, a continous demand for perfumes based on natural materials is still observed. 

The development of the low-tar cigarette required enrichment of smoke flavors in order to make the product acceptable to the consumer. The flavor is enhanced by addition of undescribed materials that may include concentrates of flavor precursors obtained from tobacco, licorice, extracts from other plants, or semisynthetic or fully synthetic flavor components. Because these additives have not been identified, no... 

The citrus fruit peels in general have been used as food with or without processing so far, and also extremely small amount of essential oils of the peels have been utilized as flavors, fragrances, or synthetic starting materials such as pharmaceutical and agricultural chemicals and other chemical products. However, a large parts of them have been wasted even now. Therefore, it is very important to find an efficient way of utilization of citrus fruit peels as one of the valuable organic chemical resources. 

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