Sensations

Relationship between aroma and flavour simple aromas and flavours can be produced chemically. Synthetic aromas are certainly important and play a major role in a number of industries due to their stability and strength. Despite the availability of synthetic aromas and flavours, many are still extracted from plants as the consumer has a preference for the natural product, and higher prices are paid for the product from natural sources 6 , In recent years the demand for natural products...

Info

Increase in the production of processed foods by industrial methods has resulted in an expanding market for food ingredients such as flavorants and flavor enhancers. In this area recent market surveys have shown that consumers prefer foodstuffs that can be labeled as natural. This preference for natural foods opens the door for bioprocessing because ingredients prepared using fermentation or enzymatic transformation are considered natural. Another factor encouraging development of...

Essential Oils Tenax Xad2

Polystyrene resin for the adsorption of glycoconjugates The detection of glucoconjugated forms of monoterpene alcohols in rose petals more than 25 years ago by Francis and Allcock 1 has opened a new field in flavor research, i.e., the investigation of glycosidically bound aroma compounds. Nowadays, it is well established that flavorless glycosides represent one accumulation form of aroma substances in fruits and in many other plant tissues. Further nonvolatile constituents capable of generating...

Biotechnological Production of Flavour Active Lactones

Haarmann & Reimer GmbH, Postfach 1253, D-37601 Holzminden, Germany 2 Fermentative Production of 2.8 Macrocyclic 3 Enzymatic Synthesis of 3.1 Via Intramolecular 3.2 Via Enantioselective 3.3 Via Baeyer-Villiger Type Biotechnology lends itself to the production of natural flavour materials, which can either be obtained as complex mixtures or pure, individual flavour components. Examples of the latter category are acids, alcohols, esters, aldehydes, ketones and lactones. Biotechnological...

The Production of Aromas by Plant Cell Cultures

Faculty of Applied Biology, University of the West of England, Frenchay, Bristol, BS16 1QY, UK 2 Plant Cell 2.1 Development of Plant Cell or Tissue 3 Potential Aroma Production by Plant Cell 4 Accumulation of Aroma Components in Plant Cell 4.1 Complex Nature of 4.3 Cytotoxicity of Essential 4.5 Transformed 5 Process 5.1 Suspension 5.2 Organised 5.3 Provision of an External Accumulation The adoption of a plant cell or tissue culture process for the production of various aroma compounds will...

Heptanone

Biosynthesis of 2-heptanone from octanoic acid by P. roquefortii, adapted from 143 The need to produce methyl ketones that qualify for the natural label has prompted intensive studies, and several processes involving fatty acids breakdown have been proposed 140, 277-287 , The formation of methyl ketones from fatty acids is described by the following stoichiometric equation R CH2 CH2 COOH + 02 -> R-CO-CH3 + C02 + HzO. This is an aerobic process. The biogenesis of methyl ketones is well...

Opportunities in Microbial Biotransformation of Monoterpenes

Mariet J. van der Werf1, Jan A.M. de Bont1 and David J. Leak2 1 Division of Industrial Microbiology, Department of Food Science, Wageningen Agricultural University, P.O. Box 8129, 6700 EY Wageningen, The Netherlands 2 Department of Biochemistry, Imperial College, London, SW7 2AZ, Great Britain 2 Problems Encountered in Monoterpene Biotransformation Studies 150 2.1 Chemical Instability of Monoterpenes 2.2 Low Solubility of Monoterpenes 2.3 Volatility of 2.4 Toxicity of Monoterpenes 2.5 Absence...

Definitions of Natural Flavours

A special issue that must be addressed as very relevant to bioflavours is the question of definitions of 'natural'. In the USA the Code of Federal Regulations (1990) defines a 'natural' flavour as the essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate of any product of roasting, heating of enzymolysis, which contains the flavouring constituents derived from a spice, fruit juice, vegetable or vegetable juice, edible yeast, herb, bud, bark, root, leaf or similar...

Note Added in Proof

This addition gives details of publications that have only recently come to my attention, also to illustrate further the rapid rate of progress being made in the field of bioflavours by a growing range of expert research groups, and finally to include some papers that I just plain forgot to include. The identification of microbial strains that produce flavour molecules and the elucidation of the enzymatic mechanisms whereby plants produce flavour molecules are both proceeding apace. Christen et...

Vanillin Synthesis

Effective bioprocesses for producing some of the most important flavour molecules have not yet been developed. These include vanillin, which is, organoleptically, the most important component of vanilla. The metabolic pathway that synthesises vanillin in the vanilla bean is still not completely understood. Nevertheless a promising start has been made in developing microbial methods for the production of vanillin. For example eugenol extracted from oil of cloves has been converted into vanillin...

Gamma Decalactone Production

Gamma Decalactone

The synthesis of y-decalactone using intact microorganisms is a particularly good example of the use of biotransformations in the production of flavours because it required the development of truly innovative technology and has made a big commercial impact. The need for a natural source y-decalactone can be illustrated by a chemical analysis of strawberries. At least 350 molecules are thought to contribute to the taste of strawberry, including y-decalactone and over 100 esters. Fig. 10. Flow...