Taste enhancers, examples

Salty taste enhancing preparations or compounds besides KCl were described. For example, a mixture of certain amino acids based on L-lysine were used to increase the saltiness of a NaCl-reduced preparation [34] y-aminobutyric acid (4) was also used as a salty taste enhancer [35]. Some dipeptides such as N-l-ornithyl taurine hydrochloride or N-L-lysinyl taurine hydrochloride were described as very salty with a clean salt taste [36]. Additionally, choline chloride was suggested as a salt enhancer [37]. 

In some oases, duplex emulsions are important. These are emulsions in emulsions. One can have water droplets in an oil phase, of which larger droplets have been made in a second aqueous phase this is called a water-in-oil-in-water duplex emulsion (W/O/W). Of course, one can also have the reverse (O/W/O emulsion). W/O/W are used in some medical applications (encapsulation of drugs), and in foods, to enhance the perception of fat, for example, but also to mask taste, for example, the taste of bitter peptides. One can also imagine that an O/W emulsion in which the oil phase is for the most part replaced by water droplets inside the oil phase, would combine some of the properties of a concentrated O/W emulsion with a much lower actual oil content of the product, with obvious advantages in terms of health. 

Flavour enhancers and suppressers are used in low concentrations to enhance or suppress other flavours. Examples include maltol and ethylmaltol, which have a low caramel taste and enhance the sugary feeling of products furaneol, which is used with red fruits or wild fruit flavours and vanillin, which softens bitter chocolate and fruit flavours and can also enhance the perception of sweetness. In general, sucrose suppresses bitter, sour and salty tastes, for example in chocolate, and enhances fruit flavours. A further important point for ice cream is that the perception of flavour is affected by temperature flavours are less intense at low temperatures. For this reason, ice cream and water ices are generally more strongly flavoured than products consumed at warmer temperatures, such as soft drinks (Experiment 17 in Chapter 8 demonstrates this). 

Although food acceptance in humans is determined mainly by appearance and texture, flavor is nevertheless also important. For example, spices are added to food not for their nutritional value, but for their taste and flavor. Furthermore, aromas that develop during frying and baking enhance the enjoyment of food. 

Indeed, some wine makers and experimenters have introduced changes to the usual CM scheme to enhance its aging potential. For example, in a blind tasting (Flanzy, 1998), wine from Chateauneuf-du-Pape were still considered in excellent condition after 20 years. 

In Japan, koku or kokumi refers to the delicious taste of food. In particular, it is used when the flavor cannot be represented by any of the five basic taste qualities. It has been reported that kokumi can be classified more concretely into thickness, continuity, mouthfullness of flavor, and harmony of taste.238 Previously, there have been many reports on the constituents or fractions that enhance the flavor relevant to kokumi. In this section, examples of the constituents that provide kokumi are described by illustrating their structures. 

Modifications of user properties have various origins. First, the process of size reduction itself may change the shape of the particles. Some properties, like taste, are sometimes directly induced by the particle size at the bio-sensor s scale. For example, it is now widely known that the gustative quality of chocolate is related to particle size. Another direct consequence of size reduction is an increase of the external specific surface area, that is widely used to enhance the rate of transport phenomena, for example in the case of dissolutions or in fluid/solid extractions. For a given particle size distribution, powder properties may be a consequence of the particles shape. 

Complexation is one of several ways to favorably enhance the physicochemical properties of pharmaceutical compounds. It may loosely be defined as the reversible association of a substrate and ligand to form a new species. Although the classification of complexes is somewhat arbitrary, the differentiation is usually based on the types of interactions and species involved, e.g., metal complexes, molecular complexes, inclusion complexes, and ion-exchange compounds. Cyclodextrins (CDs) are classic examples of compounds that form inclusion complexes. These complexes are formed when a guest molecule is partially or fully included inside a host molecule e.g., CD with no covalent bonding. When inclusion complexes are formed, the physicochemical parameters of the guest molecule are disguised or altered and improvements in the molecule s solubility, stability, taste, safety, bioavailability, etc., are commonly seen. 

Flavor enhancers are used imiversally in the food and pharmaceutical industries. Sugar, carboxylic acids (e.g., citric, malic, and tartaric), common salt (NaCl), amino acids, some amino acid derivatives (e.g., monosodium glutamate—MSG), and spices (e.g., peppers) are most often employed. Although extremely effective with proteins and vegetables, MSG has limited use in pharmaceuticals because it is not a sweetener. Citric acid is most frequently used to enhance taste performance of both liquid and solid pharmaceutical products, as well as a variety of foods. Other acidic agents, such as malic and tartaric acids, are also used for flavor enhancement. In oral liquids, these acids contribute unique and complex organoleptic effects, increasing overall flavor quality. Common salt provides similar effects at its taste threshold level in liquid pharmaceuticals. Vanilla, for example, has a delicate bland flavor, which is effectively enhanced by salt. 

Taste compounds and flavour enhancers are raw materials used in process flavourings and can also be added to the final product. Current examples are sodium and potassium salts, organic acids, monosodium glutamate (MSG) and the 5 -nucleotides 5 -inosine monophosphate (IMP) and 5 -guanosin monophosphate (GMP). 

The contribution of the d enantiomers to the characteristic taste of foods is currently being evaluated, but it is clear that the d enantiomers generally taste sweeter , or at least less bitter , than do their l isomers. Of course, kitchen preparation can involve many subtle chemical changes that enhance the attractiveness of natural foodstuffs, including racemisation (Man and Bada, 1987) therefore d enantiomers may be introduced in this way. Peptides are taste contributors, for example the bitter-tasting dipeptides Trp—Phe and Trp—Pro and the tripeptide Leu—Pro—Trp that are formed in beer yeast residues (Matsusita and Ozaki, 1993). 

The vast majority of salt forms are developed to enhance the aqueous solubihty of drug substances. In some cases, a salt may be preferred with reduced solubihty for use in suspension formulations where solubihty as low as possible is optimum to prevent Ostwald ripening, for taste masking or to prepare a sustained release product. Chlorpromazine is marketed as a tablet and syrup using the hydrochloride salt but the insoluble embonate salt is used in suspension formulations to extend the duration of achon and minimize taste problems. Occasionahy the selection of a salt with only modest aqueous solubihty may be more suitable for use in tablet products prepared by wet granulation. For example, prochlorperazine maleate is used in Stemehl tablets rather than the highly soluble mesylate salt. 

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