Organoleptic effect

Monochlorophenols represent an important class of environmental water pollutants of moderate toxicity to mammalian and aquatic life they possess relatively strong organoleptic effects, with taste thresholds of 0.1 pg/L (ppb). Their principal sources are the natural degradation of chlorinated herbicides (e.g., chlorophenoxyacetic acids), chlorination of phenolic substances in waste effluents, and chlorine treatment of drinking water. Of the three chlo-rophenols examined here, 3-chlorophenol exhibited the greatest resistance to sonolysis. 

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. 

Some of UV-absorbing organic compounds are known for their toxic or organoleptic effects. According to their toxicity, international legislation has established several lists... 

Contamination may arise from chemical interaction, organoleptic effects, exchange of ingredients between product and pack, or from particulates or biological-microbiological causes. Further details of some of these are given below. 

TOXICITY organoleptic effects 100 pg/L goldfish 24 hr LC50 10 ppm amount found in dead fish 10 ppm 200 pg/g fathead minnows (Pimpephales promelas) 96 hr TLm 1.0-0.1 mg/L (static bioassay)... 

The fact that enologists need to distinguish between total acidity, pH and volatile acidity demonstrates the importance of the concept of acidity in wine. This is due to the different organoleptic effects of these three types of acidity. Indeed, in any professional tasting, the total acidity, pH and volatile acidity of the wine samples are always specified, together with the alcohol and residual sugar contents. 

Fig. 8.5. Wines classified according to their volatile phenol concentrations. Organoleptic effect. Percentage of phenol wines with a concentration S above the perception threshold (Chatonnet et ah, 1993b)...

These normal quantities, attribntable to specific winemaking techniques, have no organoleptic effects. However, this substance may also be prodnced accidentally, cansing a bitter almond flavor . This defect corresponds to a benzoic aldehyde content that may be as high as 20 mg/1. This... 

Filtration throngh a coarse diatomaceous earth precoat (2.3 and 1.5 Darcy) did not affect chemical composition. The same operation with fine earth (0.35 Darcy) reduced the polysaccharide and condensed tannin content by 10%. No organoleptic effects were identified when the samples were tasted one month after filtration. 

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