Phenols, volatile

Volatile phenols Eugenol Passion fruit Passion fruit juice Passion fruit peel Wines... 

Wengle B, Hellstron K. 1972. Volatile phenols in the serum of uraemic patients. Clin Sci 43 493-498. 

M. J. Hill, A. J. Taylor, M. H. Thompson and R. Wait, Fecal steroids and urinary volatile phenols in four Scandinavian populations, Nutr. Cancer, 1982, 4(1), 67. 

Tehtonen M. 1983. Gas-liquid chromatographic determination of volatile phenols in matured distilled alcoholic beverages. 66(1) 62-70. 

Dugelay, I. et al.. Role of cinnamoyl esterase activities from enzyme preparations on the formation of volatile phenols during winemaking. J. Agric. Food Chem. 41, 2092, 1993. 

Chatonnet, P. et al., Synthesis of volatile phenols by Saccharomyces cerevisiae in wines. J. Sci. Food Agric. 62, 191, 1993. 

Kundel, H. Liblik, V. 2000. Emission of volatile phenols from stabilization ponds of oil shale ash dump leachate. Oil Shale, 17, 81-94. 

Partial least squares regression analysis (PLS) has been used to predict intensity of sweet odour in volatile phenols. This is a relatively new multivariate technique, which has been of particular use in the study of quantitative structure-activity relationships. In recent pharmacological and toxicological studies, PLS has been used to predict activity of molecular structures from a set of physico-chemical molecular descriptors. These techniques will aid understanding of natural flavours and the development of synthetic ones. 

To test the potential of PLS to predict odour quality, it was used in a QSAR study of volatile phenols. A group of trained sensory panelists used descriptive analysis (28) to provide odour profiles for 17 phenols. The vocabulary consisted of 44 descriptive terms, and a scale fiom 0 (absent) to S (very strong) was used. The panel average sensory scores for the term sweet were extracted and used as the Y-block of data, to be predicted from physico-chemical data. 

Figure 2. Scores of 17 volatile phenols on two PLS factors. 1 = eug ol, 2 = iso-eugenol, 3 = 4-meUiyl-guiacol, 4 = 4-ethyl-guiacol, 5 = 4-hydroxy-benzaldehyde, 6 = 2,4-dihydroxy-benzaldehyde, 7 =...

Figure 4. Sweet score predicted by PLS model plotted against measured sensoiy score for volatile phenols, omitting vanillin.

A large number of volatile phenols and related compounds occur in vegetables and fruits, and some of them are potent aroma compounds. The majority of volatile phenols and related compounds in plants are formed mainly through the shikimic acid pathway, and are present in intact plant tissue either as free... 

Volatile phenols 4-ethylphe-nol, 4-vinylphenol, 4-ethyl-guaiacol, 4-vinylguaiacol Strong X X Strong X... 

Ranunculus ternatus Thunb. Mao Zhua Chao (leaf) Tannins, phenolic acids, volatile phenols, nonvolatile terpenic compounds, volatile carbonyl and S-containing compounds.60-223 Treat abscesses. 

Alasalvar C, Grigorr JM, Zhang D. 2001. Comparison of volatiles, phenolic compounds, sugars, antioxidant vitamins and sensory quality of different coloured carrot varieties. J Agric Food Chem 49 1410-1416. 

Jin, H., Yang, X., Yu, H. and Yin, D. (1999) Identification of ammonia and volatile phenols as primary toxicants in a coal gasification effluent, Bulletin of Environmental Contamination and Toxicology 63, 399-406. 

Thymol (isopropyl-m-cresol) is a volatile, phenolic monoterpene produced by several plants including thyme (Thymus vulgaris L.) (Baerheim Svendsen and Scheffer, 1985). Thymol has well-known antiseptic, antifungal, and anthelminthic properties (Wilson et al., 1977) and is also used for food and fragrance applications (Bauer et al., 1990). 

During the aging of CM wines, a sharp increase in volatile phenol content has sometimes been noted (Etievant et ah, 1989). It is likely that this observation is due to an inappropriate handling and the result of contamination by Brettanomyces and various bacteria subsequent to alcoholic fermentation. 

Etievant, P., Issanchou, S., Marie, S., Ducruet, V., and Flanzy, C. (1989). Sensory impact of volatile phenols on red wine aroma Influence of carbonic maceration and time storage. Sci. Aliments 9,19-33. 

Tetradecanoic acid Volatile phenols 60, 73, 55 Very faint, waxy-oily 10,000... 

Perestrelo, R., Barros, A. S., Camara, J. S., and Rocha, S. M. (2011). In-depth search focused on furans, lactones, volatile phenols, and acetals as potential age markers of Madeira wines by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry combined with solid phase microextraction. ]. Agric. Food Chem. 59, 3186-3204. 

As seen with increasing thickness (Table II), the relative stability of Resins A and D increases with decreasing temperatures. Resins B and E increased in relative stability with increasing temperatures. This may indicate that A and D are stabilized with relatively volatile phenolic antioxidants and/or synergists and that B and E contain relatively nonvolatile antioxidants which are only moderately effective. 

Unfortunately, uncontrolled MLF also presents a risk of wine spoilage by compounds that can produce off-flavours (including acetic acid, volatile phenols and mousiness) or that may be hazardous to human health (such as ethyl carbamate and biogenic amines). The most important aspects of the development of LAB and MLF in wines are dealt with in this chapter. 

Several strains of LAB isolated from wine were tested for their abilities to metabolize ferulic and p-coumaric acids. Cavin et al. (1993) showed that these acids were strongly decarboxylated by growing cultures of Lactobacillus brevis, Lactobacillus plantarum, and Pediococcus when decarboxylation was observed, volatile phenols (4-ethylguaiacol and 4-ethylphenol) were detected, indicating the possibility of reduction of the side chain before or after decarboxylation. Couto et al. (2006) reported L. collinoides as a producer of volatile phenols, although strain specificity concerning this capacity was observed. L. mali, L. sake, L. viridescens, and P. acidi-lactici were also found to be able to produce volatile compounds but they only perform the decarboxylation step. Volatile phenols cause animal taints such as horse sweat, wet animal and urine that are usually attributed to Brettanomyces spoilage. 

Couto, J.A., Campos, EM., Eigueiredo, A.R., Hogg, TA. (2006). Ability of lactic acid bacteria to produce volatile phenols. Am. J. Enol. Vitic., 57, 166-171. 

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