Odor Standards in Squeeze-Bottle Kits for Matching Quality and Intensity

1992 ◽  
Vol 25 (2) ◽  
pp. 1-9 ◽  
Author(s):  
J. E. Amoore

A valuable adjunct to flavor profile analysis, wastewater odor evaluation, and ambient air quality surveying is an array of reference odor standards for side-by-side comparisons with the unknown samples. Sets of convenient, nonspill squeeze-bottle standards have been developed for these purposes. Many of the required odor chemicals are stable in character up to six months in mineral-oil dilution and can provide hundreds of sniff-tests without significant loss of intensity. The author recently proposed a generalized “decismel scale” for describing odor threshold and odor level (by analogy with the decibel scale for sound). Prototype kits are suggested that demonstrate an odor intensity scale and a tentative selection of odor qualities.

1999 ◽  
Vol 40 (6) ◽  
pp. 45-51 ◽  
Author(s):  
Andrea M. Dietrich ◽  
Susan Mirlohi ◽  
Willian F. DaCosta ◽  
Jennifer Peters Dodd ◽  
Richard Sauer ◽  
...  

Reactions of iodine and phenol were investigated to determine which iodophenols were produced and their odor properties. The research was performed in support of the USA space program that applies iodine to disinfect potable water for spacecraft use. Higher concentrations (50 mg/l) and higher iodine:phenol (e.g. 10:1) ratios resulted in the formation of greater iodophenol concentrations and higher substituted iodophenols. The reactions were fast and nearly complete within 1 hour. For pH 5.5 and 8 and all iodine:phenol ratios, formation of monosubstituted compounds indicated that 2-iodophenol was favored over 4-iodophenol. At the intermediate iodine:phenol ratios of 1:1 and 2:1, substantial amounts of the diiophenols formed and persisted for up to 32 days. The diiodophenols were not detected at iodine:phenol ratios of 0.2:1 and 10:1. The compound 2,4,6-triiodophenol was the major product formed at a 10:1 iodine:phenol ratio and the formation of this trisubstituted phenol appeared nearly complete. Odor evaluation indicated that the iodophenols have much lower odor threshold concentrations (OTC) than phenol. The 2- and 4- iodophenol had OTC values of ≅ 1 and 500 μg/l, respectively, with odors described as “medicinal, phenol, chemical”.


2004 ◽  
Vol 49 (9) ◽  
pp. 241-248
Author(s):  
H. Al-Samarrai ◽  
J. Matud ◽  
K. Wiesenthal ◽  
P. Atiyah ◽  
A. Bruchet ◽  
...  

In response to reports of medicinal taste and odor problems in suburban Paris, a lab scale study was conducted to investigate the contribution of different water quality parameters - pH, phenol, bromide, chlorine, temperature and dissolved oxygen levels - on bromophenol medicinal odor formation using the Flavor Profile Analysis (FPA) method. A study of six parameters at 2 levels (64 experiments) analyzed by the FPA method suggests that chlorine at high concentration is more important as a controlling agent than phenol under similar conditions and the ratio of HOBr:Phenol and the time for reaction will control subsequent brominated products of reaction. Results from a three-level statistical model indicate that high pH was associated with lower odor intensities, whereas high levels of chlorine, phenol and temperature were associated with high odor intensities. Potential worst case scenarios of water quality conditions were determined for evaluation by chemical identification and kinetics.


1987 ◽  
Vol 79 (1) ◽  
pp. 26-32 ◽  
Author(s):  
Jeroen H.M. Bartels ◽  
Brian M. Brady ◽  
I.H. Mel Suffet

1995 ◽  
Vol 31 (11) ◽  
pp. 223-228 ◽  
Author(s):  
A. M. Dietrich ◽  
R. C. Hoehn ◽  
L. C. Dufresne ◽  
L. W. Buffin ◽  
D. M. C. Rashash ◽  
...  

The six algal metabolites, at concentrations of 20-225 μg/l, were oxidized with potassium permanganate, chlorine, or chlorine dioxide at doses of 0.25-3 mg/l. Flavor profile analysis (FPA) was used to determine the odors of the solutions before and after oxidation. Linoleic and palmitic acids, which are odorless compounds, were oxidized to odorous products by all three oxidants. The odor intensity of β-cyclocitral (grape, sweet tobacco) and phenethyl alcohol (rose, floral) was only slightly decreased by any of the oxidants. Oxidation by permanganate or chlorine either eliminated or greatly reduced the odors associated with linolenic acid (watermelon) and 2t,6c-nonadienal (cucumber); chlorine dioxide was ineffective at reducing the cucumber odor of 2t,6c-nonadienal. Oxidation, at doses typically applied for drinking water treatment, can result in the destruction of certain algae-related odors but in the formation of other odors.


1999 ◽  
Vol 40 (6) ◽  
pp. 129-133 ◽  
Author(s):  
Djanette Khiari ◽  
Auguste Bruchet ◽  
Thomas Gittelman ◽  
Lleonard Matia ◽  
Sylvia Barrett ◽  
...  

The objectives of this study were to investigate various distribution conditions that directly affect the production of tastes and odors, identify the chemical causes, and develop guidelines to help water utilities solve or prevent these types of problems. This paper presents four case studies of taste-and-odor problems generated in distribution systems. Two types of problems will be presented, (1) problems that occur in association with pipe or reservoir lining material leaching into the water and (2) problems that are caused by a continuation of chemical reactions in the water within the distribution system. The sensory method used was flavor profile analysis (FPA) and the chemical methods were closed loop stripping analysis (CLSA) or liquid-liquid extraction (LLE) coupled with gas chromatography/mass spectrometry (GC/MS). Bromophenols and bromodichloroiodomethanes were found to be the cause of the medicinal odors, while alkyl benzenes and naphthalene were found to be associated with the oil-base paint type of odors.


1988 ◽  
Vol 20 (8-9) ◽  
pp. 31-36 ◽  
Author(s):  
Stuart W. Krasner

Flavor-profile analysis (FPA) is a sensory method utilizing a trained panel of four to six individuals. Reference materials are used to establish a common vocabulary for different odors found in drinking water. Known quantities of different taste- and odor-causing chemicals are evaluated to calibrate the panel on a consistent intensity scale. Each identifiable descriptor is assigned its own intensity. This method has been successfully applied in the analysis of musty-smelling compounds, e.g., 2-methylisoborneol (MIB). MIB samples and standards from 1 to 80 ng/l have been shown to observe the WeberFechner law (i.e., a plot of flavor intensity versus logarithm of concentration of MIB yielded a straight line). FPA has also been used to handle fishy/swampy odor problems. In many instances, specific causative organic compounds were not identified; however, FPA evaluations of water using different free-chlorine dosages and contact times made possible immediate resolution of these odor problems. FPA has yielded reproducible sensory data that have been useful in better understanding and handling off-flavors in drinking water.


1986 ◽  
Vol 78 (3) ◽  
pp. 50-55 ◽  
Author(s):  
Jeroen H.M. Bartels ◽  
Gary A. Burlingame ◽  
I.H. Mel Suffet

1999 ◽  
Vol 40 (6) ◽  
pp. 1-13 ◽  
Author(s):  
I. H. (Mel) Suffet ◽  
Djanette Khiari ◽  
Auguste Bruchet

The “Taste and Odor Wheel” developed over the last 15 years has been updated to include new compounds identified in the eight classes of odorants, four tastes, and one mouth feel/nose feel category. Over the last 10 years, other types of odors have been identified, in addition to chlorinous and ozonous odors of disinfectants, the earthy compound geosmin, and the musty compound 2-methylisoborneol (2-MIB). Sophisticated instrumental analysis, e.g., gas chromatography/mass spectrometry (GC/MS), and sensory analysis, e.g., flavor-profile analysis (FPA), have been successfully combined with sensory GC to identify various odorants.


Sign in / Sign up

Export Citation Format

Share Document