Article Figures & Data
Figures
- Figure 1
Apparatus for measuring hydrogen sulfide (H2S) using (A) inert gas (N2) sparging and (B) vacuum aspiration. The sample flask is connected to an impinger, and the gas detection tubes are connected to the outlet, in series.
- Figure 2
Calibration curves for hydrogen sulfide (H2S) (mass of H2S [y, ng] versus stain length [x, mm]) on Gastec 4LT gas detection tubes: Aspiration Method from the current study, regression equation is y = 14.7x; N2 Method from the current study, y = 10.0x; Alka-Seltzer tablet sparging, with regression equation calculated from reported values,17 y = 14.9x. The manufacturer’s theoretical regression equation (H2S versus stain length; y = 10.0x) is calculated from tube markings. For all regressions, the intercept was not significantly different from zero and was omitted.
- Figure 3
In-lab reproducibility of N2 Method measured over four weeks with higher concentration standards (Δ) = 3.10 μg/L (n = 7) and lower concentration standards (●) = 1.55 μg/L ng (n = 9). Sample measurements are normalized to the expected value (% Recovery hydrogen sulfide [H2S] = H2S measured/H2S added). The 95% confidence interval (CI) is shown as μ = 94.4 ± 2.9%.
- Figure 4
Quantitation of free hydrogen sulfide (H2S) in a selection of commercial bottled (n = 6) and canned wines (n = 6).
Tables
Supplemental Figure 1 Color change in Gastec 4LT (A, B), 4LL (C, D), and 5L (E, F) gas detection tubes, showing tubes before (B, D, F) and after (A, C, E) use.
Supplemental Figure 2 The response of the gas detection tube method (mm stain/ng hydrogen sulfide [H2S]) with changing sample volume. Measurements were performed by the N2 Method, and samples are prepared in both model wine and water. The response did not differ significantly (analysis of variance, p > 0.05) as a function of sample volume.
Supplemental Video 1 Analysis of Free Hydrogen Sulfide in Wines Using Gas Detection Tubes
https://www.youtube.com/watch?v=ulLZ75ZOzQ4
Supplemental Calculation
Theoretical mass of hydrogen sulfide (H2S), as determined from 4LT gas detection tube (GDT)
concentration markings (length of color change in mm to ng).
Vol 6 Issue 1
