Cavity ring-down spectroscopy (CRDS) provides a sensitive and precise method for stable isotope analysis of food and beverage samples. It can detect adulteration and determine geographic origins through stable isotope signatures. CRDS systems are small, low-cost, easy to use, and provide results comparable to more expensive isotope ratio mass spectrometry (IRMS). Example analyses show CRDS can distinguish between honey samples, detect honey adulterated with corn syrup, and identify the origin of orange juice, olive oil, and sparkling water samples.

1. Welcome to Picarro Food Analysis by Cavity Ring-Down Spectroscopy

2. Molecules Are In Constant Motion Symmetrical stretching Antisymmetrical stretching Scissoring Rocking Wagging Twisting

3. It’s All Springs and Mirrors O H H

5. Time Based Measurement Laser Photo Detector Photo Detector Time (  s)

6. Increase Concentration, Faster Ring-Down Absorbing species in the cavity follow Beer-Lambert Law

7. From Wavelength to Ringdown Time (micro-seconds) Detector Signal Measure Ring-down Select Wavelength Wavelength (nm)

8. From Ring-Down to Concentration Time (micro-seconds) Detector Signal Ringdowns

9. Combustion Module

10. Extending the Reach of CRDS iCO 2 iH 2 O DIC/DOC DIC DIC Automate FX OI Analytical 1030W Thermo GasBench II Costech EA Liaison

19. Honey Analysis, AOAC 998.12 Data shows that all of the samples tested here are unadulterated using AOAC 998.12 criteria. Sample Protein ( ‰ ) Honey ( ‰ ) C4 Sugars ( % ) Sample 1 - 26.57 - 27.35 - 4.6 Sample 2 - 26.79 - 27.57 - 4.6 Sample 3 - 26.27 - 25.45 5.0 Sample 4 - 26.21 - 27.84 - 9.8 Samp le 5 - 26.55 - 26.19 2.1 Sample 6 - 27.80 - 27.45 1.9

20. Honey Analysis Compared with IRMS -24.2 -23.8 -23.9 -23.9 -24.4 -26.8 -25.1 -25.6 -22.0 -22.2 IRMS ( ‰ ) 0.46 0.14 0.15 0.13 -0.07 -0.40 0.02 0.38 0.15 -0.02 Difference ( ‰ ) 0.107 0.046 0.065 0.032 0.089 0.082 0.047 0.184 0.120 0.165 S.D. ( ‰ ) -22.22 Honey A -21.85 Honey B -25.22 Honey C -25.08 Honey D -27.20 Honey E -23.65 Honey H -23.66 Honey I -23.77 Honey G -23.74 Honey J -24.47 Honey F Delta ( ‰ ) Sample

22. Orange Juice Origin

24. Olive Oil Sample Sources (6 Countries) Australia Lebanon Turkey Greece Italy Spain

25. Olive Oil δ 13 C Analysis: CRDS vs. IRMS N/A) 0.19 -30.03 (California -28.87 0.23 -29.11 Lebanon -29.21 0.02 -29.29 Greece -30.32 0.11 -30.34 Turkey -28.94 0.18 -28.95 Spain -31.19 0.01 -31.23 Australia -29.27 0.05 -28.98 Italy IRMS δ 13 C ( ‰) S.D. (n=3) ( ‰) CRDS δ 13 C ( ‰) 2ul Inj. Vol.