Welcome to PicarroFood Analysis by Cavity Ring-Down Spectroscopy

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Molecules Are In Constant Motion

Symmetricalstretching

Antisymmetricalstretching

Scissoring

Rocking Wagging Twisting

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It’s All Springs and Mirrors

O

H

H

4

Very High Sensitivity and Precision

• Small, 35 cc sample cavity

• Laser intensity builds up…

• …Laser is shut off

• Removes laser fluctuations

• Up to 20 km pathlength

• Light reflects around the cavity

• Cavity loss mechanisms decrease intensity each pass

• Measurement is decay rate not absolute absorbance

Time-basis and long pathlength provide high sensitivity & precision

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Time Based Measurement

Laser

Photo Detector

Pho

to D

etec

tor

Time (s)

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Increase Concentration, Faster Ring-Down

Absorbing species in the cavity follow Beer-Lambert Law

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From Wavelength to Ringdown

Time (micro-seconds)

Det

ecto

r S

igna

l Measure Ring-down

Select Wavelength

Wavelength (nm)

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From Ring-Down to Concentration

Time (micro-seconds)

Det

ecto

r S

igna

l Ringdowns

t

tItI ocirccirc exp)()(

1549.6 1549.8 1550.0 1550.2 1550.4

0.0

1.0x10-6

2.0x10-6

3.0x10-6

4.0x10-6

5.0x10-6

Ab

so

rba

nce

(1

/cm

)

Wavelength (nm)

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Combustion Module

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Extending the Reach of CRDS

iCO2

iH2O

DIC/DOC

DIC

DIC

Automate FX

OI Analytical 1030W

Thermo GasBench II

Costech

EA

Liaison

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Benefits of Cavity Ringdown

• Low capital cost - $50K to $120K.• Low cost of ownership- $100 to $1000/year.• Small Size – as small as 17” x 8” x 23”.• Low power consumption – 100W to 400W• No high vacuum pumps.• Very rugged.• Easy to Use.

12

Food Authenticity

• Fraud is a $50 Billion/yr problem– Wine– Coffee– Olive oil– Milk

• Using costly equipment and scantily adopted methods– IRMS ($350,000)– NMR ($300,000)

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Consumer Rights, Tariffs and Duties

• OJ – where is it from, Florida or Brazil?

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Consumer Safety

• Has cane sugar been added to this honey?• Is this “pure” sesame oil diluted with corn oil?

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Sustainable Plastic Packaging

• $50 Billion/yr by 2014– Adding annually

renewable resources

• Using costly equipment– AMS ($3,000,000)

• Or low tech– LSC (low precision)

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Measuring ‘Green-ness’

• What is the plant content of these bottles and bags?

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Stable Isotopes: Answer These Questions

• Stable isotope data can give simple, unambiguous answers to all these questions and more

• Unique signature from a permanent record of history/source

• Huge potential applications• Can provide simple analysis/screening information• Completely under-exploited to date• New instrumentation is changing that

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Sparkling Water δ13C Analyses

-40.00

-35.00

-30.00

-25.00

-20.00

-15.00

-10.00

-5.00

0.00

• Simple, yet high precision, high reproducibility

δ13C

/per

mil

Fossil fuel based CO2 (Crystal Geyser)

Geothermal based CO2 (Perrier, left and

San Pellegrino)

Artesian well (Fiji)

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Honey Analysis, AOAC 998.12

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

Sample 5 -26.55 -26.19 2.1

Sample 6 -27.80 -27.45 1.9

Data shows that all of the samples tested here are unadulterated using AOAC 998.12 criteria.

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Sample Delta (‰) S.D. (‰) IRMS(‰) Difference (‰)

Honey A -22.22 0.165 -22.2 -0.02

Honey B -21.85 0.120 -22.0 0.15

Honey C -25.22 0.184 -25.6 0.38

Honey D -25.08 0.047 -25.1 0.02

Honey E -27.20 0.082 -26.8 -0.40

Honey F -24.47 0.089 -24.4 -0.07

Honey G -23.77 0.032 -23.9 0.13

Honey H -23.65 0.065 -23.9 0.15

Honey I -23.66 0.046 -23.8 0.14

Honey J -23.74 0.107 -24.2 0.46

Honey Analysis Compared with IRMS

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Food Fraud Detection

Honey adulteration with corn syrup: 5%, 10% & 15%

Exceptional correlation of calculated & measured δ13C values

Δδ values are < 0.1 ‰, even at the 5% adulteration level

R2 = 0.9999

-27-26-25-24-23-22-21-20-19-18-17-16-15-14-13-12-11-10

-27 -26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10

Predicted δ13C value (‰)

Mea

sure

d δ

13C

val

ue

(‰)

100% HFCS

100% Honey

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Orange Juice Origin

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Commercial Apples

• A quick screening method of using stable isotopes to distinguish the true origin and/or composition of natural food and beverage products

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Olive Oil Sample Sources (6 Countries)

Australia

Lebanon

TurkeyGreece

Italy

Spain

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Olive Oil δ13C Analysis: CRDS vs. IRMS

2ul Inj. Vol. CRDS

δ13C (‰)

S.D. (n=3) (‰)

IRMS

δ13C (‰)

Italy -28.98 0.05 -29.27

Australia -31.23 0.01 -31.19

Spain -28.95 0.18 -28.94

Turkey -30.34 0.11 -30.32

Greece -29.29 0.02 -29.21

Lebanon -29.11 0.23 -28.87

(California -30.03 0.19 N/A)

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Conclusion

• Fast, easy tests for food authenticity• Supply chain screening for adulteration• Push button, simple methods for routine lab use