Detection and Occurrence of Acrylamide in U.S. Foods

Steven M. Musser, Ph.D.

Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration

College Park, Maryland

Topics

• Development and performance of an LC/MS/MS method for the quantitation of acrylamide in a wide variety of foods

• Results of exploratory survey data from U.S. foods

Current Available Methods

MethodLimit of Quantitation

Specificity Percent CV

GC/MS

(Underivatized)10 ppb High 10

GC/MS

(derivatized)50 ppb High 5-10

LC/MS 20 ppb Medium 5-10

LC/MS/MS 10 ppb High 5-10

Method Highlights

• Sample preparation– Sample size– Stable isotope labeled internal standard– Extraction with water– Two step solid phase extraction

• Chromatography– Temperature controlled– Many columns tested, 3 found acceptable

• Detection– Electrospray– Liquid Chromatography/Mass Spectrometry/Mass

Spectrometry (LC/MS/MS)

Sample Preparation• Sample size used for extraction

– 1 gram sub-sample

Bread Crumbs (4) 63 ppb 1.5% RSDCereal (4) 217 ppb 1.2% RSD

Coffee (4) 127 ppb 3.9% RSDPotato Chips (4) 613 ppb 2.7% RSD

– 4 gram sub-sample

Bread Crumbs (3) 65 ppb 2.6% RSDCereal (3) 214 ppb 5.2% RSD

Coffee (3) 115 ppb 0.9% RSDPotato Chips (3) 597 ppb 4.8% RSD

Sample Preparation

OASIS SPE only

With 2nd SPE step

Chromatography

Phenomenex Hydro-RP

YMC ODS H-80

Phenomenex Aqua C18

Quality Control

• Recovery of internal standard

• Duplicate analyses of samples

• Reanalysis of randomly selected samples

• Performance of standards

• Signal/noise and ion abundance ratios

Method Performance• Linearity

– 8 ppb to 3200 ppb– Response factor 0.98, s.d. 0.05% and RSD 4.6%

• Recovery

– 94.8% ± 5.6%

• Precision

Bread Crumbs (4) 63 ppb 0.9 1.5% RSDCereal (4) 217 ppb 2.6 1.2% RSDCoffee (4) 127 ppb 4.9 3.9% RSDPotato Chips (4) 613 ppb 16.7 2.7% RSD

Proficiency Testing

• National Food Processors Association

– 5 Labs with LC/MS/MS– Crackers - 137 ppb mean =148 ppb, s.d.= 8.4– Chips - 224 ppb mean = 225 ppb, s.d. = 13.4

• Food Analysis Performance Assessment Scheme (FAPAS)

– Crispbread– 37 participants, 32 satisfactory scores– 22 (8) labs used LC/MS methods, 19 labs used GC/MS methods– Assigned value 1213 µg/kg– CFSAN reported value 1264 ug/kg

Additional Method Research Needs

• Preparation of final report for single lab method validation

• Preparation of proficiency test materials

• Three lab peer verification of the method

• Full multi-lab study

• Inexpensive, accurate screening method

• Survey foods in U.S.

Exploratory Survey of Acrylamide Levels in U.S. Foods

• How foods were chosen– Previously reported– Recent unpublished findings– Consumption by group or total

• Sampling is not representative

• Many foods have one sample

Food Survey Progress

• About 300 different food samples analyzed

• Nearly 700 analyses

• More than 35 different food types

– Baby foods Nuts

– Breads Seasonings

– Coffee Vegetables

– Meats

Foods with Little or No Acrylamide (LOQ 10 ppb)

Baby food (fruit, cereal)

CaramelChicken (raw, cooked)Creamers, nondairyFish (raw, cooked)GelatinGravyInfant Formula

Marshmallows\Milk (condensed)Potatoes (uncooked)Soy SauceFrozen vegetablesVegetable protein

Examples of Variability within

Selected Food Groups

ppb Acrylamide

0 200 400 600 800 1000 1200 1400

Fo

od

Typ

es

Crackers

Cookies

Coffee

Cocoa

Chips

Chicken

Cereal

Bread

Baby Food

Almonds

Examples of Variability within Selected Food Groups

ppb Acrylamide

0 200 400 600 800 1000 1200 1400

Foo

d T

ype

Veg. canned

Soy Protein

Soup, Dried

Pretzels

Popcorn (Mw)

Peanut Butter

Fries (FF)

Fries (B)

Fish

ppb Acrylamide

0 200 400 600 800 1000 1200

-

Wendys

Popeyes

McDonalds

KFC

Fuddruckers

Burger King

Data from Restaurant Prepared French Fries

Variability in Potato Chips

ppb Acrylamide

200 250 300 350 400 450 500 550 600

Da

te C

od

e

5-Nov

12-Nov

19-Nov

26-Nov

3-Dec

10-Dec

Consumer Food Preparation

of Frozen French Fries

ppb Acrylamide

0 200 400 600 800 1000 1200 1400

-

Frozen

Baked

Consumer Preferences: Baked French Fries

ppb Acylamide

0 200 400 600 800 1000 1200

-

Instructions

Color

This is one example of the effect of personal preference. We should note for clarification that the levels of acrylamide shown here are on the low end of our observed range for frozen fries baked according to instructions (119 -1325 ppb, 12 products).

Consumer Food Preparation

(4885 ppb)(1326 ppb)

(11 ppb)( 0 ppb)

Concluding Remarks

The analytical method is reliable, and results are directly comparable to data from many other laboratories

There is considerable variability in acrylamide levels both in commercially produced and consumer

produced foods

A number of factors contribute to the variability and small sample numbers could be misleading

The amount of variability observed in certain food types suggests it may be possible to reduce acrylamide levels