effect of consumer food preparation on acrylamide formation lauren jackson, ph.d. u.s. food and drug...
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Effect of Consumer Food Preparation on Acrylamide
FormationLauren Jackson, Ph.D.U.S. Food and Drug Administration
Center for Food Safety and Applied NutritionNational Center for Food Safety & Technology
Summit-Argo, IL
IAFP Latin America Symposium on Food Safety
Campinas, BrazilMay 27, 2008
National Center for Food Safety and Technology (NCFST)
Unique research consortium composed of scientists from academia, the FDA, and food-related industries Conduct research promoting the safety of the U.S. food supply Conduct research needed to answer regulatory questions
related to food safety
Areas of expertise Microbiology Allergens Chemical Contaminants/Constituents Food Packaging Food Processing Novel Preservation Technologies Non-Traditional Contaminants (CT) Nutrition
Background Neurotoxin and potential human
carcinogen JECFA concluded that acrylamide may
be a human health concern based on Margin of Exposure (MOE)
First report, Sweden, April 2002 Found in a wide range of foods,
including dietary staples• Potato products• Breakfast cereal• Coffee• Bakery products• Snack foods
Formed through traditional cooking methods (temperatures >120ºC)
0.820.011Corn Snacks
0.800.015Soft Bread
0.760.016Chili con Carne
0.590.026Cookies
0.690.018Pies and Cakes
0.730.017Crackers
0.650.023Toast
0.530.028Brewed Coffee
0.470.041B. Cereal
0.380.046Potato Chips
0.270.051French Fries (O)
0.160.070French Fries (R)
Cumulative Percentile
Mean AA intake
(µg/kgbw-day)Food
0.820.011Corn Snacks
0.800.015Soft Bread
0.760.016Chili con Carne
0.590.026Cookies
0.690.018Pies and Cakes
0.730.017Crackers
0.650.023Toast
0.530.028Brewed Coffee
0.470.041B. Cereal
0.380.046Potato Chips
0.270.051French Fries (O)
0.160.070French Fries (R)
Cumulative Percentile
Mean AA intake
(µg/kgbw-day)Food
Top 12 Foods by Mean Acrylamide Intake
Background
Formed from asparagine and reducing sugars via Maillard reaction
Found in industrially processed food, home-prepared food, and in foods prepared in food-service/restaurant operations
Exposure from home-prepared foods- not known• Countries/regions differ in
food choices and cooking methods
• Cultural/ethic factors
Acrylamide Research at NCFST
Acrylamide Content of Home-Prepared Foods
Objectives: Measure the acrylamide content of
home-prepared/finished foods Examine the effects of cooking
conditions on acrylamide formation Assess the role of ingredient variation
on acrylamide content Evaluate in-home acrylamide
mitigation strategies
Mitigation Possibilities:
AgronomicalProcessing/cooking
Cooking conditions Control of surface browning Pretreatments Fermentation
Recipe/food compositionFinal preparation/storage
Agronomical Factors
Reducing sugars are important determinant of acrylamide formation in potato products; Asn important for cereal products
Use cultivars of potatoes that have low levels of reducing sugars
Control storage of raw materials (esp. potatoes)
From Amrein et al. (2003)
Klondike Rose
y = 0.0745x + 198.61
R2 = 0.9215
0
200
400
600
800
1000
1200
1400
0 2500 5000 7500 10000 12500 15000 17500
glucose + fructose (mg/kg)
mic
rog
ram
s
ac
ryla
mid
e/k
g
Potato Storage Conditions Two cultivars of potatoes
• Russet• Klondike Rose
Storage Conditions• Room temperature (22-
26oC)• Refrigerated storage (6-
8oC)• 0 to 4 weeks
Prepared French fries from stored potatoes• 180oC, 3 min• Corn oil
Acrylamide levels greatest in French fries made from refrigerated potatoes
Klondike Rose
0200400600800
100012001400
Day 0 Day 1 Day 7 Day14
Day21
Day28
Room Temperature (22-26 C)Refrigerated Storage (6-8 C)
mic
rog
ram
s a
cry
lam
ide/k
g
Potato Products- Effects of Cooking Conditions
Examined effects frying, baking or broiling conditions (time and/or temperature) on acrylamide formation
Used cooking conditions suggested by manufacturer of French fry product
Examined the effects of oil type and age on acrylamide formation in deep fried French fries
Effects of Frying Conditions on Acrylamide Formation
Acrylamide levels increased with frying time and temperature.
At higher frying temperatures, acrylamide levels increased rapidly at the end of the frying run
Better control of cooking process if fry at lower temperatures/longer times
Oil type and age had no effect on acrylamide levels
0
500
1000
1500
2000
2500
0 2 4 6 8 10
Frying time (min)
150
160
170
180
185
190
mic
rog
ram
s a
cry
lam
ide/k
g
639700 662 658 625 627 596
0100200300400500600700800900
Canola Oil Corn Oil Peanut Oil Crisco Oil SafflowerOil
Olive Oil Virgin OliveOil
Oil type
µg
acr
ylam
ide/
kg
Baked at 232ºC for 16-24 min
Broiled at 260ºC for 10-26 min
AA Levels increased with cooking time
Surface temperatures reached >175ºC in baked French fries
Levels of AA in baked or broiled French fries < AA levels in deep fried French fries
Surface Temperature of Baked French Fries
198 216346
517
725
0
100
200
300
400
500
600
700
800
900
1000
16 18 20 22 24
Baking Time (minutes)
Ac
ryla
mid
e c
on
ce
ntr
ati
on
(m
icro
gra
ms
/kg
)
Std. Dev.
Acrylamide
Effects of Baking/Broiling Time on Acrylamide Formation
Effect of Microwaving vs. Baking
Baked vs. microwaved whole potatoes
Russet and Yukon Gold potatoes
Baked/microwaved potatoes until internal temperature reached ~100ºC
Measured acrylamide levels in potatoes by LC-MS
Potato Cooking Method
Acrylamide content
Yukon Gold
Oven bake 22 ± 5
Yukon Gold
Microwave n.d.
Russet Oven bake 68 ± 23
Russet Microwave n.d.
Acrylamide Formation in Baked Goods
66 µg/kg 54 µg/kg
76 µg/kg140 µg/kg
178 µg/kg
99 µg/kg 134 µg/kg
193 µg/kg 232 µg/kg
301 µg/kg
Peanut Butter Cookies
Chocolate Chip Cookies
Most acrylamide found in crust
Acrylamide levels increases with baking time and temperature
Control of acrylamide- reduce surface browning
Fermentation vs chemical leavening
CONTROL OF SURFACE BROWNING
POTATO PRODUCTS Acrylamide levels
increased with degree of browning
Brown color as measured by “L” and “a” values correlated highly with acrylamide levels
Same acrylamide levels found in French fries with similar degree of browning (fried French fries)
45 µg/kg 76 µg/kg 262 µg/kg
516 µg/kg 866 µg/kg 1512 µg/kg
R2 = 0.8551
10
100
1000
10000
45 55 65 75
"L" value
mic
rog
ram
s ac
ryla
mid
e/kg
F
ren
ch f
ries R2 = 0.8558
10
100
1000
10000
5 10 15 20
"a" value
mic
rog
ram
s a
cry
lam
ide
/kg
F
ren
ch
fri
es
Degree of Surface Browning and Acrylamide Levels in Toasted Bread
POTATO BREAD
210 µg/kg 220 µg/kg 360 µg/kg 610 µg/kg
Effect of Degree of Toasting on Acrylamide Levels
0
100
200
300
400
500
600
700
Untoasted Light Medium Dark
Degree of doneness
Mic
rogr
ams
acry
lam
ide/
kg
brea
d (w
et w
eigh
t)
Wonder WhiteButternut WhiteBrownberry WheatSara Lee WheatHomepride PotatoBrownberry PotatoBeefsteak RyeRosens RyeNature's Cupboard 15 grainThomas' English Muffin
Scraping Toast to Removed Browned Surface
91
483
1972
181
0
500
1000
1500
2000
2500
Untoasted Dark Toasted ToastScrapings
Toast withoutScrapings
Mic
rog
ram
s ac
ryla
mid
e/kg
Processing Pretreatments:Washing/Blanching
0200
400600
8001000
12001400
16001800
Contro
l (no
ne)
Wat
er ri
nse
15 m
in w
ater
soak
30 m
in w
ater
soak
Salt w
ater
rins
e
15 m
in s
alt w
ater
soak
30 m
in s
alt w
ater
soak
vin
egar
rinse
15 m
in v
ineg
ar s
oak
30 m
in v
ineg
ar s
oak
15 m
in v
ineg
ar s
oak +
wat
er ri
nse
15 m
in le
mon
juic
e so
ak
Treatment
mic
rog
ram
s a
cry
lam
ide
/kg
Standard Deviation
Acrylamide level (micrograms/kg)
A
BBC
BC BCBC
CDBC
BCD
BC BC
Effect of Frying to Same Surface Color
Russet potato slices Treatments
• Control• Soaked in water for 15 min
Fried in 180oC corn oil• Control- 4 min• Soaked- 5 min, 20 sec
Fried to same surface color- matched “L” value with Hunter Colorimeter
0
100
200
300
400
500
600
700
800
900
1000
Mic
rogr
ams
acry
lam
ide/
kg
Treatment
Control
Soaked in water
RECIPE/FOOD COMPOSITION
Choice of leavening agent (sodium vs. ammonium bicarbonate)
Sugar source pH Addition of amino
acids/proteins Asparaginase
Conclusions Mitigation possibilities are product dependent. Acrylamide level and degree of browning
increases with cooking/processing times and temperatures.
Degree of browning is a good indicator of acrylamide formation during cooking or processing in most foods.
Proper storage of potatoes before frying is essential for reducing acrylamide levels.
Acrylamide levels in fried and baked foods (potato- and cereal-based) can be minimized if cooked to golden or light brown in color.
Washing treatments are effective at reducing acrylamide levels in potato products, but only if products are subsequently cooked to golden or light brown color.
Removing darkened portions (scraping) of toast is effective at reducing acrylamide levels
Sources of Information on Ways to Reduce Acrylamide Formation/Exposure
Consumer FDA:
Additional Information on Acrylamide, Diet, and Food Storage and Preparation http://www.cfsan.fda.gov/~dms/acryladv.html
JIFSAN Acrylamide Infonet http://www.acrylamide-food.org/ Health Canada:
Acrylamide- What you can do to reduce exposure http://www.hc-sc.gc.ca/ahc-asc/media/nr-cp/2005/2005_stmt-dec_acrylamide2_e.html
HEATOX: http://www.slv.se/templates/SLV_NewsPage.aspx?id=20723&epslanguage=EN-GB
Industry CIAA Toolbox
http://www.ciaa.be/documents/brochures/CIAA_Acrylamide_Toolbox_Oct2006.pdf Codex Committee on Food Additives and Contaminants (CCFAC): Draft Code of
Practice for Reduction of Acrylamide in Foodhttp://www.hc-sc.gc.ca/fn-an/alt_formats/hpfb-dgpsa/pdf/intactivit/cf02_08_e.pdf
HEATOX: http://www.slv.se/upload/heatox/documents/D62_final_project_leaflet_.pdf NORDACRYL:
http://www.matforsk.no/web/sampro.nsf/70455f22829e31ddc1256e47002be222/3f253eeaa596fb9ac125730500301d20?OpenDocument