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Submitted by: Divya ChhabraM.tech(FPT)
01316014913
Acrylamide is the acrylic amide or an amide
group linked to the acryloyl group.
• IUPAC: Prop-2-enamide
• Raw formula: C3H5NO3
• Melting point: 84.5 °C
• Boiling point :136°C
• EU classification:
Toxic (T)
Carcinogen Cat. 2
Mutagenic Cat. 2
• Unsaturated and highly reactive amide
• White odourless crystalline solid
• Soluble in water, ethanol, ether and chloroform
• Synthesized for the first time in 1949.
• In 1950 industrial chemical used for water treatment, paper industry, glues, flocculants, synthesis of dyes and gels.
• In 2002 Swedish researchers announced the discovery of Acrylamide in food.
• In 2009 Health Canada assesses whether acrylamide is a hazard to human health and whether any regulatory action needs to be taken.
• In 2010 EChA added acrylamide to the list of substances of very high concern.
ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation, through the skin and by ingestion.
INHALATION RISK: Evaporation at 20°C is negligible; a harmful concentration of airborne particles can, however, be reached quickly.
EFFECTS OF SHORT-TERM EXPOSURE: irritating the eyes, the skin and the respiratory tract. The substance may cause effects on the central nervous system.
EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: effects on the nervous system, resulting in peripheral nerve damage. This substance is probably carcinogenic to humans. May cause heritable genetic damage in humans.
Reaction between the reducing sugars and Asparagine in the context of the Maillard Reaction (browning) and through triglycerides.
Thermal input (temperature & heating time) frying, roasting or baking generally at + 120°C for more than 20 mins and water activity of 0.4 and below.
Top Eight Foods: French fries (oil fried and oven baked),breakfast cereals, potato chips, cookies, coffee, toastedbread and baby foods.
Mechanism of formation from Maillard reactn
graph
380 400 420 440
Temperature (Kelvin)
05
00
010000
15000
20000
Acry
lam
ide (
ppb)
AA = 442.3 * e(0.07930*(Temp-383))
Potato chipsFrying time: 15 minutes
0
5000
10000
15000
20000
25000
30000
4 5 6 7 8 9
AA
(p
pb
)
pH
120 C, 40 min
150 C, 15 min
Its presence in food was unknown prior to the Swedish report in 2002.
Found “by chance” when blood samples of exposed workers (miners) and an unexposed control group were compared and high levels of Acrylamide were found in both groups.
0
5
10
15
20
25
30
µg/day
French fries
Bread
Potato chipsCereals
Biscuits & cookies
Coffee
Cakes
Dried Foods
Pop Corn
Salty Snacks
Chocolate Products
Nuts/Seeds/Butters
All other foods
CATEGORY EU DATA FDA DATA
Breads 12-3200 <10-364
Crisp breads <30-1670
Crackers and biscuits <30-2000 26-504
Cereals <30-2300 52-266
Other Grains <30
Potato chips 150-1280 117-2762
Other salty snacks 122-416 12-1168
French fries 85-1104 20-1325
Other potato products <20-12400
Vegetable and fruit
products10-<50 <10-70
Meat < 30-64 < 10-116
Candy and deserts < 20-110 < 10-909
CATEGORY EU DATA FDA DATA
Cookies 36-199
Coffee and Tea 170-700 175-351
Other Nonalcoholic
Beverages < 30
Alcoholic Beverages 30
Dairy Products 10-100 < 10-43
Baby Food and Formula 40-120 < 10-130
Dry Soup Mixes < 10-1184
Gravy and Seasonings 38-54
Amino AcidsLevel of Acrylamide
Formation
Alanine <50 ppb
Asparagine 9270 ppb
Aspartic Acid <50 ppb
Cysteine <50 ppb
Glutamine 156 ppb
Lysine <50 ppb
Methionine <50 ppb
Threonine <50 ppb
Source : Barbara Petersen, Exponent, Inc. October 2002 JIFSAN workshop
• Cheese 40 – 300 mg/100gm• Asparagus 5.4 – 108 mg/100gm• Cocoa (raw) 30.9 mg/100gm
- roasted @ 1250C 14.5 mg/100gm- roasted @ 1350C 9.4 mg/100gm
• Potato 500 – 1000 mg/100gm• Rye 0.2 – 2.8 mg/100gm• Wheat 0.2 – 20 mg/100gm• Corn 0.6 – 1 mg/100gm
Source: Ellin Doyle, Ph.D., Food Research Inst., U. Wisc.
Food product Interval
(month)
Acrylamide level (µg/kg)
Initial Second
Breakfast cereal 12 238 238
Soluble coffee powder 12 771 256
Roasted barley 9 265 225
Roasted coffee 7 203 147
Dried chicory 5 214 174
Roasted chicory 5 4015 3395
Cocoa 3 180 177
Chocolate with
almond
2 94 73
Soluble chocolate
powder
1 54 41
Adapted from Delatour et al.
• Known neurotoxicant (IARC 2002; Manson et al. 2005)
– Peripheral neuropathy
– Tingling/numbness of extremities
– Loss of reflexes
– Chronic CNS dysfunction and neuropathy
• Reproductive toxicity
• Animal carcinogen (CNS, endocrine organs)
• EPA has classified Acrylamide as a B2 carcinogen
(probable human carcinogen) (IRIS2009).
Biomarker – adducts on amino acid valine of Hb.
• 0.3-0.8 micrograms per kg body weight per day
(Office of Environmental Health Hazard Assessment)
• Exposure at a level 1,000 times greater than the MADL
is expected to have no observable effect.
• No Observed Adverse Effect Level (NOAEL) of 15
mg/kg bw/day were identified in mice.
• Legislation under formulation.
• Water extraction
• Analysis by GC-MS with or w/o bromination
• By LC-MS/MS.
• By LC-MS or -UV after derivitization with
mercaptobenzoic acid .
• GC-Ion Trap MS
Acryl amide extracted with water, test
portion homogenized, acidified to pH 4-5
Addition of Carrez I and Carrez II solution
Extraction with Ethylacetate hexane (80:20),
Filtration over Na2SO4
Clean up with Flourisil elution of
acrylamide with acetone
Evaporation, residue taken up in
ethylacetate, triethylamine added
Filtration, injection into GC-MS
GC-MS
method
Asparagine Reducing Sugars- Glucose
- Fructose- Sucrose hydrolysis?
• Factors affecting asparagine and reducing sugars- Variety of potato- Storage conditions- darker the colour of food more is the AA.
1. Reduction or removal of sugars.
Selection of low sugar cultivar.
Blanching and soaking to leach out sugars.
2. Reduction or removal of asparagines.
Use of enzymes to degrade Asparagine during food processing.
Blanching to leach out Asparagine
3. Processing Conditions
Altering time-temperature of processing.
Altering heat processing methods
Changing pH of food by using acids
Use of antioxidants
• Improve agronomic practices
• Select potatoes variety with less Asparagine
• Store potatoes tubers >10°C
• Blanching (82°C)
• Add antioxidants
• Dip slices in citric acid (0.75%) solution
• Dip in NaCl, CaCl2 solution
• Use of enzyme- asparaginase
• Addition of amino acids glycine.
• Adjustment of time and temperature during baking.
• Extend fermentation times where feasible.
• Substitution of ammonium bicarbonate with
alternatives
• Avoid or minimize use of reducing sugars
• Avoidance of very high baking temperature
• Use of asparaginase in dough to degrade Asparagine.
• By treating with asparaginase there was a 99% reduction in the
levels of Acrylamide in the potato mixture.
• Product characteristics fully preserved.
• No change in process parameters.
• Acrylamide formation in thermally processed foods is a major challenges for bakery, French fries and chip producing industries.
• challenges still remain in terms of the needs to develop simple and rapid test methods.
• different pre-frying treatments on the reduction of Acrylamide (AA) formation are under investigation.
• “Foods should not be cooked excessively, for too long or at too high a temperature. However, all food items should be cooked thoroughly to destroy food borne pathogens.”