1 symposium on food chemistry and quality assurance
TRANSCRIPT
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Alan Richards
Head of Scientific ServicesHead of Scientific Services
Public Analyst (2m population)Public Analyst (2m population)
Official Agricultural AnalystOfficial Agricultural Analyst
President Association Public AnalystsPresident Association Public Analysts
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Summary History of Food Adulteration in UKHistory of Food Adulteration in UK Public Analyst Links to EnforcementPublic Analyst Links to Enforcement Legal Qualification (MChemA)Legal Qualification (MChemA) MChemA ExaminationMChemA Examination Certificates of AnalysisCertificates of Analysis EU Methods and UK AnalysisEU Methods and UK Analysis Test MethodsTest Methods Food ComplaintsFood Complaints Other work of Public AnalystsOther work of Public Analysts
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HISTORY OF FOOD ADULTERATION
1200 AD – KING HENRY II “GARBLE”1200 AD – KING HENRY II “GARBLE”
1700 AD – STEADY INCREASE1700 AD – STEADY INCREASE
1800 AD – INDUSTRIAL REVOLUTION1800 AD – INDUSTRIAL REVOLUTION
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In 1820 A TREATISE ON
ADULTERATIONS OF FOOD,AND CULINARY POISONS.
EXHIBITING
The Fraudulent Sophistications of
BREAD, BEER, WINE, SPIRITOUS LIQUORS, TEA, COFFEE, CREAM, CONFECTIONERY, VINEGAR, MUSTARD, PEPPER, CHEESE, OLIVE
OIL, PICKLES,AND OTHER ARTICLES EMPLOYED IN DOMESTIC ECONOMY.
ANDMETHODS OF DETECTING THEM.
By Fredrick Accum,
OPERATIVE CHEMIST, AND MEMBER OF THE PRINCIPAL ACADEMIES AND SOCIETIES OF ARTS AND SCIENCES
IN EUROPE.Philadelphia:
PRINTED AND PUBLISHED BY AB'M SMALL1820.
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1851 - 54 ARTHUR HILL HASSALLARTHUR HILL HASSALL
Purchased and analysed 2500 articles of food Purchased and analysed 2500 articles of food and produced reports in the medical journal and produced reports in the medical journal The Lancet identifying many examples of The Lancet identifying many examples of adulteration of foods.adulteration of foods.
Information Link:Information Link:http://www.rsc.org/Education/EiC/issues/2005Mar/Thefightagainstfoodadulteration.asp
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Origin of UK Food Law
18601860 ADULTERATION OF FOOD AND DRINKS ACTADULTERATION OF FOOD AND DRINKS ACT
18721872 ADULTERATION OF FOOD AND DRUGS ACTADULTERATION OF FOOD AND DRUGS ACT
18751875 SALE OF FOOD AND DRUGS ACTSALE OF FOOD AND DRUGS ACT
18991899 SALE OF FOOD AND DRUGS ACTSALE OF FOOD AND DRUGS ACT
19281928 FOOD AND DRUGS ADULTERATION ACTFOOD AND DRUGS ADULTERATION ACT
19381938 FOOD AND DRUGS ACTFOOD AND DRUGS ACT
19551955 FOOD AND DRUGS ACTFOOD AND DRUGS ACT
19801980 FOOD ACTFOOD ACT
19901990 FOOD SAFETY ACTFOOD SAFETY ACT
19991999 FOOD STANDARDS AGENCYFOOD STANDARDS AGENCY
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Modern Public Analysts
Public Analyst
Industry
Food Standards
Agency
Government Chemist
Environmental Health
Consumers
Trading Standards
Central Science Lab
English Law Courts
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QUOTATION ““The duties of the Public Analyst are daily The duties of the Public Analyst are daily
increasing in complexity and difficulty. increasing in complexity and difficulty. Higher qualifications than formerly are Higher qualifications than formerly are required of him, owing not only to the required of him, owing not only to the general advance in science as applied to general advance in science as applied to the analysis of food, but also the exacting the analysis of food, but also the exacting character of the numerous regulations of character of the numerous regulations of government departments concerned. . . .government departments concerned. . . . “ “
September 1923September 1923
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The MChemA Examination
Theory of analytical instrumentation, Theory of analytical instrumentation, QA and statistics, QA and statistics, Methods of testing, Methods of testing, Laws relating to food, water and animal Laws relating to food, water and animal
feedsfeeds Practical application of skillsPractical application of skills Ability to write certificates of analysisAbility to write certificates of analysis
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MChemA Questions Day 1Day 1
Theory of Analytical Chemistry, 3 hours,Theory of Analytical Chemistry, 3 hours, Methods of analysis food, drugs & water 3 hoursMethods of analysis food, drugs & water 3 hours
Day 2 Day 2
law related to food, drugs and waterlaw related to food, drugs and water, lab administration, lab administration identify the six unknown substances using the microscopeidentify the six unknown substances using the microscope
Day 3, 4 and 5Day 3, 4 and 5 Practical Demonstration of SkillsPractical Demonstration of Skills
http://www.rsc.org/Education/Qualifications/MChemA/Index.asp
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Certificates of Analysis
Food Safety ActFood Safety Act
The FACTSThe FACTS
The STANDARDThe STANDARD
The INTERPRETATIONThe INTERPRETATION
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Certificates of Analysis
Food Complaint CertificateFood Complaint Certificate Full HistoryFull History PhotographsPhotographs Results of AnalysisResults of Analysis InterpretationInterpretation None Technical ReportNone Technical Report
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Other Certificates
Agriculture Act CertificatesAgriculture Act Certificates
Statements of WitnessStatements of Witness
UKAS UKAS
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UK Food Laws Pre 1980 – mostly set by UKPre 1980 – mostly set by UK EU InfluenceEU Influence EU Methods of AnalysisEU Methods of Analysis
Contaminants in Food Regulation 2007Contaminants in Food Regulation 2007 Commission Regulation (EC) No 1881/2006Commission Regulation (EC) No 1881/2006
of 19 December 2006of 19 December 2006 Commission Directive Commission Directive 2001/22/EC2001/22/EC
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Commission Directive 2001/22/EC
Specific methods for the determination of lead, cadmium and mercury Specific methods for the determination of lead, cadmium and mercury contents are not prescribed.contents are not prescribed.
Laboratories shall use a validated method that fulfils the performance Laboratories shall use a validated method that fulfils the performance criteria indicated in Table 3.criteria indicated in Table 3.
Where possible, the validation shall include a certified reference material in Where possible, the validation shall include a certified reference material in the collaborative trial test materials.the collaborative trial test materials.
LOD - No more than one tenth of the value of the specification in LOD - No more than one tenth of the value of the specification in Regulation (EC) No 466/2001, except if the value of the specification for lead is less Regulation (EC) No 466/2001, except if the value of the specification for lead is less
than 0,1 mg/kg. For the latter, no more than one fifth of the value of the specificationthan 0,1 mg/kg. For the latter, no more than one fifth of the value of the specification LOQ - No more than one fifth of the value of the specification in Regulation LOQ - No more than one fifth of the value of the specification in Regulation
(EC) No 466/2001, except if the value of the specification for lead is less than 0,1 (EC) No 466/2001, except if the value of the specification for lead is less than 0,1 mg/kg. For the latter, no more than two fifths of the value of the specification.mg/kg. For the latter, no more than two fifths of the value of the specification.
Precision HORRATPrecision HORRATrr or HORRAT or HORRATRR values of less than 1,5 in the validation values of less than 1,5 in the validation collaborative trial collaborative trial
Recovery 80-120 % Recovery 80-120 %
Specificity - Free from matrix or spectral interferencesSpecificity - Free from matrix or spectral interferences
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UK and EU LawsWhen searching for UK regulations I need the date of the regulation and When searching for UK regulations I need the date of the regulation and
the statutory instrument (SI) number. All current regulations are the statutory instrument (SI) number. All current regulations are available on the internet on the website:available on the internet on the website:
http://www.opsi.gov.uk/ EC regulations can be found on the website:EC regulations can be found on the website:
http://eur-lex.europa.eu/en/index.htm The public analyst website offers a list of current regulations on their The public analyst website offers a list of current regulations on their
website at:website at:
http://www.publicanalyst.com/
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Sampling
Formal Sampling – passing onFormal Sampling – passing on
Informal SamplingInformal Sampling
ComplaintsComplaints
Regulation samplingRegulation sampling
ProjectsProjects
SurveillanceSurveillance
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Modes of AdulterationModes of Adulteration
Mislabelling of age Mislabelling of age
‘Stretching’ with neutral spirit (cereal or non–cereal derived)
‘Stretching’ with neutral spirit (cereal or non–cereal derived)
Geographic mislabelling Geographic mislabelling
Addition of flavourings Addition of flavourings
Addition of sweetening Addition of sweetening
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MethanolPropanolIsobutanol2-methyl-1-butanolIsoamyl alcohol
Ethyl acetateIsoamyl acetate
MethanolPropanolIsobutanol2-methyl-1-butanolIsoamyl alcohol
Ethyl acetateIsoamyl acetate
polarpolarpolarpolarpolar
polar ?polar ?
polarpolarpolarpolarpolar
polar ?polar ?
6597
108130130
77142
6597
108130130
77142
9 – 8260 – 1330150 – 620
1 – 3600 – 770
44 – 5002 - 25
9 – 8260 – 1330150 – 620
1 – 3600 – 770
44 – 5002 - 25
PolarityPolarityCompoundCompound BP (°C)BP (°C) Concentration rangeConcentration range
Chromatographic Analysis of Distilled Spirits
Chromatographic Analysis of Distilled Spirits
Major Volatile Congeners (Mostly alcohols and esters)Major Volatile Congeners (Mostly alcohols and esters)
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Modes of AdulterationModes of Adulteration
min2 4 6 8 10 12 14 16 18
pA
15
20
25
30
35
Ace
tald
ehyd
e
Eth
yl A
ceta
teA
ceta
l
Met
han
ol
n-P
ropa
nol is
o-B
utan
ol
iso-
Am
yl A
ceta
te
n-B
utan
ol
2-M
ethy
l-1-B
uta
nol
3-M
ethy
l-1-
But
anol
n-P
enta
nol
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min10 15 20 25
mAU
75
80
Gal
lic A
cid
HM
F
Syr
ingi
c A
cid
Van
illin Syr
inga
ldeh
yde
Sco
pole
tin
Con
ifera
ldeh
yde
Sin
apal
deh
yde
min10 15 20 25
mAU
0
5
10
15
20
25
30
35
Signal=260nm
Van
illic
Aci
d
Ella
gic
Aci
d
79
78
77
76
Signal=280nm+340nm
Cask ExtractivesCask Extractives
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Stable isotope analysisin food authentication
Simon Kelly1 & Alison Bateman2
1 Institute of Food Research, Norwich, UK, NR4 7UA ([email protected])2 University of East Anglia, Norwich, UK, NR4 7JT
Detecting the substitution of Organic crops with conventional produce
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Stable Isotopes of NitrogenStable Isotopes of Nitrogen
-
--
- --
P 7N 7
- -
--
- --
P 7N 8
‘light’ isotope ‘heavy’ isotope
14N7 15N7
99.63 % 0.37 %
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Tomatoes – normal distn
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20
-10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20d15N(‰)air
Pro
bab
ilit
y
Conventional
Organic
n=43Mean = -0.1n-1 = 2.1
n=61Mean = +8.1 n-1 = 3.2
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20
-10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20d15N(‰)air
Pro
bab
ilit
y
Conventional
Organic
n=43Mean = -0.1n-1 = 2.1
n=61Mean = +8.1 n-1 = 3.2
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A METHOD FOR THE SIMULTANEOUS
DETERMINATION OF SWEETENERS IN FOODS
Steve AppletonSteve Appleton Durham Scientific ServicesDurham Scientific Services
[email protected]@durham.gov.uk
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Evaporative Light Scattering Detector (ELSD)
Gaining popularity as a universal detector.Gaining popularity as a universal detector.
Simple three step processSimple three step process Nebulisation – column effluent forms a Nebulisation – column effluent forms a
dispersion of dropletsdispersion of droplets Evaporation – mobile phase is evaporated, Evaporation – mobile phase is evaporated,
leaving a fine mist of dried sample.leaving a fine mist of dried sample. Detection – laser light scattered by sample Detection – laser light scattered by sample
particles is detected, generating an particles is detected, generating an electrical signal.electrical signal.
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Evaporative Light Scattering Detector (ELSD)
Pro Pro since all particles scatter light, all since all particles scatter light, all
sample components are detected, sample components are detected, regardless of their structure or optical regardless of their structure or optical properties.properties.
Con Con method limitations as it can only be method limitations as it can only be
used with volatile mobile phases and used with volatile mobile phases and mobile phase modifiers mobile phase modifiers
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Elisa and DNA ProteinProtein
Heat labileHeat labile Cross reactivityCross reactivity Batch variationBatch variation
DNADNA Cooked foodsCooked foods SpecificSpecific Simplified “lab on a chip”Simplified “lab on a chip”
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DNA Analysis
ApplicationsApplications Fish & meat speciationFish & meat speciation Basmati rice authenticityBasmati rice authenticity Detection of bushmeatDetection of bushmeat GMO testingGMO testing Fruit juicesFruit juices Durum wheatDurum wheat
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Fish Speciation
Method uses PCR-RFLPMethod uses PCR-RFLP A region of a specific gene is amplified A region of a specific gene is amplified
by PCR using universal primersby PCR using universal primers Produces a single PCR product of the Produces a single PCR product of the
same size from all samplessame size from all samples Can be done on raw, cooked and some Can be done on raw, cooked and some
canned fish (not tuna)canned fish (not tuna) No need for a reference specimenNo need for a reference specimen
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DNA ResultsFish Species 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 320 330 340 350
Atlantic cod
Pacific cod
Alaskan Pollack
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Reminder
A A WRONGWRONG RESULT RESULT
IS WORSEIS WORSE
THAN NO RESULT AT ALL !THAN NO RESULT AT ALL !