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SYMPOSIUM ON FOOD CHEMISTRY AND QUALITY ASSURANCE

SYMPOSIUM ON FOOD CHEMISTRY AND QUALITY ASSURANCE. Alan Richards. Head of Scientific Services Public Analyst (2m population) Official Agricultural Analyst President Association Public Analysts. Summary. History of Food Adulteration in UK Public Analyst Links to Enforcement

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SYMPOSIUM ON FOOD CHEMISTRY AND QUALITY ASSURANCE

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  1. SYMPOSIUM ON FOOD CHEMISTRY AND QUALITY ASSURANCE

  2. Alan Richards Head of Scientific Services Public Analyst (2m population) Official Agricultural Analyst President Association Public Analysts

  3. Summary • History of Food Adulteration in UK • Public Analyst Links to Enforcement • Legal Qualification (MChemA) • MChemA Examination • Certificates of Analysis • EU Methods and UK Analysis • Test Methods • Food Complaints • Other work of Public Analysts

  4. UNITED KINGDOM

  5. DURHAM

  6. HISTORY OF FOOD ADULTERATION • 1200 AD – KING HENRY II “GARBLE” • 1700 AD – STEADY INCREASE • 1800 AD – INDUSTRIAL REVOLUTION

  7. 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. AND METHODS 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 SMALL 1820.

  8. Frederick Accum http://www.gutenberg.org/etext/19031

  9. 1851 - 54 • ARTHUR HILL HASSALL Purchased and analysed 2500 articles of food and produced reports in the medical journal The Lancet identifying many examples of adulteration of foods. Information Link: http://www.rsc.org/Education/EiC/issues/2005Mar/Thefightagainstfoodadulteration.asp

  10. Origin of UK Food Law ·1860 ADULTERATION OF FOOD AND DRINKS ACT ·1872 ADULTERATION OF FOOD AND DRUGS ACT ·1875 SALE OF FOOD AND DRUGS ACT ·1899 SALE OF FOOD AND DRUGS ACT ·1928 FOOD AND DRUGS ADULTERATION ACT ·1938 FOOD AND DRUGS ACT ·1955 FOOD AND DRUGS ACT ·1980 FOOD ACT ·1990 FOOD SAFETY ACT 1999 FOOD STANDARDS AGENCY

  11. Modern Public Analysts English Law Courts Trading Standards Environmental Health Government Chemist Public Analyst Central Science Lab Food Standards Agency Consumers Industry

  12. QUOTATION • “The duties of the Public Analyst are daily increasing in complexity and difficulty. Higher qualifications than formerly are required of him, owing not only to the general advance in science as applied to the analysis of food, but also the exacting character of the numerous regulations of government departments concerned. . . . “ • September 1923

  13. Mastership in Chemical Analysis

  14. Food Safety Act Certificate

  15. The MChemA Examination • Theory of analytical instrumentation, • QA and statistics, • Methods of testing, • Laws relating to food, water and animal feeds • Practical application of skills • Ability to write certificates of analysis

  16. MChemA Questions • Day 1 • Theory of Analytical Chemistry, 3 hours, • Methods of analysis food, drugs & water 3 hours • Day 2 • law related to food, drugs and water, lab administration • identify the six unknown substances using the microscope • Day 3, 4 and 5 • Practical Demonstration of Skills http://www.rsc.org/Education/Qualifications/MChemA/Index.asp

  17. Certificates of Analysis Food Safety Act • The FACTS • The STANDARD • The INTERPRETATION

  18. Certificates of Analysis • Food Complaint Certificate • Full History • Photographs • Results of Analysis • Interpretation • None Technical Report

  19. Other Certificates • Agriculture Act Certificates • Statements of Witness • UKAS

  20. Official Food Labs

  21. Other Work

  22. Other Work

  23. UK Food Laws • Pre 1980 – mostly set by UK • EU Influence • EU Methods of Analysis • Contaminants in Food Regulation 2007 • Commission Regulation (EC) No 1881/2006 of 19 December 2006 • Commission Directive 2001/22/EC

  24. Commission Directive 2001/22/EC • ØSpecific methods for the determination of lead, cadmium and mercury • contents are not prescribed. • ØLaboratories shall use a validated method that fulfils the performance • criteria indicated in Table 3. • ØWhere possible, the validation shall include a certified reference material in • the collaborative trial test materials. • ØLOD - 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 than 0,1 mg/kg. For the latter, no more than one fifth of the value of the specification • ØLOQ - 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 mg/kg. For the latter, no more than two fifths of the value of the specification. • ØPrecision HORRATr or HORRATR values of less than 1,5 in the validation • collaborative trial • ØRecovery 80-120 % • Specificity - Free from matrix or spectral interferences

  25. UK and EU Laws When searching for UK regulations I need the date of the regulation and the statutory instrument (SI) number. All current regulations are available on the internet on the website: http://www.opsi.gov.uk/ 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 website at: http://www.publicanalyst.com/

  26. Sampling • Formal Sampling – passing on • Informal Sampling • Complaints • Regulation sampling • Projects • Surveillance

  27. Glass Contamination

  28. Fibres Human Hair Mouse Hair

  29. Faecal Contamination

  30. Moulds

  31. Infestation

  32. Cod Haddock Coley Salmon Authenticity

  33. ‘Stretching’ with neutral spirit (cereal or non–cereal derived) • Geographic mislabelling • Addition of flavourings • Addition of sweetening Modes of Adulteration • Mislabelling of age

  34. Chromatographic Analysis of Distilled Spirits Major Volatile Congeners (Mostly alcohols and esters) Compound Polarity BP (°C) Concentration range Methanol Propanol Isobutanol 2-methyl-1-butanol Isoamyl alcohol Ethyl acetate Isoamyl acetate polar polar polar polar polar polar ? polar ? 65 97 108 130 130 77 142 9 – 82 60 – 1330 150 – 620 1 – 360 0 – 770 44 – 500 2 - 25

  35. Modes of Adulteration

  36. Cask Extractives

  37. Stable isotope analysisin food authentication Detecting the substitution of Organic crops with conventional produce Simon Kelly1 & Alison Bateman2 1 Institute of Food Research, Norwich, UK, NR4 7UA (simon.kelly@bbsrc.ac.uk) 2 University of East Anglia, Norwich, UK, NR4 7JT

  38. ‘light’ isotope ‘heavy’ isotope - - - - - - - - - - - - - 14N 15N 7 7 P 7 N 7 P 7 N 8 99.63 % 0.37 % Stable Isotopes of Nitrogen

  39. Tomatoes – normal distn

  40. Tomato Data - 3-D Scatter Plot for variables d15N‰, Mn (ppm), Cu (ppm) & Rb (ppm)

  41. A METHOD FOR THE SIMULTANEOUS DETERMINATION OF SWEETENERS IN FOODS • Steve Appleton • Durham Scientific Services • steve.appleton@durham.gov.uk

  42. Evaporative Light Scattering Detector (ELSD) Gaining popularity as a universal detector. Simple three step process • Nebulisation – column effluent forms a dispersion of droplets • Evaporation – mobile phase is evaporated, leaving a fine mist of dried sample. • Detection – laser light scattered by sample particles is detected, generating an electrical signal.

  43. Evaporative Light Scattering Detector (ELSD) Pro • since all particles scatter light, all sample components are detected, regardless of their structure or optical properties. Con • method limitations as it can only be used with volatile mobile phases and mobile phase modifiers

  44. ELSD

  45. ELSD plus UV

  46. Elisa and DNA • Protein • Heat labile • Cross reactivity • Batch variation • DNA • Cooked foods • Specific • Simplified “lab on a chip”

  47. Lab on a Chip

  48. DNA Analysis • Applications • Fish & meat speciation • Basmati rice authenticity • Detection of bushmeat • GMO testing • Fruit juices • Durum wheat

  49. Fish Speciation • Method uses PCR-RFLP • A region of a specific gene is amplified by PCR using universal primers • Produces a single PCR product of the same size from all samples • Can be done on raw, cooked and some canned fish (not tuna) • No need for a reference specimen

  50. DNA Results

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