Analytical solutions today available for measuring 2/3 MCPD and GE and other critical contaminants in food oils J. Kuhlmann, SGS, Hamburg, Germany

Transcription

1 Analytical solutions today available for measuring 2/3 MCPD and GE and other critical contaminants in food oils J. Kuhlmann, SGS, Hamburg, Germany 1

2 Introduction 3-MCPD 3-mono-chloropropane-1,2-diol 3-Chloropropane-1,2-diol + H + X - Free & bound 2-MCPD, 3-MCPD & glycidol -structures Free analytes T 220 C 2-MCPD 2-mono-chloropropane-1,3-diol 2-Chloropropane-1,3-diol +/-H + Cl - Analysis (Fatty acid) Bound analytes just examples, all fatty acids of an oil/fat might be present 3-MCPD glycidol FA 3-MCPD-1,2-bis-palmitoylester 2-MCPD FA 3-MCPD-1-palmitoylester FA FA FA 3-MXPD 2-MCPD-1-oleoyl-3-stearoylester FA: all naturally occurring fatty acids glycidol (2,3-Epoxi-1-propanol) ester-bound 2-/3-MCPD; ester bound glycidol : complex group Glycidylpalmitate of contaminants! 2

3 Introduction Potential hazards of free & bound 2-MCPD, 3-MCPD & glycidol 3-MCPD 2-MCPD Glycidol OR, OR`= OH; various fatty acids Free analytes: Toxicity is related to chlorineor an epoxy group at the molecular backbone. glycidol: genotoxic carcinogen 2A: probably carcinogenic to humans intake should be As-Low-As-Reasonably-Achievable (ALARA) 3-MCPD: non-genotoxic carcinogen 2B: possibly carcinogenic to humans 2-MCPD: No official classification available Bound analytes: During digestion the free analytes are released out of the bound form. EFSA:...the toxicity of 3-MCPD fatty acid esters should be considered equivalent (on a molar basis) to that of the parent compound. j.efsa

4 Introduction Sources Whenever elevated heat is applied to foods free and/or bound MCPD and bound glycidol might be generated! 3-MCPD Refining, (Deodorisation): Bound 2-/3-MCPD, bound glycidol No free MCPD expected! Frying, smoking, roasting, toasting, barbecueing etc.: Bound 2-/3-MCPD, bound glycidol free 2-/3-MCPD HCltreatment Bound 2-/3-MCPD free 2-/3-MCPD Other sources: HCl treatment Migration from contact materials free 2-/3-MCPD 4

5 EC (draft) regulations Introduction Tolarable Maximum Daily Residue Intake(TDI) Limits (MRLs) 3-MCPD year Organisation/source Legal regulation Analyte TDI MRL [µg/kg [mg/kg] bw d] EFSA EU j.efsa /2001 Free Free 3-MCPD & bound in 3-MCPD soy sauce JECFA EU 232/2012 JECFA/83/SC Free 3-MCPD & bound in 3-MCPD glycerol Tolarable Daily Intake(TDI) 3-MCPD 1 st Draft EC regulation year Organisation/source Analyte TDI [µg/kg bw d] Sum of Free 3-monochloropropane-diol (3-MCPD) and Maximum level 1994 SCF Free 3-MCPD 2 3-MCPD fatty acid esters, Basedona expressed draftthis as 3-MCPD (µg/kg) 2007 BfR BfR opinion information is Bound 3-MCPD 2 Vegetable oils and fats intended EFSA for direct human consumption or use j.efsa Free as & an bound ingredient 3-MCPD in food preliminary and can t *** Infant formula and JECFA follow-on JECFA/83/SC formula be taken (powder as official / liquid) Free & bound [ MCPD proposal] 125/15 4 [50/6] *** specification! ***: based on a TDI of 0.8 µg 3-MCPD/kg x bwx d Glycidyl fatty acid esters expressed as glycidol Vegetable oils and fats intended for direct human consumption or use as an ingredient in food 1000 Infant formula and follow-on formula (powder / liquid) / [2019 proposal] 75/10 75/10 [30/4] The EC asked EFSA to review the calculation of TDI for 3-MCPD. ML 3-MCPD might increase. In consequence glycidol regulation might come into force firstly but 3-MCPD regulation at a later time. 5

6 Introduction Recent EC draft regulation 2 nd Draft EC regulation for glycidyl esters (GE) Ref. Ares(2017) /08/ Glycidyl fatty acid esters expressed as glycidol Vegetable oils and fats placed on the market for the final consumer or for use as an ingredient in food with the exception of the foods referred to in Vegetable oils and fats destined Basedona for the production draftthis of baby food and processed cereal-based information food is preliminary and can t Infant formula, follow-on formula and foods for special medical purposes be taken as official intended for infants and young children (powder) specification! Maximum level (µg/kg) until asfrom Infant formula, follow-on formula and foods for special medical purposes intended for infants and young children (liquid) 10 until asfrom When do we expect the first regulation to come into force? The chrystal ball says that regulation will appear the day when higher powers have agreed upon accepted methods. 6

7 Direct vs. indirect analysis: General analytical approaches Direct approaches: analysis of original esters: LC-MS/LC-MS² /LC-MS-TOF Indirect approaches: analysis of released core analytes: Transesterification GC-MS SGS / Unilever glycidol 3-MCPD 2-MCPD glycidol as 3-MBPD Direct analysis shows decreasing prevalence in routine applications due to : Limited availability of reference compounds. Unresolved challenges in the separation of MCPD isomers. Tedious matrix removal. glycidol A: 3-MCPD + glycidol Tf B: 3-MCPD 2-MCPD DGF-A, B: (A-B) x Tf= Glycidol 7

8 Validated methods available for the determination of 3-MCPD & glycidol AOCS Official Methods for the analysis of bound 3-MCPD & bound glycidol in oils & fats or oil-based emulsions alkaline AOCS Cd 29c-13 = DGFC-VI 18 (10) A, B = ISO AOCS Cd 29b-13 = SGS 3-in-1 = ISO proposal transesterification Methods applicable to oils and fats Official methods available for the analysis of free 3-MCPD in foods: AOCS Official Method Method of the official collection of investigation procedures acc. to 35 LMBG CEN TC 275: EN 14573:2004 oils/fats & infant formula not in the methods scopes Both alkaline based methods would cover free MCPD if present! Do the methods cover free 3-MCPD as well??? acidic AOCS Cd 29a-13 = Unilever ISO AOCS Cd for oil-based emulsions The acid based methods supposably would not cover free MCPD! 8

9 Pros and cons Methods applicable to oils and fats Comparison of official methods AOCS Cd 29a,b,c-13 Official method ec time Analytes covered comments Easy Method: Works well with pure, clean oils/fats. AOCS Cd29a-13 Unilever 16 h AOCS Cd29b-13 SGS 3-in-1 16 h AOCS Cd29c min DGF Bound 2-/3-MCPD Bound glycidol (Free MCPD not covered) Does not meet draft regulation! Free& Free& bound bound 2-/3-MCPD 2-/3-MCPD Bound Bound glycidol glycidol Meets draft regulation! Free& Free& bound bound 3-MCPD 3-MCPD Bound Bound glycidol glycidol Meets draft regulation! Overestimations of glycidol observed in some cases in aged or extracted oils and fats. (likelybeingcausedbypresenceof monoacylglycerides [1,2] ) Overestimations of 3-MCPD oberserved when chloride is present during conversion of glycidyl esters, e.g. when the method is applieddirectlytofoods. [3] Ruggedmethod: workswell forall kindsof oils/fats, margarine, can be applied also to many emulsifiers, can be applied directly to many foods without fat extraction. 2 Assays: Double sample preparation. Needs experienced lab staff. Fastest method, may serve for production control Less precise data for glycidol due to calculative approach. 2 Assays: Double sample preparation. Not validated for 2-MCPD. Not as sensitive as AOCS Cd29a,b-13. [1]: J. Kuhlmann, oral presentation: AOCS Expert Panel on Process Contaminants, 2013, Montreal, Canada [2] Z. Zelinkova, A. Giri, T. Wenzel: Food Control, 77, 2017, [3] J. Kuhlmann, oral presentation: 10 th International Fresenius Conference / Contaminants and Residues in Food / 27 th and 28 th October 2015Cologne/Germany 9

10 Automation Methods applicable to oils and fats Users and suppliers have invented automated analysis. [4] R. Zwagerman, P. Overman; A novel method for the automatic sample preparation and analysis of 3-MCPD-, 2-MCPD-, and glycidylesters in edible oils and fats, Eur. J. Lipid. Sci. Technol. 2016, 118(7), Sponsor presentationatthedgf Symposium, June 2017, Berlin, Germany DGF-C-VI 18 (10) method prevalent. More sophisticated technique: e.g. robot samplers, backflush, GC-MS² Fat extraction from compound foods is not to be part of automation. Matrix removal might be not as good as in manually performed sample clean-up Caution: Due to modifications automated methods might not be covered by official validation, it is in-house validated methods. 10

11 Recent method developments Methods applicable to oils and fats The LOQ of this method was 0.01 μgof 2-MCPD and 3-MCPD and μg of glycidol TP273.pdf AOCS Cd29a-13 ( Unilever ) GC-MS-MS In-housevalidated 3-in-1 low-loq LOQ 2-MCPD = mg/kg LOQ 3-MCPD = mg/kg LOQ glycidol = mg/kg in oils/fats [6]J. Kuhlmann; Analysis and occurrence of dichloropropanol fatty acid esters and related process-induced contaminants in edible oils and fats; Eur. J. Lipid. Sci. Technol. 2016,118(3), AOCS Cd29b-13 ( 3-in-1 ) modified GC-MS 11

12 Methods applicable to oils and fats Trends from perspective of a routine laboratory N of samples Customers requestsatsgs lab formcpd-& glycidol analysis (2017 estimated) 3-in-1 = AOCS Cd 29b-13 DGF= AOCS Cd 29c-13 Free MCPD (& DCPs) Unilever= AOCS Cd 29a-13 In case of external analysis there might be a trend to use the 3-in-1 application. For in-house analysis, manufacturers seem to prefer the DGF - and the Unilever -approach. 12

13 New methodological applications Recent approaches for the analysis of infant formulae [-] Wöhlin F, Fry H, Lahrssen-Wiederholt, Preiss- Weigert A: Occurrenceof fatty acid esters of 3- MCPD, 2-MCPD and glycidol in infant formula. Food Addit. Contam., 2015, 32(11), BfR-method* ASE + AOCS Cd29a-13 * BfR assumes restrictions due to possible glycidol-overestimations[2] [-] A. Becalski, T. Zhao, S. Feng, B.P.-Y. Lau; A pilot survey of 2-and 3-monochloro-propanediol and glycidol fatty acid esters in baby formula on the Canadian market ; J. Food Compos. Anal., 2015, 44, Health Canada l/l-extraction + direct GEdetermination + indirect 2-& 3- MCPD-determination [-] J. Leigh, S MacMahon; Extraction and Liquid Chromatography-Tandem Mass Spectrometry Detection of 3-Monochloropropanediol Esters and Glycidyl Esters in Infant Formula, J. Agric. Food Chem., 2016, 64 (49), FDA l/l-extraction+ 2 x SPE² + 2 x direct 3-MCPD & GEdetermination Draft AOAC MCPD SMPR 2017.XXX; Version 8; July 25, 2017 Determination of overall 2-and 3-MCPD, 2-and 3-MCPD esters and glycidyl esters in powdered milk, infant and adult/pediatric nutritional formula 13

14 Methods for analysis of other foods JRC approach for compound foods EU reference laboratory JRC/IRMM: In-house-validated method for the separate analysis of free 2-/3-MCPD & bound 2-/3-MCPD and glycidol in foods [7] [7]: EFSA supporting publication 2015: EN-779: T. Wenzel et al. bound 2-/3-MCPD/glycidol A) Petrol ether/acetone/ i-hexane(2+1+2, v/v/v) Data Points for> to600 consider samplessubmitted for routine analysis: toefsa Use of liquid nitrogen for grinding(safety). Critical points: PLE worksserially& islaborious. Use of liquid nitrogen for grinding(safety). tbmehasa weakextractionefficiency thismethodis TBME has a weak extraction efficiency. not applicable to infant formula. Addition of istds after extraction is not best practise. Addition of istds after extraction is not best practice. Risk of glycidol-overestimation with AOCS Cd 29a-13. Risk of glycidol-overestimation with AOCS Cd 29a-13. Validation trialincludingmodificationsin progress. Recent modifications: A) Other solvents for infant formula. B) Additional SPE Free 2-& 3-MCPD B) Solid-Phase-Extraction; n-hexane/ethylacetate(85+15, (v/v)) AOCS Cd 29a-13 ( Unilever ) Fit for purpose as routine method? Serious doubts about applicability to all kinds of infant formula. 14

15 Analysis of other foods SGS 5-in-2 low LOQ approach for compound foods Extraction * + 3-in-1 low-loq *HUPsSE: Heat-Ultrasonic-Pressure supported Solvent Extraction Applicable to compound foods as spreads, bakery ware, chips, fries, fish, infant formula. 2 g sample + free& boundinternalstandards-d 5 HUPsSE: Triple ultrasonicextractionatt 65 o C 3 x 6 ml: MeOH // MeOH/tBME1:1 // tbme Solvent evaporation by flow of nitrogen 3-in-1 low-loq AOCS Cd29b-13 modified Ester bound2-& 3-MCPD & glycidol LOQ: 10 µg/kg product l/l-separation non-polar polar aqueous samples (milk etc.: extraction acc. to Röse-Gottlieb) Derivatisation& GC- MS analogue to 3-in-1 Free 2-& 3-MCPD LOQ: 5 µg/kg product > 1000 foodsamplesincluding> 200 infantformulaefromthegerman marketanalysedin 2016 on behalf of the Federal German Ministry of Food and Agriculture. Results reported to EFSA. 15

16 Conclusions Summary: Trends in MCPD & glycidol analysis. Draft regulation applies for free & bound 3-MCPD and bound glycidol. Regulation of glycidol might come into force prior to regulation of 3-MCPD. At present not all of the validated methods available for oils/fats do match with the draft EC regulation. Current attempts are made for development and validation of analytical methods for the determination of free and bound 3-MCPD and bound glycidol in compound foods and especially infant formula. In-house validated methods with improved sensitivity as well as automated solutions are in use for routine analysis. 16

17 Alternative use of empty solvent bottles! SGS Germany GmbH Dr. Jan Kuhlmann Weidenbaumsweg 137 D Hamburg Tel.: +49 (0) mobile: +49 (0) Thank you for your kind attention! 17