Presentation on theme: "Presentation title Presentation subhead Survey on nutrient measurements in laboratories (Task 3) Objectives 1.The need of using similar analytical methods."— Presentation transcript:
Presentation title Presentation subhead Survey on nutrient measurements in laboratories (Task 3) Objectives 1.The need of using similar analytical methods for micronutrient measurements throughout Europe. 2.Identify protocols for nutrient measurement in laboratories, assess their validity and suggest improvements which will lead to new laboratory standards and/or methods.
3 What to Do Search for methods for analysis of micronutrients in Europe (e.g. vitamins, fatty acids, minerals, phytonutrients) Collate the methods. Find out advantages and disadvantages of the methods in measuring the levels of those micronutrients in food and food products. Study the problems and difficulties suggested. Suggest any possible modifications in the analysis of these components. Propose protocols that could be used throughout European analytical laboratories that could combine all the benefits of each specific analysis of the micronutrients
5 Laboratories and Methods Minerals in Food (Cu, Se, Ca, Cu, Fe, Mg, Zn, Li) Total no of Labs127 Method AAS77 Method GFAAS17 Method Hydride14 Method ICP MS10 Method ICP OES9
6 Laboratories and Methods Minerals in Water (Cu, Se, Ca, Cu, Fe, Mg, Zn) Total no of Labs440 Method AAS86 Method GFAAS19 Method titrimetric 19 Method ICP MS115 Method ICP OES 201
7 Laboratories and Methods Vitamin B12 Total no of Labs23 Method ELISA3 Method HPLC10 Method Microbiological10
8 General Comments 1.For methods with the number of laboratories reporting less than 3, no comments can be made. 2.AAS means Atomic Absorption Spectrophotometer 3.GFASS mean Graphite Furnace AAS 4.Hydride means Hydride Generator Technique 5.ICP means Inductive Coupled Plasma Spectrophotometer 6.ICP OES mean ICP optical emission Spectrophotometer 7.ICP MS means ICP mass selective Spectrophotometer
9 Comments For Iodine It appears that the use of ICP - MS give an accurate measurement with no failing rates in performing the analyses. The use of other methods appear to be problematic.
10 Comments For Vitamins It appears that today's methods do not always give an accurate measurement with a large failing rate.
11 Possible problems in the analytical procedure (Food Micronutrient Analyses) Ashing procedurePossible ProblemsMicrowave ProcedurePossible Problems Ashing at High Temperature Loss of measurands and/or sample SamplingSmall size sample FilteringLoss of sample and/or contamination Dedicated containers for MW Possible contamination DilutionArithmetic error or not cleaned containers DigestionFor multi-samples different procedures are needed Moisture determination Arithmetic error and/or sample loss About 4 hours are needed About one hour is needed
12 Plus in the analytical procedure Ashing procedureMicrowave Procedure High Sample massNo sample Loss Single Sample procedureNo filtering req. Low Cost of consumablesDigestion complete Less expensive equipmentQuicker
13 ICP-OES Vs ICP-MS Water at mg/lSimilar Performance (8-11% failure rate) Water at μg/lBetter OES performance Possible Reason: The ICP-MS is a new instrument in the market and the experience in its use not quite as good The environmental conditions affect the ICP-MS
14 Vitamins Three methods are used today for the determination of Vitamins: –HPLC –Microbiological –Eliza A number of problems appear in any of the above methods. There is no evidence that one of the method is more successful than the rest, mainly due to the small size of the samples received. There is a general ‘feeling’ that the HPLC methods should be given a push. This is mainly due to the smaller time required to perform the analyses (as compared to the microbiological). It appears that the laboratories are not willing to participate in PTs. This is mainly due to the problematic participations and the frequent failures.
15 Suggestion To continue to work on Vitamins. Meaning: –Collaborate with Universities, official bodies, and/or other laboratories to examine the methods experimentally and possibly develop methods for vitamin determination.
16 Dissemination Already 1.Presented the Work to a.The Council of the Cyprus Association of Dieticians and Nutritionist b.The Council of the Cyprus Consumer Association c.An effort will be made to present the work to the conference of the Dieticians and Nutritionists in Cyprus (Nov., 2008) 2.Article on the findings was accepted for publication by the Journal of Accreditation and Quality Assurance (reviewed Journal)