Browsing by Subject "validointi"

3-Chloro-1,2-propanediol (3-MCPD), 2-chloro-1,3-propanediol (2-MCPD) and 2,3-epoxy-1-propanol (glycidol) and their fatty acid esters are contaminants formed during processing fat containing foodstuffs at high temperatures. Mainly MCPD and glycidyl esters have been found to be formed in the deodorization process of oils, and in vegetable oils, such as palm oil, they have been measured at high concentrations. In accordance with the restrictions imposed by the European Commission, the levels of glycidyl esters must be especially monitored, as they have been identified as potentially carcinogenic compounds. The aim of the study was to introduce and validate a gas chromatographic analysis method for glycidyl esters and MCPD esters for the Customs Laboratory. The method was validated for two matrices: first for oils and then for powdered infant formulas. In addition, the success of the validation was examined by analyzing various oil samples previously received by the Customs Laboratory. The Customs Laboratory is also involved in the activities of the European Union Reference Laboratory, for which it was intended to participate in the reference measurement organized by the EU Reference Laboratory. The method for the determination of 3-MCPD, 2-MCPD and glycidyl esters in oils and infant formulas was carried out according to the guidelines of the European Union Reference Laboratory for Contaminants (EURL-PC). Determination of MCPD and glycidyl ester concentrations in oils and infant formulas included the following steps: fat extraction by liquid-liquid extraction (for infant formulas), addition of standards, solid-phase extraction, conversion of glycidyl esters to 3-MBPD esters, transesterification, neutralization, salting out, derivatization and analysis with gas chromatography-mass spectrometry system. Concentrations were determined using internal standard method. The method was validated for the following parameters: specificity, selectivity, limit of detection and quantitation, reproducibility, repeatability, trueness, linearity and working range, stability and measurement uncertainty. The analytical method developed for the determination of MCPD and glycidyl esters was successfully validated for oils and powdered infant formulas. The developed method proved to be specific and selective. The limit of determination was found to be 6.3 µg/kg, 1.3 µg/kg and 0.8 µg/kg for the oil matrix 3-MCPD, 2-MCPD and glycidyl esters. The limits of determination for the infant formula were 5.4 µg/kg, 3.0 µg/kg and 1.6 µg/kg for 3-MCPD, 2-MCPD and glycidyl esters. Recoveries for MCPD and glycidyl esters in the oil and powdered infant formulas were 83-105%. R2 for calibration lines were greater than 0.99, and the lines were linear over the entire measurement range of 2-1000 µg/kg. The relative standard deviation of repeatability and reproducibility was less than 20% for both matrices. The expanded measurement uncertainty for the MCPD and glycidyl esters of the oil and powdered infant formula was less than 50%. For all parameters, the requirements set by the Customs Laboratory and the performance requirements of Regulation (EU) 1881/2006 were met. A method validated for two matrices can then be accredited. The customs laboratory may use the developed method in the future to control 3-MCPD, 2-MCPD and glycidyl esters levels of oils and powdered infant formulas. In the future, the method could also be validated for new matrices, such as liquid infant formulas.

Merkittävä osa elintarvikeperäisistä mikrobiologisista ja kemiallisista vaaroista kasvaa, leviää tai syntyy kuluttajien kotona. Kuluttajat vaikuttavat ruoan turvallisuuteen käsittely- ja säilytystottumuksillaan, joiden arviointi on nykyisessä riskinarvioinnissa vaikeaa puutteellisen aineiston takia. Jotta riskinarviointi olisi paikkansapitävä, ja sen mukaan luodut ohjeistukset, säädökset ja lait mahdollisimman kohdennettuja, tulee kuluttajien vaaroille altistumisen arviointi olla aiempaa tarkempaa. Tutkimus suoritettiin Ruokaviraston toimeksiantona, ja sen tarkoitus oli luoda valmis kyselypohja riskinarvioinnin tueksi. Kyselylomakkeiden avulla pyrittiin selvittämään kuluttajien kalan ja lihan käsittely- ja säilytystottumuksia kotioloissa, millä on merkittävä vaikutus kemiallisille ja mikrobiologisille vaaroille altistumisessa. Tutkimus koostui kahden kyselylomakkeen luomisesta ja niiden validiuden arvioimisesta yksilöhaastatteluilla (n=30, 18–83 v.). Tutkimuksessa havaittiin, että lomakkeet eivät sellaisenaan olleet valmiita käyttöönottoon. Osa kysymyksistä ei soveltunut haluttuun tarkoitukseen, eikä niillä täten saatu kerättyä tarvittavaa aineistoa. Ennen lomakkeiden käyttöönottoa myös kyselyissä käytettyä 7-portaista ankkuroitua asteikkoa tulee muokata numeerisemmaksi, sillä sanalliset ankkurit olivat monitulkintaisia. Tässä tutkimuksessa ehdotettujen muokkausten jälkeen lomakkeiden validiteetti olisi tärkeää tutkia myös seurantatutkimuksen avulla, mutta myös sellaisenaan lomakkeet tuovat tarvittavaa aineistoa kuluttajien kotikäyttäytymisestä.