Paraffins In Food Research Articles

Application of the GC-HRMS based method for monitoring of short- and medium-chain chlorinated paraffins in vegetable oils and fish

The aim of this study was to develop methods for the determination of short- and medium-chain chlorinated paraffins (SCCPs; MCCPs) in vegetable oils and fish employing gas chromatography coupled with high-resolution mass spectrometry because of a lack of information on the presence of chlorinated paraffins in food consumed in Europe.For isolation of CPs from fish, an ethyl acetate extraction followed by a clean-up of the extract by gel permeation chromatography was performed. The same purification step was used for the isolation of CPs from the vegetable oils.The concentration range for SCCPs was <10–389 ng/g lipid weight (lw, mean 36 ng/g lw for the oils and 28 ng/g lw for the fish) and that for MCCPs was <20–543 ng/g lw (mean 55 ng/g lw for the oils and 59 ng/g lw for the fish). There was found a high variability in concentrations of CPs influenced by area of origin.

A simplified screening method for short- and medium-chain chlorinated paraffins in food by gas chromatography-low resolution mass spectrometry

This study evaluates the performance of a simplified screening method for short- and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively) based on gas chromatography-electron capture negative ionization/mass spectrometry (GC-ECNI/MS) analysis and chlorine content quantification. The response from different combinations of ‘indicator’ congener groups present in technical mixture standards were used within calibration calculations to test the hypothesis that ∑SCCPs and ∑MCCPs could be quantified with acceptable accuracy using only a subset of the commonly analysed C10 to C17 and Cl5 to Cl10 groups. Potential combinations were assessed with respect to calibration curve performance and accuracy of SCCP and MCCP analysis of spiked food samples (olive oil, salmon, pork sausage, breakfast cereal, cow's milk and lard). Based on these trials, a screening method which quantifies ∑SCCPs and ∑MCCPs using only congener groups with 6 and 8 chlorine atoms for each carbon chain length was proposed. Concentrations of SCCPs and MCCPs in triplicate analyses of spiked food samples calculated using the proposed screening method deviated by ≤ 25% for the vast majority of samples (maximum deviation 37%) from levels determined using all analysed congener groups. The mean trueness of the screening method as applied to each of the spiked food samples and lard samples from a previous European Union Reference Laboratory (EURL) interlaboratory study ranged from 65 to 110% for ∑SCCPs and 102 to 175% for ∑MCCPs. Relative standard deviations (RSDs) were ≤ 25% for all triplicate analyses and matrix specific LOQs ranged from 0.7 to 6 ng/g ww for ∑SCCPs and from 1.3 to 12 ng/g ww for ∑MCCPs. The proposed screening method has the potential to deliver substantial time savings in instrumental analysis and manual labour without greatly reducing the overall accuracy and sensitivity of SCCP and MCCP quantification.

Short- and Medium-Chain Chlorinated Paraffins in Foods from the Sixth Chinese Total Diet Study: Occurrences and Estimates of Dietary Intakes in South China.

Food consumption has been identified as a major pathway for human exposure to short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs), but evaluations of SCCP and MCCP intake from major dietary sources are limited. We used the sixth Chinese Total Diet Study to perform a comprehensive investigation of SCCPs and MCCPs in cereals, vegetables, potatoes, legumes, eggs, milk, meats, and aquatic foods from nine southern provinces. The geographical distribution of CP concentrations showed higher levels in Jiangsu, Hubei, and Zhejiang provinces. The CP concentrations in most animal-origin foods were higher than those in foods of plant origin. The total estimated daily intakes (EDIs) of SCCPs and MCCPs, with average values of 7.0 × 102 and 4.7 × 102 ng kg-1 day-1, respectively, were mostly contributed by cereals, vegetables, and meats. Risk assessment indicated the EDIs of CPs posed no significant risk to residents in South China.

Optimization and validation of an analytical method for the quantification of short- and medium-chained chlorinated paraffins in food by gas chromatography-mass spectrometry

This work describes the optimization and validation of an analytical method for the quantification of short- and medium-chained chlorinated paraffins (SCCPs and MCCPs, respectively) in a range of food matrices using gas chromatography-electron capture negative ionization-mass spectrometry (GC-ECNI/MS). A dispersive solid phase extraction (dSPE) method was optimized for fish, meat, oil, milk and whole-grain cereal followed by clean-up with concentrated sulfuric acid and acid silica. Fractionation using silica cartridges efficiently removed a number of potentially interfering halogenated compound classes from sample extracts while retaining 96% of ∑SCCPs and 99% of ∑MCCPs. Limits of quantification (LOQs) estimated for food samples ranged from 0.7 to 6.0 ng/g wet weight (ww) for ∑SCCPs and 1.3–12 ng/g ww for ∑MCCPs. The applicability of the optimized protocol was assessed in each of the described food matrices via repeated analysis (n = 3) of samples fortified with SCCP 55.5%Cl and MCCP 57%Cl technical mixtures at two concentration levels and spiked lard samples from a recent European Union Reference Laboratory (EURL) interlaboratory study on CPs in food. The EURL's accuracy criteria was met for both homologue groups in all food matrices with overall accuracy in the range of 76–130% for in-house spiked samples and 57–150% for the EURL lard analysis. Excellent precision was observed for most samples with relative standard deviation (RSD) between replicates (n = 3) ≤ 12% for ∑SCCPs and ≤17% for ∑MCCPs in all food matrices analysed. The selection of the internal standard was a significant factor in the accuracy of the method and highlights the strong need for more appropriate isotopically labelled CP standards.

GC-FID를 이용한 식품 중 유동파라핀 함량 분석

본 연구에서는 GC-FID를 이용하여 식품첨가물공전에 사용량이 정해져 있는 빵류, 캡슐류, 건조과실류 채소류 및 과실류 채소류 중 유동파라핀의 함량을 측정하였다. 시료에서 n-hexane으로 유동파라핀을 추출하고 <TEX>$KMnO_4$</TEX> 산화반응을 통해 추출물 중 불포화탄화수소의 극성을 증대시킨 다음 aluminium oxide를 충진한 SPE 카트리지로 정제하여 GC-FID로 측정하였다. 검출한계와 정량한계는 각각 10 mg/kg과 20 mg/kg으로 개별 n-alkane으로 정량하는 방법이 아닌 넓은 봉우리로 나타나는 유동파라핀의 면적의 합으로 정량하는 문헌들(15,17)의 값과 유사하게 나타났다. 유동파라핀은 빵류, 건조과실류 채소류 및 캡슐류에서 이형제 등으로 사용되고 있으나 최종 완제품에서 사용기준 이하로 검출되었고, 과실류 채소류에서 모두 불검출로 나타남에 따라 안전한 수준으로 관리되고 있음을 알 수 있었다. Liquid paraffin is a mixture of heavier alkanes derived from petroleum. It can be used as a lubricant in processing machinery, as a coating agent, or as a releasing agent. The purpose of this study was to analyze liquid paraffins in foods by using a gas chromatography-flame ionized detector (GC-FID). Liquid paraffin was extracted from the food samples using n-hexane. Non-polar aromatic or olefinic co-extractives were removed by alkaline permanganate oxidation followed by clean up on an aluminium oxide SPE cartridge before the GC-FID analysis. The results of recovery tests were 91.5-103.2%. Based on this optimized method, we investigated the amount of liquid paraffin in various food samples purchased from domestic markets. The levels of liquid paraffin in bread were <TEX>$95.5{\pm}156.0$</TEX> mg/kg (0.008%), those in capsules were <TEX>$40.2{\pm}54.5$</TEX> mg/kg (0.001%), and those in dried fruits and vegetables were <TEX>$3.0{\pm}18.1$</TEX> mg/kg (0.0001%). No liquid paraffin was detected in fresh fruits and vegetables. We propose that our method can be used to monitor and detect liquid paraffin in foods for food safety management.

A versatile splitless injection GC-FID method for the determination of mineral oil paraffins in vegetable oils and dried fruit

A splitless injection GC-FID method for determining mineral paraffins in food was set up. The method has been developed on vegetable oils and subsequently adjusted and applied to dried fruits, a food matrix not yet investigated from this point of view. The method avoids the saponification step foreseeing only a clean-up on silica gel SPE, and allows the quantification of mineral paraffins with a limit of quantification (LOQ) of 15 mg kg −1 and a detection limit (LOD) of 5 mg kg −1 in the oils. LOQ and LOD for the analysis of dried fruit samples are respectively 1.0 and 0.3 mg kg −1. Eighteen samples of dried fruit were analysed (apricots, plums, raisins, coconut, dates, mango, pineapple). Two samples of apricots showed high values of contamination, 23.0 and 28.2 mg kg −1 of mineral paraffins, while all the other samples contained less than 6.4 mg kg −1 of mineral paraffins and in four samples mineral paraffins were undetectable.

Determination of mineral oil paraffins in foods by on-line HPLC–GC–FID: lowered detection limit; contamination of sunflower seeds and oils

A method is described to lower the detection limit for mineral oil saturated hydrocarbons (MOSH) in foods as compared to the on-line HPLC–LC–GC–FID method described previously: samples are preseparated (enriched) by conventional liquid chromatography on activated silica gel and activated aluminum oxide. The silica gel retains up to 1 g of fat or oil, the aluminum oxide up to 2 mg n-alkanes of at least 24 carbon atoms, i.e. plant paraffins which may severely hinder the analysis of the mineral paraffins. The efficacy of the method is shown for an apple and sunflower oil. Oils extracted from manually harvested seeds grown in fields or gardens contained between 0.14 and 0.77 mg/kg MOSH. In the oils from seeds sampled in an oil mill, this value was increased to 3.3–9.3 mg/kg, indicating a contamination during harvest, transport and/or storage. Concentrations in commercial refined sunflower oils ranged between 2.7 and 32 mg/kg, averaging 11.2 mg/kg. Since deodorization removes a substantial part of the MOSH, this suggests a further contamination in the oil mill. The contamination affected all samples at a similar level, indicating that it occurs systematically by the presently used technology.

Activated aluminum oxide selectively retaining long chain n-alkanes: Part II. Integration into an on-line high performance liquid chromatography–liquid chromatography–gas chromatography–flame ionization detection method to remove plant paraffins for the determination of mineral paraffins in foods and environmental samples

Aluminum oxide activated by heating to 300–400 °C retains n-alkanes with more than about 20 carbon atoms, whereas iso-alkanes largely pass non-retained (with characteristics described in more detail in Part I). This property is useful for the analysis of mineral oil contamination of foods and other matrices: it enables the removal of plant n-alkanes, typically ranging from C 23 to C 33, when they disturb the analysis of mineral paraffins (usually almost exclusively consisting of iso-alkanes). An on-line HPLC–LC–GC–FID method is proposed in which a first silica gel HPLC column isolates the paraffins from the bulk of edible oils or extracts and is backflushed with dichloromethane. In a second separation step, a 10 cm × 2 mm i.d. column packed with activated aluminum oxide separates the long chain n-alkanes from the fraction of the iso-alkanes which is transferred to GC–FID by the on-column interface and the retention gap technique. The retained n-alkanes are removed by flushing with iso-octane.

A versatile method for the determination of normal paraffins in foods.

Abstractn‐Paraffins are wide‐spread in foods as a result of plant biosynthesis, food chain transfer, and food technology utilisation. A versatile and specific method of analysis of series in the range C14 to C33 is proposed. Extraction stage, cleaning procedure and final determination are examined at length to avoid interferences, mainly from lipidic material and from cyclic and branched hydrocarbons. The determination is carried out on saponified samples, after hexane extraction then column chromatography on a silica, Florisil and alumina three beds column, followed by a temperature programmed gas chromatographic separation of individual n‐paraffins. One part per million of each paraffin may be determined in any kind of biological sample or food. Standard deviation measured at this low level is better than 5 %.