Isabel Castanheira

Characterisation of nutrient profile of quinoa (Chenopodium quinoa), amaranth (Amaranthus caudatus), and purple corn (Zea mays L.) consumed in the North of Argentina: proximates, minerals and trace elements.

Quinoa, amaranth and purple corn are Andean cereals largely consumed in North of Argentina. Nutrient analysis with the purpose of inclusion in the Argentinean FCDB and e-search EuroFIR has become urgent matter. In this work proximate and mineral profile of Andean cereals cultivated in the North of Argentina were determined and compared with rice. Proximate analysis showed that Andean cereals have similar profile but significantly higher (p<0.05) than rice. Andean cereals are rich sources of iron, copper, manganese and zinc and better than rice. Phosphorus and magnesium quinoa content could contribute up to 55% of consumers DRI. Andean cereals and rice are poor sources of potassium. To guarantee the interchange of data among users and producers of FCDB component values were obtained in compliance with EuroFIR guidelines for compilation process. Present work provides necessary information to FCDB users who wish to have access to food reference analytical parameters.

Development of a Method To Study the Migration of Six Photoinitiators into Powdered Milk

The aim of the present work was to develop a rapid multimethod for the analysis of six photoinitiators (PIs) in powdered milk and to study the migration of these PIs from LDPE packaging into powdered milk. The optimized HPLC-DAD method showed high correlation coefficients (>0.9999) over a concentration range of 0.1-10.9 mg/L. The kinetics of migration of the photoinitiators from LDPE packaging into powdered milk were determined at different temperatures. The key parameters of migration phenomena (diffusion and partition coefficients) were determined. The diffusion coefficients at 5 degrees C ranged between 8.4 x 10(-12) (for ITX) and 5.1 x 10(-10) (for benzophenone) and those at 40 degrees C between 5.9 x 10(-10) (for ITX) and 6.1 x 10(-9) (for Irgacure 184). The diffusion coefficients of the six model migrants under study increased with temperature and showed a good Arrhenius relationship between 5 and 40 degrees C.

Study of the migration of photoinitiators used in printed food-packaging materials into food simulants.

Photoinitiators (PIs) are used as catalyzers for inks and lacquers that are cured with ultraviolet (UV) light, and they can contaminate foodstuffs by mass transference.The aim of the present paper is to study the migration of six photoinitiators (Irgacure 184, benzophenone, Irgacure 651, Irgacure 907, ITX, and EHA) into food simulants [distilled water, 3% acetic acid (w/v) in aqueous solution, 10, 20, 30, 60 and 95% ethanol (v/v) in aqueous solution]. Migration levels of the six PIs into different food simulants were compared after a 30 day contact period with the additivated plastic. A relationship between R (ratio between log K(o/w) and MW) and total migration was found for PIs with log K(o/w) < 5. Key parameters of migration processes were calculated according to a mathematical model based on Ficks second law. Diffusion (D) and partition coefficients were estimated and compared among different simulants, temperatures, and PIs to understand better the mechanisms of the migration process and the physicochemical properties that most influence this phenomenon. For instance, at 5 degrees C, in ethanol 95% (v/v), D ranged between 4.2 x 10(-11) cm/s for Irgacure 907 and 3.0 x 10(-9) cm/s for benzophenone.

Evaluation of the risk/benefit associated to the consumption of raw and cooked farmed meagre based on the bioaccessibility of selenium, eicosapentaenoic acid and docosahexaenoic acid, total mercury, and methylmercury determined by an in vitro digestion model.

The bioaccessibility of total lipids, EPA, DHA, Se, Hg, and MeHg in raw and cooked meagre (Argyrosomus regius) was studied by using an in vitro digestion method. A risk-benefit assessment of raw and cooked meagre on the basis of the bioaccessibility data was carried out. The bioaccessibility of total lipids was generally high in raw and cooked meagre with exception of grilled fish. For EPA and DHA, bioaccessibility percentages were low never surpassing the 50% in raw, boiled, and grilled meagre. The bioaccessibility percentage of Se was equal or higher than 82% (grilling treatment). Likewise, for Hg and MeHg, high bioaccessibility values were determined with exception of grilled meagre, displaying lower values of 54% and 64%, respectively. The risk-benefit probabilistic assessment brought about a recommendation of a maximum consumption of two weekly meals for boiled or roasted meagre and three weekly meals for grilled meagre.

Protein content and amino acids profile of pseudocereals

Quinoa (Chenopodium quinoa), amaranth (Amaranthus caudatus) and buckwheat (Fagopyrum esculentum) represent the main protein source in several diets, although these pseudocereals are not currently present in the FCDB nutrient profile information. The aim of this work is to characterise the AA profile of these pseudocereals and compare them with rice. Total protein content revealed to vary from 16.3g/100g (quinoa Salta) to 13.1g/100g (buckwheat) and lower values were found in rice samples (6.7g/100g). For pseudocereals the most abundant essential AA was leucine. Quinoa-Salta evidences the highest leucine content (1013mg/100g) and the minor methionine content (199mg/100g). Buckwheat was the cereal with the highest phenylalanine content (862mg/100g). Rice (Oryza sativa) presents the lowest content for all AA. Results showed pseudocereals as the best source of AA. EuroFIR guidelines where strictly followed and proved to be a crucial tool to guarantee data interchangeability and comparability.

The emerging farmed fish species meagre (Argyrosomus regius): How culinary treatment affects nutrients and contaminants concentration and associated benefit-risk balance

The effect of cooking methods (boiling, grilling, and roasting) on the proximate and mineral composition, contaminants concentration and fatty acids profile was evaluated aiming to understand the benefits and risks associated to the consumption of the emerging farmed fish meagre (Argyrosomus regius). All the treatments led to lower moisture content. After grilling and roasting, the SFA, MUFA and PUFA contents increased. There was no degradation of EPA and DHA during the culinary processes. Significant retention of minerals in grilled and roasted meagre samples was registered. For Pb and Cd there were no concentration differences between culinary treatments and regarding raw fish. Whereas As level was higher in grilled meagre, total Hg and Me-Hg values were augmented in grilled and roasted meagre. The consumption of meagre is advisable due to the low and healthy fat, high selenium and protein content. Grilling would be the best culinary treatment due to the retention of protein, EPA, DHA and minerals. But as the risk of ingestion of Me-Hg content also increases, based on the risk assessment, intake should not exceed two weekly meals, provided that no other important Me-Hg food source is present in the diet. Otherwise, even this maximum threshold should be lower.

EuroFIR quality approach for managing food composition data; where are we in 2014?

A EuroFIR quality management framework was developed to assure data quality of food composition data, incorporating several recommendations developed or improved during the EuroFIR projects. A flow chart of the compilation process with standard operating procedures to assure critical steps was the starting point. Recommendations for food description, component identification, value documentation, recipe calculation, quality evaluation of values, guidelines to assess analytical methods, document and data repositories and training opportunities were harmonized as elements of the quality framework. European food composition database organizations reached consensus on the EuroFIR quality framework and started implementation. Peer reviews of the European compiler organizations were organized to evaluate the quality framework, focusing on what was achieved and on improvements needed. The reviews demonstrated that European food database compilers have made good use of standards and guidelines produced by EuroFIR, as well as a common understanding that a quality framework is essential to assure food composition data quality.

A LC/UV/Vis method for determination of cyanocobalamin (VB12) in multivitamin dietary supplements with on-line sample clean-up

A HPLC-UV/Vis method using a two-column strategy with a switching valve for on-line sample clean-up was developed for the determination of cyanocobalamin (CN–Cbl/Vitamin B12) in multivitamin dietary supplement tablets. The method uses two columns: an Agilent Zorbax C8 (150 mm × 4.6 mm, 5 μm particle size) reversed-phase column and a Waters Symmetry C18 (150 mm × 4.6 mm, 5 μm particle size) reversed-phase column. Chromatographic separation was achieved using a programmed gradient mobile phase consisting of (A) 0.1% formic acid in water and (B) 0.1% formic acid in acetonitrile. Because of the low levels of Vitamin B12 in the samples, large injection volumes, and thus much interfering material, must be used to exceed the limit of quantitation (LOQ) by UV detection. A switching valve was used to divert most of these early eluting interfering materials to waste, effecting on-line sample clean-up without excessive sample preparation steps. The recovery of CN–Cbl in the method was 99.5% and the LOQ was 10 ng per injection. The method was successfully applied to the analysis of the NIST SRM 3280 multivitamin/multimineral dietary supplement tablet. The method is specific, precise, and accurate for the intended use. Compared to off-line sample clean-up procedures, it offers the advantage of being easier, more economical, and less time-consuming.

Experimental approaches for the estimation of uncertainty in analysis of trace inorganic contaminants in foodstuffs by ICP-MS

Total Diet Studies to estimate dietary exposure to food contaminants need to evaluate laboratory measurements data variance. In this process it is critical that data from analytical methods are reliable to correctly scrutinize and compare values over time and between countries. In Europe it is widely recognized that the evaluation of measurement uncertainty is an important parameter when assessing the sources of analytical data variability. Two approaches are considered to estimate uncertainty in analytical measurement. Arsenic, Lead, Chromium and Cadmium, content in several food matrix determined by Inductively Coupled Mass Spectrometry (ICP-MS) microwave digestion assisted, are used as examples. The aim of the present research work is to compare both approaches accepted by Eurolab and GUM: Mathematical modeling to assess uncertainty components based on a classical model (bottom up) and an empirical method (top down), based on either experimental data obtained from a single laboratory validation data or inter-laboratory data from Proficiency Testing schemes. Relative expanded uncertainty calculated by both approaches agree when U (%) <20%. These values are concordant with RSDR reported in collaborative studies of EN 15763 (2009), which were assumed as target uncertainty. The top down approach described is simple and easy to use when compared with the mathematical modeling approach providing considerable benefits to those who assess data produced by several laboratories.

Optimizing UPLC isocyanate determination through a Taguchi experimental design approach

The development of a chromatographic procedure for an ultra‐performance liquid chromatography can be a very time‐consuming task, as the general approach for finding the appropriate operating conditions has been a trial‐and‐error process. The present study reports a novel approach in the field of ultra‐performance liquid chromatography by using statistical experimental design based on Taguchis method, which allows a complete separation of nine isocyanates present in a complex matrix. The resolution between two adjacent peaks was considered as a quality characteristic and transformed to a Taguchi signal‐to‐noise ratio. An orthogonal array L9 (34) was selected to analyze the effect of four chromatographic factors, that is, proportion of solvent, percent triethylamine (v/v), temperature (°C), and flow (mL min−1), with three levels each. The joint analysis performed to the significant factors achieved in the eight analyses of variance allowed to identify two methods to conduct a complete separation of all peaks. Six isocyanates were separated with the first method, with all factors at the lowest level. The remaining three isocyanates were separated with the second method, with the proportion of solvent at the highest level and the other factors at the lowest level. The overall Taguchi experimental design identified the proportion of solvent and the flow rate as major chromatographic factors. Finally, confirmatory experiments were performed with samples prepared with six and three isocyanates, confirming the complete separation of all isocyanates in the study.