Spectrophotometric determination of single synthetic food colour in soft drinks using ion-pair formation and extraction

A simple spectrophotometric method has been developed for the determination of water-soluble synthetic food colours in soft drinks involving ion-pair formation with octadecyltrimethyl ammonium bromide at pH 5.6 and extraction of the ion-pair into n -butanol. The proposed method has been applied to determine amaranth, carmoisine, Green S, Orange G, Patent blue V, Ponceau 4R, Sunset yellow and tartrazine singly in soft drinks.
The optimum experimental conditions for the method were reported. The percent-age extraction for all the colours except Green S under the optimum conditions ranged from 98 to 100. The precision of the proposed method was in the range 1–2.4% at the level of 8.0 μg ml⁻¹ for the food colours.     

果酱和罐头中诱惑红的高效液相色谱测定法

建立果酱和罐头中诱惑红的高效液相色谱测定方法。样品中的诱惑红色素经提取后在酸性条件下被聚酰胺粉吸附,在碱性条件下解吸附,以甲醇和乙酸铵溶液为流动相,等度洗脱,紫外检测器检测,波长254nm,以相对保留时间定性,色谱峰面积定量。浓度与峰面积线性关系良好(r=0.9995),回收率83.0%~105.0%,相对标准偏差小于20%,最低检出浓度为2.5mg/kg;该方法操作简便、灵敏、准确,适用于果酱和罐头中诱惑红的检测。     

Trace metals in soft and durum wheat from Italy

A survey was carried out with the aim to assess the levels of some toxic (cadmium, lead) and essential (copper, zinc) trace metals in wheat grown in Italy. A total of 178 samples of soft wheat grain and 239 samples of durum wheat grain from all the Italian wheat-growing regions were pooled into 35 and 38 representative samples respectively. After dry ashing, cadmium and lead were determined by graphite furnace atomic absorption spectrometry (GFAAS), whereas copper and zinc were determined by flame atomic absorption spectrometry (FAAS). In soft wheat the mean and median contents of all samples were (on a dry weight basis) 40 and 33 mu g kg^-1 for cadmium, 16 and 14 mu g kg^-1 for lead, 3.4 and 3.2 mg kg^-1 for copper, 33 and 32 mg kg^-1 for zinc. Similar levels were found in durum wheat. In this latter case the mean and median were 42 and 39 mu g kg^-1 for cadmium, 15 and 14 mu g kg^-1 for lead, 3.5 and 3.2 mg kg^-1 for copper, 34 and 34 mg kg^-1 for zinc. Significant differences were detected for some metals in relation to geographical provenance and variety. The average intake of the four selected elements from wheat-based products was estimated for the Italian population.     

Assessment of human exposure to polybrominated diphenyl ethers in China via fish consumption and inhalation

This study examined human exposure to polybrominated diphenyl ethers (PBDEs) associated with fish consumption and inhalation in China. The median intake of sigma7 PBDEs via human milk was 48.2 ng/day for nursing infants (0-1 years old) (a range of 23.4-99.1 ng/day). For all other age groups, the median intake of sigma11 PBDEs via fish consumption was 1.7-12.9 ng/day with a range of 0.59-56.3 ng/g. Additionally, human exposure to PBDEs via inhalation was 2.7-9.2 ng/day (a range of 0.72-108 ng/day). The median total sigma11 PBDEs intakes for nursing infants (6874 and 7372 pg/ kg b.w./day for males and females, respectively) were much higher than other age groups (215-608 pg/kg b.w./ day). No significant difference in the total PBDEs intakes was found between males and females. Of the 11 PBDEs congeners, BDE-47 was predominant in the total intake for nursing infants with a mean contribution of 38%, whereas BDE-209 was the dominant congener of total intake for other age groups, varying from 44 to 61%. Currently, the PBDEs levels in Chinese consumer fish and the total intakes of PBDEs via fish consumption were at the lower end of the global range. Compared with similar studies in other countries, however, human exposure to PBDEs via inhalation in China was relatively high. Overall, estimated daily intake of total PBDEs in the Chinese population was far below the LOAEL. However, studies are needed to further understand the fate and impact of PBDEs as PBDE-containing products are still used widely in large quantities in China.     

Exposure to metals and arsenic from yellow and red tuna consumption

ABSTRACT

Tuna is one of the most frequently consumed fish and, as a predator, can biomagnify pollutants. Metal and other elements pollution is an important worldwide concern. Based on these considerations, the aim of this work was to investigate the occurrence of As, Cd, Cr, Ni, Hg and Pb in tuna coming from different FAO areas to evaluate human exposure. The analysis was performed on muscle tissues through a quadrupole inductively coupled mass spectrometry. One hundred thirty-one samples were analysed. One red tuna from the Adriatic Sea and 11 yellow tunas exceeded Pb maximum levels (MLs) with a concentration ranging 0.31–0.86 mg kg^?1; three red tunas from different Mediterranean sub-areas exceeded Hg MLs, with a concentration range 1.19 to 1.80 mg kg^?1. All the Hazard Indexes (HIs) were lower than one, indicating that only a negligible health hazard could derive from the ingestion of tuna, for both average and high consumers. The risk of carcinogenicity from Cr is still under debate at the concentrations detectable in food.     

Magnetic solid-phase extraction coupled with HPLC for the determination of Allura Red in food and beverage samples

A magnetic solid-phase extraction (MSPE) protocol prior to HPLC was developed for the extraction and determination of Allura Red in food samples. Magnetic nanoparticles were coated with tetraethylorthosilicate and 3-aminopropyltriethoxysilane and modified by graphene. Scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared spectrometry were used to characterise the graphene-functionalised sorbents; and the main parameters affecting the extraction such as sample volume, temperature, pH and time were investigated and established. Under optimised conditions, the pre-concentration factor of Allura Red was 200, and the calibration curve was linear at a concentration range of 5–1500 μg kg^?1. The LOD was 2 μg kg^?1, the limit of quantification was 7 μg kg^?1, and the relative standard deviation was 3.3%. The prepared MSPE procedure was simple and fast, and it was successfully applied for the determination of Allura Red in beverages, candy and jelly.     

BOPP瓶与PET瓶在热灌装果汁及饮料应用上之比较

以白柚果汁为例,分别热灌装于BOPP（biaxial oriented polypropyle与PET（polyethylene terehthalate)瓶内,藉分析贮藏35d于4℃、25℃及37℃之温度下样品之物理化学性质,探讨两种包材对于热罐装饮料品质影响。     

Occurrence of caffeine,saccharin, benzoic acid and sorbic acid in soft drinks and nectars in Portugal and subsequent exposure assessment

A reliable method for the determination of benzoic and sorbic acids, caffeine and saccharin in soft drink and nectars using high performance liquid chromatography and UV detection was validated. The chromatographic separation was achieved with a C18 column (250 × 4.6 mm) and one buffered mobile phase, KH₂PO₄ 0.02 M/ACN (90:10)/phosphoric acid at pH 4.2. The effluent was monitored at 220 nm.     

Human exposure to lead,cadmium and mercury through fish and seafood product consumption in Italy: a pilot evaluation

The presence of selected toxic heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg), was investigated in fish and seafood products, namely, blue mussel, carpet shell clam, European squid, veined squid, deep-water rose shrimp, red mullet, European seabass, gilthead seabream, Atlantic cod, European hake, Atlantic bluefin tuna and swordfish so as to assess their human exposure through diet. Metals were detected by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and hydride generation atomic absorption spectrometry (Hg-AAS). Measurements of Cd, Pb and Hg were performed by means of analytical methods validated in compliance with UNI CEI EN ISO/IEC 17025 [2005. General requirements for the competence of testing and calibration laboratories. Milano (Italy): UNI Ente Nazionale Italiano di Unificazione]. The exposure assessment was undertaken matching the levels of Cd, Pb and total Hg with consumption data related to fish and seafood products selected for this purpose. In order to establish human health implications, the estimated weekly intakes (EWIs) for Cd, Pb and Hg were compared with the standard tolerable weekly intakes (TWI) for Cd and provisional tolerable weekly intakes (PTWIs) for Pb and Hg stipulated by the European Food Safety Authority (EFSA) and the Food and Agriculture Organization/World Health Organization (FAO/WHO) Joint Expert Committee on Food Additives (JECFA). The found metal concentrations were largely below the maximum levels (MLs) established at the European Union level with the exception of Cd. This metal exceeded the MLs in squid, red mullet, European hake and Atlantic cod. Squid and blue mussel showed the highest Pb concentrations which accounted for 60% and 10% of the MLs, respectively. Highest Hg levels were found in predatory fish. The concentrations of Hg in swordfish, Atlantic bluefin tuna and red mullet accounted for 50%, 30% and 30% of the MLs, respectively. The EWIs for Cd, Pb and Hg related to the consumption of fish and seafood products by the median of the Italian total population accounted for 20%, 1.5% and 10% of the standard TWI for Cd as well as PTWIs for Pb and Hg, respectively. Furthermore, the EWIs estimated using consumption data concerning Italian consumers did not exceed the standard TWI and PTWIs, except for Cd at 95th percentile.     

Assessment of Slovak population exposure to cadmium from food

Exposure of the Slovak Republic population to cadmium from food and drinks was studied. Calculations were done by means of 1,66,312 food, plant and animal raw materials and drinks sampled within systematic inspection and monitoring of contaminants in 1990–2003. Exposure assessment of average inhabitants to cadmium from actual and model consumption patterns were calculated and compared with the provisional tolerable weekly intake (PTWI) value. Considering the model consumption, the exposure doses were assessed also for selected demographic groups. The assessed exposure of the population to cadmium has been persistently low with a moderately decreasing tendency especially for the past few years. The assessed real weekly exposure doses of cadmium from foodstuffs and beverages in the last 5 years while using the mean values and median values were 20–14.8% PTWI and 12.6–7.6% PTWI, respectively.     

Microfluidic chip based chemiluminescence detection of L-phenylalanine in pharmaceutical and soft drinks

A sensitive chemiluminescence (CL) method on chip coupled with microfluidic system has been reported for the determination of L-phenylalanine (L-PA). A microfluidic chip device with the detection chamber capable of fast sensing light emitted from the luminol and hydrogen peroxide CL reaction catalyzed by copper sulphate was fabricated for the determination of L-PA. The microfluidic chip was fabricated by a soft-lithographic procedure using polydimethyl siloxane (PDMS). The fabricated PDMS microfluidic chip had four inlet microchannels for introducing the sample, chemiluminescent reagent, Cu(II), and oxidant, and a 500 μm wide, 250 μm deep, and 82 mm long microchannel. The detection was based on the enhancement effect of L-PA on the CL signals of luminol–H₂O₂–Cu²⁺ system in an alkaline medium. The CL intensity of the system was enhanced linearly with the concentration of L-PA in the range of 1.5 × 10⁻⁹–1.2 × 10⁻⁷ mol L⁻¹. The limit of detection was found to be 2.4 × 10⁻¹⁰ mol L⁻¹ with the relative standard deviation of 1.8%. The presented method offers a simple, rapid and easy to handle analytical technique in terms of sensitivity, dynamic range and low detection limit for the determination of L-PA in diet soft drinks and pharmaceutical injection samples.     

Natural occurrence of fumonisin B2 in red wine from Italy

The potential risk of exposure to fumonisin B₂ (FB₂) in the grape-wine chain has recently been revealed after a report of Aspergillus niger in grapes and its ability to produce FB₂ and FB₄. The occurrence of these two fumonisins in wine was investigated by LC/MS/MS in 51 market samples (45 red, five white and one rosé wine) produced in various Italian regions. Nine samples of red wine were found to be contaminated by fumonisin B₂ at levels ranging from 0.4 to 2.4 ng/ml, while FB₄ was not detected in any of the tested samples. This is the first report on the natural occurrence of FB₂ in wine, indicating that, although at low levels, there is a potential risk of FB₂ exposure for the wine-consumer.     

Factors affecting the estimated probabilistic acute dietary exposure to captan from apple consumption

The effect of the number of pesticide residue values below the LOQ/LOD of analytical methods, the variability of residues in individual fruits, mass of fruit units and the number of bootstrap iterations was studied on the probabilistically estimated acute exposure of consumers. The 4720 daily apple consumption data and the results of 1239 apple sample analyses for captan residues, performed within the Hungarian monitoring programme between 2005 and 2011, were used in this study as model matrix. Up to about 95th percentile exposure (µg/(kg bw·day)), simply multiplying each residue in composite samples with each consumption value gave similar estimates to those obtained with the complex procedure taking also into account the mass of and residues in individual fruits. However, the exposure above the 95th percentile calculated with the complex procedure gradually increased with increasing percentile level compared to the simple procedure. Including the high number of non-detects reduced the estimated exposure, which was the highest when only the residues measured in treated fruits were taken into account. The number of bootstrap iterations between 100 and 10,000 did not significantly affect the calculated exposure. The 99.99th percentile exposure amounted to 17.9% of the acute reference dose of 300 µg/(kg bw·day) for women of childbearing age.     

Prediction of red wine colour and phenolic parameters from the analysis of its grape extract

Herein, the phenolic composition and colour attributes of red grapes extracts (obtained with a fast methodology) were correlated with those of their corresponding wines to predict the final quality properties of wines. The phenolic parameters were evaluated as total phenolic compounds (TPC), total anthocyanins (TA) and total condensed tannins (TCT), whereas the chromatic parameters were evaluated as colour intensity (CI), tonality (To), and the percentages of yellow, red and blue tones. All of them were determined by usual UV–Vis spectrophotometric methods. To get robust models, grapes of five red varieties were collected at three different ripening stages throughout the 2009 vintage. Good correlations between the results from grapes and wines were obtained, showing high regression coefficients and low prediction errors for TPC (R² = 0.929, RMSE = 5.99%), TA (R² = 0.953, RMSE = 7.23%) and CI (R² = 0.954, RMSE = 7.58), concluding that these wine phenolic properties can be predicted reliably from the extracts obtained with an optimised fast extraction method from grapes on the ripening controls along the maturity process.     

Improved method for the determination of benzene in soft drinks at sub-ppb levels

An automated, simple, and reproducible method based on isotope dilution headspace gas chromatography/mass spectrometry developed previously for the determination of benzene in soft drinks was further improved by adding sodium sulfate to samples, lowering the gas chromatography oven starting temperature to narrow benzene peak width, and increasing sample injection volume. This improved method had a lower detection limit (0.016 µg l^-1) and good repeatability, and was used in a follow-up survey to assess benzene levels in 139 samples of soft drink products. Benzene was detected in 67% of the 139 products tested. Compared with the previous survey, the average benzene concentrations in most products from this survey were lower, and only a few products had benzene at elevated levels.     

Solid‐phase extraction and spectrophotometric determination of Allura Red (E129) in foodstuff,soft drink,syrup and energy drink samples: a comparison study

Amberlite XAD‐7 and XAD‐8 resins were used as adsorbents for preconcentration and determination of Allura Red (AR) food dye in aqueous medium. The effects of pH, sample volume, sample and eluent flow rates on the extraction of AR were optimised. The determination of dye was performed at 506.0 nm using spectrophotometry. Interference effects of matrix ions and some dyes were also investigated under optimised conditions. The methods permitted low detection limits which were 1.2 and 0.6 μg L^?1 for XAD‐7 and XAD‐8, respectively. Adsorption behaviours were investigated by adsorption isotherms and zero charge pH experiments. Validations of the method were performed by determination of AR contents in some foodstuffs. AR contents of liquid samples were found between 58 and 440 μg mL^?1. AR concentrations of solid samples were between 416 and 432 μg g^?1. The XAD‐7 and XAD‐8 resins presented a fast and reliable potential to determine AR dye in real samples.     

Identification and quantification of Class IV caramels using capillary electrophoresis and its application to soft drinks

A capillary electrophoresis method was developed for the analysis of Class IV caramels using sodium carbonate buffer at pH 9·5. A relationship was established between the migration time of the coloured ‘caramel’ peak and the caramel's sulphur content. There was also a linear relationship between the concentration of caramel solids in water and the peak area of the ‘caramel’ peak in the range 0·1–10 g litre⁻¹. A range of soft drinks was analysed for caramel. Seven non-diet and 12 diet cola products had Class IV caramel of high-sulphur, high-nitrogen content at concentrations estimated to be between 0·57 and 0·82 g solids litre⁻¹. © Crown Copyright 1998.     

Determination of water-soluble vitamins in soft drinks and vitamin supplements using capillary electrophoresis

A method for the determination of six water-soluble vitamins based on capillary electrophoresis (CE) operated in micellar mode was developed. Thiamine hydrochloride (vitamin B1), riboflavin (vitamin B2), pyridoxine hydrochloride (vitamin B6), pantothenic acid (vitamin B5), nicotinamide (vitamin B3), and cobalamin (Vitamin B12) could be separated in a single run. All CE parameters such as buffer composition and operation temperature were optimized in order to achieve better separation. Relative standard deviations (RSDs) of the described method ranged from 1.08 to 3.68% (intra-day precision) and 1.26 to 3.35% (inter-day precision). The method was then used for measuring various soft drinks and vitamin supplements directly without any step of sample cleanup. The determination of niacin was successful for all samples tested, reaching recoveries near 100%. Riboflavin and pyridoxine were quantified successfully in some but not all samples. Therefore, an evaluation on a case-by-case basis is mandatory. When applicable, this method provides a fast, accurate, simple, and inexpensive way to quantify selected vitamins, and is therefore well suited for routine analysis in soft drink industry.