Occurrence of biogenic amines in beers produced with malted organic Emmer wheat (Triticum dicoccum)

Because several groups of microorganisms are able to decarboxylate amino acids, the presence of biogenic amines (BA) can be seen as an index of the microbiological quality of the brewing process. BAs were quantified for the first time in the intermediate products and craft beers produced with malted organic Emmer wheat (Triticum dicoccum) in a small size brewery in order to assess the possible presence of critical control points related to biological hazard in the brewing process. BA levels in beers produced exclusively from malted organic Emmer wheat were between 15.4 and 25.2 mg l^–1 in the samples of light beer (Lt) and between 8.9 and 15.3 mg l^–1 in double malt beers (DM) ready for consumption (the beers stored for 90 days at 1–2°C). Cadaverine and tyramine were the main BAs in the Lt and DM beers, respectively. Increased concentrations of BAs seemed to be more related to the heat treatment of the processing product during mashing and wort boiling, rather than to the fermentation process. Much lower concentrations were found in finished beers obtained from 50% malted organic Emmer wheat and 50% malted barley (up to 3.2 mg l^–1) or from 30% malted Emmer wheat (up to 8.3 mg l^–1). Thus, Emmer wheat malt can be a useful alternative to wheat and spelt for the production of beer with a limited content of BA, if the processing technology is kept under control.     

Parameters affecting 5-hydroxymethylfurfural exposure from beer

5-Hydroxymethylfurfural (HMF) is generated during food and beverage heating processes and/or storage. Its daily intake, estimated as 4–10 mg day^?1, is several orders of magnitude higher than other process contaminants. Beer can be of relevance to the evaluation of HMF exposure; however, the information concerning its occurrence in different types of beer and during product storage is scarce. Therefore, the major goal of this work was to assess the amounts of HMF in different commercial beers, as well as the impact of storage, to deepen knowledge about the contribution of beer to HMF exposure. Blonde beers presented a mean content of 4.29 ± 1.05 mg L^?1, which was significantly lower (P ≤ 0.05) than those obtained for amber (6.84 ± 0.75 mg L^?1) and dark beers (6.99 ± 0.52 mg L^?1). Additionally, to study kinetic of HMF formation, fresh pilsner beers were stored at 30, 40 and 50°C during 40 days; a zero-order reaction was observed. The dependence of the rate constant on temperature was described by the Arrhenius equation and calculated activation energy was 101.85 kJ mol^?1. Storage can increase drastically HMF content, which means higher exposure for consumers. Thus, beer contribution to HMF exposure should not be neglected, since the intake of 1 L of beer entails a consumption of 4–7 mg of HMF or even more, depending on storage time and temperature.     

Development of a Green Chromatographic Method for Simultaneous Determination of Food Colorants

A green chromatographic method for the successful separation and determination of eight synthetic food colorants (Tartrazine E 102, Quinoline Yellow E 104, Sunset Yellow E 110, Carmoisine E 122, Ponceau 4R E 124, Allura Red E 129, Indigo Carmine E 132 and Brilliant Blue E 133) was developed. A C8 stationary phase was used and the mobile phase was a mixture of 50 mM phosphate buffer at pH 7 containing triton X-100 (0.25% v/v). The method was validated as regards its selectivity, linearity, precision, accuracy, limit of detection (LOD) and quantification (LOQ). LOD of colorants varied between 0.17 μg mL⁻¹ in Allura Red and 1.91 μg mL⁻¹ in Quinoline Yellow. In the case of LOQ, it was ranged from 0.52 in the Allura Red to 5.79 in the Quinoline Yellow. The method applicability was verified by the determination of colorants present in 22 samples. The 15 samples were only unicolor and the color concentration in these samples varied from 18.426 ± 0.100 to 610.390 ± 4.711 ppm. The method can be used successfully to the determination of binary and ternary color food and drug samples too. This method provides substantial green benefits without using organic solvents in extraction procedure and in both liquid and paper chromatographic methods.     

Magnetic Mixed Hemimicelles Solid-Phase Extraction of Three Food Colorants from Real Samples

Introducing a specific clean extraction procedure with a minimal matrices effect for food colorant determination is still a challengeable topic and highly recommended. Mixed hemimicelle solid-phase extraction method, based on cetyltrimethylammonium bromide-coated Fe₃O₄/SiO₂ nanoparticles as a novel, simple, and fast preconcentration method, was applied for preconcentration and fast isolation of three synthetic food colorants in foodstuff matrices prior to HPLC-UV-vis determination. The influence of different parameters on extraction efficiency such as surfactant amount, sample pH, time of extraction, desorption condition, and nanoparticles concentration was optimized. Under the optimized conditions, a preconcentration factor of 100 was achieved by extracting 10 mL sample. The limit of detection for the three synthetic food colorants including Tartrazine, Sunset yellow FCF, and Quinoline yellow is 2.50, 1.25, and 2.12 μg/L, respectively. The proposed method was applicable for extraction and preconcentration of three food colorants in various food samples with the food dye contents in the range of 13–105 μg/L.     

Beer Clarification Using Ceramic Tubular Membranes

In this work, laboratory-made green beers were produced using a commercial hopped malt extract and used to study their cross-flow microfiltration (CFMF) performance in a bench-top plant, appropriately designed and equipped with ceramic tubular membrane modules with nominal pore size of 0.4, 0.8, or 1.2 μm, under different values of the initial green beer turbidity (H?≡?0.7–61.9 European Brewery Convention (EBC) unit), feed superficial velocity (v _S?≡?2–6 m s^?1), and transmembrane pressure difference (TMPD?≡?0.97–4.73 bar) under constant temperature (~10 °C). Whatever the membrane pore size and rough beer turbidity, the minimum quasi-steady-state value of the overall membrane resistance \( \left({\mathrm{R}}_{\mathrm{T}}^{*}\right) \) was obtained at TMPD of 3 to 4 bar and v _S?=?6 m s^?1. The 0.8-μm pore membrane was selected for the loss in the permeate density, and color was limited, while the volumetric permeation flux was high enough. Then, it was used to assess a double logarithmic trend between the quasi-steady-state permeation flux (J*) and beer turbidity with a limiting flux of 63?±?6 L m^?2 h^?1 for H?>?21 EBC units. Precentrifuged beer feeding resulted in 2.7- to 4.1-fold increase in J* with respect to the above limiting flux, provided that the haze level of rough beer had been reduced to 1.0 or 0.7 EBC unit, respectively. The cake filtration fouling mechanism was identified as the main reason for flux decline by analyzing mathematically the time course of both the experimental permeate volume and permeation flux data. By operating with the aforementioned clarified green beers at TMPD of 3.73 bar, v _S of 6 m s^?1, and periodic CO₂ backflushing, the average permeation flux (300–385 L m^?2 h^?1) resulted to be from three to five times higher than that (80–100 L m^?2 h^?1) at 0–2 °C claimed by the three commercial CFMF processes currently available.     

Determination of the exposure parameters that maximise the concentrations of the anaesthetic/sedative eugenol in rainbow trout (Oncorhynchus mykiss) skin-on fillet tissue

Studies were conducted to determine the anaesthetic/sedative concentrations and durations that would maximise anaesthetic/sedative residue concentrations in rainbow trout (Oncorhynchus mykiss) skin-on fillet tissue. Rainbow trout (167–404 g) were exposed to 50 mg l^?1 AQUI-S^® 20E (10% active ingredient, eugenol) in 17°C freshwater for durations up to 1440 min, 100 and 250 mg l^?1 AQUI-S^® 20E for durations up to 240 min, and 500 and 1000 mg l^?1 AQUI-S^® 20E for durations up to 90 min. Fish exposed to 100 mg l^?1 AQUI-S^® 20E for durations of 30, 60, 120 and 240 min had the greatest eugenol concentrations in the fillet tissue, 50, 58, 54 and 62 µg g^?1, respectively. All other exposure concentrations and durations resulted in significantly lower eugenol concentrations, i.e. all < 39 µg g^?1.     

Influence of the range of molecular weight distribution of beer components on the intensity of palate fullness

The effect of the molecular weight distribution (MWD) of the beer components on the intensity of palate fullness was studied. The range of MWD for different types of maltodextrin and for nine commercial pilsner beers was determined using AF4/MALLS/RI. Sensory analysis (DIN 10952, DIN ISO 4120 and DIN 10963/ISO 8587) was carried out by a trained Deutsche Landwirtschafts-Gesellschaft, German Agriculture Society (DLG) tasting panel. The intensity of the palate fullness of a spiking trial (beer + maltodextrin) and the threshold concentration of the maltodextrins in beer was determined. The association between the ranges of MWD and the intensity of the palate fullness of the commercial pilsner beers was studied. AF4/MALLS/RI and sensory analysis were used to study the effect of variations of the brewing process on the range of MWD and the palate fullness of beer. The intensity of the palate fullness differed significantly (p < 0.0001) within commercial pilsner beers. Strong associations were found between the range of MWD of the commercial beers and intensity of the palate fullness (p < 0.05). The range of MWD of the commercial pilsner beers (3–13 kDa) corresponded to those found for maltodextrins with intermediated range of MWD (3.4–22.3 kDa). The threshold concentration was higher (p < 0.0001) for those maltodextrins with lower range of MWD (2.7–8.9 kDa). Beers produced with malted barley with Kolbach Index of 36 % exhibited a higher range of MWD (2.9–13 kDa) compared to those with Kolbach Index of 41 % (1.7–11.6 kDa). Slight differences in the palate fullness were perceived according to variations on the initial temperature of the mashing process among those beers produced using Kolbach Index of 36 %, whereas a great difference (p < 0.0001) was perceived using Kolbach Index of 41 %. The intensity of the palate fullness of the pilsner beer was influenced by the range of MWD of the beer components which would vary according to differences in the mashing process and of the quality of the malted barley.     

Lead excretion in milk of accidentally exposed dairy cattle

Lead (Pb) exposure in dairy cattle is associated with economic losses due to mortality and treatment costs, but with production animals there is also risk to the human food chain. The first objective of this study was to quantify the Pb concentration in milk from Pb-exposed cattle. The second objective was to correlate blood and milk Pb concentrations from individual cows. The third objective was long-term monitoring to determine the duration of milk contamination after exposure ceased. A dairy herd of more than 100 cows was accidentally exposed to Pb-contaminated feed. Milk and blood were collected for Pb analysis. Serial collection of milk samples continued for 2.5 years. The initial concentration of Pb in bulk tank milk was 0.0999 mg l^–1. The highest milk Pb concentration from an individual cow was 0.4657 mg l^–1 and the highest blood Pb concentration was 1.216 mg l^–1. One milk sample collected at the end of the study (day 922) contained 0.0117 mg Pb l^–1 of Pb. The calculated relationship between milk (y) and blood (x) Pb concentration was ln(y) = 3.4(x) – 2.21 (R² = 0.98).     

Why chlorate occurs in potable water and processed foods: a critical assessment and challenges faced by the food industry

Recently, reports have been published on the occurrence of chlorate mainly in fruits and vegetables. Chlorate is a by-product of chlorinating agents used to disinfect water, and can be expected to be found in varying concentrations in drinking water. Data on potable water taken at 39 sampling points across Europe showed chlorate to range from < 0.003 to 0.803 mg l^–1 with a mean of 0.145 mg l^–1. Chlorate, however, can also be used as a pesticide, but authorisation was withdrawn in the European Union (EU), resulting in a default maximum residue limit (MRL) for foods of 0.01 mg kg^–1. This default MRL has now led to significant problems in the EU, where routinely disinfected water, used in the preparation of food products such as vegetables or fruits, leaves chlorate residues in excess of the default MRL, and in strict legal terms renders the food unmarketable. Due to the paucity of data on the chlorate content of prepared foods in general, we collated chlorate data on more than 3400 samples of mainly prepared foods, including dairy products, meats, fruits, vegetables and different food ingredients/additives. In total, 50.5% of the food samples contained chlorate above 0.01 mg kg^–1, albeit not due to the use of chlorate as a pesticide but mainly due to the occurrence of chlorate as an unavoidable disinfectant by-product. A further entry point of chlorate into foods may be via additives/ingredients that may contain chlorate as a by-product of the manufacturing process (e.g. electrolysis). Of the positive samples in this study, 22.4% revealed chlorate above 0.1 mg kg^–1. In the absence of EU levels for chlorate in water, any future EU regulations must consider the already available WHO guideline value of 0.7 mg l^–1 in potable water, and the continued importance of the usage of oxyhalides for disinfection purposes.     

Effects of post-harvest stigmasterol treatment on quality-related parameters and antioxidant enzymes of green asparagus (Asparagus officinalis L.)

The effects of immersion of green asparagus spears in stigmasterol solution (0, 0.5 and 1.0 g l^?1, 15 min, 25°C) on weight loss, surface colour, enzyme activities and content of malondialdehyde, total phenol, lignin and chlorophyll were investigated during 40 days of storage at 4 ± 0.5°C. Of the concentrations tested, 0.5 g l^?1 treatment was most effective. Stigmasterol (0.5 g l^?1) treatment significantly reduced colour changes and losses of fresh weight and chlorophyll content. Superoxide dismutase (SOD) and catalase (CAT) activities were maintained higher in stigmasterol-treated (0.5 g l^?1) asparagus, whereas the activity of peroxidase (POD) was significantly reduced. Stigmasterol treatment (0.5 g l^?1) also significantly decreased the content of malondialdehyde (MDA) and increased total phenol content. Accumulation of lignin was positively correlated to activity of guaiacol-POD (r = 0.960, p < 0.01) in stigmasterol-treated (0.5 g l^?1) asparagus. The polyphenol oxidase (PPO) activity decreased and showed a significant negative correlation with the chroma L* value (r = –0.899, p < 0.01) in stigmasterol-treated (0.5 g l^?1) asparagus. It was concluded that stigmasterol treatment (0.5 g l^?1) could inhibit the senescence of green asparagus, and therefore prolong its shelf-life, maintaining the quality of post-harvest green asparagus.     

Content of biogenic amines and polyamines in beers from the Czech Republic

Altogether 114 samples of alcoholic and non‐alcoholic bottled beer produced in 28 breweries in the Czech Republic were monitored for levels of biogenic amines (BA) and polyamines (PA). The beers were analysed immediately after purchase and then at the end of the best‐before period (storage temperature 8 ± 1 °C). The concentrations of histamine, phenylethylamine and tryptamine in the studied samples were very low (mostly under 30 mg L^?1). The studied PA spermine and spermidine also occurred in small amounts. Nevertheless, the levels of tyramine, putrescine and cadaverine reached significant values, especially in alcoholic beers. In almost 25% of the tested samples of alcoholic beers (at the end of the best‐before period), the total amount of all the monitored BA and PA exceeded the ‘healthy’ level of 100 mg L^?1, which is considered toxicologically significant, especially in alcoholic beverages. Copyright © 2012 The Institute of Brewing & Distilling     

Consumer exposures to anthocyanins from colour additives,colouring foodstuffs and from natural occurrence in foods

Anthocyanins are responsible for the red/blue colour of grapes, currants, and other fruits and vegetables. They may also be extracted for use as colour additives (E163) or concentrated for use as colouring foods. Consumer exposures have been assessed using data on natural occurrence, use levels and frequencies from food manufacturers and European food consumption data. Intakes from natural occurrence can be up to 4 mg kg bw^?1 day^?1 at the mean and up to 17 mg kg bw^?1 day^?1 for children who are high level consumers of red/black berries and small fruits. High-level intakes for children from food colour and colouring food applications lie in the range 0.3–6.3 mg kg bw^?1 day^?1 and for adults at 0.6–2.8 mg kg bw^?1 day^?1. Exposures from food colour use and colouring foods separately or combined are therefore lower than those from natural occurrence in foods.     

Fluoride content of soft drinks,nectars, juices,juice drinks,concentrates, teas and infusions marketed in Portugal

A potentiometric method using a fluoride combination ion-selective electrode was validated and used to analyse 183 samples, including soft drinks, juices, nectars, juice drinks, concentrates, teas and infusions marketed in Portugal. The fluoride levels were higher in extract-based soft drinks, juice drinks and juice, with fluoride values of 0.86 ± 0.35, 0.40 ± 0.24 and 0.37 ± 0.11 mg l^?1, respectively. The lowest fluoride concentration was found in infusion samples (0.12 ± 0.01 mg l^?1), followed by teas and carbonated soft drinks with fluoride concentrations of 0.16 ± 0.12 and 0.18 ± 0.07 mg l^?1, respectively. Nectars, concentrates and juice-based drinks had similar fluoride concentrations of 0.33 ± 0.16, 0.29 ± 0.12 and 0.25 ± 0.14 mg l^?1, respectively. The fluoride concentrations in all these samples would only contribute intakes below the acceptable daily intake (ADI = 0.05 mg kg^?1 body weight day^?1), indicating that, individually, these beverages cannot induce fluoride toxicity in the population group of children.     

Heavy metals in vegetables sold in the local market in Jordan

Heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in various vegetables (cabbage, green onion, lettuce, parsley, rocket, spinach, carrot, onion, potato and cauliflower) from the market in Jordan were measured using inductively coupled plasma-mass spectrometry. As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged from 0.009–0.275 mg kg^?1 wet weight, 0.004–0.060 mg kg^?1, 0.003–0.401 mg kg^?1, 0.105–3.51 mg kg^?1, 0.15–1.15 mg kg^?1, 0.93–14.39 mg kg^?1, 0.044–0.702 mg kg^?1, 0.072–0.289 mg kg^?1 and 2.23–6.65 mg kg^?1, respectively. Parsley, followed by spinach, contained the highest concentration of heavy metals. Onion contained high levels of toxic heavy metals. The content of Cu in parsley and spinach and Pb in onion exceeded the Codex limits. However, the daily intake of heavy metals from the tested vegetables was lower than the maximum limits for allowable intake.     

Survey of deoxynivalenol and its conjugates deoxynivalenol-3-glucoside and 3-acetyl-deoxynivalenol in 374 beer samples

Beer is one of the most popular beverages worldwide. Malted cereal grains are among the basic ingredients and hence mycotoxin contamination might occur. Previous studies reported the presence of the Fusarium mycotoxins deoxynivalenol (DON) and 3-acetyl-deoxynivalenol (3ADON), as well as of the masked mycotoxin deoxynivalenol-3-glucoside (D3G) in beer. In the present survey, 374?beer samples from 38?countries with a focus on Austrian (156) and German (64) beers were analysed for the presence of D3G, DON and 3ADON. Beers were assigned to the following six categories: pale (217), wheat (46), dark (47), bock (20), nonalcoholic beers (19) and shandies (25). In total, 348 and 289 beers (93 and 77%, respectively) contained D3G and DON at the levels above the limit of detection, whereas 3ADON was not detected in any of the samples. Average concentrations of all beers were 6.9?µg?L^?1 for D3G and 8.4?µg?L^?1 in the case of DON. Nonalcoholic beers and shandies showed the lowest contaminations, 1.5 and 3.2?µg?L^?1 for D3G and 2.7 and 4.4?µg?L^?1 for DON, respectively. In bock beers characterised by a higher gravity, a significant trichothecene load of 14.8?µg?L^?1 D3G and 12.4?µg?L^?1 DON was found. The highest contamination (81?µg?L^?1 D3G, 89?µg?L^?1 DON) was detected in a pale beer from Austria, underlining the importance of this study for food safety. The molar D3G to DON ratio ranged between 0.11 and 1.25 and was 0.56 on average. Concluding, the average contamination of beer is not of toxicological concern for moderate beer drinkers. However, in the case of heavy beer drinkers, beer consumption may considerably contribute to the overall intake of DON, which might even lead to exceeding the maximum tolerable limits established for this Fusarium toxin.     

Comparison of the relative dissipation rates of endosulfan pesticide residues between oolong and green tea

The dissipation behaviour of endosulfan in dry made-tea leaves of oolong and green tea was compared to establish whether there was any difference in dissipation rates between the two teas. The dissipation of endosulfan in oolong and green tea corresponded with a first-order kinetics curve. The average half-life of endosulfan (n = 12) was 1.60 ± 0.44 days in green tea and 2.01 ± 0.55 days in oolong tea, showing a statistically significant difference, and indicating that the dissipation of the pesticide was significantly slower in oolong tea than that in green tea. Although the initial levels of residual endosulfan were lower in oolong tea, due to the slower dissipation rate, the residues 5–7 days after application were higher in oolong than in green tea. It is suggested that the minimum interval between endosulfan application and tea leaf harvesting is 7 days for green tea and 10 days for oolong tea in the case where the maximum residue limit of endosulfan in made-tea is fixed as 10 mg kg^?1.     

Determination of Amaranth in Beverage by Indirect Competitive Enzyme-linked Immunosorbent Assay (ELISA) Based on Anti-amaranth Monoclonal Antibody

Amaranth (E 123) is a member of azo dyes, and it is allowed to use in various foods. The acceptable maximum addition of amaranth is strictly fixed because of its potential risk to physical health. The objective of this study was to prepare a specific anti-amaranth monoclonal antibody and develop an indirect competitive ELISA for amaranth quantification analysis. The immunogen and the coating antigen were designed by introducing a carboxyl group into amaranth for the conjugation with carrier proteins. Based on the immunogen, the monoclonal antibody exhibits satisfactory performances and the proposed ELISA shows an IC₅₀ of 20.33 ng mL^?1. The limit of detection is as low as 3.35 ng mL^?1, and the linear standard curve of the method ranges from 3.0 to 243.0 ng mL^?1. Additionally, the antibody reflects minimal cross-reactivity (<1 %) with six related food dyes (erythrosine, ponceau 4R, allura red, tartrazine, sunset yellow FCF, and brilliant blue). The recoveries of amaranth spiked beverage samples are in the range of 85.8–100.7 % with low coefficient of variation values (<11.5 %). The data shows that the developed ELISA provides a simple, sensitive, specific, and accurate alternative for amaranth determination and monitoring. Furthermore, it is the first time that icELISA of amaranth is developed based on monoclonal antibodies.     

Occurrence of glyphosate in beer from the Latvian market

A sensitive LC-MS/MS method for the determination of glyphosate in beer has been developed, validated, and applied to analyse 100 beer samples from 24 different producers and distributors in Latvia. The selected samples represented most beer brands and varieties sold in local supermarkets. Different procedures for sample preparation and chromatographic separation were compared. The final version of the method consisted of solid phase extraction, chromatographic separation on aminopropyl stationary phase, and detection using tandem mass spectrometry. The concentration of glyphosate in beer varied from below the LOD of 0.2 μg kg^?1 up to 150 μg kg^?1, higher than previously reported. Significantly higher (p < 0.01) content of glyphosate was observed in beers that did not have the country of production disclosed on the label and were sold in local supermarkets by distributors from Latvia (1.8 μg kg^?1 median concentration in locally produced beer, 6.7 μg kg^?1 in beer of undisclosed origin).     

Detoxification of zearalenone and ochratoxin A by ozone and quality evaluation of ozonised corn

Zearalenone (ZEN) and ochratoxin A (OTA) are secondary toxic metabolites of fungi that can contaminate a wide range of food and feedstuff. In this study, the effects of ozone treatment on ZEN and OTA and the quality of ozonised corn are investigated. Ozone significantly affects ZEN and OTA solutions. ZEN was undetectable 5 s after being treated with 10 mg l^–1 ozone. However, OTA was resistant to ozonation with a degradation rate of 65.4% after 120 s of treatment. Moreover, ZEN and OTA solutions were difficult to degrade after being dried by a nitrogen stream. Results showed that ozone effectively degraded ZEN and OTA in corn. The degradation rates of ZEN and OTA in corn increased with ozone concentration and treatment time. The degradation of ZEN and OTA at different ozone concentrations appropriately conformed to first-order kinetics with an R² value > 0.8749. Furthermore, under the same conditions, corn with increased moisture content (MC) (19.6%) was more sensitive to ozone than corn with a low MC (14.1%). When treated with 100 mg l^–1 ozone for 180 min, ZEN and OTA in corn with 19.6% MC decreased by 90.7% and 70.7%, respectively. To evaluate the quality of ozonised corn, subsequent quality experiments were conducted using corn samples treated at different times with 100 mg l^–1 ozone. The MC of corn decreased after ozone treatment. The whiteness and yellowness of the corn increased and decreased with increasing time, respectively. The fatty acid value of the corn increased significantly (p ≤ 0.05) after 180 min of treatment. This study verified that ozone can effectively degrade ZEN and OTA in corn, but slightly affected corn quality.