Aluminium content of beers

 The aluminium (Al) concentration in different brands of beers packaged in Al cans and glass bottles was measured at the end of the shelf-life of the beer, by the Zeeman graphite furnace atomic absorption spectrophotometry (ZGFAAS) method. The results show that in all cases a brand of beer packaged in an Al can has a higher Al content than the same brand bottled in glass. The measurements of the Al concentration in some Al-canned beers throughout 12 months of storage show that a relatively small increase of the Al concentration in beers occurs throughout storage. All these results indicate that some Al is taken up by the beer in Al cans, presumably through the slight and slow dissolution of Al from the can wall, due to some defects in the protective lacquer layer. The evaluated daily intake of Al (0.256 mg) possible through the consumption of beer was practically negligible in relation to both the total daily dietary Al intake and the tolerable daily Al intake. Thus, beers are an insignificant source of dietary Al intake and it appears that the Al intake from beers (due to the low content of Al in beers and its low bioavailability) should not be a cause for concern with regard to Al toxicity for the human body. Received: 22 April 1996     

Detection of aluminum residue in fresh and stored canned beer

The United States produces about 200 million barrels of beer each year from which a large percentage is packaged into aluminum cans. It is important to identify the possible effects a particular foodstuff may induce on its package especially when it is being purchased and consumed nationwide on a regular basis. Very few studies have been done on aluminum can corrosion by beer. The purpose of this study was to compare aluminum levels in fresh, and stored, canned beer representative of U.S. quality draft. A 2 × 2 × 4 design was employed for two brands of beer, A and B, held at two different temperatures of 23 °C (room temperature) and 5 °C (refrigerated) over a period of 5 months. Room temperature beer was found to contain more aluminum (108μgl⁻¹) than refrigerated beer and brand A at room temperature had significantly more aluminum content (546μgl⁻¹) than brand B (414μgl⁻¹) at the end of the duration of storage period. Aluminum content changes from day 0 to day 150 were significant. From these results, it is shown that aluminum cans are corroded over time by canned beer. However this corrosion may be reduced through refrigeration.     

Selenium and Chromium Content of European Beers as Determined by AAS

The chromium and selenium content of 74 domestic and imported brands of beer were determined by atomic absorption spectrometry to evaluate the importance of beer as a dietary source of both elements. Chromium content of the selected beers ranged from less than 0.2 to 46 ng/ml, whereas selenium content varied from 0.2 to 15.2 ng/ml. The concentration levels were compared to literature data and the contribution of beer to the daily intake of both elements in Belgium was calculated. Chromium accounted for 5%, while selenium contribution was less than 1%. No definite correlation was found between chromium and selenium concentration and type of fermentation; also, chromium content was not related to selenium level.     

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.     

Aluminium content of soft drinks from aluminium cans

The aluminium (A1) content of soft drinks from A1 cans has been measured during 12 months of storage, by the graphite furnace atomic absorption spectrophotometry (GFAAS) method. The results show that the A1 content in all soft drinks increased during the whole storage time. This increase was a result of dissolution of A1 from the can wall due to the presence of aggressive ingredients in the soft drinks, mainly acids. The A1 content rose with increasing acid concentration and decreasing pH value of the soft drinks. The evaluated possible daily intake of A1 (0.8 mg) through consumption of these drinks was practically negligible in relation to total daily dietary Al intake, as well as to tolerable daily intake. Thus, soft drinks from A1 cans are an insignificant source of dietary A1 intake and it appears that the A1 intake from this source should not be a cause for concern in regard to A1 toxicity for the human body.

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Alnminiumgehalte in Erfrischungsgetränken aus Aluminiumdosen

Zusammenfassung Es wurde der Aluminiumgehalt in Erfrischungsgetränken aus Aluminiumdosen im Laufe von zwölf Monaten Lagerzeit durch GFAAS gemessen. Der Aluminiumgehalt nimmt in allen Proben im Laufe der erwähnten Lagerungszeit zu als Folge des Lösens von der inneren Dosenseite her durch das VorhandenScin von aggressiven Bestandteilen in Erfrischungsgetränken, vor allem durch Säuren. Der Aluminiumgehalt steigt mit der Säurekonzentration, d. h. mit der Abnahme des pH-Wertes, in Getränken. Die Tagesaufnahme von Aluminium (0,8 mg) durch den Konsum dieser Getränke ist allerdings bedeutungslos im Vergleich mit der Gesamttagesaufnahme von Aluminium durch die Nahrung sowie im Vergleich mit der zugelassenen Tagesaufnahme. Aus diesem Grunde stellen Erfrischungsgetränke aus Aluminiumdosen keine beachtenswerte Quelle der Aluminiumaufnahme dar.

     

A STUDY OF BEER STALING USING CHEMILUNINESCENCE ANALYSIS

The chemiluninescence (CL) analysis has been used to study beer staling. Several types of commercial Japanese beers were stored at 37°C and their CL development analysed at 60°C. The CL level in beer developed as the beer was stored to reach a maximum level and then decreased. The sum of the CL intensities for the first 1 hour showed a good relationship with staling degree as assessed in mean panel scores. It is postulated that the deterioration rates of beers might be assessed from the CL producing patterns in the fresh beers before storage. The presence of sulfite in beer depressed the CL production during its storage indicating that there is some contribution of sulfite to flavour stability due to its inhibitory effect on radical reactions in beer.     

Storage stability of pasteurized non‐filtered beer

The influence of pasteurization on non‐filtered beers was investigated during accelerated storage (40°C, 41 days). Two beers were produced from the same hopped wort, which was fermented with two different yeast strains. Half of the bottled beers were tunnel pasteurized resulting in four different beer samples. The pasteurization influenced the volatile profile of both fresh beers, but during storage the differences between the volatile profiles of pasteurized and non‐pasteurized beers disappeared. During the storage period, the pasteurized beers gave a lower rate of radical formation, as evaluated by electron spin resonance spectroscopy, indicating a better oxidative stability. The pasteurization had no effect on the levels of the pro‐oxidative metals iron and copper. Pasteurization slightly increased the protein content of the beers. SDS–PAGE analysis showed that the two beers had different protein profiles, which changed during storage; however, pasteurization of both beers did not affect their protein profiles. The level of thiols were lowered in one beer and raised in the other beer by pasteurization, but during storage the levels of thiols decreased at the same rate in all of the beers. It was concluded that pasteurization had a positive influence on the oxidative stability of non‐filtered beer. Copyright © 2013 The Institute of Brewing & Distilling     

Aging characteristics of different beer types

Eight commercial beers (3 lager beers, 2 dark ales and 3 high-alcoholic ales) were aged for one year under normal storage conditions, and the changes with time of flavour profile and the concentration of 15 volatile compounds were monitored. The compounds were chosen as markers to evaluate the importance of different reactions in the aging process of each beer type. The development of typical aging flavours during beer storage could be linked to the Maillard reaction, the formation of linear aldehydes, ester formation, ester degradation, acetal formation, etherification and the degradation of hop bitter compounds. A difference in the nature of aging flavours between lager and specialty beers was found and seemed to be mainly the result of an increased Maillard reaction in specialty beers. Based on the results, some practical strategies are proposed to improve the flavour stability, depending on the beer type.     

Ochratoxin A in domestic and imported beers in Belgium: occurrence and exposure assessment.

Determination of ochratoxin A (OTA) concentration was performed in commercial beer in Belgium using immunoaffinity column (OchraTest) clean-up and liquid chromatography. The procedure was validated and fulfilled the European Committee for Standardization's criteria. It offered a detection limit of 3 ng l(-1) and a quantification limit of 10 ng l(-1). Recovery experiments carried out with the spiked samples in the range 50-200 ng OTA l(-1) showed an overall average recovery rate of 97% (RSD = 2.8%). The validated method was applied to the analysis of 62 Belgian beers and 20 commercial beers imported from Denmark, France, Germany, Ireland, Mexico, The Netherlands and Scotland. None of these beers exceeded the previously suggested EU limit of 200 ng l(-1). However, OTA was detected in 60 Belgian beers and in all imported beers. The average levels of contamination were 33 ng l(-1) (RSD = 112%) and 32 ng l(-1) (RSD = 81%), respectively. The highest level found was 185 ng l(-1). On the basis of the established tolerable daily intake (TDI) of 5 ng kg(-1) body weight, accepted by the scientific committee on food of the EU, this study indicates that beer consumption in Belgium is not likely to contribute to more than a few per cent of the TDI based on the average consumption. This study also shows variability of the OTA contamination in beer with time. Thus, there is a potential risk of having highly contaminated batches from time to time. We therefore recommend to control further the OTA contamination in brewery products and to take precautionary measures during harvest, transport and storage of the raw materials to maintain the OTA intake at the lowest achievable level.     

Intake of ochratoxin A and deoxynivalenol through beer consumption in Belgium

Estimations of ochratoxin A (OTA) and 4-deoxynivalenol (DON) exposure of the Belgian population through beer consumption were made using the results of the recent Belgian food survey and the compiled data set of OTA and DON levels in conventionally and organically produced beers in 2003-05. For the consumers of organic beers, the daily intake of OTA was 0.86 (in 2003), 1.76 (in 2004) and 0.72 (in 2005) ng kg^-1 body weight (bw), considering the mean beer consumption (0.638 litres) and the average level of OTA in 2003, 2004 and 2005, respectively. Using the 97.5th percentile of beer consumption (1.972 litres), the corresponding OTA daily intakes were 2.65, 5.44 and 2.24 ng kg^-1 bw, which are close or above the tolerable daily intake (TDI) of 5 ng kg^-1 bw. For the consumers of conventional beers, the OTA intakes were low: 0.23, 0.23 and 0.11 ng kg^-1 bw day^-1 for the average beer consumption, in 2003, 2004 and 2005 against 0.72, 0.73 and 0.34 ng kg^-1 bw day^-1 when the 97.5th percentile level was considered. As for the DON intake, the estimates were quite low for both conventional and organic beer consumers when the provisional maximum TDI (PMTDI) of 1 µg kg^-1 bw was considered. Average consumption of organic beer led to daily intakes of 0.05 and 0.04 µg DON kg^-1 bw in 2003 and 2004, respectively, whilst for conventional beer, daily intakes were 0.07 and 0.05 µg DON kg^-1 bw. At the 97.5th percentile level of beer consumption, daily intakes of 0.15 and 0.13 µg kg^-1 bw were obtained for organic beers against 0.23 and 0.17 µg kg^-1 bw for conventional ones. The results showed that beer could be an important contributor to OTA exposure in Belgium, even though a declining trend seems to be apparent during the last year of monitoring. Therefore, efforts should be devoted to maintain the OTA levels as low as reasonably achievable, especially for organic beer.     

The Influence of Hopping on Formation of Carbonyl Compounds During Storage of Beer

Improving beer flavour stability is an important brewing goal. Pilot scale brewing trials (50 L) were performed that focused on the determination of the influence of hop pellet dosage and dosage timing on carbonyl compounds in stored beer. The reducing activity of experimental worts, beers and stored beers appeared to depend on the hop pellet dose. Brews with lower amounts of hop antioxidants showed an enhanced formation of carbonyl compounds over the course of beer storage. A correlation between DPPH reducing activity and the content of some carbonyls, including the important markers 2‐furfural and (E)‐2‐nonenal, was found. Fresh and aged beers hopped by different amounts of hop pellet doses were clearly distinguishable according to their carbonyl content using Cluster analysis. Results of the sensorial analysis corresponded to the analytical criteria values. Results of this study bring further evidence of the indispensable impact of hop antioxidants on the suppression of undesirable carbonyl compound formation in the course of beer staling, which can be significant in beers hopped by aroma hops. However, hop antioxidants are only one of many factors affecting beer staling.     

A preliminary study of the quality attributes of a cloudy wheat beer treated by flash pasteurization

Flash pasteurization (37 and 100 pasteurization units, PU) and conventional tunnel pasteurization (15 PU) processing of wheat beers were evaluated by examining their impacts on microorganisms, colour, colloidal haze and flavour stability during 84 days of storage at 20°C. The results revealed that the microbiological stability of 37 and 100 PU flash‐pasteurized beers was comparable with that of the 15 PU sample, and the development of both yeast and lactic acid bacteria was inhibited for 84 days of storage. The conventional tunnel‐pasteurized wheat beer resulted in a higher thermal load relative to the flash‐pasteurized samples based on the results of oxidative stability. These three pasteurized beers showed a similar decrease in haze intensity throughout the storage period. Meanwhile, flash‐pasteurized beers had better colour and colloidal haze stability than the tunnel‐pasteurized beer. It was also found by dynamic light scattering analysis that the temperature in the flash pasteurizer has the desired effect on the protein denaturation and particle size distribution. Therefore, flash pasteurization is a promising method to increase the shelf‐life of wheat beers instead of conventional tunnel pasteurization. Copyright © 2017 The Institute of Brewing & Distilling     

A preliminary study about the influence of high hydrostatic pressure processing on the physicochemical and sensorial properties of a cloudy wheat beer

High hydrostatic pressure (HHP) (400 MPa/15 min, 500 MPa/10 min, 600 MPa/5 min at 20 °C) and heat (60 °C/15 min) processing of wheat beers were evaluated by examining their impacts on microorganisms, colloidal haze, flavour, foam stability and shelf‐life prediction during 84 days of storage at 20 °C. The results obtained showed that the microbiological stability of HHP beers was comparable with heat‐treated samples, and the development of both aerobic bacteria and lactic acid bacteria was inhibited for 84 days of storage. The main parameters of the wheat beer, such as ethanol content, original extract, pH, bitterness and viscosity, were scarcely affected by either treatment compared with the control samples; however, heat pasteurization increased the colour value. Heat‐pasteurized beer resulted in an increase in the phenethyl alcohol concentration and a decrease in isoamyl acetate and ethyl acetate levels compared with the HHP samples. These treatments did not affect the amount of 4‐vinylguaiacol and 4‐vinylphenol in the beer. The HHP‐treated beers had higher colloidal haze and foam stability values than the heat‐pasteurized beers. Dynamic light scattering analysis showed that HHP treatments at 500 MPa/10 min resulted in smaller and more uniform particle sizes, which had a positive effect on beer haze stability during storage. Copyright © 2016 The Institute of Brewing & Distilling     

Lead in alcoholic beverages

Following the finding that blood lead concentrations in middle-aged men were positively associated with alcohol consumption, the Royal Commission on Environmental Pollution recommended that information on lead in alcoholic beverages be obtained. The results reported here were obtained in response to the Royal Commission's request. About 90% of canned and bottled beers contained less than or equal to 10 micrograms/l of lead, whereas nearly half the draught beers sampled contained greater than 10 micrograms/l and 4% contained greater than 100 micrograms/l. Opening the cans and bottles and pouring the contents into a glass had no significant effect on the lead concentration in the beer. All wines sampled directly from the bottle, that is without pouring, contained less than 250 micrograms/l of lead. However the lead concentration in some wines contained in lead-capped bottles increased significantly when the wine was poured from the bottle, in one instance the increment was 1890 micrograms/l. It is concluded that consumption of beer containing 50 micrograms/l of lead could make a substantial contribution to blood lead concentrations in man. Consumption of 1 l/day of wine containing 150 micrograms/l of lead could also make a major contribution to blood lead concentrations. Lead contamination of wine when it is poured from a bottle, which had been lead-capped, can sometimes greatly increase lead concentrations in the wine.     

Aluminium in food and daily dietary intake assessment from 15 food groups in Zhejiang Province,China

Aluminium was measured in 2580 samples of 15 food groups and dietary exposure was estimated. Samples were purchased and analysed during 2010 to 2014. High aluminium levels were found in jellyfish (mean 4862 mg/kg), laver (mean 455.2 mg/kg) and fried twisted cruller (mean 392.4 mg/kg). Dietary exposure to aluminium was estimated for Zhejiang residents. The average dietary exposure to aluminium via 15 food groups in Zhejiang Province was 1.15 mg/kg bw/week, which is below the provisional tolerable weekly intake of 2 mg/kg bw /week. Jellyfish is the main Al contributor, providing 37.6% of the daily intake via these 15 food groups. This study provided new information on aluminium levels and assessment of aluminium (Al) dietary exposure in Zhejiang Province of China.     

PLSR modelling of quality changes of lager and malt beer during storage

The aim of this research was to create mathematical models for describing the changes in beer properties by using two chemometric methods applied on the experimental data. The models are intended to be useful and trustworthy for calculating four beer properties based on three easily measured ones. For that purpose, lager and malt beer were packaged in glass bottles, while lager beer was also packaged in polyethylene terephthalate (PET). Samples were placed at room temperature in the dark for 6 months. Fifteen physical and chemical properties of the beer were measured before bottling, immediately after bottling and once per month for the next 6 months. Standard MEBAK and Analytica‐EBC methods of analysis were applied. During the 6 month period, seven properties changed >1%. Two partial least squares regression methods [polynomial regression, partial least squares regression with polynomial regression (PLSR‐PR) and response surface method (PLSR‐RSM)] were used for modelling the relationships amongst multivariate measurements. Models with high statistical significance were determined and two PLSR methods were compared. Both chemometric methods were found to be suitable for modelling physical and chemical changes in the beers during their commercial shelf‐life. The PLS‐RSM method was found to be the more precise and confident method in describing property changes for lager and malt beer in glass bottles, while the polynomial regression model was found to be better for the lager beer packaged in PET. The R² values determined for polynomial regression model were up to 0.939, while for the random surface method model the values were up to 1.000. Copyright © 2016 The Institute of Brewing & Distilling     

Prevalence and public health significance of aluminum residues in milk and some dairy products

Sixty random samples of bulk farm milk, market milk, locally manufactured processed cheese, and milk powder were collected to be analyzed for aluminum (Al) concentration using graphite furnace atomic absorption spectrometry (GFAAS). The results were compared with provisional acceptable permissible limits (PAPLs). The maximum estimated dietary intake (MEDI) of Al for the examined samples was calculated. In addition, an experimental study was conducted to determine the possible leaching of Al from cookware in milk during boiling. The obtained results showed that Al concentration in examined bulk farm milk samples was found to be negligible. In contrast, market milk revealed higher concentration, 65.0% of the examined samples were above the PAPLs. The results revealed significant difference of Al concentration among them. The Al levels in processed cheese wrapped in Al foil were significantly higher than those found in samples packed in glass containers with a significant difference of Al concentration between them. Also, 20% of the examined milk powder samples exceeded the PAPLs (0.01 to 0.4 mg/kg). The MEDI for Al in bulk farm milk, control market milk, market milk boiled in Al cookware, market milk boiled in stainless-steel cookware, processed cheese wrapped in Al foil, processed cheese packed in glass containers, and milk powder were calculated as 3.0%, 61.0%, 63.0%, 61.0%, 428.0%, 220.0%, and 166.0% from "PTDI," respectively. The results of the experimental study showed no marked significant differences of Al concentration between market milk (control group) and those boiled in Al cookware, as well as to those boiled in stainless-steel cookware. PRACTICAL APPLICATION: The results of the present study indicate that Al level in milk kept in Al containers and dairy products packed in Al foil is beyond the permissible limits, suggesting health hazard. Therefore, all milk cans should be constructed of stainless steel, prevent the entrance of tap water into milk, and the processed cheese should be packed in glass containers and not wrapped in Al foil. Leaching of Al increased to a significant percent more during storage than during boiling, so milk should be kept in stainless steel or glass containers in the refrigerator.     

Personality traits and bitterness perception influence the liking and intake of pale ale style beers

Bitterness is classically considered undesirable in foods and beverages. Yet, widespread commercial success of beers (like Bitters in the UK or IPAs in the US) indicate bitterness is desirable for some consumers. Here, we tested whether personality traits influence beer liking and intake. Under laboratory conditions, beer consumers (n = 109) rated liking and intensity of 2 pale ales and a lager, and intensity of two bitter solutions (quinine, Tetralone®). Participants also completed intake and personality questionnaires (Sensation Seeking, Sensitivity to Punishment and Reward, and Food Involvement). A liking ratio for each beer was calculated from each participant’s liking for that specific beer and their total liking for all beers. Participants were classified as weekly, monthly, or yearly pale ale consumers using intake data. Using intensity ratings, personality measures, and other parameters, hierarchical linear regression was used to predict liking ratios, and logistic regression was used to predict beer intake frequency. A significant interaction between Sensation Seeking and quinine bitterness (p = 0.03) was found for the liking ratio of a pale ale. The interaction revealed liking of the pale ale increased with Sensation Seeking but only if quinine bitterness was also high. Intake models showed increased odds of frequent pale ale intake with greater quinine bitterness and lower liking for lager beer. These data suggest liking and intake of pale ales is positively related to Sensation Seeking and bitter taste perception. Contrary to findings in other bitter foods and beverages, the high bitterness found in pale ales may be desirable for some consumers.     

The impact of sulphur dioxide and oxygen on the behaviour of 2-furaldehyde in beer: an industrial approach

2‐Furaldehyde is often used as an analytical indicator of beer flavour deterioration. Although 2‐furaldehyde itself has a flavour threshold far above levels generally present in beer, it can be used as a good marker of heat damage of beer. A reversed‐phase liquid chromatographic assay, using ultraviolet‐visible detection, was applied to investigate the behaviour of 2‐furaldehyde throughout the brewing process and during extended storage of beer. The impact of storage temperature, sulphur dioxide and oxygen content on the level of 2‐furaldehyde was studied. It was found that the concentration of 2‐furaldehyde markedly increases during wort boiling and is rapidly reduced by yeast during the first hours of fermentation, emphasising the yeast reducing capacity as a determinant factor for the 2‐furaldehyde content found in the final beer. The results obtained suggest that sulphur dioxide and oxygen content play a key role on the 2‐furaldehyde content in packaged beer. 2‐Furaldehyde increase during ageing is oxygen dependent and sulphur dioxide retards its development by possibly protecting beer against the occurrence of oxidative reactions.     

Composition and Daily Intakes of Some Trace Metals from Canned Beers in Nigeria

The concentration of a number of metals in a selection of brands of canned beers available in the Nigerian market was determined by atomic absorption spectrophotometry after HNO₃/H₂O₂ digestion. The results of the survey indicated that chromium, iron, nickel, cadmium and lead were present at concentrations above the permissible levels in drinking water, while the metals cobalt, zinc, aluminium and copper were present at levels below the permissible limits in drinking water. The metal content in the different beer types do not pose a risk to consumer health since the estimated metal daily intake per kg bodyweight is below the provisional tolerable intake of these metals as set by the World Health Organization.