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     

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     

Mercury and selenium content of Taiwanese seafood

Fish consumption is avid in Taiwan (and other Asian nations), but little is known about the mercury and selenium content in local seafood. This paper reports on total mercury, methylmercury and selenium levels from 14 commonly consumed seafood items obtained from Taichung, Taiwan. Mean total mercury concentrations varied nearly 100-fold across species. Fifty per cent of the marlins sampled and 35% of the sharks exceeded the 0.3?µg?g^?1 US Environmental Protection Agency (USEPA) guideline. Methylmercury comprised a majority of the total mercury in all species. In all species studied there was a molar excess of selenium over mercury. The rank order of mean selenium–mercury molar ratios was red tilapia (166.8)?>?abura (87.9)?>?river prawn (82.4)?>?whiteleg shrimp (64.2)?>?butterfish (44.6)?>?milkfish (37.0)?>?tuna (15.6)?>?grouper (13.9)?>?ayu (13.4)?>?coral hind (13.0)?>?weever (11.8)?>?saury (9.0)?>?shark (7.8)?>?marlin (4.2).     

改进的国标方法测定炒货类食品的可食部分与果壳中铝元素含量及其食用风险性探讨

目的 研究炒货食品可食部分与果壳中铝元素含量对人体摄入铝水平的影响,评估人体的食品安全风险暴露水平。方法采用HNO_3+H_2O_2+HF的酸消解体系进行微波消解前处理,运用电感耦合等离子体质谱法对炒货食品中可食部分与果壳的铝元素进行检测。通过对比每个样品的2部分数据,得出风险评估结果。结果 本方法在铝浓度为0～100μg/L范围内线性良好(r=0.9998),国家标准物质小麦、辽宁大米、茶叶的检测值都位于定值区间内,实际样品6次测定的相对标准偏差为3.45%,检出限为0.1 mg/kg,定量限为0.3 mg/kg。瓜子、花生、榛子样品的果壳部分铝含量高于可食部分,松子的果壳部分铝含量要低于可食部分,开心果的检测结果未収现明显觃律性。结论 为避克铝暴露量过高的风险,在炒货食用方式上,应注意减少与果壳的过多接触。     

Survey of histamine content in seafood on the market

Food poisoning involving histamine has occurred almost every year for 20 years in Tokyo, and is usually due to ingestion of fish with lean meat, such as sardine, mackerel, horse mackerel and so on. Therefore, we were investigated the levels of histamine and 4 non-volatile amines (tyramine, putrescine, cadaverine, spermidine) in 637 samples on the market. The water activity of samples in which histamine was detected at 5 mg/100 g and over was examined. Histamine, tyramine, putrescine, cadaverine and spermidine were detected in 66, 43, 26, 64 and 5 samples, and the detection ranges were 5-340, 5-51, 5-42, 5-180 and 5-8 mg/100 g, respectively. Most of the samples in which histamine was detected were semi-dried round and split sardine. Water activity of 24 samples of semi-dried round and split sardine in which histamine was detected was in the range of 0.68-0.96.     

食用植物油中叔丁基对苯二酚含量的测定

介绍了一种测定食用植物油中叔丁基对苯二酚(TBHQ)含量的方法.食用油样品中的TBHQ经80%乙醇提取、浓缩、定容后,注入气相色谱中用外标(ESTD)、面积归一化法测定,与标准曲线进行比较定量.该方法的线性相关系数R=0.99991,回收率为96.59%,相对标准偏差RSD为1.77%,分析结果比较理想.     

Mineral content of edible marine seaweeds

Mineral content was determined in several brown (Fucus vesiculosus, Laminaria digitata, Undaria pinnatifida) and red (Chondrus crispus, Porphyra tenera) edible marine sea vegetables. Seaweeds contained high proportions of ash (21.1–39.3%) and sulphate (1.3–5.9%). In brown algae, ash content (30.1–39.3%) was higher than in red algae (20.6–21.1%). Atomic absorption spectrophotometry of the ashes indicated that marine seaweeds contained higher amounts of both macrominerals (8.083–17,875 mg/100g; Na, K, Ca, Mg) and trace elements (5.1–15.2 mg/100 g; Fe, Zn, Mn, Cu), than those reported for edible land plants. Edible brown and red seaweeds could be used as a food supplement to help meet the recommended daily intake of some essential minerals and trace elements.     

Composition of flesh from different edible parts of cod

Cod fillet, trimmings from the fillet, and tissue recovered from the skeleton after filleting were assayed over a 12 month period for nitrogen, moisture, hydroxyproline and water holding capacity. No significant differences were found in nitrogen or moisture content. However, the mean hydroxyproline contents were significantly different in all three tissues. Water holding capacity was significantly less in tissues recovered from the skeleton than in fillet or fillet trimmings. A seasonal trend was observed in moisture and nitrogen content. Soluble and myofibrillar protein nitrogen and non-protein nitrogen were also measured on the three tissue types. No significant differences were found.     

Aluminium content of foods and diets

Literature data on the aluminium content of individual foods have been compiled, summarized and presented by food groups. The contribution of aluminium from food preparation and cooking utensils and from food additives is discussed. Literature data on the daily intake of aluminium are summarized, and the contribution of food groups to daily aluminium intake is estimated. The major sources of dietary aluminium include several with aluminium additives (grain products, processed cheese and salt) and several that are naturally high in aluminium (tea, herbs and spices). The aluminium that may migrate from aluminium utensils is probably not a major or consistent source of this element. Daily intakes of aluminium, as reported prior to 1980, were 18-36 mg per day. More recent data, which are probably more accurate, indicate intakes of 9 mg per day for teenage and adult females and 12-14 mg per day for teenage and adult males.     

Aluminium content of Spanish infant formula

Levels of aluminium in 82 different infant formulae from nine different manufacturers in Spain were determined by acid-microwave digestion and graphite furnace atomic absorption spectrophotometry. The influence of aluminium content in tap water in reconstituted powder formulae was examined and an estimate was made of the theoretical toxic aluminium intake in comparison with the provisional tolerable weekly intake (PTWI). Possible interactions between aluminium and certain essential trace elements added to infant formulations have been studied according to the type or main protein-based infant formula. In general, the infant formulae contained a higher aluminium content than that found in human milk, especially in the case of soya, preterm or hydrolysed casein-based formulae. Standard formulae gave lower aluminium intakes amounting to about 4% PTWI. Specialized and preterm formulae resulted in a moderate intake (11-12 and 8-10% PTWI, respectively) and soya formulae contributed the highest intake (15% PTWI). Aluminium exposure from drinking water used for powder formula reconstitution was not considered a potential risk. In accordance with the present state of knowledge about aluminium toxicity, it seems prudent to call for continued efforts to standardize routine quality control and reduce aluminium levels in infant formula as well as to keep the aluminium concentration under 300 μg l^-1 for all infant formulae, most specifically those formulae for premature and low birth neonates.     

Mercury content of some wild edible mushrooms

 The mercury (Hg) content of 112 samples of common, wild edible mushrooms was analysed by atomic absorption spectrometry. The average Hg content of all the samples was 1.72 mg/kg dry mass (DM) but the Hg concentrations found in different taxonomic groups (genera and species varied) remarkably. Although different sampling locations obviously have an effect on the Hg concentration of sporocarps, we found evidence for a Hg-accumulating capacity of some taxonomic groups. In addition to Agaricus and Macrolepiota, where the phenomenon of mercury accumulation has already been described, our results indicate high Hg levels in samples of Lycoperdon perlatum (average 2.94 mg/kg DM) and in Lepista species (average 3.02 mg/kg DM). These data confirm the need for greater attention to be given to Hg levels in wild common mushrooms, especially to Hg-accumulating species. Received: 20 February 1997     

Arsenic content of some edible mushroom species

The arsenic contents of 162 fruit body samples of 37 common edible mushroom taxa were analyzed. The samples were gathered from different habitats of Hungary (mainly from mountains) between 1984 and 1999. The arsenic content of the samples was measured by the inductively coupled plasma spectrometry method. Very low [lower than 0.05 mg/kg dry matter (DM)] concentrations were found in the samples of 13 taxa, while higher (or very high) contents were quantified in other common taxa (the highest arsenic content was recorded in the fruit body of Laccaria amethysthea at 146.9 mg/kg DM). The species of eight genera (Agaricus, Calvatia, Collybia, Laccaria, Langermannia, Lepista, Lycoperdon, Macrolepiota) belong to the so-called accumulating taxa, and this tendency is evident on all habitats. This arsenic accumulation capability is found in two orders of Basidiomycetes (Agaricales and Gasteromycetales), which is to say this phenomenon occurs in the families Agaricaceae, Tricholomataceae and Gasteromycetaceae. The accumulating taxa found all have a saprotrophic type of nutrition; arsenic accumulation is not detectable in xilophagous or in mycorrhizal species. The consumption of the accumulating species found has only a low toxicological risk for three reasons: the consumed fresh fruit bodies contain about a tenfold lower arsenic level than the dried ones, the majority of arsenic occurs not in poisonous inorganic, but in less dangerous (or not poisonous) organic forms, and the frequency of consumption is low.     

Mercury content of some wild edible mushrooms

 The mercury (Hg) content of 112 samples of common, wild edible mushrooms was analysed by atomic absorption spectrometry. The average Hg content of all the samples was 1.72 mg/kg dry mass (DM) but the Hg concentrations found in different taxonomic groups (genera and species varied) remarkably. Although different sampling locations obviously have an effect on the Hg concentration of sporocarps, we found evidence for a Hg-accumulating capacity of some taxonomic groups. In addition to Agaricus and Macrolepiota, where the phenomenon of mercury accumulation has already been described, our results indicate high Hg levels in samples of Lycoperdon perlatum (average 2.94 mg/kg DM) and in Lepista species (average 3.02 mg/kg DM). These data confirm the need for greater attention to be given to Hg levels in wild common mushrooms, especially to Hg-accumulating species. Received: 20 February 1997     

Aluminium content in foods with aluminium-containing food additives

The aluminium (Al) content of 105 samples, including bakery products made with baking powder, agricultural products and seafoods treated with alum, was investigated. The amounts of Al detected were as follows (limit of quantification: 0.01 mg/g): 0.01-0.37 mg/g in 26 of 57 bakery products, 0.22-0.57 mg/g in 3 of 6 powder mixes, 0.01-0.05 mg/g in all three agricultural products examined, 0.03-0.90 mg/g in 4 of 6 seafood samples, 0.01-0.03 mg/g in 3 of 11 samples of instant noodles, 0.04-0.14 mg/g in 3 of 4 samples of vermicelli, 0.01 mg/g in 1 of 16 soybean products, but none in soybeans. Amounts equivalent to the PTWI of a 16 kg infant were detected in two samples of bakery products, two samples of powder mixes and one sample of salted jellyfish, if each sample was taken once a week. These results suggest that certain foods, depending on the product and the intake, might exceed the PTWI of children, especially infants.     

Phenolic compound contents in edible parts of broccoli inflorescences after domestic cooking

Total flavonoid and individual hydroxycinnamoyl derivative (sinapic and caffeoyl‐quinic acid derivative) contents were evaluated in the edible portions of freshly harvested broccoli (cv Marathon inflorescences) before and after cooking and in the cooking water. High‐pressure boiling, low‐pressure boiling (conventional), steaming and microwaving were the four domestic cooking processes used in this work. The predominant sinapic acid derivatives were identified as 1,2,2′‐trisinapoylgentiobiose and 1,2′‐disinapoyl‐2‐feruloylgentiobiose. In addition 1,2‐diferuloylgentiobiose and 1‐sinapoyl‐2,2′‐diferuloylgentiobiose were also identified in broccoli inflorescences. The results showed large differences among the four treatments in their influence on flavonoid and hydroxycinnamoyl derivative contents in broccoli. Clear disadvantages were detected when broccoli was microwaved, namely high losses of flavonoids (97%), sinapic acid derivatives (74%) and caffeoyl‐quinic acid derivatives (87%). Conventional boiling led to a significant loss of flavonoids (66%) from fresh raw broccoli, while high‐pressure boiling caused considerable leaching (47%) of caffeoyl‐quinic acid derivatives into the cooking water. On the other hand, steaming had minimal effects, in terms of loss, on both flavonoid and hydroxycinnamoyl derivative contents. Therefore we can conclude that a greater quantity of phenolic compounds will be provided by consumption of steamed broccoli as compared with broccoli prepared by other cooking processes. Copyright © 2003 Society of Chemical Industry     

Dioxin concentrations in the edible parts of Japanese common squid and saury

We examined the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) in muscle and gut tissues from Japanese common squid and saury. These body parts are often eaten in Japan, so it is important to measure their dioxin concentrations and evaluate the risks to consumers. The toxic equivalent (TEQ) concentrations in the squid gut samples (1.0 to 14 pg-TEQ/g fresh weight, n=3) were 50-fold larger than those in the muscle tissues (0.020 to 0.22 pg-TEQ/g fresh weight, n = 3) taken from the same samples. By contrast, the TEQ concentrations in the saury gut samples (0.35 to 0.63 pg-TEQ/g fresh weight, n=3) were only 1.1- to 1.7-fold greater than those in the muscle tissues (0.33 to 0.37 pg-TEQ/g fresh weight, n= 3) from the same samples. The TEQ contents in the squid gut tissues ranged from 60 to 990 pg-TEQ/squid, accounting for about 95% of the total dioxin content of the edible parts of the samples. By contrast, the TEQ contents in the saury gut tissues ranged from 4.4 to 12 pg-TEQ/saury, accounting for less than 25% of the total dioxin content of the edible parts of the samples. These tissues showed comparable PCDD/PCDF-congener and dioxin-like PCB-isomer profiles in both species. The results indicate that squid gut tissues occasionally contain high levels of dioxins, and consumption of this foodstuff could potentially significantly increase the dietary intake of dioxins.