Bioavailability of nutrients in rats fed on edible seaweeds,Nori (Porphyra tenera) and Wakame (Undaria pinnatifida), as a source of dietary fibre

A comparative study of the influence of two edible seaweeds, Nori (Porphyra tenera) and Wakame (Undaria pinnatifida), on dietary nutritive utilization was performed. Male adult Wistar rats were fed, for 2 weeks, diets containing Nori, Wakame or cellulose as source of dietary fibre. All diets contained similar amounts of dietary fibre (5%), protein (14%) and ash (5%). Intake, body weight gain, food efficiency (weight gain/food intake), apparent digestibility and retention coefficients for protein, fat, and minerals (calcium, iron, magnesium, zinc, sodium, and potassium) were evaluated. The addition of Wakame or Nori did not affect the gain in body weight of rats or food efficiency. Fresh and dry stool weights were higher in rats fed seaweeds than in the control group. Seaweed-fed animals showed significantly lower apparent digestibilities of protein and fat but absorbed nitrogen was more effectively used by animals. Apparent digestibility and retention coefficients for calcium, magnesium, zinc, iron, sodium and potassium were lower for seaweed-fed rats, and showed lower values for Wakame than Nori. The seaweeds could be a good source of dietary fibre in diet but they may modify digestibility of dietary protein and minerals.     

克雷伯氏菌固定化技术发酵生产1,3-丙二醇

通过对4种常见的包埋材料固定化克雷伯氏菌发酵生产1,3-丙二醇的研究发现,海藻酸钙固定化无论在制备难易还是在发酵强度上都有很大优势,并进一步确定了海藻酸钙固定化的最优条件:海藻酸钠质量浓度6%,CaCl2质量浓度4%,交联时间4 h。相对于游离发酵,固定化发酵1,3-丙二醇终浓度提高了7.4%,发酵强度达到了1.04 g/(L.h)。此外,固定化克雷伯氏菌还能用于1,3-丙二醇半连续发酵。     

Yields, Proximate Composition and Mineral Content of Finfish and Shellfish

Yields of edible flesh, proximate composition, and mineral content were determined in two samplings of six finfish and four shellfish from the Chesapeake Bay region. Although there was considerable variation, most species have high protein (above 20%), low fat (less than 5%) and are relatively good sources of macrominerals, including calcium, phosphorus, magnesium and potassium. The ratio of sodium to potassium ranged from 1:4 to 1:15. These species, particularly the shellfish, are excellent sources of the trace elements, including copper, iron, zinc and manganese. Minerals are very high in certain shellfish.     

Content of mineral substances in the internal organs of rats on intravenous feeding

The experiments on rats receiving a complete intravenous nutrition (group 1) during 15 days showed that the concentration of natrium, magnesium and iron was increased in the liver and decreased in the spleen as compared to that in controls given normal feeding (group 2). The content of zink and copper (mg%) was significantly lowered in both the organs of rats in group 1. The growth of the liver and spleen mass during parenteral feeding led to a significant rise in the content of natrium, potassium, magnesium, iron, zink and manganese in the whole liver tissue of group 1 rats, while the content of calcium and copper was similar in both groups of animals. The content of natrium, potassium, magnesium, iron and zink in the whole spleen tissue was significantly higher in group 1 rats, while the content of calcium, copper and manganese was similar in both groups of rats. A correlation was revealed between the content of iron and copper in the liver tissue (r = +0.87) and the levels of natrium and magnesium it the spleen tissue (r = +0.78) of group 1 rats. In group 2 rats a correlation was recorded between the content of calcium and manganese in the liver tissue an the levels of natrium and calcium in the spleen (r = +0.85 and +0.86, respectively).     

电感耦合等离子体质谱法同时测定马鹿皮中9种元素

目的建立微波消解-电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法同时测定马鹿皮中钠、锰、镁、钾、钙、铁、硒、铜和锌9种元素的含量的方法。方法样品经硝酸-过氧化氢微波消解后,通过在线加入内标溶液校正,以72Ge为内标,采用ICP-MS测定马鹿皮中钠、锰、镁、钾、钙、铁、硒、铜和锌9种元素的含量。结果 9种元素线性良好,相关系数为0.9995~1.0000;钠、锰、镁、钾、钙、铁、硒、铜和锌的检出限分别为4、0.007、0.2、1、1、0.3、0.004、0.009、0.05 mg/kg;9种元素的回收率在86%~116%之间;相对标准偏差(relative standard deviation,RSD)≤7.2%(n=6)。结论该方法灵敏度高、稳定性好,可以满足马鹿皮中钠、锰、镁、钾、钙、铁、硒、铜和锌的测定。     

Effects of germination on the chemical composition of Glycine and Phaseolus beans

The effects of germination on total protein and amino acids, and phytic acid of beans of Glycine max L, Glycine hispida L, Phaseolus radiatus L and Phaseolus angularis L were studied. The increase in total crude protein content was > 21% for Glycine beans and 8–15% for Phaseolus beans. There was a marked increase in the total essential amino acids of Glycine max (76%) and Phaseolus radiatus (52%). A smaller increase was observed for Phaseolus angularis (25%) and Glycine hispida (3%). The phytic acid contents of the beans were drastically reduced (< 0.2%), mainly due to leaching into the soak water. Total ash content showed a decrease, too, also due to leaching; the loss of potassium was very high whereas losses of the divalent metals, calcium, iron and magnesium, were only moderate, probably because of the ability of divalent cations to bind to protein to form proteincation-phytate complexes and also because divalent salts of phytic acid are insoluble at moderate to high pHs.     

Effect of production environment, genotype and process on the mineral content of native bitter potato cultivars converted into white chuño

BACKGROUND: Variables and interaction effects affecting the mineral concentration of Andean bitter potatoes converted into so‐called white chuño are unknown. We report on the effect of three contrasting production environments (E) on the dry matter (DM), zinc, iron, calcium, potassium, magnesium, phosphorus and sodium concentration of four potato native bitter genotypes (G) processed (P) into two different ‘types’ of white chuño. RESULTS: The DM content and iron, calcium, magnesium and sodium concentration of white chuño are significantly dependent on E, G, P, and E × G × P interaction (predominantly at P < 0.01). In particular, the DM content and calcium concentration are influenced by all variables and possible interaction effects. The zinc and potassium concentration are not significantly dependent on E × G, G × P or E × G × P interaction effects, while the phosphorus concentration is not significantly affected by the G × P or E × G × P interaction effect. Zinc, phosphorus and magnesium concentrations decrease in the ranges of 48.3–81.5%, 61.2–73.0% and 62.0–89.7% respectively. The decrease in potassium is particularly severe, with 122‐ to 330‐fold losses. Iron and calcium increase by 11.2–45.6% and 74.5–714.9% respectively. CONCLUSION: E, G, P, and various interaction effects influence the mineral concentration of traditionally processed tubers. We speculate that mineral losses are caused by leaching, while increases of iron and calcium are a likely result of absorption. Copyright © 2012 Society of Chemical Industry     

Effect of dietary potassium percent for lactating dairy cows.

Three groups of Holstein cows (four cows per group) past the peak of lactation were fed dietary potassium as percent of dry matter as follows: .45% for 20 days to all groups; .45, .55, and .66% to the respective groups for 12 wk; and .66% to all groups for 19 days. Dietary potassium had no significant effect on milk fat and solids-not-fat contents of milk, milk production, or milk and blood serum cations (potassium, sodium, magnesium, calcium). However, body weights were affected. Symptoms common in potassium deficiency were not apparent. Average daily milk production, feed intake, and body weight gains for the 12 wk in kilograms were: 21.9, 15.8, and 15.7; 23.4, 16.4, and 54.5; and 22.8, 19.9, and 92.9 for the .45, .55, and .66% rations. When .66% potassium was fed to groups previously fed .45 and .55% potassium, feed intake increased by 3.6 kg and 1.3 kg but increased only .2 kg in the group previously fed .66%.     

Effect of Fermentation on Iron, Zinc, and Calcium Availability from Iron-fortified Dairy Products

ABSTRACT: Iron, zinc, and calcium dialyzability and ascorbic acid (AA) concentrations were determined in milk, acidified milk, or yogurt fortified with ferrous sulfate (FS) or iron bis-glycinate (FBG) with or without AA addition in a 4:1 AA:Fe molar ratio. Milk fermentation or acidification caused an increase in iron availability from both iron sources. Highest availability values were obtained for fermented products with added AA (18-fold increase compared to milk). AA oxidation during fermentation was minor. However, at 14 d of cold storage, AA degradation was close to 50% in FS-fortified yogurt and 35% in FBG-fortified yogurt. Nevertheless, iron dialyzability remained constant. Lactic acidification and fermentation also increased Zn availability, but Ca dialyzability was hardly increased by either treatment. AA addition did not modify Zn or Ca availability.     

Improving the sensory and nutritional value of gluten-free bread

Bakery products, especially breads, are important part of everyday diet. Home-made breads are all the more crucial on the gluten-free diet, as commercially available breads without gluten are often unattractive. The study presents the recipe, nutritional characteristics (fat, protein, calcium, magnesium, sodium, potassium, copper, iron, zinc, manganese), costs and consumer acceptance of four easy to make home-made gluten-free breads. Partial substitution of bread-mix based on corn and rice (control bread) with teff flour, amaranth flour or quinoa flour significantly changed the content of the most of analysed nutrients, while their price was comparable. The highest nutritional benefits were found for protein, magnesium, potassium, calcium, zinc, iron and manganese in bread with teff and for magnesium, potassium, zinc and manganese in bread with amaranth. The highest consumer acceptance of people on gluten-free diet was noticed for breads with quinoa and teff.     

Support materials for yeast immobilization affect the concentration of metal ions in the fermentation medium

Hydrogels are potential absorbers of ions present in the medium, but they can also release some cations (e.g. calcium in calcium alginates). Polyelectrolytes such as alginic acid and poly(acrylic acid) strongly bind polyvalent metal ions. In this paper, the impact of some materials used for the immobilization of yeast, in particular the concentration of certain ions, especially those that play a significant role in the process of fermentation such as calcium, magnesium, zinc and manganese, was assessed. The support for the immobilization of yeast (calcium alginate and polyacrylate) significantly affected the concentration of metal ions in a model solution. Calcium alginate decreased the concentration of Mg²⁺, Zn²⁺ and Mn²⁺ in the solution by about 10–25%, and greatly increased the Ca²⁺ concentration. Polyacrylate, while swelling, decreased the concentration of cations present by up to 50%. Based on the results in this work, no supplementation of wort with divalent metal salts is advised, since it may lead to a stronger cross‐linking of polyelectrolytes used, and consequently result in a slower fermentation. Similarly, the relatively high concentration of calcium ions, caused by ion exchange, did not appear to affect the fermentation process. Copyright © 2013 The Institute of Brewing & Distilling     

Metal content of United Kingdom and overseas lager beers

Results are presented for the levels of sodium, potassium, calcium, magnesium, iron, copper, zinc, lead and arsenic in 144 lager samples. The average and range of each of the metals, in mg/litre, are as follows: sodium 58(15–170), potassium 362(253–680), calcium 46(10–135), magnesium 82(34–162), iron 0.12(0.04–0.44), copper 0.11(0.01–0.41), zinc 0.06(0.01–0.46), lead all samples below 0.06, arsenic all samples below 0.02.     

Contents of macro and microelements in fresh and frozen dill (Anethum graveolens L.)

The level of ash and its alkalinity and the contents of potassium, sodium, magnesium, iron, phosphorus, zinc, copper, cadmium, and lead, were determined in green dill (leaves and whole plants, about 20 cm in height, harvest time). The two usable parts were frozen using variable pretreatments (blanching or no blanching) and different storage temperatures (−20 and −30 °C). Analyses were conducted after 0, 3, 6, 9, and 12 months of refrigerated storage. Fresh leaves contained more ash, magnesium, iron, phosphorus, zinc, cadmium and lead but less sodium and copper than whole plants, while the contents of potassium and calcium were similar. Blanching significantly reduced the level of ash and its alkalinity and of potassium, calcium, magnesium, phosphorus, zinc, copper, cadmium, and lead, both in the usable parts of the plant, and of sodium in whole plants and of iron in leaves. During the storage period, changes in the contents of the analysed constituents did not depend on the usable part or storage temperature, being statistically significant only for the contents of iron and copper in the two usable parts of frozen non-blanched dill.     

Effect of maturity stages on the content of ash components in raw,frozen and canned broad beans

The aim of the present work was to determine the level of ash, potassium, phosphorus, calcium, magnesium, iron, zinc, manganese, and copper in fresh and preserved broad bean seeds at the stage of milk-wax maturity. The experiments included two broad bean cultivars, four stages of seed maturity being differentiated in each. With the higher maturity stages, the contents of ash, potassium, phosphorus, calcium, and magnesium gradually increased in fresh matter of the two cultivars. The contents of zinc and copper showed a slight decreasing tendency, while the levels of iron and manganese varied. Frozen and canned broad bean seeds of milk-wax maturity, prepared for consumption, were a valuable source of mineral compounds. The more mature the seeds, the greater were the contents of potassium, phosphorus, calcium, magnesium, and manganese, and smaller less so for copper, while the levels of iron and zinc varied. Boiled frozen seeds contained more potassium, phosphorus, magnesium, zinc, manganese, and copper than canned products, no differences being found in the contents of calcium and iron. The dehulled seeds contained more phosphorus but less calcium than the intact ones.     

Lactic Fermentation of Non-Tannin and High-Tannin Cereals: Effects on In Vitro Estimation of Iron Availability and Phytate Hydrolysis

The effect on iron availability estimated in vitro and phytate hydrolysis was investigated in non-tannin and high-tannin cereals, lactic fermented as flour/water slurries or gruels. A natural starter culture initiated fermentation and addition of germinated flour and phytase in the fermentation process was tested. Lactic fermentation of nontannin cereals with added flour germinated sorghum seeds or wheat phytase increased iron solubility from about 4% up to 9 and 50%, respectively. Soaking flour in water before adding starter culture had a similar effect. The increase in soluble iron was strongly related to enzymatic deeradation of phytate (p<0.001). The reduction of inositol hexa- and pentaphosphates was about 50% with added germinated flour. Reduction was > 90% after soaking the flour prior to fermentation and almost complete with 50 mg phytase added. High-tannin cereals showed a minor increase in soluble iron after fermentation, ascribed to the inhibitory effect of tannins (both on iron solubility and on enzymatic hydrolysis of phytate). Lactic-fermented cereal foods have a potential in developing countries to improve iron nutrition.     

Calcium and Iron Distribution in Fortified Vacuum-impregnated Fruits Determined by Electron Dispersion X-ray Microanalysis

ABSTRACT: Fresh apple cylinders were vacuum-impregnated with aqueous solutions containing calcium and iron gluconates (calcium and iron concentration up to 114.7 g/L and 2.98 g/L respectively). The study demonstrated an important effect of Ca concentration on the response of apple tissue to vacuum impregnation (VI), increasing matrix elasticity, and diminishing external liquid net fluxes. None of the effect was attributed to Fe. The location and distribution of the cations were analyzed by Electron Dispersive X-ray Microanalysis (EDXMA). The results showed that they were located mainly in the intercellular spaces, and their distribution was homogeneous. A semiempirical relationship has been used to quantify the amount of incorporated calcium by EDXMA.     

Dietary exposure and health risk assessment for 11 minerals and trace elements in Yaoundé: the Cameroonian Total Diet Study

Dietary exposure to 11 elements was assessed by the Total Diet Study (TDS) method. Sixty-four pooled samples representing 96.5% of the diet in Yaoundé, Cameroon, were prepared as consumed before analysis. Consumption data were sourced from a household budget survey. Dietary exposures were compared with nutritional or health-based guidance values (HBGV) and to worldwide TDS results. Elevated prevalence of inadequate intake was estimated for calcium (71.6%), iron (89.7%), magnesium (31.8%), zinc (46.9%) and selenium (87.3%). The percentage of the study population exceeding the tolerable upper intake levels was estimated as <3.2% for calcium, iron, magnesium, zinc and cobalt; 19.1% of the population exceeded the HBGV for sodium. No exceedance of the HBGV for inorganic mercury was predicted in the population. The margin of exposure ranged from 0.91 to 25.0 for inorganic arsenic depending on the reference point. The “Fish” food group was the highest contributor to intake for calcium (65%), cobalt (32%) and selenium (96%). This group was the highest contributor to the exposure to total arsenic (71%) and organic mercury (96%). The “Cereals and cereal products” highly contributed to iron (26%), zinc (26%) and chromium (25%) intakes. The “Tubers and starches” highly contributed to magnesium (39%) and potassium (52%) intakes. This study highlights the dietary deficiency of some essential elements and a low dietary exposure to toxic elements in Yaoundé.     

Comparative study on nutrient and anti‐nutrient changes in Ikivunde and Inyange,two Burundian traditionally processed cassava products

A comparative study on nutrients and anti‐nutrients in Ikivunde and Inyange and a correlation of nutrients and anti‐nutrients with fermentation time during processing of both products were carried out. In Ikivunde, all nutrients and anti‐nutrients had high negative correlations with fermentation time, except for crude fibre, fats and calcium, which showed high positive correlations. In Inyange, all nutrients and anti‐nutrients were positively correlated with fermentation time, except for starch, ash, zinc, magnesium, calcium, glutamine and alanine. Analysis of variance showed that Ikivunde and Inyange differed significantly (P < 0.05) in reducing sugar, protein, ash, cyanide, phytic acid and tannin contents at various fermentation times. There were also significant differences (P < 0.05) between Ikivunde and Inyange in starch and fat contents at 48, 72, 96 and 120 h, while for crude fibre a significant difference was observed from 72 h until the end of fermentation. At the end of the fermentation period (120 h), Inyange had higher starch, protein, amino acid, reducing sugar, ash, iron, zinc, potassium, sodium, magnesium, fat, cyanide, phytic acid and tannin contents but lower crude fibre and calcium contents than Ikivunde. The results from this study showed that Inyange contains more nutrients and anti‐nutrients than Ikivunde. Copyright © 2006 Society of Chemical Industry     

火焰原子吸收光谱法测定Borojo果及其制品中的8种微量元素

Borojo果是一种天然的高钾低钠水果,是补充钾、钙和镁优良的食品来源。本文用火焰原子吸收光谱法测定Borojo果及其制品中铜、铁、镁、锌、锰、钾、钠、钙8种微量元素的含量,为Borojo果功效开发及深加工提供科学依据。样品经硝酸消解过夜,重复测定6次,计算精密度。方法前处理简单快速,重复性好,试剂用量小,加标回收率在94%-104%之间,相对标准偏差≤3.15%。Borojo冷冻干燥粉中8种微量元素分别是果肉的3倍左右。酶解浓缩粉中微量元素高于冷冻干燥粉,铜、锌分别高5和7倍;锰、镁、钾、钙、铁分别高1.08,1.16,1.22,1.12和1.23倍,钠高了55倍。Borojo果肉、冷冻干燥粉和酶解浓缩粉中的钾：钠比分别为2435：1,2870：1和63：1。8种微量元素比例同金丝枣、榴莲和干枣中相似,且比后者含有更多的镁。     

大豆馒头的研究

利用现代化微生物发酵技术,将筛选出的能发酵大豆粉的优良酵母菌株,采用老面发酵的方法对全脂大豆粉∶面粉=4∶6混合粉发酵做成馒头。此馒头色泽金黄、口感细腻、香气浓厚、营养丰富,同普通馒头相比蛋白质含量增加了6.69%、铁含量增加了0.013%、钙含量增加了0.052%、磷含量增加了0.132%。