Vegetation sodium concentration

The sodium concentration in vegetation varies greatly with plant age in general, increasing age leads to significant decreases in sodium content. In March, green rye accumulates 2000 mg kg DM of sodium, compared with 1000 mg kg at the end of April, and 500 mg kg in mid-June (Muller et al. 2001). 

Animal foodstuffs, with the exception of unsalted butter, naturally contain much more sodium than unsalted vegetable foodstuffs. Curd is relatively sodium-poor. Most of the sodium contained in milk leaves the curd with the whey. Cheese (7000-28000 mg kg DM of sodium) and sausage obtain their high sodium concentrations through NaCl-supplementation. As with breast milk, the sodium concentration of infant formulas is lower in sodium than cows milk, and covers the sodium requirement of babies (Harzer and Haschke 1989, Baranowski 2000). Fresh trout store only 4000 mg kg DM of sodium, while smoked (and salted) trout contains 18000mgkg f Marine fish deliver between 6000 and 29000 mg kg DM of sodium to the food chain. By comparison, salted herring contain huge amounts of sodium, perhaps 100 g Na or 250 g NaCl kg DM. 

Sulfur Dioxide and Sulfites. Sulfur dioxide [7446-09-5], SO2, sodium bisulfite [15181-46-1], NaHSO, and sodium metabisulfite [23134-05-6] ate effective against molds, bacteria, and certain strains of yeast. The wine industry represents the largest user of sulfites, because the compounds do not affect the yeast needed for fermentation. Other appHcations include dehydrated fmits and vegetables, fmit juices, symps and concentrates, and fresh shrimp (79). Sulfites ate destmctive to thiamin, and cannot be used in foods, such as certain baked goods, that ate important sources of this vitamin. 

Consider a lake with a smaU watershed in a forest ecosystem. The forest and vegetation can be considered as an acid concentrator. SO2, NO2, and acid aerosol are deposited on vegetation surfaces during dry periods and rainfalls they are washed to the soil floor by low-pH rainwater. Much of the acidity is neutralized by dissolving and mobilizing minerals in the soil. Aluminum, calcium, magnesium, sodium, and potassium are leached from the soil into surface waters. The ability of soils to tolerate acidic deposition is very dependent on the alkalinity of the soil. The soil structure in the... 

A homogenized sample of cereals, vegetables, fruits or potatoes (10-20 g) is extracted with an organic solvent such as acetone and methanol. After filtration, the extract is concentrated to about 20 mL by rotary evaporation below 40 °C. The residue is transferred with 5% sodium chloride (NaCl) aqueous solution and partitioned twice with n-hexane. The n-hexane extracts are dried with anhydrous sodium sulfate and subjected to a Florisil column chromatographic cleanup procedure. The eluate from the Horisil column is concentrated to dryness and the residue is dissolved in an appropriate amount of acetone for analysis by GC/NPD. ... 

Each sample was fortified with chlorpyrifos, as a reference standard, to determine the recovery during each extraction. Three portions of solvent were used, and the combined extract for each sample was dried with sodium sulfate. Analyses employed gas chromatography/flame photometric detection. Limits of detection for vegetation and animal tissues were 0.2 and 0.007 pg respectively. Recoveries from fortified samples were 82%. Diazoxon occurrence was infrequenf and at trace concentrations. 

Gaudette and Coatney [115] reported that primaquine phosphate was unstable when subjected to dry heat of 100 °C in the presence of sodium chloride for 24 h, when boiled in water for 24 h and when heated for 24 h at 100 or 200 °C in melted hydrogenated vegetable oil. These findings exclude the use of primaquine phosphate as a salt additive in cooking. Primaquine phosphate was isolated from the test preparations at alkaline pH by extraction into ethylene chloride, after which primaquine phosphate was returned to an aqueous phase by shaking with 0.1 N sulfuric acid the concentration of primaquine phosphate was then determined spectrophotometrically. The ultraviolet absorption curve of primaquine phosphate has maxima at 224, 266, 282, and 300 nm, and minima at 216, 250, 276, and 310 nm. A solution containing 10 yl/mL has an optical density of 0.375 at 282 nm optical densities were proportional to concentrations. 

Numerous accidental spills of sodium cyanide or potassium cyanide into rivers and streams have resulted in massive kills of fishes, amphibians, aquatic insects, and aquatic vegetation. Sources of poisonings were storage reservoirs of concentrated solutions, overturned rail tank cars, or discharge of substances generating free HCN in the water from hydrolysis or decomposition (Leduc... 

The concentration of residual chlorite ion in vegetables and eggs treated with sodium chlorite was determined by UV-ion chromatography (Suzuki et al. 1997). Sodium chlorite was extracted with water and cleaned-up using Cl 8 cartridge. The detection limit of sodium chlorite in vegetables and eggs was 1 mg/kg with recoveries of 90-100%. 

Vegetation in fish ponds may be controlled by treatment with white arsenic or commercial sodium arsenite if applied in concentrations of 1 to 2 parts As203 per million.3 Several applications each year may be needed. Under these conditions the natural fish foods are uninjured and small fish are not adversely affected. Hard waters require a somewhat higher concentration of arsenic. The latter disappears rapidly from the waters, probably owing to precipitation. 

Preservatives. Sulfur compounds, such as sulfur dioxide and sodium bisulfite, are used commercially to preserve the color of various food products, such as orange juice, dehydiated fruits and vegetables, such as apricots, carrots, peaches, pears, potatoes, and many odiers. Concentrated sulfur dioxide is used in wine-making to destroy certain bacteria. The color preservation of canned green beans and peas is enhanced by dipping the produce in a sulfite solution prior to canning. In 1986, some of these compounds and uses were put under closer regulation in the United States. 

A procedure for extracting BHA and BHT from vegetable oils has been reported by Phipps (98). The oil was dissolved in n-heptane and extracted with dimethylsulphoxide (DMSO). Extracts of DMSO were mixed with aqueous sodium chloride solution, and the SPA were back-extracted into petroleum ether with subsequent concentration and analysis. 

Tanaka et al. [ 16] have described a spectrophotometric method for the determination of nitrate in vegetable products. This procedure is based on the quantitative reaction of nitrate and 2-sec-butylphenol in sulfuric acid (5 + 7), and the subsequent extraction and measurement of the yellow complex formed in alkaline medium. The column reaction is sensitive and stable and absorbances measured at 418 nm obey Beer s law for concentrations of nitrate-nitrogen between 0.13 and 2.5 xg/ml. In this procedure, the vegetable matter is digested at 80 °C with a sodium hydroxide silver sulfate solution, concentrated sulfuric acid and 2-sec-butylphenol are added, and after 15 minutes of standing time the nitrated phenol is extracted with toluene. Finally, the toluene layer is back-extracted with aqueous sodium hydroxide and evaluated spectrophotometrically at 418 nm. The standard deviation of the whole procedure was 1.4%, and analytical recoveries ranged between 91 and 98%. 

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