Citrate calcium

Calcium citrate is produced as an intermediate in the purification of citric acid (CeHgO , or 2-hydroxypropane-l,2,3-tricarboxylic acid). A broth of citric acid is produced by the fermentation of sugar using a strain of Aspergillusniger mould. Suspended solids are removed by filtration. The solution is reacted with slaked lime to precipitate calcium citrate, which is separated by filtration. 

The calcium citrate is stirred in dilute sulfuric acid to regenerate citric acid, the calcium being precipitated as the sulfate, which is removed by filtration. Citric acid is then crystallised from the solution [31.13]. 

The slaked lime should be of food-grade quality (e.g., [31.30] and Table 31.2). 

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Lime-Sulfuric. Recovery of citric acid by calcium salt precipitation is shown in Figure 3. Although the chemistry is straightforward, the engineering principles, separation techniques, and unit operations employed result in a complex commercial process. The fermentation broth, which has been separated from the insoluble biomass, is treated with a calcium hydroxide (lime) slurry to precipitate calcium citrate. After sufficient reaction time, the calcium citrate slurry is filtered and the filter cake washed free of soluble impurities. The clean calcium citrate cake is reslurried and acidified with sulfuric acid, converting the calcium citrate to soluble citric acid and insoluble calcium sulfate. Both the calcium citrate and calcium sulfate reactions are generally performed in agitated reaction vessels made of 316 stainless steel and filtered on commercially available filtration equipment. 

Tentative Evaluation of the Health Aspects of Citric Acid, Sodium Citrate, Potassium Citrate, Calcium Citrate, Triethyl Citrate, Isopropyl Citrate, and Stearyl Citrate as Food Ingredients, PB280 954, National Technical Information Service, Springfield, Va., 1977. 

For a given slurry, the maximum filtration rate is determined by the minimum cake thickness which can be removed—the thinner the cake, the less the flow resistance and the higher the rate. The minimum thickness is about 6 mm (0.25 in) for relatively rigid or cohesive cakes of materials such as mineral concentrates or coarse precipitates like gypsum or calcium citrate. Sohds that form friable cakes composed of less cohesive materials such as salts or coal will usually require a cake thickness of 13 mm (0.5 in) or more. Filter cakes composed of fine precipitates such as pigments and magnesium hydroxide, which often produce cakes that crack or adhere to the medium, usually need a thickness of at least 10 mm (0.38 in). 

The citric acid obtained from fermentation is removed from the culture by precipitation. The precipitation is formed by the addition of Ca(OH)2 200 gl , at 70 °C. The pH of solution is adjusted to 7.2. Tri-calcium citrate tetrahydrate is collected by filtration. The tricalcium citrate as filter cake is dissolved in H2S04 at 60 °C with 0.1% excess, the solid retained is CaS04 and the free citric acid is obtained. The free concentration of citric acid is determined with an enzymatic kit available from Merck. GC/HPLC is recommended for high accuracy of any research work.5... 

B. Dinkelaker, Rdmheld, V., and H. Mar.schner, Citric acid excretion and precipitation of calcium citrate in the rhizosphere of white lupin (Lupinus aihus L.). Plant. Cell Environ. /2 285 (1989). 

Lactate 60 mg elemental calcium per 300 mg tablet ° Calcium citrate and gluconate do not require an acidic... 

Calcium citrate should not be administered with aluminum-containing compounds. Concomitant administration may increase systemic bioavailability of aluminum and predispose to toxicity... 

Calcium carbonate should be taken with food to maximize absorption. Elderly patients or patients receiving proton pump inhibitors or H2-receptor antagonists may have added difficulty absorbing calcium supplements because of reduced stomach acidity. Better absorption may occur in this setting with calcium citrate because an acid environment is not needed for absorption it may be taken with or without food. 

Calcium carbonate is the salt of choice because it contains the highest concentration of elemental calcium (40%) and is the least expensive (Table 3-3). It should be ingested with meals to enhance absorption from increased acid secretion. Calcium citrate absorption is acid independent and need not be taken with meals. Because the fraction of calcium absorbed decreases with increasing dose, maximum single doses of600 mg or less of elemental calcium are recommended. 

Calcium citrate, molecular formula, 6 638t Calcium citrate tetrahydrate molecular formula, 6 638t solubility in water, 6 649t Calcium cyanamide, 4 535, 548-549 8 157 17 270-271 manufacture, 8 161... 

E 333 Calcium citrates (i) Monocalcium citrate (ii) Dicalcium citrate (iii) Tricalcium citrate... 

Traditionally, citric acid is recovered from fermentation broth via a Ume and sulfuric acid process. In this process, filtered fermentation broth is treated with lime to precipitate calcium citrate. This precipitate is washed and acidified with sulfuric acid to convert the calcium citrate to solid calcium sulfate (gypsum) and... 

The development and maintenance of healthy bone depends in part on an adequate supply of dietary calcium. Although phosphate is absolutely required for the mineralization of bone, it is abundant in the diet. If one gets enongh to eat, one gets enough phosphate. The same is not necessarily trne for calcinm and many people snpplement their diet with a preparation of calcium, frequently calcinm glnconate or calcium citrate. More follows below about the chemistry of bone when we get to a consideration of calcium. 

Calcium carbonate 20 Calcium Chloride 20 Calcium Citrate 20 Calcium gluconate 20 Caltrate 600 20 Candesartan 20 Capoten 21 Capozde 73 Capsaidn 21 Captopril 21, 73 Cara te 62 Catbamazepine 21... 

The Health Benefits of Calcium Citrate Malate A Review of the Supporting Science... 

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