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Calcium Lactate
Calcium lactate is a white crystalline salt with formula , consisting of two lactate anions (CHOH) for each calcium cation . It forms several hydrates, the most common being the pentahydrate ·5. Calcium lactate is used in medicine, mainly to treat calcium deficiencies; and as a food additive with E number of E327. Some cheese crystals consist of calcium lactate. Properties The lactate ion is chiral, with two enantiomers, D (−,''R'') and L (+,''S''). The L isomer is the one normally synthesized and metabolized by living organisms, but some bacteria can produce the D form or convert the L to D. Thus calcium lactate also has D and L isomers, where all anions are of the same type. Some synthesis processes yield a mixture of the two in equal parts, resulting in the DL (racemic) salt. Both the L and the DL forms occur as crystals on the surface of aging Cheddar cheese.G.F. Tansman, P.S. Kindstedt, J.M. Hughes (2014): "Powder X-ray diffraction can differentiate between enantio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Efflorescent
In chemistry, efflorescence (Derived from the Latin verb 'efflorescere' roughly meaning 'to flower') is the migration of a salt to the surface of a porous material, where it forms a coating. The essential process involves the dissolving of an internally held salt in water or occasionally, in another solvent. The water, with the salt now held in solution, migrates to the surface, then evaporates, leaving a coating of the salt. In what has been described as "primary efflorescence", the water is the invader and the salt was already present internally, and a reverse process, where the salt is originally present externally and is then carried inside in solution, is referred to as "secondary efflorescence". Efflorescences can occur in natural and built environments. On porous construction materials it may present a cosmetic outer problem only (primary efflorescence causing staining), but can sometimes indicate internal structural weakness (migration/degradation of component materials ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheddar Cheese
Cheddar cheese (or simply cheddar) is a natural cheese that is relatively hard, off-white (or orange if colourings such as annatto are added), and sometimes sharp-tasting. It originates from the English village of Cheddar, Somerset, Cheddar in Somerset, South West England. Cheddar is produced all over the world, and ''cheddar cheese'' has no Protected designation of origin, Protected Designation of Origin (PDO). In 2007, the name West Country Farmhouse Cheddar was registered in the European Union and (after Brexit) the United Kingdom, defined as cheddar produced from local milk within Somerset, Dorset, Devon and Cornwall and manufactured using traditional methods. Protected Geographical Indication (PGI) was registered for Orkney Scottish Island Cheddar in 2013 in the EU, which also applies under UK law. Globally, the style and quality of cheeses labelled as cheddar varies greatly, with some processed cheeses packaged as "cheddar". Cheeses similar to Red Leicester are sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Citrate
Calcium citrate is the calcium salt of citric acid. It is commonly used as a food additive ( E333), usually as a preservative, but sometimes for flavor. In this sense, it is similar to sodium citrate. Calcium citrate is also found in some dietary calcium supplements (e.g. Citracal or Caltrate). Calcium makes up 24.1% of calcium citrate (anhydrous) and 21.1% of calcium citrate (tetrahydrate) by mass. The tetrahydrate occurs in nature as the mineral Earlandite. Chemical properties Calcium citrate is sparingly soluble in water. Needle-shaped crystals of tricalcium dicitrate tetrahydrate a3(C6H5O7)2(H2O)2�2H2O were obtained by hydrothermal synthesis. The crystal structure comprises a three-dimensional network in which eightfold coordinated Ca2+ cations are linked by citrate anions and hydrogen bonds between two non-coordinating crystal water molecules and two coordinating water molecules. Production Calcium citrate is an intermediate in the isolation of citric acid from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Veterinary Medicine
Veterinary medicine is the branch of medicine that deals with the prevention, management, medical diagnosis, diagnosis, and treatment of disease, disorder, and injury in non-human animals. The scope of veterinary medicine is wide, covering all animal species, both List of domesticated animals, domesticated and wildlife, wild, with a wide range of conditions that can affect different species. Veterinary medicine is widely practiced, both with and without professional supervision. Professional care is most often led by a veterinarian, veterinary physician (also known as a veterinarian, veterinary surgeon, or "vet"), but also by paraveterinary workers, such as veterinary nurses, veterinary technicians, and veterinary assistants. This can be augmented by other paraprofessionals with specific specialties, such as animal physiotherapy or dentistry, and species-relevant roles such as farriers. Veterinary science helps human health through the monitoring and control of Zoonosis, zoonoti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrate
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' may differ). This formula does not imply direct covalent bonding between hydrogen and oxygen atoms; for example, in , hydrogen is covalently bonded to carbon, not oxygen. While the 2:1 hydrogen-to-oxygen ratio is characteristic of many carbohydrates, exceptions exist. For instance, uronic acids and deoxy-sugars like fucose deviate from this precise stoichiometric definition. Conversely, some compounds conforming to this definition, such as formaldehyde and acetic acid, are not classified as carbohydrates. The term is predominantly used in biochemistry, functioning as a synonym for saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermentation
Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduced by donating their electrons to other organic molecules (cofactors, coenzymes, etc.). Fermentation is important in several areas of human society. Humans have used fermentation in the production and preservation of food for 13,000 years. It has been associated with health benefits, unique flavor profiles, and making products have better texture. Humans and their livestock also benefit from fermentation from the microbes in the gut that release end products that are subsequently used by the host for energy. Perhaps the most commonly known use for fermentation is at an industrial level to produce commodity chemicals, such as ethanol and lactate. Ethanol is used in a variety of alcoholic beverages (beers, wine, and spirits) while lactate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Hydroxide
Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca( OH)2. It is a colorless crystal or white powder and is produced when quicklime ( calcium oxide) is mixed with water. Annually, approximately 125 million tons of calcium hydroxide are produced worldwide. Calcium hydroxide has many names including hydrated lime, caustic lime, builders' lime, slaked lime, cal, and pickling lime. Calcium hydroxide is used in many applications, including food preparation, where it has been identified as E number E526. Limewater, also called milk of lime, is the common name for a saturated solution of calcium hydroxide. Solubility Calcium hydroxide is moderately soluble in water, as seen for many dihydroxides. Its solubility increases from 0.66 g/L at 100 °C to 1.89 g/L at 0 °C. Its solubility product ''K''sp of 5.02 at 25 °C, its dissociation in water is large enough that its solutions are basic according to the following ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Carbonate
Calcium carbonate is a chemical compound with the chemical formula . It is a common substance found in Rock (geology), rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skeletons and pearls. Materials containing much calcium carbonate or resembling it are described as calcareous. Calcium carbonate is the active ingredient in agricultural lime and is produced when calcium ions in hard water react with carbonate ions to form limescale. It has medical use as a calcium supplement or as an antacid, but excessive consumption can be hazardous and cause hypercalcemia and digestive issues. Chemistry Calcium carbonate shares the typical properties of other carbonates. Notably, it: *reacts with acids, releasing carbonic acid which quickly disintegrates into carbon dioxide and water: : *releases carbon dioxide upon heating, called a thermal decomposition reaction, or calcination (to above 840 °C in the case of ), t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word "base": '' Arrhenius bases'', '' Brønsted bases'', and '' Lewis bases''. All definitions agree that bases are substances that react with acid An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...s, as originally proposed by Guillaume-François Rouelle, G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form hydroxide ions OH−. These ions can react with Hydron (chemistry), hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction. A base was therefore a metal hydroxide such as NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weak Acid
Acid strength is the tendency of an acid, symbolised by the chemical formula , to dissociate into a proton, , and an anion, . The dissociation or ionization of a strong acid in solution is effectively complete, except in its most concentrated solutions. : Examples of strong acids are hydrochloric acid (), perchloric acid (), nitric acid () and sulfuric acid (). A weak acid is only partially dissociated, or is partly ionized in water with both the undissociated acid and its dissociation products being present, in solution, in equilibrium with each other. : Acetic acid () is an example of a weak acid. The strength of a weak acid is quantified by its acid dissociation constant, K_a value. The strength of a weak organic acid may depend on substituent effects. The strength of an inorganic acid is dependent on the oxidation state for the atom to which the proton may be attached. Acid strength is solvent-dependent. For example, hydrogen chloride is a strong acid in aqueous solu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Humidity
Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation (meteorology), precipitation, dew, or fog to be present. Humidity depends on the temperature and pressure of the system of interest. The same amount of water vapor results in higher relative humidity in cool air than warm air. A related parameter is the dew point. The amount of water vapor needed to achieve saturation increases as the temperature increases. As the temperature of a parcel of air decreases it will eventually reach the saturation point without adding or losing water mass. The amount of water vapor contained within a parcel of air can vary significantly. For example, a parcel of air near saturation may contain 8 g of water per cubic metre of air at , and 28 g of water per cubic metre of air at Three primary measurements of humidity are widely employed: abso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anhydrous
A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achieve perfect dryness; anhydrous compounds gradually absorb water from the atmosphere so they must be stored carefully. Solids Many salts and solids can be dried using heat, or under vacuum. Desiccators can also be used to store reagents in dry conditions. Common desiccants include phosphorus pentoxide and silica gel. Chemists may also require dry glassware for sensitive reactions. This can be achieved by drying glassware in an oven, by flame, or under vacuum. Dry solids can be produced by freeze-drying, which is also known as lyophilization. Liquids or solvents In many cases, the presence of water can prevent a reaction from happening, or cause undesirable products to form. To prevent this, anhydrous solvents must be used when perform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
