Benders'dictionary of nutrition and food technology

122(2) A technique used to encapsulate flavouring materials.See encapsulation.coagulase The name given to an enzyme said to be present inmilk and to account for the ability of milk to clot a solution offibrinogen.coagulation (1) A process involving the denaturation of proteins,loss of their native, soluble, structure, so that they become insoluble;it may be effected by heat, strong acids and alkalis, metalsand various other chemical agents. Some proteins are coagulatedby specific enzymic action. Denaturation is due to the breakingof hydrogen bonds that maintain the protein in its native structure.As the process continues, there is considerable unfolding ofthe protein, and interaction between adjacent molecules, formingaggregates which reach such a size that they precipitate.(2) The final stage in blood clotting is the precipitation offibrils of insoluble fibrin, formed from the soluble plasma proteinfibrinogen, an example of coagulation caused by enzymic action.The enzyme responsible is prothrombin (EC 3.4.21.5), which isnormally inactive, and is activated by a cascade of events inresponse to injury. vitamin k is required for the synthesis of prothrombin,and clotting requires calcium ions.coalfish See saithe.cob nut See hazel nut.cobalamin See vitamin b 12 .cobalt A mineral whose main function is in vitamin b 12 , althoughthere are a few cobalt-dependent enzymes. There is no evidenceof cobalt deficiency in human beings, and no evidence on whichto base estimates of requirements for inorganic cobalt. ‘Piningdisease’ in cattle and sheep is due to cobalt deficiency (theirrumen micro-organisms synthesise vitamin B 12 ). Cobalt saltsare toxic in excess, causing degeneration of the heart muscle,and habitual intakes in excess of 300 mg/day are consideredundesirable.cobamide Obsolete term for coenzymes derived from vitamin b 12 :adenosyl and methyl cobalamin.Coca Cola TM A cola drink.See also coca leaves.coca leaves From the S American plant Erythroxylon coca; theycontain the narcotic alkaloid cocaine, and are traditionallychewed by the natives of Peru as a stimulant. Originally the beverageCoca Cola (see cola drinks) contained coca leaf extract,although this was removed from the formulation many years ago.cocarboxylase An obsolete name for thiamin diphosphate, themetabolically active coenzyme derived from vitamin b 1 .