| 摘要 |
food-processing industry; detection of adulteration of juice and dairy products; analysis of sewage and other contaminants. SUBSTANCE: method consists in drawing sample, clarifying it by settling or filtering and dividing it into two portions. Oxidant is added to first portion and sulfuric acid is added to second portion; then, both portions are subjected to photometric measurement; their optical density E11 and E21, is measured and indicator is added, after which photometric measurement is repeated and optical densities E12 and E22 are measured again; content of tartaric acid (Ct.a.) and/or its salts is calculated by the following formula: (Ct.a.) = K(E22-E21)-(E12-E11), where K is proportionally factor. Oxidation of first portion of first portion of sample may be effected by means of hydrogen peroxide or another agent whose standard electrode potential of reduction in acid medium ranges from 1 to 1.8. Ammonium vanadate is used indicator. EFFECT: enhanced accuracy; reduced time of analysis; reduced limit of detection; extended field of application. 8 cl |
