Out of which, up to 0.16% of the total cyanide
is contained in the tip, reducing to 0.01% in the base, with highest in leaves of young plants, but dropping rapidly after pollination.
Most methodologies of preparing samples for the determination of total cyanide
content consist of adding sodium hydroxide to pH greater than 12, which results in trapping the volatile forms of cyanides and then in carrying out the distillation operation.
[16.] Enidiok SE, Attah LE and CA Otuechere Evaluation of moisture, Total cyanide
and fiber contents of Garri produced from cassava varieties obtained from Awassa in Southern Ethiopia.
determination of plants and foods using the picrate and acid hydrolysis methods.
Physicochemical properties of the roots-Soluble solids: direct reading via an Atago optical refractometer at 20[degrees]C based on AOAC (1997) method 932.12; pH: direct reading via a Marconi pH meter based on AOAC (1997) method 943.02; total titratable acidity: titration method based on AOAC (1997) method 942.15; water activity (aw): direct reading via a Decagon Aqualab 3TE digital thermo hygrometer at 25[degrees]C; free and total cyanide
(HCN): enzymatic/spectrophotometric method based on ESSERS (1993); and color: tristimulus colorimetry using a model CR 400 MINOLTA colorimeter, with L*, a* and b* values based on the parameters D65 (day light) and 10[degrees](observer angle) according to CIE Lab standards (CHROMA METER, 1989).
OI Analytical's CNSolution 3100 Cyanide Analyzer performs ASTM D 7511-09e2, automating total cyanide
analysis and providing throughput of 30 samples/hr.
The total cyanide
content in mg kg-1 were calculated by the formula described by Bradbury et al.
An enzymatic assay for the total cyanide
content of cassava (Manihot esculenta Crantz).
EPA has prescribed standards for total cyanide
in drinking and aquatic-biota waters as 200 and 50 ppb; respectively [10, 11].
OI Analytical, College Station, Texas, has a compact modular system, the CNSolution Cyanide Analyzer, for flow injection analysis of available or total cyanide
. Available cyanide is measured in this instrument by a ligand-exchange gas diffusion technique coupled with amperometric detection in accordance with the appropriate EPA and ASTM methods.
CATC concentration is determined by chlorinating the available cyanide in the sample-using calcium hypochlorite (Ca[(OCl).sub.2]), measuring the HCN using the total distillation procedure (Method 335.2), and finding the difference between the total cyanide
measured before and after the chlorination.
Six ASTM methods covering sampling, preservation and analysis of free, available, and total cyanide
were included in the MUR.