Bacteriological techniques for dairy purposes.

  • Great Britain. Ministry of Agriculture, Fisheries and Food.
Date:
1968
Catalogue details

Licence: Public Domain Mark

Credit: Bacteriological techniques for dairy purposes. Source: Wellcome Collection.

    189/192 (page 181)
    Interfering Substances Copper as Cu2+ Iron as Fe 3+ Aluminium as Al Manganese as Mn?#+ Phosphate as jh Be Sodium hexa- metaphosphate OZ, Greater than 200 Effect In the presence of more than 0-2 p/m Cu** no end point can be obtained. A slightly red end point is obtained in the presence of up to 0-2 p/m Cu*+ As the iron content increases up to 20 p/m the end point becomes progressively greyer. As the aluminium content increases up to 50 p/m the end point becomes progressively redder. Causes no interference with end point but titrates as hardness. 1 p/m Mn?+=1-8 p/m CaCo,. 200 p/m causes no interference. As the concen- tration of PO, increases above 200 p/m the initial colour becomes more mauve but with care the end point can still be detected. Each 10 p/m will sequester about 1 p/m of hard- ness expressed as CaCO . Ps205922