[Determination of tin in food products using pyrocatechol violet]

Some incorrect points are referred to of Part II of Bulgarian State Standard 6853-74 "Canned fruits, vegetables, meat, and meat-and-vegetables. Determining the content of stannum with the use of pyrocatecholviolet" rendering difficult the analytic process and leading to false results. Another method for the evaluation of the stannum content making use of pyrocatecholviolet has been applied instead as suggested by the International Federation of Chemists. It makes feasible the determination of even small amounts of stannum (0-30 mug) which are usually encountered in the food products. A mathematic and statistical processing of the results obtained has been made.