Determination of Ascorbic Acid in Presence of Interfering Substances by the ‘ Continuous-Flow’ Method

The Ascorbic Acid Content of Potato Tubers

“…The continuous flow method, described by Harris & Mapson (1947), was therefore used. This method will differentiate qualitatively ascorbic acid from most other known indophenol reducing substances.…”

“…In view of their results, which suggest that even under the best conditions the biological test cannot determine the vitamin C activity with an error of less than 5%, and that, with material low in ascorbic acid, an error of 20% may be encountered, we felt that no useful purpose would be served, at this stage, in checking our results biologically. The continuous flow method, described by Harris & Mapson (1947), was therefore used. This method will differentiate qualitatively ascorbic acid from most other known indophenol reducing substances.…”

Happy Birthday BJN!

“…The ‘gem’ of the very first issue of the BJN is Magnus Pike's paper describing the nutrient content of English prison diets in 1944 6 . Other articles in the first issue describe a method for measurement of ascorbic acid 7 , and studies on reproduction and lactation in rats 8 , vitamin E deficiency 9 , and composition of sows' milk 10 . Two of the five articles in the first issue were from the University of Reading 8 , 10 and two were from the Dunn Nutritional Laboratory, Cambridge 7 , 9 .…”

“…Other articles in the first issue describe a method for measurement of ascorbic acid 7 , and studies on reproduction and lactation in rats 8 , vitamin E deficiency 9 , and composition of sows' milk 10 . Two of the five articles in the first issue were from the University of Reading 8 , 10 and two were from the Dunn Nutritional Laboratory, Cambridge 7 , 9 . The ‘proceedings’ articles in that issue deal with a meeting dedicated to Education in Nutrition held in Glasgow; these include an article on ‘The teaching of nutrition to medical students’ 11 , a topic which remains relevant today 12 .…”

The Ascorbic Acid Content of Potato Tubers

“…Reference has been made above to the high content of total ascorbic acid of 6 6 mg./g./ioo g. fresh weight, which was attained after some 40 days in air at -0-6 C. Special tests using the 'continuous-flow' method (Harris & Mapson, 1947) gave no evidence that this high reducing value was due to substances other than ascorbic acid (Barker & Mapson, 1950).…”