Report to the Local Government Board by Dr. J. M. Hamill on the presence of calcium sulphate in baking powder and self-raising flour.

  • Hamill, J. M.
Date:
1911
Catalogue details

Licence: Public Domain Mark

Credit: Report to the Local Government Board by Dr. J. M. Hamill on the presence of calcium sulphate in baking powder and self-raising flour. Source: Wellcome Collection.

    18/20 page 16
    The presence of much calcium sulphate in the residue left by the powder after it has done its work in the loaf seems to be unavoidable. The statement that it is converted into the easily soluble sodium sulphate is not borne out by experiment. <A portion of a loaf baked with a powder containing pure acid calcium phosphate, calcium sulphate, and sodium bicarbonate far in excess of the neutralising power of the phosphate, was dried, very finely powdered, and shaken up with chloroform. A heavy sediment of mineral matter was obtained which contained no calcium carbonate, and in which only one quarter of the total combined sulphuric acid was present as sodium sulphate. To whatever extent the formation of sodium sulphate may occur during baking, the ultimate fate of the combined sulphuric acid is to be reconverted once more into calcium sulphate when it reaches the stomach. A mixture of tri-calcium phosphate, sodium sulphate and excess of dilute hydrochloric acid of the strength of the gastric juice, after standing for a short time was found to contain a residue insoluble in strong acid and consisting, as would be expected, entirely of calcium sulphate. Ceci, H, Crisp.
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