Maize Starch

(Ph. Eur. monograph 0344)

Excipient.

When Starch is specified and the type is not indicated, Maize Starch, Potato Starch, Rice Starch, Wheat Starch or, in tropical countries where these are not available, Tapioca Starch may be supplied or used.

Ph Eur

Maize starch is obtained from the caryopsis of Zea mays L.

Matt, white to slightly yellowish, very fine powder that creaks when pressed between the fingers.

Practically insoluble in cold water and in ethanol (96 per cent).

The presence of granules with cracks or irregularities on the edge is exceptional.

A. Examined under a microscope, using not less than 20 × magnification and using equal volumes of glycerol R and water R, it appears as either angular polyhedral granules of irregular sizes with diameters ranging from about 2 µm to about 23 µm or as rounded or spheroidal granules of irregular sizes with diameters ranging from about 25 µm to about 35 µm. The central hilum consists of a distinct cavity or 2- to 5-rayed cleft and there are no concentric striations. Between orthogonally orientated polarising plates or prisms, the starch granules show a distinct black cross intersecting at the hilum.

B. Suspend 1 g in 50 mL of water R, boil for 1 min and cool. A thin, cloudy mucilage is formed.

C. To 1 mL of the mucilage obtained in identification test B add 0.05 mL of iodine solution R1. An orange-red to dark blue colour is produced, which disappears on heating.

4.0 to 7.0.

Shake 5.0 g with 25.0 mL of carbon dioxide-free water R for 60 s. Allow to stand for 15 min.

Examined under a microscope using a mixture of equal volumes of glycerol R and water R, not more than traces of matter other than starch granules are present. No starch grains of any other origin are present.

Maximum 20 ppm, calculated as H₂O₂.

Maximum 50 ppm.

Maximum 10 ppm.

Shake 1.5 g with 15 mL of dilute hydrochloric acid R. Filter. The filtrate complies with the test.

Maximum 15.0 per cent, determined on 1.000 g by drying in an oven at 130 °C for 90 min.

Maximum 0.6 per cent, determined on 1.0 g.

TAMC: acceptance criterion 10³ CFU/g (2.6.12).

TYMC: acceptance criterion 10² CFU/g (2.6.12).

Absence of Escherichia coli (2.6.13).

Absence of Salmonella (2.6.13).

Ph Eur