standard testing procedure starch IP

Storage Requirements:
Store protected from light and moisture.

Sampling:
Sample from each container / bag, if the consignment is of 03 or less than three containers / bags. If the number of containers / bags is more than 03and are up to 100, sample at randomly using the formula root (n) +1 where n is the number of containers/bags in the consignment. For the consignment of more than 100 containers/bags, sample additional containers/bags for every 100 containers/bags and thereafter. Collect a minimum of 5g from each of the randomly selected containers/bags in to individually no toxic, self sealing transparent polyethylene bearing ‘Sample For Analysis label kept in another transparent self sealing polythene bag. Afetr completion of sampling return rest sample on the same container. Collect control sample in Pet bottle/Glass bottle.

Quantity of Composite Sample:

40 g

Quantity of Control Sample:

2 X 40 g

Description: A very fine, white or slightly yellowish powder or irregular white mass which are readily reducible powder, creaks when pressed between the fingers; odourless and tasteless. The presence of granules showing cracks or edge irregularities is exceptional in starches other than wheat starch; wheat starch may contain granules with cracks on the edges.

Solubility: Practically insoluble in cold water, in acetone, in ethanol (95 per cent).

Identification:

A. Corn or maize starch: A distinct black cross is seen intersecting at the helium.
B. Which gives thick and more transparent mucilage.
C. Which disappears on heating and reappears on cooling

Acidity: Not more than 2.0 ml is required to change the colour of the solution.

Iron: 40ppm

Fluorescence: No Fluorescence is visible

Oxidising Substances: Blue colour is observed.

Microbial Contamination: 1g is free from E.coli and 10.0gm salmonellae and Shigella.

Sulphated ash: NMT 0.6%w/w.

Loss on Drying: NMT 15.0% w/w.

Description: A very fine, white or slightly yellowish powder or irregular white mass which are readily reducible powder, creaks when pressed

between the fingers; odourless and tasteless. The presence of granules showing cracks or edge irregularities is exceptional in starches

other than wheat starch; wheat starch may contain granules with cracks on the edges.

Solubility: Practically insoluble in cold water, in acetone, in ethanol (95 per cent).

Identification:

A. Corn or maize starch: Polyhedral granules 2 to 23µm in size , or rounded granules, 25 to 32µm in a
diameter. The central hilum consists of a distinct cavity or two to five –rayed cleft: no concentric striations. Viewed between

crossed nicol prisms a distinct black cross is seen intersecting at the helium.
B. Heat to boiling for 1 minute a suspension of 1g in 50ml of water and cool; a thin and cloudy
mucilage is produced with all starches except potato starch which gives a thick and more transparent
mucilage.
C. To 10ml of the mucilage obtained in test B add 0.05 ml of 0.01 M iodine; a dark blue colour is
produced which disappears on heating and reappears on cooling

Acidity: Add 10.0 g to 100ml of ethanol (70 per cent) previously neutrilised to phenolphthalein solution, shake
for 1hour, filter and titrate 50ml of the filtrate with 0.1M sodium hydroxide. Not more than 2.0 ml is required to change the colour of the solution.

Iron: Dissolve the residue obtained in the test for sulphated ash in 4ml of hydrochloric acid with the aid of
gentle heat, dilute with water to 50ml and mix; 25ml of the resulting solution complies with the limit test
for iron (40ppm).

Fluorescence: No Fluorescence should be visible under screened ultra-violet.

Oxidizing Substances: To 5.0 g add 10ml of water and 1ml of acetic acid and stir until a homogeneous
suspension is obtained. Add 0.5ml of a freshly prepared saturated solution of potassium iodide, mix and allow to stand for 5 minutes; no

distinct brown or blue colour is observed.

Microbial Contamination: 1g is free from E.coli and 10.0gm salmonellae and Shigella.

Sulphated Ash: Weight accurately 2.0gm of sample in silica crucible ignite in muffle farness at 700ºC for 120 minutes.