Starch

For sem 3 B.pharm students GTU

1. Starch Prepare by : Milan Chovatiya B.Pharm Sem - 3 Guide by: Mrs. Pooja Khanpara APIP, Jamnagar

2. Starch Content Synonym Biological source Geographical source Preparation of Starch Description of starch Chemical constituents Identification Uses Adulterants

3. Synonyms : Amylum Biological source : Consists of polysaccharides granules obtained from grains of maize (Zea mays L.) Rice (Oryza savita) or wheat (Triticum aestivum L.) Family : Gramineae or from tubers of potato (Solanum tuberosum L.), family solanaceae .

4. Geographical source: Most of tropical as well as , subtropical countries prepare starch commercially. India.

5. Preparation of Starch: Depending upon the raw material to be used for processing or type of starch to be produced. Different processes : are used for commercial manufacture of starch Washing and softening are involved Grinding and sieving Tabling or centrifugation De-watering and drying of starch The recovery of by-products

6. Conti… Potato starch : Potatoes are washed, crushed or cut and converted to a slurry filtered . Milky slurry containing starch is purified by centrifugation , washed , dried and sent to the market. Rice starch : Broken pieces of rice soaked in water with the sodium hydroxide 0.5% solution. Crushed, centrifugation , dried. Pulverised and packed.

7. Maize and corn starch : Grains are washed , softened , sulphur dioxide is passes to prevent fermentation, milling. The germs (embryo) are separated. Antibiotics like penicillin, germs oil ( corn oil) are produced as by-products. Sieving, washing are done. The starch being heavier, dried in dryer and starch is prepared.

8. Wheat starch : Wheat flour is dough ,kept for a time, threshed or grind on grooved rollers, with watering shaking to take out starch, dried and packed.

9. Description of starch Starch occurs as fine powder or irregular, angular masses. Colour : Rice starch - white , wheat - cream and potato - slightly yellowish. Odour : Odourless Taste Mucilaginous Size and shape : Different types as under:

10. Microscopic characters : Rice starch : The granules are ( i ) simple – polyhedral, 2-12 micron in diameter.(ii) compound granules are ovoid, 12 to 30 μ × 7 to 12 μ in size, with 2 to 150 component. Wheat starch : Simple, lenticular , circular or oval in shape, 5 to 50 μ in diameter. The granules contain hilum at the centre and the concentric faintly marked straiations . Rarely compound granules with 2-4 components.

11. Maize starch : Polyhedral or rounded, 5 to 31 μ in diameter, with distinct cavity in center, and 2 to5 rays cleft. Potato starch : Simple granules. Sub-spherical, flattend . Irregularly avoid in shape. 30 to 100 μ in size. Hilum is present near narrower red with well marked concentric striations. Starch is insoluble in water and alcohol.

12. Chemical constituents : That contain two polysaccharides viz. ( i ) amylose ( β – amylose ) and amylopectin ( α – amylose ) in the proportion of 1:2. Amylose is water soluble while amylopectin is water insoluble. Swell in water Responsible for the gelatinising property of starch.

13. Identification test 1.     Boil 1 g of starch with 15 ml of water and cool. The translucent viscous jelly is produced. 2.     The above jelly turns deep blue by the addition of solution of iodine. The blue colour disappears on warming and reappears on cooling.

14. Uses Used as a nutritive, demulcent, protective and as an absorbent. Used in the preparation of dusting talcum powder for application over the skin. As antidote in iodine poisoning, as a disintegrating agent in pills and tablets, and as diluent in dry extracts of crude drug. It is a diagnostic aid in the identification of crude drugs.

15. Conti… Glycerin of starch is used as an emollient and as a base for suppositories. Also a starting material for the commercial manufacture of liquid glucose, dextrose and dextrin. Starch is industrially used for the sizing of paper and cloth.

16. Substitutes and Adulterants Tapioca starch or Cassava or Brazilian arrowroot- This starch is obtained from  Manihot esculenta  (Euphorbiaceae) and is used as substitute for starch.