Starch grains sizes

Micronutrients do also affect potato quality and yield applications of B, Mn, and Zn increase the starch grain size, while applications of iodine or ammonium molybdate increase the dry matter and starch content. 

Starches remain a popular glidant, in particular those with the larger grain sizes such as potato starch, possibly because of their additional value as a disin-tegrant in the formulation. Concentrations up to 10% are common, but it should be appreciated that excess may result in exactly the opposite effect of that desired (i.e., flow properties may worsen). Talc is also widely used and has the advantage that it is superior to starches in minimizing any tendency for material to stick... 

At 35 DAP, the endosperm had reached its maximum size and had started drying—the cells eventually dying, with starch grains filling them completely. The pericarp was crushed by expanding endosperm, becoming the final outer fruit coat composed of thick-walled dead cells. 

Lathe and Ruthven (1956), in a discussion of the penetrability of solutes in starch grains, suggested that solute molecules may penetrate only to the depth at which their diameter is equal to the distance between the amylopectin chains. This should explain why the stationary volume available for a solute is determined by its molecular size. They expressed the viewpoint that the graded penetration of solute according to this mechanism might be unique to starch. In view of present knowledge it appears that most, if not all xerogels may act as molecular sieves. 

The amount of moisture contained in starch becomes larger as the grain size of the starch increases potato starch contains about 15% and wheat starch about lk% of moistvire. When the humidity increaes to a higher value, the moisture content increases further 20 30% in potato and l8 27% in wheat starch at 80- 90% relative humidity(Handbook for manufacturing of confectionery, p.27(1968)l,... 

Fortuna T, Juszczak L. Palasinski, phosphorylation of potato starch classified in terms of grain size. Zywnosc 2000 4 (25) 91-98. (in polish). 

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