Starch granules storage tissues

Intrinsic factors that may influence potato digestibility include the structure of the starch molecules, the structure of starch granules, the composition of the potato, the presence of phosphate in starch granules, tissue structure, and factors that may affect these, including agronomic and growth history, storage, maturity, and variety. 

During very active periods of photosynthesis, triose phosphates are converted to starch. Under normal conditions, approximately 30% of the CO, fixed by leaves is incorporated into starch, which is stored as water-insoluble granules. During a subsequent dark period, most chloroplast starch is degraded and converted to sucrose. Sucrose is then exported to storage organs and rapidly growing tissues. In these tissues (e.g, tubers and seeds), most sucrose molecules are used to synthesize starch, which is stored primarily within a specialized plastid called an amyloplast. 

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