Potatoes starch granule size

The particle size distribution depends on the type of plant (see Table 5). The size of the potato starch granules is considerably higher than the size of com and tapioca starch granules. Also, the moisture absorption of potato starch is much higher than for com and tapioca starch. Thus, processing of tapioca starch in technical processes like compounding is similar to that of com starch [10]. 

Figure 10.3 Scanning electron micrographs (SEM) featuring (a) the presence of some small size nodules or protuberances on some potato starch granules and (b) surface fragmentation on some potato starch granules (source Singh et al., 2006).

Figure 5.19 (a) AFM image of a typical surface region of a potato starch granule (scan size 1000nm2,... 

Ji, Q Oomen, RJFJ Vincken, J Bolam, DN Gilbert, HJ Suurs, FCJM et al. Reduction of starch granule size by expression of an engineered tandem starch-binding domain in potato plants. Plant Biotechnology Journal, 2004, 2(3), 251-60. 

Modification, which involves the alteration of the physical and chemical characteristics of the native potato starch to improve its fimctional characteristics, can be used to tailor it to specific food applications. The rate and efficacy of any starch modification process depend on the botanical origin of the starch and on the size and structure of its granules. This also includes the surface structure of the granules, which encompasses the outer and iimer surface depending on the pores and channels, which cause the development of the so-called specific surface (Juszczak, 2003). Potato starch modification can be achieved in three different ways physical, conversion, and chemical (derivatization) (Table 10.6). 

Chen, Z., Schols, H. A., Voragen, A. J. G. (2004). Differently sized granules from acetylated potato and sweet potato starches differ in the acetyl substitution pattern of their amylose populations. Carbohydr. Polym., 56, 219-226. 

Singh, N., Kaur, L. (2004). Morphological, thermal and rheological properties of potato starch fractions varying in granule size. J. Sci. FoodAgric., 84,1241-1252. 

Yoneya, T., Ishibashi, K., Hironaka, K., Yamamoto, K. (2003). Influence of cross-linked potato starch treated with POC13 on DSC, rheological properties and granule size. Carbohydr. Polym., 53,447-457. 

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