PHYSICAL MODIFICATION OF STARCH-REALLY PHYSICAL?

Among three different ways of starch modification: physical, chemical and enzymatic, the first one is recognized as causing changes only in supermolecular structure of this polysaccharide. However, modern analytical techniques proved the above theory wrong. The review of the current state of knowledge regarding changes in molecular and supermolecular structure of starch due to physical modification is provided in this study. Summarising the current state of knowledge - physical modification causes several changes in both molecular and supermolecular structure of starch. Water is of crucial importance for the course and effects of these processes. Its amount determines the possibility of crystallization or recrystallisation by microwave or hydrostatic pressure treatments. Water is not only a medium in which the modification processes take place but also is a chemical reagent. The most common chemical reactions are hydrolysis/degradation of starch macromolecules and transglycosidation. Cross-linking and oxidation are rarely observed.