Studies on Conformation Transitions of Konjac Glucomannan in Food Processing with The Circular Dichroism

摘要

The Influence of different temperature, pH value, metallic ion and non-metallic ion on conformational transitions in solution of konjac glucomannan (KGM) was investigated by using circular dichroism (CD). The results showed that it brought a new cotton effect when in high pH value, which predicates that the conformation changed sharply from disordered to ordered structure. However the rest affecting factors, such as temperature et al, mainly induced the changes of CD value ([?]) in different extent rather than giving new Cotton effect or the absorption peak drift. So it can be concluded that the native conformation of KGM had no quite ordered structure, and acetyl group had great influence on the conformation. By means of the structure changes mentioned above, The correlation between conformational transitions and functionality of KGM when treated by different temperature, pH value, metallic ion and non-metallic ion in food process, such as swelling behavior or anti-swelling character of konjac flour, formation of thermally stable konnjaku gel, release of Ca{sup}(2+) in gel food and so on, were discussed also.