Kinetics of microwave degradation of λ-carrageenan from Chondrus ocellatus

λ-Carrageenan from Chondrus ocellatus was degraded by microwave. The changes in intrinsic viscosity [η] during degradation were investigated. Based on the concept that the random scission of glycosidic linkage basically obeys first-order kinetics, [η] for each short-term microwave process could be obtained. The degradation rate coefficient (kn) of kinetics equation describing the microwave degradation of λ-carrageenan on different conditions was determined. The results demonstrated that changes of external pressure play a most important role in degradation of λ-carrageenan for same short-term microwave process. The susceptibility to degradation is also related to molecular size and concentration of λ-carrageenan. But at higher stress, the relationship between kn and [η]n deviates first-order kinetics.