Abstract:The effect of freezing-thawing cycles（0-4）on the quality of frozen semifinished Xinjiang naan during storage and transportation was studied.The changes of moisture migration state，rheological properties，microstructure，and protein secondary structure of frozen semifinished Xinjiang naan in freezing-thawing cycles were measured by a low-field nuclear magnetic resonance instrument，a rheometer，a scanning electron microscope，and a Fourier infrared spectrometer，respectively.The sensory quality of Xinjiang naan was evaluated through baking experiments，on the basis of which the backing characteristics were analyzed.The results showed that with the increase in freezing-thawing cycles，the tensile strength，tensile distance，and rheologicalproperties（elastic modulus G'and viscous modulus G''） of frozen semifinished Xinjiang naan decreased significantly.The strongly bound water continuously decreased；the weakly bound water presented a decreasing-increasing-decreasing trend；and the free water increased slightly.As the freezing-thawing cycles increased，obvious voids and dents appeared in the frozen semifinished Xinjiang naan，and the protein secondary structure became loose and disordered with decreased β -sheets and increased β -turns.Moreover，repeated freezing-thawing led to a decrease in the specific volume，an increase in hardness，and a decrease in comprehensive sensory score.The results suggested that the freezing-thawing should not exceed 4 cycles for the frozen semifinished Xinjiang naan in storage and transportation.