Abstract:To explore the effects of fast immersion freezing，tunnel freezing，and freezer freezing on the quality and microstructure properties of the beef，the indexes of freezing rate，beef color，loss rate of thawed juice，and microstructure of beef tissue were determined. Results showed that compared with tunnel freezing and freezer freezing，fast immersion freezing significantly accelerated the freezing rate（P＜0.05），which was 2.0 times that of tunnel freezing and 10.6 times that of freezer freezing，and it had the shortest time to pass through the zone of maximum ice crystal generation. The loss rate of thawed juice，total volatile basic nitrogen（TVB-N）value，thiobarbituric acid reactive substances（TBARS）value，and total carbonyl content were decreased in the beef after fast immersion freezing，while the L* value（except for the 7th day），a*value，hardness，and total sulfhydryl content were higher than those of tunnel freezing and freezer freezing. The beef after fast immersion freezing possessed better microstructure，and the ice crystals formed in the cells were small and evenly distributed，with small damage to muscle tissue. Therefore，fast immersion freezing could better maintain the quality of beef than the other two freezing methods.