This study investigated and compared meat color, thawing loss, cooking loss, and shear force of beef subjected to normal freezing and quick freezing. The microstructure of frozen beef was also studied by HE staining, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that theH value of bovine tendon muscle subjected to quick freezing-thawing process rose by only 0.9%, compared to as high as 9.4% for the normally frozen and thawed sample, suggesting a significant difference between both freezing methods (P< 0.05). Thawing loss of beef tendon muscle subjected to normal freezing was significantly higher than that of the sample subjected to fast freezing (P< 0.01). At the same time, cooking loss of beef tendon muscle subjected to normal freezing was also significantly higher than that of the samples subjected to fast freezing (P< 0.05). In addition, shear force of beef tendon muscle subjected to normal freezing was lower but not significantly than that of the quick-frozen and control groups. Electron microscopy results showed that normal freezing could result in noticeably bigger intermuscular gap and larger intermyofibrillar space in thawed beef when compared with fast freezing, and it also destroyed the cross-sectional area of muscle fibers. On the other hand, fast freezing could protect the bright color of beef and improve its eating quality. In addition, fast freezing could greatly reduce the size of ice crystals in meat, protect the microstructure of meat, and optimize the taste of meat.%通过对比普通冷冻工艺与快速冷冻工艺对牛腱子肌的色泽、解冻汁液损失率、蒸煮损失率、剪切力指标的影响，并且结合苏木精-伊红染色法、扫描电子显微镜、透射电子显微镜观察两种冷冻工艺对牛肉组织结构的影响。结果发现：快速冷冻工艺使解冻后牛腱子肌的H值仅上升了0.9%，而普通冷冻工艺处理后的H值上升了9.4%，两种冷冻工艺对H值的影响差异显著（P＜0.05）。普通冷冻工艺处理的牛腱子肌解冻汁液损失率极显著高于快速冷冻工艺（P＜0.01）。同时，普通冷冻工艺处理的牛腱子肌的蒸煮损失率明显高于快速冷冻工艺，两者差异显著（P＜0.05）。另外，普通冷冻工艺处理的牛腱子肌的剪切力低于快速冷冻工艺和对照组，但是差异不显著。电子显微镜观察得出，普通冷冻工艺处理明显比快速冷冻工艺处理处理使解冻后牛肉的肌束间隙更大、肌原纤维间隙更大，同时普通冷冻工艺也破环了肌纤维横截面的结构。结果表明：快速冷冻工艺很好地保护了牛肉鲜艳的色泽，提高肉的食用品质。另外，快速冷冻工艺极大地降低了肉中冰晶的大小，保护了肉的组织结构，优化了肉的口感。
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