The objective Of this study was to determine if microbial transglutaminase (mTG) is capable of maintaining quality traits of fresh beef cuts stored at -35 degrees C for 5 weeks, and to find out if mTG catalyses proteins at freezing temperatures, which could be used in industrial situations. For comparison, other materials were also used, including polyethylene sheets and extract of muscle proteins. This study provides evidence that mTG works at low and even freezing temperatures. Surprisingly, mTG denaturised the extracted proteins at -35 degrees C, and had the potential to decrease hardness, reduce weight loss, and protect against colour deterioration of beef muscles during 35 days of storage. This study extends the hypothesis that frozen meat steaks can be preserved by a smart film (edible protein-based film) generated from mTG with muscle proteins. The polymerisation activity of mTG could benefit the food industry or even have medical applications in the near future.