What is the reason why the frozen food bag body of quick-frozen or frozen food is prone to breakage?

What is the reason why the bag body of quick-frozen or frozen food is prone to breakage?Quality issues:Some quick-frozen foods have a certain percentage of bag breakage (break at the non-sealing part) during storage, transportation and sales.Cause Analysis: ——Packaging Materialspoor cold resistance——When the packaging material is in a low temperature state, the flexibility decreases, the brittleness increases, and the impact resistance becomes poor. For example, in the anti-pendulum impact test, the impact energy of the same material before and after freezing is very different.poor flexibility——The packaging material has poor flexibility, low elongation deformation rate and high stiffness under normal environment, resulting in the packaging of the finished product under a certain internal gas pressure, the packaging material is not easy to produce a certain tensile deformation, and it is easy to form a resistance force, which leads to the rupture of the bag body. .Expert advice: ——Pay attention to the tensile strength of food packaging bags·Elongation and elastic modulus, pendulum impact energy, cold resistance, drop resistance, burst pressure(Positive pressure method)and other performance. ——Re-select packaging materials with better flexibility and cold resistance, or improve the quality of existing food packaging bag materials.