It took an out-of-this-world arrival to get that perfect chemical combination for water to fill our planet. Water may have come to earth by way of comets and asteroids. Morning dew and roaring falls inspire poets. Hurricanes and typhoons wreak devastation.
It's also necessary to store and handle the cut onions properly to further reduce the risk of bacterial contamination. Cutting Onions Ahead of Time Cutting onions the day before you need them is safe when you take the proper precautions.
From a microbiological standpoint, it would be safe forever. Palatability is another issue and will depend upon how good the freezer is and on the packaging used. Raw cuts of beef could be OK for 6-12 months. Ground beef or small pieces should be used within 3-4 months. Use up cooked beef within 3 months.