a.Soft cheese--Soft cheese may mold faster in vacuum than in regular air. But hard cheese ok for vacuum sealing.
b.Raw fruits such as bananas, whole apples --They would decay faster in vacuum seal than regular air because of their natural ripening. If you want to vacuum seal apples you must slice it and put some lemon juice on the slices to prevent them from browning. For bananas, peal them before vacuum package, then put in the refrigerator or freezer.
c.Raw onions, garlic, raw mushrooms & Cruciferae vegetables such as radishes, watercress, kale, mustard greens, cabbage, lettuce etc.--They produce natural gases that may result in loss of vacuum and spoil the food.
d.Coffee beans--They release carbon dioxide that would result in loss of vacuum.
e.Freshly cooked or steamed veggies--Hot foods may cause loss of vacuum. So you must let foods come to room temperature before vacuuming and sealing.