To solve the problem at hand, use your five senses. (Theyre not doing anything anyway.) Weve already covered the visual aspects of the refrigerator door and surrounding environs. The power of smell cannot be excluded from this impromptu, albeit insignificant, study. We all know that the subject never was roses, but smell along with sight will never fail to direct you to the problem areas in your refrigerator. Try to do it gently or your nostrils will never be the same. Talk to the smell and assure it that it will be in its proper home very soon. Then be strong and throw the item out. Whatever it was, its garbage now.
The power of touch can be under-rated. Feeling suspicious items can be a bit more adventurous and is not recommended for the faint hearted. There is no guarantee that whatever is inside wont feel you back and you might not like that. Proceed at your own risk. If you must touch, stroke gently, but throw out anything suspicious immediately if you feel any sort of pulse. Better yet, flush it down the toilet where it cant come back and hurt you. Sometimes, its every feel for itself in this selfish world of ours.
Try to find a way to identify the older items in your refrigerator. One cannot ask their age as that is improper, but one can employ other techniques that can help us do so. Different colored foil; use it even if it hasnt been invented yet. Use green for items wrapped in April, red for December, orange for October etc. etc. This way, one can spot at a glance the old from the new (but not the borrowed from the blue). Labels might be of some help, but thats only if they can be seen. The writing wears off as the food gets older and gunkier, waiting for you to notice it. Once you get everything neat and clean and organized, you will be so proud of yourself. This only happened to me once. It lasted but a minute or two, until I realized I was in someone elses house!