Please note that vacuum-packing increases the shelf-life of most if not all foods, these will taste better longer.

Only systems with electric pumps will come close to evacuating enough air and oxygen to be effective.

What vacuum-packing will not do is preserve food subject to microbiological invasion, like meat, dairy and fresh vegetables, against going bad. You must still take the same precautions like refrigeration.

Ambient moisture, sugar and acid content already in foods will continue to change them chemically and texturally making them unpalatable. This cannot be solved by vacuum-packing.

Any vacuum-packing system is only as good as the plastic bag or material. If this is compromised in manufacturing or as occasioned in storage and handling, the material may fail to be airtight.

There are some unexpected benefits to vacuum-packing you'll find in small situations such as repackaging brown sugar. Ordinarily, brown sugar will not keep because it dries out, becomes hard and cannot easily be used after that happens. Vacuum-packing solves that.

Here are some general benefits.

Shelf life of vacuum-packaged foods comparison with normal shelf life.

Food Stored in Normal Shelf-life Vacuum Shelf-life
Large cuts of meat
beef, poultry, lamb and pork
Freezer 6 months 2-3 years
Ground meat
beef, poultry, lamb and pork
Freezer 4 months 1 year
Fish Freezer 6 months 2 years
Coffee beans Room temperature 4 weeks 16 months
Coffee beans Freezer 6-9 months 2-3 years
strawberries, raspberries, blackberries
Refrigerator 1-3 days 1 week
cranberries, huckleberries, blueberries
Refrigerator 3-6 days 2 weeks
Cheese Refrigerator 1-2 weeks 4-8 months
Cookies, crackers Room temperature (periodically opening) 1-2 weeks 3-6 weeks
Flour, sugar, rice Room temperature 6 months 1-2 years
Lettuce Refrigerator 3-6 days 2 weeks
Nuts Room temperature 6 months 2 years
(with no preservatives)
safflower, canola, corn oil
Room temperature 5-6 months 1-1½ years
Wine Refrigerator 1-3 weeks 2-4 months