Vacuum packing food is a great way to extend its shelf life because microorganisms are robbed of an environment in which to live. Removing oxygen from its surroundings makes the food last three to five times longer. This blog provides a step-by-step guide that explains how easy it is, whether you are using a vacuum sealing machine or a manual pump.
Pre-pack prep
These steps should be completed regardless of whether a machine or manual pump is used.
Wash your hands
Thoroughly wash your hands with soap. Avoid unnecessarily touching food with bare hands, even after washing them. Consider wearing gloves.
Clean the food
Vegetables and fruit should be cleaned of all dirt. Scrub or wash, even peel away the skin if necessary, to remove unwanted material. If items are washed, thoroughly air dry them, using absorbent paper or a clean cotton towel to assist.
Meat should be trimmed of unwanted fat, skin and bone. The main objective is to remove unwanted material that represents unnecessary bulk.
Fish should be scaled, gutted, thoroughly rinsed (ideally with seawater) and then patted down with absorbent paper or a clean cotton towel to remove excess moisture.
Separate food items into individual portion sizes
Vacuum bagging works best when there is no excess bulk in the bag. Do not needlessly cram a bag full to its limit. Divide the food into individual meals or serving-sized portions.
Pre-freeze meat & fish
Meat and fish should be pre-frozen before vacuum sealing. Pack the items in a freezer bag and freeze for a day or two before vacuum sealing.
Some people like to vacuum pack meat that would otherwise be air aged. These meats are not pre-frozen.
Vacuum pack only the freshest food
It goes without saying that the fresher is the food that you vacuum seal, the longer it will last.
When buying frozen food to put in the vacuum bag, select items at the store with the most distant use-by date.
Using a vacuum bagging machine
Vacuum bagging machines can be expensive, some costing several hundred dollars. Nevertheless, many people prefer them to manual pumps since they find machines to be quicker and easier to use, and claim they are more effective in removing air from the storage bag.
Place the food inside the plastic bag
Most machines require using a specific brand of bag, typically the same brand as the machine. The vacuuming or sealing process may be less effective if this instruction is not followed.
Place the open edge of the bag into the machine
Depending on the model of the machine, it will either have a sensor that detects the bag and start automatically, or you may need to press a button to initiate the vacuum process.
Watch the machine suck air out of the bag
This is typically a straightforward operation. No action by you is required, other than holding the bag still. The bag will progressively shrink.
Wait for machine to signal the operation is complete
Remove the bag and store it in the pantry, refrigerator or freezer.
Using a manual pump
One advantage of manual pumps is that they do not require electricity. This can be an advantage for campers and boaters wanting to vacuum bag food in remote locations.
Place the food inside the plastic bag or container
Many manual systems use plastic containers rather than bags. One of their disadvantages is that they are usually cylindrical in shape and consume more storage space.
Place the food inside the bag or container
Seal the bag or tighten the lid on the container.
Put the nozzle end of the pump into the hole on the bag or container
Press on the pump repeatedly until all oxygen is sucked from the bag or container
It will be obvious when all the air has been removed since you will not feel any air coming out of the pump when pressed.
Remove the nozzle from its hole
The nozzle hole is designed to prevent air from entering the bag or container once the pump has been removed.
Place the container or bag in the pantry, refrigerator or freezer.
Post-Pack Issues
Bacteria can survive in an air-depleted environment. Vacuum packed food may become contaminated, particularly unfrozen meat. Food odour and colour are the tell-tale signs of adulteration.
It is normal for unfrozen, vacuum-sealed meat to have a strong odour after being opened. However, this should dissipate after 30 minutes of airing. If the odour persists, do not use the meat.
Similarly, it is not unusual for unfrozen, vacuum-sealed meat to darken in colour. However, if it turns black with streaks of purple, throw it away.
For more information about food health and safety, why not take an Accredited Food Handling and Food Safety Supervisor course?