Vacuum sealing helps prolong the storage life of your produce by keeping out oxygen that causes food to spoil more quickly. Proper use ensures that your vegetables retain the best quality while remaining safe to eat, if you combine sealing with safe food storage procedures.
Selection and Preparation
Vacuum sealing alone won’t guarantee the freshness or safety of your vegetables. Begin with vegetables at their peak quality and avoid storing overripe, wilting or damaged vegetables. Before preparing or storing, wash vegetables thoroughly. Scrub root vegetables, like carrots, with a vegetable brush to remove any dirt. Wash more tender vegetables, including leafy greens, peppers and beans, in cool water. Before sealing, trim out any bad spots, remove stems and slice the vegetables into the desired storage size.
Blanching stops the natural enzyme process inside vegetables that can lead to color, texture or flavor changes. To blanch, cook the vegetables briefly in boiling water and then cool them immediately in ice water. Boiling times depend on the size and type of vegetable. Dense vegetables like squash require cutting into 1/4-inch slices to blanch properly, while carrots and cabbage will blanch when cut into 1/2-inch slices or strips. Vegetables like beans are left whole. Tender, quick-cooking vegetables, like peppers, can be cut into halves or strips, as desired. Blanch tender, quick-cooking vegetables like beans and peppers for 2 to 3 minutes, or just until their color brightens but before they begin to soften. Denser, slower-cooking vegetables, including broccoli, carrots and cauliflower, require 3 to 5 minutes. Keep the vegetables in the ice water until they are cold, and then drain and dry them before vacuum sealing.
Only use clean, new bags made specifically for your vacuum sealer model to ensure that everything seals properly. Two bag styles are commonly available: pre-sized bags with only the bottom sealed, or long rows of bags that you cut to size and seal both the bottom and top. When cutting your own bags, make them large enough to hold all the vegetables with several inches of headspace at the top. The amount of headspace depends on the recommendations of your vacuum sealer manufacturer, but it’s usually enough to easily slide the end of the bag into the sealer without the food getting in the way. Place the blanched vegetables in the bag and insert the open end into the sealer. Allow it to run through a full vacuum and sealing cycle before removing it. Check the seal before storing to ensure that there are no openings that can allow air in.
Although vacuum sealing keeps some harmful bacteria out, others, like Listeria monocytogenes, thrive in the low-oxygen environment so you must store the vegetables correctly. Keep the vacuum-sealed produce stored at or below 40 degrees Fahrenheit at all times until you are ready to use it. Vacuum-sealed vegetables store safely and with minimal loss of quality for seven to 14 days in the refrigerator, or you can keep them for up to 3 years in a 0-F freezer. When thawing vegetables, do so overnight in the refrigerator so they aren’t exposed to temperatures above 40 F.
References and ResourcesUniversity of Wisconsin Extension: Safe Preserving: Using a Vacuum Sealer
Seal a Meal: Helpful Hints