Question 1

Does Freezing and Blanching Cause Nutrient Loss?

Accepted Answer

A little, yes. Anytime you boil vegetables or put them in water, there will be some loss of water soluble vitamins. In most vegetables that means some loss of Vitamin B and Vitamin C. On the other hand, fat-soluble vitamins like Vitamin A and K become a little more concentrated. Does this mean you shouldn’t freeze or blanch vegetables – no! It means you should eat a variety of vegetables, some raw and some cooked. If you have a well balanced diet, this minimal loss of nutrients is nothing to worry about.

Question 2

Does Blanching Kill Bacteria?

Accepted Answer

Yes and no.

Boiling kills most bacteria. But, because blanching is not a very long boil, not all bacteria or their spores may be destroyed. Some bacteria need to be kept at 165°F/74°C for 10 minutes or more to be destroyed.

Question 3

Does Freezing Kill Bacteria?

Accepted Answer

No. It does "freeze" or stop bacteria, mold and yeast from actively growing, but it does not kill them. Once food is thawed, those microbes become active again. Freezing only suspends their activity. If you blanch before freezing, you will kill most bacteria.

Question 4

Can You Freeze Vegetables Together with Other Vegetables?

Accepted Answer

Yes, you can. If you want to make your own medley of frozen vegetables here are two ways you can do so:

Blanch and Freeze Together - If your vegetables are approximately the same size and require the same blanching time as indicated in the chart, you can blanch and freeze them together.
Blanch and Freeze Separately then Combine - If the vegetables have different blanching times, blanch them separately and then pack them together in freezer containers.

I usually do not freeze vegetables together because I like the flexibility to pick and choose which vegetable to add to a dish. Also, I freeze vegetables when they're in season and my favourite combination of peas, carrots and corn are never ripe at the same time.

Freeze veggies together if you know you'll LOVE to eat them together EVERY time and they have the same blanching times. To keep your options open, freeze veggies separately.

Question 5

What is Flash Freezing Vegetables?

Accepted Answer

In home kitchens, flash freezing is when we spread vegetables in a single layer on a large tray to quickly freeze them as individual vegetables. This prevents vegetables from sticking together in one large clump and, because they freeze more quickly, there will be fewer and smaller ice crystals. After about an hour of "flash freezing" vegetables are put in an airtight container for long term storage.

Flash freezing corn at home so it freezes quickly and I can easily pour out just what I need without it being all stuck together.

Commercially, flash freezing is a much more intense process. Fresh produce is frozen very quickly at extremely cold temperatures by submersing the vegetables in liquid nitrogen. The result is instant frozen veggies with minimal ice crystals.

Question 6

How Long Will Frozen Vegetables Last?

Accepted Answer

Your frozen vegetables will be safe to eat as long as they stay frozen at a consistent -18°C/0°F. But for best flavour, rotate through your frozen vegetables regularly and use within 6-12 months. Don't hoard them, eat them!

Question 7

What Kind of Containers Should I Use to Freeze Vegetables?

Accepted Answer

Use freezer grade containers that are moisture-vapor resistant, durable and easy to seal.
Use correct size of containers that fit food snuggly and avoid having extra air space.
Freeze in small portions.
Provide sufficient headspace to allow for expansion if food contains liquid and you're using glass or plastic containers.
Options include:
- Rigid containers – plastic, tempered glass, aluminum
- Flexible containers – silicone bags, freezer bags, freezer wrap, freezer paper or foil
- Ice cube trays – for small servings
Label packages – food, date, quantity and any other info to help you use your food efficiently

Question 8

Can I Reuse Plastic Food Containers to Freeze Food

Accepted Answer

Reusing plastic containers (yogurt or margarine tubs) is a great way to practice sustainability in the kitchen. They may not be as airtight as other containers, so use these for foods you'll eat within a few weeks. And remember, label well so you remember what's in them!

Question 9

Do containers need to be sterilized when freezing food?

Accepted Answer

No. Just use well cleaned, airtight containers.

Question 10

What is freezer burn?

Accepted Answer

Freezer burn is a food quality, not food safety issue.
Occurs when moisture moves from food and refreezes on the inside of the package, leaving food with dry patches and a package full of ice crystals.
Dry, grayish-brown spots on food are known as freezer burn and typically are accompanied by ice crystals in the frozen food package.
Caused by excess moisture, exposure to air and/or frequent temperature fluctuations.

See below for tips on how to prevent freezer burn.

Preserving

How to Blanch and Freeze Vegetables – A Handy Guide

How to Freeze Onions and Why It’s a Good Idea

How to Make Cranberry Fruit Leather

Pickled Red Cabbage with Carrots and Cilantro

How to Can Applesauce – Hot Water Bath Canning

Ten Steps to Quick Refrigerator Pickles – No Canning Needed

Three Types of Strawberry Jam – Freezer, Low Sugar, Classic

Common Questions about Pressure Canners and Pressure Cookers

How to Harvest Mint – Prune, Dry, Enjoy Your Mint

How to Blanch and Freeze Spinach

Finishing Salt – Making Your Own Flavoured Salts

Canning Food – When to use a Hot Water Bath or Pressure Canner

Thank you!