Freezing food is one way to preserve your harvest and keep it fresh. The process allows you to reduce the amount of fresh food that goes to waste, and also to ‘lock in’ the nutrients from freshly picked crops. It also allows you to freeze your harvest to enjoy later in the year, when less fresh food is available, so you can eat a more varied diet throughout each and every season.
Food waste is a major problem in today’s world. Commercial food production uses a lot of resources and is a major contributor to our climate crisis. Yet many people do not treat food as the precious resource that it is. Huge quantities of food are wasted each year. As polytunnel growers, we can do our bit by growing at least some of our own food at home. When we do grow food, we can make sure we keep it fresh and avoid waste wherever we can.
To help you keep it fresh, here are some tips on how to freeze your harvest:
Choosing Which Produce to Freeze
Almost everything that you grow can be frozen while fresh. There are, however, a few exceptions. Potatoes, for example, do not freeze well before they are cooked, so it is best to cook them before you freeze them.
When choosing which products to freeze, you should always make sure you choose high quality produce to put in the freezer. Check your harvest over thoroughly to make sure it is not harbouring any bugs or insects. Put any blemished or disease spotted examples aside, chop off affected areas and, if possible, use them more quickly (or add them to your composting system).
Freezing Fresh Vegetables
In order to keep the flavour and nutritional content of the fresh vegetables you are freezing, it is often necessary to ‘blanch’ them. Blanching involves boiling, steaming or stir-frying them for a very short time to till the enzymes that will otherwise continue to decay the vegetables even after they have been frozen.
Not all vegetables have to be blanched. Onions, for example, can simply be chopped up, placed in a suitable container, then defrosted as required.
However, many of the crops we grow should be heated briefly then cooled quickly before they are frozen. Here are some examples of the blanching times for common vegetables (and edible seeds):
- Beans (green/ French or runner) – 2-3 minutes.
- Broccoli (cut into 1 inch pieces) – 2 minutes (longer for larger florets).
- Brussels sprouts – 3 minutes (or a little longer for particularly large ones).
- Carrot (slices) – 2 minutes (a little longer for larger pieces)
- Cauliflower (1 inch pieces) – 2 minutes (longer for larger florets).
- Kale (and other thick leaf vegetables) – 1-2 minutes.
- Peas – 2 minutes or so in pods, 1 minute shelled.
- Spinach (and other thin leaf vegetables) – less than 1 minute.
To blanch vegetables:
Prepare a bowl of ice water (to stop vegetables from cooking immediately when you remove them from the hot water, pan or steamer).
Wash and chop your vegetables.
Blanch your vegetables by beginning the cooking process, but stopping much sooner than you would if you were going to cook them fully.
Remove the vegetables from the cooking receptacle and plunge them into the ice water.
Prepare your freezer-safe containers for your vegetables.
Freezing Fresh Fruits
Fruits do not usually need to be blanched, with the exception of large fruits like squash and pumpkins, which can be cut into inch cubed pieces blanched for 2-3 minutes. Tomatoes, peppers and soft fruits and berries can all be frozen without any cooking/ heating at all. Rub fresh apples and other acidic fruits with lemon juice to stop them browning before freezing. Halve stone fruits and remove their stones/pits.
To prevent the fruits from sticking together and clumping when frozen, and to make retrieval easier when you want to use them, spread them out and freeze them on trays. (The same technique also works well for blanched vegetables). Once they are frozen, transfer them to suitable containers.
Freezing Fresh Herbs
Leafy herbs like basil, coriander and parsley will not respond well to drying. To preserve the fresh herb flavour of these herbs, the best option is to freeze them. There are various different methods which allow you to do so in a convenient way.
One method involves chopping the herbs finely and packing them into an ice cube tray before topping off with a little water (or vegetable stock). You can then simply pop the cubes out of the tray and use them as required later in the year.
Another method is to blend your herbs into a paste with a little oil or water (or make a full pesto) before you freeze them. Frozen cubes can be stored in an airtight container in a freezer for up to 3-4 months.
Do you freeze home grown vegetables, fruits and herbs? Share your tips and techniques in the comments below.
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.