Michigan
State University Extension
Preserving
Food Safely - 01600513
10/13/97
The best vegetables for freezing are fresh, tender and
straight from the garden. The fresher the vegetables are
when frozen, the more satisfactory the frozen product.
FIRST STEPS
Wash vegetables thoroughly in cold water. Lift them out
of the water as grit settles to the bottom of the pan.
Sort vegetables according to size for heating and packing
unless they are to be cut into pieces of uniform size.
Peel, trim and cut into pieces, as directed for each
vegetable.
HEATING BEFORE PACKING
An important step in preparing vegetables for freezing is
heating or "blanching" before packing. Practically all
vegetables, except green peppers, maintain better quality
in frozen storage if blanched before packing.
The reason for blanching vegetables before freezing is
that it stops the action of enzymes. Up until the time
vegetables are ready to pick, enzymes help them grow and
mature. After that they cause overripening, loss of flavor
and color changes. If vegetables are not sufficiently
blanched, the enzymes continue to be active during frozen
storage. The vegetables may develop off-flavors, discolor,
or toughen so that they may be unappetizing after a few
weeks of freezer storage.
Blanching also wilts and softens vegetables which makes
them easier to pack. Blanching time varies with the
vegetable and size of pieces.
To blanch
For home freezing, the most satisfactory way to blanch
blanch vegetables is in boiling water. A blancher, which
has a blanching basket and cover will make the job easy. A
wire basket fitted into a large kettle (and lid) will
substitute for a blancher.
For each pound of prepared vegetables, use at least 1
gallon of boiling water in the blancher or kettle. Put
vegetables in a blanching basket or wire basket and lower it
into the boiling water. A wire cover for the basket can be
used to keep the vegetables down in the boiling water.
Put the lid on the blancher or kettle and start counting
blanching time immediately. Keep heat high for time
given in directions for vegetable you are freezing.
COOLING
After vegetables are heated they should be cooled quickly
and thoroughly to stop the cooking.
To cool blanched vegetables, plunge the basket of
vegetables immediately into a large quantity of ice cold
water. Change water frequently so that is stays ice cold.
It will take about as long to cool the food as it did to
blanch it. When the vegetable is cool, remove it from the
water and drain thoroughly.