Thursday, June 25, 2009

Get the Best Results Freezing Your Garden Produce

By David Burton
University Extension

For gardeners that want to preserve their fresh home-grown produce but don’t want to can them, freezing is a viable option.

“Freezing food is easy and not nearly as time-consuming as canning. In most instances color, flavor, and texture are also maintained when produce is frozen,” said Tammy Roberts, nutrition and health education specialist, University of Missouri Extension.


Blanching is necessary to inactivate enzymes and for freezing success.

“The enzymes are proteins in the plant that help with the ripening and maturing process. If produce is not blanched, this maturation process can continue (at a very slow pace) in the freezer,” said Roberts.

To blanch vegetables, they are placed in boiling water or steamed for a given period of time and then placed in ice water.

To find out exactly how long each vegetable needs to be blanched download the MU Extension guide sheet on “Freezing Vegetables” at

“Blanching for the correct amount of time is important. Over-blanching can result in a cooked product with less flavor, color and nutrients. Under-blanching can actually speed up enzyme activity making the food undesirable for eating,” said Roberts.


The goal with freezing produce is to have the smallest ice crystals possible. To achieve this, the food needs to be frozen quickly.

“When foods are frozen quickly, there is a large number of small ice crystals. Small ice crystals cause less damage to cell walls,” said Roberts.

To assure quick freezing, many people set the freezer at -10 degrees Fahrenheit 24 hours before they are going to freeze food. Once the food is frozen the thermostat can be set back at 0 degrees.

“Do not to overload the freezer with unfrozen food. Overloading will result in slow freezing which makes larger ice crystals and more cell damage. Add only the amount of food that will freeze in 24 hours -- about two to three pounds of food per cubic foot of freezer space,” said Roberts.

For best results maintain a temperature of 0 degrees Fahrenheit in the freezer. Quality deteriorates quickly at temperatures above zero degrees.

For example, the same loss of quality of frozen green beans stored at 0 degrees for one year will occur in three months at 10 degrees, in three weeks at 20 degrees and in five days at 30 degrees.

Ten months is the recommended freezer storage time for fresh vegetables.


For more information on nutrition issues, go online to or contact Tammy Roberts at (417) 682-3579.

The MU Extension program in Greene County is also hosting a “Freezing Your Garden Produce” class on July 16.

Participants will get answers to freezing-related questions, see a freezing demonstration, taste some freezer friendly recipes, and also learn about blanching, packaging, containers, freezer burn, food safety and saving money. Each participant will also receive a free salad.

Registration information is available at or can be obtained by calling (417) 862-9284.

No comments: