Many Colorado residents enjoy growing produce in their garden or purchasing locally grown produce for future consumption. It’s possible to have delicious Cedaredge apples and tender San Luis Valley potatoes well into the winter. Proper storage and handling of produce can make it possible. Good food storage practices help preserve the quality and nutritional value of food and also helps cut down on spoilage. Produce may be preserved by canning, pickling, freezing or dehydrating for longer storage.
It is possible to store foods for extended periods of time in spaces that are temperature and humidity controlled. Storage can be done on a small scale, with a limited investment. Basements, insulated garages, and porches can be good options. Unfortunately, storage only works for certain fruits and vegetables, and the amount of time any product can be stored varies. Although some produce may be kept at the same storage temperatures, it’s not always advisable to store all produce together. Some items, such as onions, can give an off-flavor to other items. For best results, store fruits and vegetables separately.
Timing of Storage
A frequent cause of early spoilage occurs when fruits and vegetables are placed in storage before cold weather begins in the fall. One of the most difficult steps in successful storage is to keep the produce in prime condition from the time of optimum maturity until the night the temperature is low enough to cool the storage place. The most complete retention of nutrients will be achieved if the produce can be stored under the proper conditions immediately at harvest. Use fruits and vegetables quickly after taking them out of cold storage; they will not keep as long as freshly-harvested produce. Before spoilage begins in earnest, stored produce can be preserved by canning or freezing. It is best to use the highest quality produce possible.
How successfully your produce keeps depends on maturation, quality, and storage temperature and humidity. Late-maturing produce varieties are best-suited for storage. Products should be harvested at the peak of maturity or close to. Crops should be harvested during dry weather. Do not wash root crops before storing; a thin crust of dry soil helps prevent shriveling. Leave an inch or more of stem on most vegetables to reduce water loss and prevent infection. Crops should be as free as possible from skin breaks, bruises or decay. Bruises and skin breaks are the greatly increase moisture loss. The inclusion of one diseased or damaged specimen can start decay that will rapidly destroy other stored food, or that will taint flavors with mustiness.
Packing materials used in storage perform several functions: (1) insulation against fluctuating temperatures and freezing; (2) moisture retention; and (3) reduction of disease transmission. Use these materials only once, since they may become contaminated with spores or bacteria. Moisture retention of produce is very important, be sure to maintain circulation and prevent condensation. Individual wrapping of produce with newspaper aids moisture retention and reduces the possibility of cross-transfer of odors and disease.
The Best Conditions for Storage
Many fruits and vegetables can be stored for extended periods of time, provided they are stored under the proper temperature and moisture conditions that will not allow them to freeze or complete their natural decomposition cycle. Crops held in storage are living plants that are made dormant by their environment.
Products suited to storage can be grouped according to the best conditions for each:
- Cold (32 to 40 degrees Fahrenheit) and very moist (90 to 95 percent relative humidity);
- Cold (32 to 40 degrees Fahrenheit) and moist (80 to 90 percent relative humidity);
- Warm (50 to 55 degrees Fahrenheit) and dry (60 to 75 percent relative humidity); and
- Cool (32 to 50 degrees Fahrenheit) and dry (60 to 70 percent relative humidity).
The following is a list of temperature and humidity requirement for fruits and vegetables grown in Colorado that are suitable for longer term storage (temp. in degrees Fahrenheit):
Apples: 30-32o; Moist; 2 to 6 months Garlic: 32o; Dry; 6 to 7 months
Beets: 32o; Very Moist; 3 to 5 months Onions: 32o; Dry; 6 to 7 months
Cabbage: 32o; Very Moist; 3 to 4 months Peppers, hot: 50o; Dry; 6 months
Carrots: 32o; Very Moist; 4 to5 months Pumpkins: 50-55o; Dry; 2 to 3 months
Pears: 32o; Very Moist; 2 to 7 months Squash, winter: 50-55o; Dry; 2 to 6 months
Potatoes: 40o; Very Moist; 4 to 9 months Sweet Potatoes: 55-60o; Dry; 4 to 6 months
Storage of Home Grown Vegetables. CSU Ex. Fact Sheet 7.601
Storage Guidelines for Fruits and Vegetables, Cornell Cooperative Extension
Storing Fruits and Vegetables from the Home Garden, U. of Wisconsin Ext. Fact Sheet A3823 http://learningstore.uwex.edu/assets/pdfs/A3823.pdf