One easy way to cut food costs is to use the freezing method of food preservation. This is a great way to preserve fresh foods and leftovers. Not only is freezing food simple and economical, but there are health benefits, too!
From ancient natural ice storage to today's rapid-freezing techniques, freezing technology has transformed food preservation. Snow and ice cellars were used by early civilizations like the Chinese and Romans. During the 19th Century the “ice box” trade led to home ice boxes. In the 1920’s, Clarence Birdseye invented the “quick-freeze” method. This method was inspired by the techniques of the Inuit, an indigenous people living in Northern Canada and parts of Greenland and Alaska . By the 1950’s, Birdseye had pioneered modern commercial frozen food, making it widely accessible.
Did you know that freezing food offers several distinct health and nutritional benefits? These benefits range from altering the molecular structure of carbohydrates to preserving the nutrient density of produce. When starchy foods like bread, rice, and pasta are frozen, a process called retrogradation occurs, which converts simple starches into “resistant” starch. Because resistant starch is harder for the body to digest, there is a significant reduction in spikes of blood sugar compared to fresh options. Research shows that freezing then toasting bread can reduce its glycemic response by up to 39%. There are also prebiotic benefits to freezing foods. Since resistant starch travels to the large intestine undigested, it serves as a prebiotic that feeds beneficial bacteria to the gut. As a bonus, starchy foods that have been frozen are digested more slowly, which helps us feel full for longer periods of time.
Freezing food also preserves nutrients. Acting as nature’s preservative, freezing locks in vitamins and minerals at their peak, especially when produce is picked at ideal ripeness and “flash frozen” immediately. Flash freezing can be done at home by washing produce and removing all moisture to prevent ice crystals, then placing prepared individual items in a single layer on a parchment-lined baking sheet and freezing for 1-2 hours until solid, then transferring to freezer bags. Freezing fresh local produce is a great option for preserving nutrients. Studies show that some frozen fruits and vegetables like broccoli, spinach, and blueberries frequently have comparable or even higher vitamin content than fresh versions that have sat in the refrigerator over several days.
As with all food preservation methods, food safety should be a top priority. Keep in mind that while freezing food at 0°F (-18°C) or below keeps it safe indefinitely by inactivating microbes like bacteria and mold it does not kill them. Therefore, the main risk is bacterial growth during thawing, not freezing. To ensure safety, maintain a constant 0°F temp, use moisture-proof packaging to prevent freezer burn, and never thaw food on the counter. Proper cooking is also required to kill bacteria or parasites (like Trichina). Also, freezing does not fix food that was already spoiled; it only preserves the quality it had when stored in the freezer. Frozen foods must be thawed safely to stop the growth of microorganisms as the temperature of the food increases. The process of thawing foods safely limits how much time a food spends in the “Temperature Danger Zone” (41°F to 135°F). This temperature range is ideal for pathogen growth. For example, some pathogens will double in number every 15 to 20 minutes in this zone. The risk of foodborne illness increases as the number of pathogens grows. There are four methods to thaw food safely.
Thawing food in the refrigerator is the best method. Using this method, the internal temperature of the food will not increase above 41°F, which should be the temperature of the refrigerator. To thaw food in the refrigerator, place the frozen food in a container to catch any leaks. Set thawing meats on the bottom shelf to prevent leakage onto other foods. Once thawed, use the food within 1 to 5 days. As a rule of thumb, ground meats and fish last 1-2 days, while red meat cuts (steaks/roasts) can last 3-5 days. Poultry should be cooked within 1-2 days. According to ServSafe guidelines and food safety regulations, thawed fruits and vegetables should generally be kept in the refrigerator and used within 24 hours to 3 days.
The cold water method is also a safe method for thawing food. This method should only be used with foods that can be thawed in less than 4 hours. Place the frozen food in a leak-proof container or plastic bag to prevent splashes or leaks that can spread pathogens. Place the food under cold running water or submerge it in cold water. If submerging the food, change the water every 30 minutes to keep the temperature cool. It’s important to note that foods thawed using the cold water method may thaw unevenly. The outside temperature will increase faster than the center. For this reason, it is important to limit the time needed for thawing. When food has thawed, cook it immediately!
The microwave is another safe option for thawing frozen foods. This method is for foods that will be cooked immediately after microwaving. Keep in mind that the microwave can thaw foods unevenly. Some parts can be thawed and heated into the Temperature Danger Zone, while other sections are still frozen. For this reason, foods thawed in the microwave must be cooked immediately after thawing to kill pathogens.
The fourth method of thawing frozen food is to thaw it as part of the cooking process. Some foods can be cooked frozen without impacting quality or taste. To prevent foodborne illness, cook foods to their minimum internal temperature.
Freezing is a great way to preserve your produce! If you would like to learn more about food preservation, contact your local N.C. Cooperative Extension Center. In Richmond County, contact Cheri Bennett at 910-997-8255. The Richmond County Center helps provide research-based education and technology to the producers and citizens of this great county. The office is located at 123 Caroline St. in Rockingham.
