In order to meet supply chain demands, businesses need to find ways to preserve perishable items. American companies have been using chemical preservatives for years. Some chemical preservatives have been linked to causing various health effects in young and old. Over time, consumers have become more health conscience and desire chemical free forms of food preservation. Below are four methods of food preservation that do not require chemicals.
Pickling
Pickling has been used as a form of food preservation for thousands of years. Pickling began 2030 BC when cucumbers brought from India began a tradition of pickling in the Tigris valley. Pickling is done by fully immersing a vegetable or fruit into a salt or vinegar bath.
While the produce is in the brine, the fermentation causes lactic acid to develop within the container. The high acidity slows spoilage from occurring within the container. Sailors and Pirates used pickled foods for storage on the water.
Pickling is as useful today as it was back then. Supermarkets have entire isles of pickled foods. Everything from pickled quail eggs to pickled ghost peppers can be found. Glass jars are used for the majority of pickled foods. The high acidity levels can react to metal containers and some plastic containers.
According to the food network, sealed jars of pickles can last up to a year. Unsealed pickled produce can last up to 3 months. The simple ingredients used for pickling have been a proven way to safely and naturally preserve food for eons and should not be overlooked by anyone looking for natural food preservation.
Canning
Commercially canning uses hermetically sealed containers to package and store perishable foods. Microorganisms are greatly reduced with the use of heat to extend food shelf life. Not all commercially canned foods are free of microorganisms, but they are greatly reduced.
Canning was invented as a way to store food for troops during the Napoleonic wars in France. The French government offered a reward to someone that could offer an inexpensive way to preserve large amounts of food. After years of testing, Nicholas Appert recognized that canning operations needed to have cleanliness and sanitation. Appert also recognized the proper heat is needed for canning and sealed containers to prevent foods from spoiling. The original sealed containers used were corked glass.
Canning is still a very popular method of preserving foods. Today most cans are made from steel. A can seamer is used to seal and close cans after a filler has inserted the products into the can. Today, high speed seamers are capable of sealing up to 2000 cans per minute.
According to the USDA, canned foods can keep well beyond the expiration date on the can. The USDA website states that low acid foods such as: canned meat, poultry, fish, potatoes, and green beans can be stored for 2 – 5 years. High acidity foods such as: juices, fruits, and tomatoes can be stored for 12 – 18 months.
Freezing
With modern day appliances, freezing is a simple and effective way to naturally preserve food. The use of freezer storage slows the growth of microorganisms to delay food degradation. Commercial freezing operations use several methods to quickly preserve the quality of the food being froze.
Most commercially frozen foods use flash freezing to better preserve food quality. A rapid freezing process can be done in minutes or less. This rapid freezing is far from the freezing done years ago by natives in cold climates. Foods were stored in clay containers under frozen ground.
Now, commercial freezing operations have multiple methods for quickly freezing foods. An air blast freezing tunnel uses frozen air to blow onto foods as they continually pass through the tunnel on a conveyor belt. Another popular flash freeze method is placing foods in an environmental chamber that uses frozen air to quickly freeze foods.
The USDA states, frozen foods last indefinitely without going bad. Recommended storage times are for quality. One of the biggest enemies in frozen food is freezer burn. Freezer burn causes a loss of moisture in the food, greatly degrading quality. In a previous blog post we described how vacuum packaging can help prevent freezer burn. With the right packaging, frozen foods can last for years in storage while still maintaining high quality.
Vacuum Packaging
Vacuum packaging is an easy and natural way to reduce oxygen within a package to extend shelf life. The reduction or absence of oxygen slows food degradation and increases storage time. Commercial vacuum packaging can use more than air removal to help preserve food items. The use of gas flush can add gases into to packages to reduce or eliminate oxygen content.
One of the most popular gases used is nitrogen. Nitrogen makes up 78% of the air we breathe. A rush of nitrogen into a container pushes oxygen out and leaves nitrogen in the package. A combination of the right levels of nitrogen and oxygen can increase food storage life exponentially.
The potential of vacuum packaging was noticed in 1821 at Montpellier in France. A professor noticed harvested fruits use oxygen and release carbon dioxide. Fruits placed in an atmosphere deprived of oxygen did not ripen as quickly. It would be another 100+ years before vacuum packaging was used commercially.
The most common vacuum packaging machines are nozzle and chamber sealers. Nozzle sealers use a nozzle inside of the package to remove oxygen. Most home use sealers are nozzle vacuum sealers. Vacuum chambers use negative air pressure to create an air vacuum around the package to force oxygen out.
Using vacuum packaging to remove or reduce oxygen content can greatly increase product storage life. The use of vacuum packaging with refrigeration or freezing can allow products to last for years in storage. Food Saver offers a great visual chart to show how cold storage with vacuum packaging can increase product storage times.
Conclusion
All four methods listed above are great alternatives to chemical preservatives. The food being packaged will help determine the best natural preservation method. Some products can be preserved using more than one of the methods listed above or combined methods. Research and experiment to find which offers the longest shelf life, preserves quality, and provides the best look for your product.
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