The Process of Preservation and Packaging

How do we preserve our food.. and why do we do it?

Quick Glance: That's A Waste...

The Environmental Protection Agency (EPA) suggests that Americans toss out 35 million tons of food each year. That means we are wasting a lot of food. Much of this food does not contain preservatives which are additives that are used to preserve or extend the shelf life. When we can extend the shelf-life of products, we reduce the need to throw out as much food. There are two commons ways that we preserve food, chemical additives, and physical preservation methods. Consumers may use similar techniques as food manufacturers but just on a much smaller scale. No matter which processing technique is used, additives play a significant role in the American food supply to extend the shelf life of food and keep it safe.

Explore: What Happens In Food Storage?

Food spoilage, food borne illness, and transmission of harmful microorganisms have always been recognized as hazardous. Depending on the food type, preservation can inhibit the growth of harmful pathogens for safe consumption. Food preservation methods have been utilized since ancient times, from drying and fermenting to the more modern methods of canning and freezing, the ability to harvest and preserve food is a key aspect of human survival and life.

Food Preservation is basically done for three reasons:

To preserve the natural characteristics of food
To preserve the appearance of food
To increase the shelf value of food for storage

Categories of Preservatives

There are two categories of preservation: chemical and physical. When you wash your raw produce or freeze your chicken, you are practicing physical preservation. Curing and pickling are examples of chemical preservation, using salt and vinegar (acetic acid) in these cases. Foods are often processed in a way that acts as a physical preservative to guarantee we have safe foods that last longer.

The presentation below covers many of these methods.

Chemical Food Preservations

As you have seen in the presentation above, there are several ways to preserve food. Some of the more common ways that we preserve food is by using additives or more chemical types of preservation. Chemical food preservatives have been used for a long time and they seem to provide long shelf life.

Use the tabbed interactive below to learn about the different types of food preservatives.

Beyond the Chemicals

Beyond chemical preservatives, Native Americans are noted as using some of the first antioxidants to preserve food. They mixed blueberries and meat together to help prevent the meat from going bad. Antioxidants are a natural food preservative that act as a free radical scavenger. Vitamin C is a great example of a natural preservative that falls into this category. Ascorbic Acid (Vit C) is used to preserve jellies and jams, canned fruits, and even boxed cereal. Another type of common natural preservative are spices and herbs. Europeans have been using rosemary for years to help persevere oils and butters. Most of these herbs are recognized as “generally safe” by the FDA.

Preparation for Preservation

As you might know, you can’t just stick some fruit in a can and fill it up with water and seal it. There are a few steps that are missing. Many food items need to undergo a few processes before they can enter the preservation stage.

The graphic below demonstrates some of the processes that are used to prepare fruits and vegetables for the preserving process.

Commercial Methods of Preservation

As mentioned in the slide show above, there are several different processes that manufacturers use to preserve foods to make them safe. Due to insects, diseases, and bacteria, these methods are necessary to guarantee our food supply. Another popular method not mentioned is irradiation. Irradiation has been popular for years. This method uses heat rays to kill potential harmful pathogens in food.

Check out this presentation below. I bet you have consumed a food product that was treated by this process.

Food irradiation calls for shining beams of energy, such as X-rays, gamma rays, or electron beams, onto food because it destroys bacteria that can cause food poisoning; it neutralizes insect pests in food consignments; it maintains food quality by destroying spoilage organisms or suppressing sprouting, and it protects packaged food from microbial and insect contamination.

Watch the video below to learn more about food irradiation.

Challenge

So do you think you understand food additives? Try the challenge below to test your knowledge.

Takeaway: Yum...Nitrates

Are you eating Nitrates in your food?

There is a good chance you are. Nitrites and Nitrates are commonly found in food and are naturally occurring compounds. They have both been added to the WHO list of probable carcinogens. What is the difference? Nitrites are commonly found in smoked meats like pepperoni, bacon, and deli meat. This is a common preservative that acts to keep meat shelf safe for extended periods of time. A study suggested that elevated levels of these were dangerous. So, the FDA has limited the amount that manufacturers can add to meat.

You don’t eat meat?

Well, plants are to blame for much of our nitrate consumption. It leaches in from the soil into our food supply. We eat fruits and vegetables so therefore we ingest the nitrate. So, if you have seen labels in the grocery store that suggest food is “nitrate-free” then it was made by adding this chemical. It is probably not a smoked meat item. The jury is out on the danger of these items. There are suggestions that we need a certain amount and studies suggesting it can be a carcinogen. We will be hearing more about the controversy over these two chemicals in the years to come.

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