Packaged Food Science

Why Canned Foods May Be More Nutritious Than The Fresh Stuff

When it comes to comparing fresh food versus canned food, one of the starkest differences between the two has to be shelf life, or how long a product can last. Most produce and meats won’t stay fresh more than a couple of days, even in the fridge or after being cooked. They’ll begin to lose flavors, change texture, and eventually spoil. Canned food, on the other hand, won’t change at all over the course of months, or in some cases, even years.

Of course, this leaves the question of how canned goods can keep for as long as they do without going bad. This has led to a number of misconceptions about the entire industry, including that they use a plethora of preservatives (not really) and are less healthy than their fresh counterparts (in some cases, canned food may actually be healthier).

Once you understand how canning works, though, it may open your eyes as to how the shelf-stable food is not only good to eat months after its made, but also why it may be, in some cases, a more nutritious option than consuming fresh food.

The History and Science of Canning

The process of canning was first invented in the early 1800s by French chef and candymaker Nicolas Appert. He developed canning as a way to preserve food using heat that won a prize from Napoleon Bonaparte, who was looking for a novel way to feed his troops. Appert first started by sealing foods in glass jars with wax. This was later shifted to tin cans, the basis of modern canning operations today.

Appert’s process was a form of sterilization, only instead of using chemicals (which is what many people recognize it as today), he was using heat to kill bacteria. This was similar to what Louis Pasteur did in 1864 when he invented the pasteurization process used in milk and juices, but Pasteur was looking to just kill pathogens, or disease-causing microbes. Other bacteria, including those that didn’t need oxygen (called anaerobes), could still grow and multiply over time.

Where Appert’s process differed was in that he used an airtight environment, as well as a greater amount of heat. This combination meant that bacteria and other spoilage microbes inside would be killed and unable to regrow. One of the biggest threats came from anaerobic bacteria that produce heat-resistant spores. The type of sterilization in canning uses enough heat to prevent these spores from ever having the chance to grow and multiply.

All of this happened without the need for preservatives that go into products like packaged cereals and other shelf-stable foods. While some canned products contain salt, sugar, or acidic products like vinegar, these are meant more for flavor, color, and texture than they are for the preservation properties they often have in foods.

Sterilization does also cook the food inside, meaning that textures will change as a result.

How Canning Changes Food

Today, canning has evolved to utilize more sturdy packaging and scientifically-controlled heat. Food processors use enough heat at an appropriate time needed to kill the requisite bacteria or spoilage organism in question. Scientists target specific microbes for each food based on its acidity, moisture content, the heat resistance of the target microbe, and other factors.

More than just keeping bacteria from spoiling food over months, though, canning has other benefits. One of the biggest is that food preserved by canning is often sterilized straight from being harvested. Over time, the nutritional and sensory qualities of food decrease over time when exposed to a normal environment. This means that technically, a peach that’s been on the shelf for a couple weeks has less available nutrients, flavor, and color than one picked fresh from the tree. Compounds naturally break down over time, so this is natural.

In canning, however, food is preserved much closer to the harvest point, and are subject conditions (including that airtight seal) that prevent degradation from occurring as fast. Thus, nutrients may be more available from a canned food compared to the fresh version in grocery stores. That’s not true for all nutrients, however. Some water-soluble nutrients like Vitamin C and some B vitamins, leach into water surrounding the food or are destroyed by heat while the food is sterilized. You’ll see a decline in these nutrients overall when cooking, regardless of process.

The next time you’re looking at purchasing canned food and judge it for being “lower quality,” as its often perceived, you might want to keep the above in mind. More often than not, canned food is just as nutritious as the fresh variety and can last a lot longer without the need for preservatives.

Information used in this article was obtained from: 

Fellows, P. J. (2009). Food Processing Technology: Principles and Practices, 3rd Edition. Cambridge: Woodhead.

Packaged Food Products Science Video

Here’s How 10 Of Your Favorite Processed Foods Are Made

A processed food is any food item that’s been converted from a raw ingredient (like wheat, corn, or soy) and turned into a food product (like bread, corn syrup, or tofu). We’ve all eaten our fair share of processed foods over the course of our lives. They crowd the shelves of our grocery stores and supermarkets, where we see them, recognize them as tasty or nutritious, and consume them. But if you’ve never been to the factories that produce items like cookies and chips by the thousands, you’ve probably never seen how these go from raw ingredient to supermarket shelf. Hopefully, after reading this article and watching these videos, you’ll have learned how some of the more common processed foods out there are actually produced.

American Cheese

American cheese has long had a reputation as an inferior cheese product that people shouldn’t be eating. However, as explained above by HowStuffWorks, it was actually developed as a novel way to reconvert cheeses that wouldn’t sell into a usable piece of dairy that we all enjoy as Kraft singles and the like today. We should be thankful that American cheese has evolved the way it has now, because it helps the rest of the cheese industry fight against food waste.

Toaster Pastries

Whether you had Pop Tarts growing up or some of the other popular frosted toasted pastry brands, these were a childhood breakfast staple. The combination of buttery pastry and sweet filling with a thin layer of glaze made us all fall in love with this humble but tasty on-the-go meal, and I’m glad it’s still around today. Watching it get made in this old Discovery channel video is pretty cool as well, especially when you discover what frosting’s dual purpose is for these delectable sweets.

Orange Juice

Orange juice is just about as synonymous with breakfast as coffee or eggs, so it’s important to understand what really goes into making this popular beverage. As shown in the above Discovery video, it takes a lot of oranges (and a lot of wasted pulp) to make a carton of OJ, which means we ingest a lot of sugar that naturally comes from the fruit in each glass. There’s also another way to make the juice not shown in this video where water, concentrated juice (juice that’s been boiled down and frozen to preserve it), and copious amounts of sugar are mixed together. Fresh squeezed orange juice isn’t as sugary as this version, but it can come pretty close. Enjoy this sweet citrus nectar, but also ensure that you drink in moderation.

Soy Sauce

A lot of work goes into making this ubiquitous salty condiment that we can find in the Asian section of most grocery stores. Soy sauce has to be fermented for quite a while to achieve the flavor profile we expect, and it’s definitely a bit of a pain to make. Salute to everyone out there who works in the soy sauce industry, ’cause based off of Discovery’s video, this looks hard.

Parmesan Cheese

This savory, salty, and nutty cheese is often found on top of pasta dishes or integrated into pestos, and man, do we love it here in the US. Making this beloved cheese requires a lengthy amount of fermentation and a TON of milk, but the final product is absolutely worth it. Side note: as shown in National Geographic’s video above, this cheese actually isn’t vegetarian since it uses rennet — an enzyme naturally occurring in a calf’s stomach — to separate the curd and the whey. Vegetarian sources of rennet do exist, but you should check your cheese beforehand to ensure you’re not eating the kind that comes from a calf’s stomach.

Canola Oil

Did you know that there’s no plant called “canola?” While the Discovery video above calls the plant canola, it’s actually called “rapeseed,” which probably explains why people wanted to change the name so badly. Regardless, the seeds make an excellent oil that is cheap and easily found in grocery stores all across the nation. If you’ve ever wondered where canola truly comes from, this video’s got all the answers for you.


Not everyone out there may be a fan of tofu, but this soy curd has been a protein staple for many cultures for several generations. Nowadays, we’ve perfected the method at the industrial scale to crank out tons of tofu blocks daily. It’s definitely not the most natural of curdling methods, as the above Discovery/Science video shows. But hey, how we process tofu today gives it a ton of calcium, so that’s always a plus.


Honey may come from bees, but it’s hard to figure out how a company can produce so much at a time. Well, thanks to the above Discovery clip, we can all see how factories take honey combs from beekeepers they contract with and convert the fruits of their labor into bottles of the delicious, runny honey we all know and love. It’s definitely a much better method than over a century ago, when bees would have to be killed before we could break into their hives and steal their honey. Now, we can have our honey and prevent bee populations from getting even more dangerously extinct.

Tapioca Pudding

Man, did I love tapioca pudding as a kid. Made with chewy pearls that were processed from the root of a cassava tree, these sweet treats have become wildly popular as a sugary snack or dessert option for younger kids and kids at heart. Watching it get made in Discovery’s video above is absolutely mesmerizing, and also kinda making me crave some tapioca pudding right now.


Like any other fast food item, McDonald’s chicken McNuggets are shrouded in controversy as to what they actually are made of. Many people still believe they’re made with pink slime, the beef byproduct made by many establishments to lower the cost of ground beef while making it healthier. As Mythbuster Grant Imahara shows, it’s not the case. You can take a look inside one of the Tyson factories that makes McDonald’s nuggets  in the above video if you need to see it to believe it.


What’s Really Inside a Slim Jim [Watch]

Slim Jim

No matter where you live, chances are you’ll spot some Slim Jims in your local checkout line. They’re the classic American meat stick snack, but have you ever wondered — what’s inside one of those things?

It’s time to face reality, folks. The “meat” part of Slim Jims is ground up, very low grade meat. It’s also filled out by “mechanically separated chicken,” aka the pink slime McDonald’s supposedly doesn’t use in their nuggets. And that’s not all — Slim Jims are full of corn, wheat and soy proteins as well as lots and lots of salt. Sodium nitrate can also be found in there, preventing botulism and keeping the meat stick an appealing reddish color.

Check out all the, er, appetizing details in the video below:

Still not grossed out? Then whip up some Slim Jim meatballs ya fool.

H/T Wired + Picthx Facebook