Canning vs. Fermentation
What’s the difference between canning and fermentation? There are a lot of differences, and in many respects the processes are actually opposites! In some other senses, though, they are more similar than you might think. If you’ve added vinegar to vegetables and let them sit, you’ve made quick/refrigerator pickles. If you’ve added hot vinegar and spices to vegetables and then boiled them in a hot water bath, you’ve made canned pickles. If you’ve poured salt brine over vegetables or mixed salt in with finely chopped vegetables and let them sit at room temperature for several days to months, you’ve been fermenting your vegetables.
How do they do?
- From a technical perspective these processes have very little in common. Canning is the process of thoroughly sterilizing your vegetables so that no bacteria, bad or good survive. A long enough boiling bath and enough added acid will prevent dangerous bacteria like C. botulinum from successfully spreading its hatred and death, but it will also kill off all of the friendly lactic acid bacteria and other helpful or neutral microbes that were previously present and ready to reproduce.
- Fermentation is the process of cultivating an environment in which good bacteria can survive and thrive. Those bacteria in turn create an environment in which bad bacteria simply cannot survive. They do this quite well and with very little human intervention. I like to say that lactobacillus and clostridium botulinum are natural enemies, and in their battles, the good guys always win (and the good guys have an undefeated record for thousands of (probably more) years when it comes to sticking it to bad guys in vegetable fermentation).
- Canning is pretty close to permanent. Canned goods will vary very little in taste/texture/acidity/etc. from the day that you stick them in the pantry. They will degrade in quality over time (like a year or more), but they will definitely not be drastically different from one week to the next. If you’re storing food in your bunker, this would be your method of choice.
- Fermentation is ever-changing. Fermented foods will frequently change daily and over time they will vary drastically in taste, texture and acidity. A three-month-old ferment can be almost a completely different food than its three-day-old counterpart. Aging fermented foods is part of the fun!
- Canning is safe. With modern knowledge and practice, risk of any harm from canning is negligible. There was an historic risk of botulism which remains today if the basic principles are not followed. Use a trusted resource for recipes and follow them exactly.
- Fermentation is safe. Fermentation has existed forever specifically as nature’s way of making foods safe to consume well after the harvest. There are no reported cases of botulism from vegetable fermentation (EVER!) and the risk of eating raw foods is significantly lowered by the changes that occurring during the fermentation process. Understand the basic principles and feel free to experiment wildly.
- (Opinion) Canning can be laborious. A big ol’ canner lives in my basement. It takes up a whole shelf. It once took 3.5 hours on my friends electric stove to get the water in it to a boil. The vast majority of this laboriousness comes from scale. When actually using it to preserve the harvest, oh my lord, you can be in the kitchen over a hot stove for a full day. Not my cup of tea, especially in the summer. When working in smaller batches, this criticism obviously lessens a great deal.
- (Opinion) Fermentation is easy. When we’re talking veg fermentation, it’s usually as easy as chopping something and putting it into a jar or crock or and adding salt and seasonings. The only difficult part is waiting for them to be ready.
- Canning has the benefit of being a very long lasting preservation method AND, when you can, you can preserve fruit quite easily. Fermenting fruit without a starter will get you wine! Canning fruit will get you jam, conserves or preserves.
- Fermented foods have many intrinsic health benefits; far too many to recount in a bullet point! Important points: they are probiotic foods, they have a higher vitamin and mineral content than their raw or cooked counterparts, they are more digestible than raw and cooked vegetables. That doesn’t begin to cover it, but hopefully that little tip of the iceberg gives you a hint as to how special and healthful fermented vegetables are! To my knowledge there are no specific health benefits associated with canned foods.
- Canning is nearly immediate gratification. Although you would most likely want to hold off on eating it all if you’re seriously preserving food for the winter, canned foods are generally good to be eaten immediately or within a few hours or, at most, days of canning.
- Fermentation is delayed gratification. With a few exceptions (bread and yogurt come to mind, and even then there is some delay), you generally have to wait before these guys are ready to eat. Waiting can be a day (kefir), weeks (pickles) or years (miso, soy sauce, wine, etc). While the actual making of many of these foods is a pretty quick process, the hands off part (aka fermentation) can take what feels like forever when you’re salivating over an intensely-scented jar or crock. Protip: Hide your long-aging ferments from yourself and set a reminder on your phone. It’s the whole “watched pot” thing.
I realize that this perspective may be controversial, and that it is definitely controversial amongst the more virulent “anti-canning” factions of the fermentation world, but I believe that these two practices are often quite aligned in spirit. Both methods are focused on improving the food culture in which we live. Both practices are old practices that take responsibility for the processing of our food and eschew the industrial food system which is thrust upon us and our planet, taxing our bodies, our resources and our soil.
I think preserving the harvest, in whichever way we choose, is a political act. I think it’s rebellious to can. I think it’s rebellious to ferment. Both practices take a stand against Lucky Charms and Lean Cuisine. Both practices permit us to actively move away from the idea of food as convenience and towards the understanding that food is culture and culture takes time to build and is worth protecting. Both traditions remind us of the importance of sustainable agricultural practices. I don’t think there are many canners out there set on eradicating all the bacteria in the world. The fact that their process is one that kills off the naturally present good bacteria is just how it is. It’s a different choice and it does different things.
Obviously, I prefer fermentation (you might have noticed that this isn’t a canning blog). The health benefits of fermentation are important to me, and I think rejuvenating our depleted microbiomes is societally important. I also think there is no comparison to the taste of fermented vegetables. But I don’t assume that my preferences are everyone’s. I don’t assume that people who have long winters and need local vegetables in late February will be happy with only vegetables and no fruit. I think there is room for both practices and that canning has its own, important role in food preservation.
In short, canning and fermentation are not the same thing. They may look the same, but they don’t taste the same and they need to be made, stored and eaten differently. However both processes have value and can serve as excellent ways to preserve the harvest and tell the (grocery store) man that GMO foods shipped in from factory farms thousands of miles away are not for us!