Harvest Time! A Primer on How to Preserve All That Good Food
You put in a home garden and everything came ripe… at the same time.
The tomatoes!
The zucchini!
The green beans!
Or, maybe you went to the Farmer’s Market and got a great deal on a bushel of pickling cucumbers.
It’s all a bit much. Who can eat it all right now, before it goes bad? Sure, there are 100 ways to prepare zucchini but at some point, you’re just sick of it. You don’t want more zucchini now. You want it in February, when all the store produce is bland and tasteless.
So how do you keep it until then?
Food Preservation Options
Freezing
A great option is freezing. However, not every vegetable or fruit is suitable for freezing. Some of them are too fragile, some of them get mushy. Think of the kinds of produce you typically see in the frozen food section - they’re kind of tough, right? Peas, corn, broccoli, potatoes. This toughness is thanks to cellulose, the rigid structure in the plant cell wall. And, it’ll stay rigid during freezing - better for long term storage. If there’s a leafy green that’s frozen, like spinach, it’s been steamed and formed into a block.
When you go to freeze a food, it’ll likely need to be blanched first. You may see this in recipes or in food preservation guides. Blanching means you’re getting that food scalding hot in boiling water for a very quick period of time, followed by an ice bath. This gets rid of the ripening enzymes, so the food doesn’t keep turning on you. It also locks in vitamins and kills off microorganisms that came in on the food. It helps keep the veggie’s texture just a little bit more intact, and helps them last a bit longer in the freezer.
Dehydrating
In dehydrating, we’re encouraging water to leave the food by evaporation. Not all the water leaves (unless you’re doing freeze-drying), so dehydrated foods don’t last too long and the act of drying them (even at low heat) can still degrade some of their more fragile nutrients (like vitamin C and B vitamins).
But, it’s quick, it’s easy, and it does work. I think that dried vegetables make the most sense in soups or stews. So, dehydrate some of the excess bounty you’ve got now and when soup season comes around in a couple of months, you’ll be ready!
Fermenting
This is where we let the good bacteria fight the bad bacteria, and then they make a bunch of lactic acid and that helps keep the bad bacteria at bay (and makes it delicious). What do I mean by all of that? Think of sauerkraut. It’s very thinly sliced cabbage with a lot of salt on top. The salt draws out the water, which then mixes with the natural bacteria on the cabbage.
Over a few weeks, the natural bacteria combines with the existing sugars in the vegetables. A byproduct of this metabolism is lactic acid, which helps prevent spoilage and bad bacterial growth.
Canning
This is where food preservation gets really interesting to me. So interesting, that there will be additional blog posts that dive into the food science of canning even more.
There are two types of canning for food preservation:
Water-bath canning
If a food is high-acid (most fruits), the bacteria that cause botulism can’t grow in it. And as such, it can get sealed in a jar without fear of botulinum toxins. The jarred food just has to get cooked hot enough in a rolling boil for a few minutes and then it can sit in the pantry until you’re ready to enjoy it!
Pressure canning
If the food is low-acid (everything except most fruits), it, unfortunately, can still grow the botulism bacteria, Clostridium botulinum. And that bacteria will kick off botulinum toxin, leading to potential paralysis and death (kind of fun fact: this is the same toxin found in botox injections).
C. botulinum also has another fun party trick: it’s extremely tough. When it notices that it’s under attack, it’ll put up heat-resistant shields called endospores. And it has to get cooked at over 240 F for an extended period of time to bust through these shields. Who remembers the boiling point of water? Only 212 F. So, how do we get above 212 F? We up the pressure! More on this in a future blog post - but for now, just keep in mind that most foods (vegetables, meat, fish, poultry) have to get pressure canned at a specific pressure and for a specific amount of time.
Food Preservation Resources:
TL;DR: Type this into Google: “(food you want to preserve) (method you want to use, like freezing or canning) recipe cooperative extension”
There are a LOT of websites out there with specific guidance on food preservation.
This does not mean that every resource is trustworthy.
In fact, there is a lot of VERY DANGEROUS advice floating around out there with food preservation. And this is something I deeply care about, because while it may seem like a fun or whimsicle hobby, it can turn deathly serious in an instant.
So, to combat this, when I am looking for a new recipe (or trying to refresh my memory on an old one), I always use resources from a university’s Cooperative Extension service. They publish verified recipes that have been tested against scientific rigor to make sure they keep you safe.
Here’s an example: let’s say I want to make my own beef jerky.
I go to search “beef jerky recipe” and I’m faced with page after page of this blog and that site and this post and that page. It’s confusing, I don’t know if anyone really knows what they’re talking about, but I do know that I’m about to be handling raw meat and not really being sure if it’s getting cooked.
So, instead, I search “beef jerky recipe cooperative extension”, and the first link that comes up is from the mothership itself: University of Georgia’s National Center for Home Food Preservation https://nchfp.uga.edu/how/dry/recipes/jerky/.
Can I tell you how relieving it is to know that this page won’t lead me astray? It has no ulterior motives. It just wants to help you make homemade jerky and not get sick.
Have Fun With It!
So get out there and try some home food preservation! And let me know what some of your favorites are, and what others should try next.
