Tag Archives: canning

Ice or Tin?

Kate and I tend to rekindle a debate every year when Autumn and Winter make their way across the equator and fare at farmers’ markets begins to come from the Southern hemisphere. I like the eat local thang when convenient and usually when possible at all. So we go on about the better way of preserving foods during times when they may not be easily grown.

Freezing is one option and has many advantages. It is usually very easy to freeze food with modern, domestic refrigeration equipment and that equipment is somewhat inexpensive to those of us fortunate enough to live in countries like the United States, Italy, Japan, Brazil, or Australia. A little soak in vinegar, hot water, soy or teriyaki sauce, or treatment with ascorbic acid (vitamin C) may be needed, but usually:

A few spare minutes
Optional preparations
+   Space in the freezer

Frozen food

Freezing can be easy. Is it efficient? I mean that in several ways. Mainly, does freezing maintain taste, texture, and is it affordable to our wallets and our possible futures?

I don’t like thinking about how many joules are used to keep packages of peas and ears of corn suspended in water ice from their point of freezing until they are cooked in a consumer’s kitchen. How much of a drain is it on a town’s power grid with such a packaging plant down the street? How much fuel is burned in transit just to keep frozen food cool? What do grocers pay in the way of their electric bills? How does all of that translate to local, state, national, and global economics? I won’t pretend to understand how power companies and energy trading works but I wonder.

Leaving those crunchy worries aside, freezing is a change in matter states. Flesh that is frozen has a different structure than flesh sold fresh. Water within frozen flesh expands and then contracts when thawed. Cell walls pop. Most of you likely know the science so I won’t insult or bore you with the molecular details. My point is that the texture of frozen foods will often be at least a little, if not noticeably, different. The taste and texture of what I stuff in my maw matter a lot to me.

The time involved in thawing can be another point against freezing food. Texture changes can sometimes be kept to a minimum when food is allowed to warm slowly within a refrigerator or when submersed in cool water. That sort of thing takes at least a few hours planning though. Not all of us are up to that every day of the week during the winter months. There are other options, but pulling chicken from the freezer and thawing it via a microwave not only guarantees that the texture will be off but also usually means portions of the chicken will be almost cooked while others remain cool when the microwave has done its thing. So time and forethought are all but required when thawing frozen food. Those can be precious commodities when everyone in a household works for a living or spends most of their day looking after young ones.

Most freezers are subject to available power. Ever have to sort through a half-thawed freezer a day or two after a power outage to find out what is still frozen and what isn’t? It is disgusting work, especially when meats are involved. Yuuuuuuuuuuuk! Throwing uncooked food out is also something that makes me rather sad. Maybe that response is a product of guilt trips like, “Look. There are people homeless and starving just a few blocks away. I scraped to put that on your plate. Eat it.” The sentiment remains, regardless.

Canning is the other option Kate and I usually discuss. I tend to like the idea of canned foods better. Cans or jars are easily stacked and can be stored almost anywhere in a home. The packaging is easily recyclable; especially since the recycling of aluminum and steel cans was one of the first widespread, modern home-waste recycling programs.

While cooking with frozen food (thawing, really) takes forethought and time a bit before the end product can be used, canning requires planning and research at the very beginning. Adjustments due to elevation must be made. Acidity must be judged. Different equipment and methods must be used. It can be complicated. But using canned goods to make a dinner when rushed? It couldn’t be much easier. Pop a lid or crank a can-opener and I’m on my way in just a few seconds.

Texture of food isn’t changed by the expansion and contraction of water crystals when canned. However, canning has a different change which counts against the process. Fruit and vegetable enzymes are suspended easily when frozen but not when canned. Heating the food becomes necessary for that purpose. So various fruits and vegetables can (heh) get fairly mushy in their little jars.

Blanching is the compromise. Squishy blanched and canned food still exists but usually only comes from the very bottom of a jar. Enzymes still do their thing too, though at a reduced rate. The end result is that the shelf life of blanched-then-canned foods isn’t nearly so long as foods which are frozen or cooked and then canned.

There are other points to do with home canning and freezing that I haven’t included and still others I likely haven’t thought of at all. Then there are commercial canned and frozen foods. What local, national, or global companies reliably buy good stock from good people? Which labels do I trust when I’m out of options or time and want a can or frozen package of peas from the corner market?

This is what really sparked the debate again this year and, subsequently, this post. I bought a completely tasteless can of peas and don’t want to repeat the experience. I thought of conducting a cute experiment; hypothesis, criteria, the works. My funds are a little too limited for that sort of thing though.

What are your thoughts, please? Do you tend to buy frozen or canned fruits and vegetables? What brands do you like or dislike? Do you freeze or can foods yourself? How do you preserve meats for you and/ or your family?

And the first person to mention a certain canned meat product, the name of which rhymes with lamb, will be taunted profusely. That stuff is nasty.

Sources for this post include Wikipedia, Home Canning dot com, and stuff left in my brain by my nurturing grandmother and several brave and inventive junior middle and high school general science, chemistry, and biology teachers. All rights reserved for making left turns. Spleen not included. Void where prohibited by common sense.