The canning process and the technology behind it provides some clues as to how to successfully design a process and a supporting system. It also illustrates the need for solution evangelization, too. When my mother was making jams and sauces in her 1960s kitchen, she used the inferior technology of paraffin wax to seal the jars. While no one got ill from this technology, throughout the years, the study of home food preservation systems has informed and changed the way the process is carried out. Not using wax today is well-known, but I still find it on the shelf in the store right next to the new, safer lids and bands.
Our relation to technology is mostly dependant on how we learned. We still find people today who prefer paper checks to move money, envelopes and stamps to communicate, and margarine for baking. In the latter case, we have gone from butter to margarine and now back to butter based on lobbying and the desire for a better solution. The definition of "better", of course, varies. About canning, recently Stephen Colbert cast aspersions while talking with Emily Matchar about her book Homeward Bound.
The Ball Blue Book Guide to Preserving is the architectural blueprint for home canning. Why is it more than a cookbook? It has recipes, but more importantly, it covers all 6 columns of the Zachman Framework:
- What - This is the recipies and the equipment.
- How - This is explored in-depth as canning has a very specific process model.
- Who - You, of course, but also the roles of the boiling water, the lids, the acid, the sugar, etc.
- Where - How you layout your tools and raw materials, including final storage is the "where" element.
- When - Timing is critical in canning and there are pages of timing models for each type of food.
- Why - There are many motivations like saving money, getting back to basics, or giving a gift.
"As heating begins, the contents of each jar expand, and changes in internal pressure take place. Initially, gases are vented from the jar. When the processing period is finished, the atmospheric pressure outside the jar is greater than the pressure inside. This difference in pressure pulls the lid down onto the jar and forms a vacuum seal."The process is the critical element here and it has been refined and documented so that anyone can have success. From not tightening the bands too much, the the water temperature, to your altitude, the "what", "how", and "when" are the focus columns in this system.
Enough of the justification . . . on to the fun! Read and view on to see how I turned 15 pounds of ripe tomatoes into 7 pints of crushed tomatoes in juice. These jars of summer will be great in December or March of next year flavoring pasta or caramelizing in a beef braise. The process begins as you pick the tomatoes, wash them and sort out the best ones.
I picked 27 pounds of tomatoes from a single plant (I'll get about 45 pounds total over the season) but in these videos I can about 15 pounds into just 7 pints.
You only need a very large pot, a knife, and the canning jars, but I have a few nice-to-have tools. But all in all they are not expensive. Check out my setup below!
You have to make sure to not re-use the canning lids as they need to be in pristine condition.
Once I have all of the stuff in place I can begin to peel, core, chop, mash and cook the tomatoes. For crushed tomatoes, you only really have to crush a few of them to get the juice going and then the heat does the rest of the job.
One of the processes you need to accomplish is peeling the tomatoes and the blanch / shock method is the best. To do this, you rapidly alter the temperature of the whole tomato so the skin splits and separates from the fruit. You cannot effectively peel a tomato like a pear, so this is one of the most import processes. Check it out here with the beginning and ending Glass button fumbling:
Finally, there is filling the jars, sealing them, and boiling them. I shot a few more videos and have toyed with mixing them together in a comprehensive video, but time is short and with all those ripening fruits, Glass and Leap to play with and Python to learn.
