[NAFEX] canning without a boiling water bath
Sam.Brungardt at state.mn.us
Mon Jan 5 16:17:28 EST 2004
While this short-cut method may work for fruit juices, tomatoes, and other acid foods, I would NOT consume the contents of any jar whose lid has lost the seal in long-term storage. Boiling or microwaving the contents of such a jar will kill any microorganisms present, but according to the Centers for Disease Control, it takes 10 minutes of boiling to destroy the botulin toxin that may have been produced.
I give many of the fruit products I put up as gifts, and giving someone a gift that would end up making them sick or worse would be some Gift (German for "poison") indeed. That's why I always process everything I can in a boiling water bath or pressure canner. The exception is fermented products (e.g., sauerkraut, brined pickles) which I store under refrigeration.
Not following USDA's safe canning guidelines just isn't worth the chance that someone might get sick. If, when I've processed a bath, a jar hasn't properly sealed, I refrigerate it and eat the contents as soon as possible. In storage, if I find that a jar is not well sealed or that its lid is bulging, I consider it of dubious wholesomeness and throw the contents out.
I've also had the purple-to-brown or red-to-dusky-pink change occur with a number of fruit juices and jellies that I did not get around to using fast enough. Maybe I'm too inclined to "eat with my eyes," but in general I feel that this deterioration is accompanied by some loss or change of flavor. -- Sam Brungardt, St. Paul, Minn.
On Jan. 5, 2004, Helene Dessurault wrote:
Date: Mon, 05 Jan 2004 10:43:45 -0600
From: HDessureault <inter.verbis at videotron.ca>
Subject: [NAFEX] canning
To: nafex at lists.ibiblio.org
Message-ID: <001b01c3d3ab$2bf8cd60$76db60cf at cicero>
Del, While it is true that this method of sealing jars is not as reliable as
the hot water processing bath, it is generally safe and good enough for
fruit juices, pickles, and all foods containing enough acids or salt to
prevent the development of dangerous bacterias.
(Of course, all foods with little acids or salt, all meat, fish ARE NOT SAFE
without using an adequate hot bath processing or a real canner.)
Nevertheless, for fruit juice, the following is usually suitable:
« When a sterile hot jar is filled with boiling hot juice and a sterile lid
is placed on it immediately, making sure that the rim is clean, and then a
screwed-on ring is fastened to keep the lid in place, the pressure in the
jar is more or less equal the pressure outside. As the liquid cools off the
pressure inside decreases and the pressure outside becomes greater keeping
the lid in place. » My understanding is that more reliable hot bath and
canner processing only serve to decrease further the pressure inside the
jar, thus the suction noice that you hear on opening a tighly seal jar. But
the easy method of processing without hot bath is pretty good for juices if
you keep them in a dark and cool place.
With this type of canning you can usually tell if the integrity of the juice
is compromised by checking the position of the lids periodically. If there
is the smallest bacterial activity in the jar, the pressure builds up INSIDE
the jar pushing the lid UP...
If you are concerned about the lids coming off more easily with this quicker
method, you can place the jars upside down for the first 1/2 hour on closing
the jar (until the pressure has become negative in the jar) before you turn
them in their upright position again to finish cooling. I think the weight
of the jar helps improving the seal but you have to make sure that the cap
is screwed on tight.
It also helps when all the jars and lids are very hot.
Inspecting your canned jars periodically to check the lid is also important.
All you have to do is put a slight finger pressure in the middle of the lid of
each jar to feel if there is any yield.... If so, move the jar to the fridge
and use it as soon as possible. If in doubt, you can always boil or zap the
content in the microwave, which is sure to kill any living organism, good or
bad. A security step useful when in doubt.... and a subject not very
politically correct in this day and age.
Back to my personal experience with this quick sealing method, it works very
well if you keep your jars under close supervision.
I was under a very tight schedule last Fall to make a lot of tomato sauce
before going on a trip and I used this method to process the large quantity
of jars and because I feel confident about my skills at canning. About a
month later when I came back, I had to move a couple of jars to the fridge,
whose lids were starting to slightly push up, which does not mean that it
did not still tasted fine, since it does not take very much to create
pressure in the jar. Tomato sauce is acidic and very safe and some jars
keeping only a month instead of a year is fine by me. It just means that
they are the first to be used.
On an even more personal note, recenty, I used a three year old jar of
blackberry juice (the seal was good, the taste was fine but the color was
slightly off, more brown and less purple). I poured it over a big lamb roast
during the last hour of cooking to make the most fabulous gravy you can
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