Why does U of M tell you to process canned goods so long?

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BAPyessir6

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According to this article: https://extension.umn.edu/preserving-and-preparing/canning-quick-reference-chart

The chart shows that high acid, water canned foods (1 pint or 2 cup jars) need to be processed anywhere from 20-40 minutes. Isn't this very long for jammed goods? I've processed my jam this long before and had my peach jam boil out of the jar. What do the rest of you think?

Also another question, growing up, my mom always processed quart salsa jars in her canner, rhubarb jam half pints, etc. and had the water level One Inch From the top of the jars. Is submerging the jars instead really that much better? Her jars always sealed fine, so I always figured submerging the jars could make them waterlogged. What say ya'll?
 
Water level in canners. In a waterbath canner the water level is 1-2 inches above the jar lids. In a pressure canner the water level is usually below the level of the lids. A pressure canner that can hold 7 qt jars will have water well below the jar lids and if using 1/2 pint or pint, then even closer to the lids but below them.

Why must the waterbath canner water level be above the jars? That is the standard method and the tested method. If you are going to use recipes, it's just safer to do it following the stand methods.

The link talks about all kinds of canning in general especially times for WB canning for fruit/berries/halves/diced but not jam or jelly. Jam or jelly will be less (5-10 minute). I don't see any good jam or jelly recipes for canning on U of Michigan. You can use any of the University extension services or NCFPH for jam or jelly recipes. https://nchfp.uga.edu/how/make-jam-jelly#gsc.tab=0

Do my jams or jellies over flow, no, but my apple sauce and pear sauce do making the jars sticky on the outside.

Some people would rather pressure can jams/jellies/tomato products, and there is usually a way to do the canning in either the water bath canner or the pressure canner.
 
Water bath canning of jams and jellies is rather new and IMO unnecessary.

We used to ladle hot jam or jelly into hot sterilized jars and top them with a thin layer of melted paraffin.

1715631072278.jpeg


Paraffin sealed jams and jellies are no longer allowed at the New York State fair amateur food competitions.

For safety sake it’s probably best to follow the instructions from a reputable source.

Times change.
 
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The weird thing to me is how variable the amount of acid is, (I guess recipes differ) but many people I know who can salsa (I love salsa but I don't have a garden where I live so I haven't canned it myself yet) all have "botulism safe" salsa recipes. My sister does 1/2 cup vinegar per pint of salsa, my neighbor does 1/4 vinegar per pint of salsa, a few recipes online do 1/8 cup per pint, and my mom (she said she got it from a Ball magazine back in the 90s) does 1/16 cup vinegar per quart. Is this just to taste, as every palette is different? I figured since botulism was so scary there would be like a "standard" amount you should add. Except for a ph strip, I figure it'd be hard to know exactly what the PH of your salsa is when you can, so it makes me confused as to why so many variations exist. Or does this just take into account the amount of other ingredients (peppers, onions etc. and also sugar) you add?
 
According to this article: https://extension.umn.edu/preserving-and-preparing/canning-quick-reference-chart

The chart shows that high acid, water canned foods (1 pint or 2 cup jars) need to be processed anywhere from 20-40 minutes. Isn't this very long for jammed goods? I've processed my jam this long before and had my peach jam boil out of the jar. What do the rest of you think?
I think it's important to follow the instructions from the Cooperative Extension office for your area, which this is. Scientific knowledge and other variables change over time. For example, lots of tomatoes are less acidic than they used to be, so you might need to add more vinegar or citrus juice to ensure safety.

Also another question, growing up, my mom always processed quart salsa jars in her canner, rhubarb jam half pints, etc. and had the water level One Inch From the top of the jars. Is submerging the jars instead really that much better? Her jars always sealed fine, so I always figured submerging the jars could make them waterlogged. What say ya'll?
There are three considerations to proper canning: getting all the air out of the jars, sealing the lids and sterilizing the contents (or creating an acidic enough environment). Water from the canner should not be getting into the jars at all.
 
The weird thing to me is how variable the amount of acid is, (I guess recipes differ) but many people I know who can salsa (I love salsa but I don't have a garden where I live so I haven't canned it myself yet) all have "botulism safe" salsa recipes. My sister does 1/2 cup vinegar per pint of salsa, my neighbor does 1/4 vinegar per pint of salsa, a few recipes online do 1/8 cup per pint, and my mom (she said she got it from a Ball magazine back in the 90s) does 1/16 cup vinegar per quart. Is this just to taste, as every palette is different?
As I mentioned above, the guidelines change over time. I imagine your sister, your neighbor and your mom use the amount that was recommended when they started canning and they just continue to use the same recipes they always have, even though the guidelines have changed.

Or does this just take into account the amount of other ingredients (peppers, onions etc. and also sugar) you add?
Yes, the amount of low-acid ingredients affects the canning time and the rest of the recipe. The recommended recipes are tested as they're given, so unless you're very sure of what you're doing, it's not a good idea to change the ingredients.
 
If you want to follow recipes from safe sources like
or university extensions or ball or
then there is a huge facebook group Canning and Preserving with Love. They only recommend these methods.

If you want to follow recipe that the above group may not agree with, there is a facebook group called Canning Rebels Public. There you will find traditional canning methods that aren't approved by the authorities.
 
The weird thing to me is how variable the amount of acid is, (I guess recipes differ) but many people I know who can salsa (I love salsa but I don't have a garden where I live so I haven't canned it myself yet) all have "botulism safe" salsa recipes. My sister does 1/2 cup vinegar per pint of salsa, my neighbor does 1/4 vinegar per pint of salsa, a few recipes online do 1/8 cup per pint, and my mom (she said she got it from a Ball magazine back in the 90s) does 1/16 cup vinegar per quart. Is this just to taste, as every palette is different? I figured since botulism was so scary there would be like a "standard" amount you should add. Except for a ph strip, I figure it'd be hard to know exactly what the PH of your salsa is when you can, so it makes me confused as to why so many variations exist. Or does this just take into account the amount of other ingredients (peppers, onions etc. and also sugar) you add?
From what I've read, tomatoes used to be more acidic but now we have many tomatoes that aren't as acidic as they used to be.
Plus some canners have never used 'safe' recipes and they keep using them. So for taste without regard for safety, there are dozens of recipes with differing amounts of vinegar. Vinegar may be 4% or 5% or 7%, the safe recipes require the 5% acetic acid vinegar. And yes the safe recipes do mention if you can or cannot substitute ingredients (peppers, onions....) and by how much you can substitute them. For salsa sugar is never required it is always optional, that is spelled out in the canning general rules. Salt is also always optional in salsa. I hope that helps.
 
If you want to follow recipes from safe sources like
or university extensions or ball or
Just to clarify, the National Center for Home Food Preservation linked above is the extension office of the University of Georgia. It's the primary location where the actual testing for canning and other preservation methods takes place, so the information on other university extension sites usually comes from there. Sometimes other universities might do their own research for things like canning at altitude, since that makes a difference in the method. But in general, the NCHFP will have the latest, most up-to-date research-based recommendations.

then there is a huge facebook group Canning and Preserving with Love. They only recommend these methods.
I've been following one called Food in Jars for over 10 years. They also go by the USDA guidelines. Just one more option :)
 

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