What is the source of the recipe Kerry? That info will help determine the safety of most any canning recipe since there are many unsafe sources out on the web and in books.

Most tomato jam recipes are ok because they require the addition of extra acids, in this case the lime juice. This particular recipe is probably safe but with untested, unapproved recipes there is always a bit of doubt and no guarantees.

I linked one of the approved recipe for tomato jam below. There is another good one in the Ball Blue Book.

Dave

Here is a link that might be useful: NCHFP - Tomato Jam

Thanks Dave, I'll look at those.

http://www.foodinjars.com/2010/09/tomato-jam/

Usually if you use the forum search bar at the bottom of the front page you can type in the website in question and find previous comments about it. I know that foodinjars.com has been discussed here in the past but I don't recall exactly what was said about it other than it is just a personal blog and the author lists no canning training or food science credentials at all.

Meanwhile the long discussion about safe sources that I linked below is well worth reading.

Dave

Here is a link that might be useful: Is anyone else getting concerned?

Interesting discussion. I read recipes from a variety of sources, and am not limited to the official tested sources. However, if I see something that looks interesting, I always compare it carefully to a comparable recipe from a tested source -- for acidity, proportions, processing method and time etc. Many of my family recipes were not up to snuff, but were easily enough adapted so that I'm confident they're now safe. If I'm not sure, I don't make it.

For all of the canned goods I give away, I'm very leery of stuff that is given to me. If I don't know that the person is up to speed on safe canning basics in the 21st century, I say thanks, put the product on the compost pile, and clean and return the jar.

I know this is an old thread, but I had a question about this recipe as well and didn't find anything in the search. I was wondering why her processing time would be twenty minutes for a jam. I know she adds ginger to it, but I don't see how processing longer in a BWB would make any difference to a low acid vegetable. I'm an MFP, so not new to canning, but I just can't figure out how she came up with the processing time :)
Also, I've adapted it to fit more with the SETP spiced tomato jam recipe because my friends LOVE it but it takes FOREVER and so I decided to do it with pectin. Not exactly the same flavor, obviously, but good enough. At least for new friends who didn't taste the original :)
Thanks!

I was wondering why her processing time would be twenty minutes for a jam.

Good question but unfortunately one only the recipe author can answer.

I can only speculate that since the author knew it was an untested recipe and so had no insurance that it was acidifed enough she decided to add additional processing time mistakenly assuming that would cover any "iffyness" in the recipe.

But that's just speculation. When using untested, unapproved recipes that is about all we can do.

Dave

8 tablespoons of lime juice is equivalent to 1/2 cup, which will safely acidify 4 1/2 lbs. (approx.) of tomatoes yielding 6 cups of prepped product, so it wouldn't take much to modify this recipe to the NCHFP equivalent and be assured of safety.

If you're uncomfortable with the grated fresh ginger, place it in a bouquet garni bag and cook it with the preserves then remove before bottling.

For another comparison, the Ball Red Tomato Jam calls for 1 tsp. lemon peel and 2 tsp. lemon juice for 6 pounds of tomatoes, which would seem to indicate the 1/2 cup of lime juice in the posted recipe is more than sufficient, even allowing for the bit of ginger.

The 20 minutes' processing time I do not understand. The NCHFP time for tomato jam is the standard 10 minutes. But in the latest edition of the BBB, I have seen some preserve recipes which call for 20 minutes. I have no idea of the reason, and for their tomato jam the time is still the standard 10 minutes.

Carol

Thanks Carol and Dave! I'm not worried about the safety of the recipe, but that's a good idea for future reference about removing the ginger after cooking with it.
The tomato jam recipe in SETP calls for 5 minutes. I'm using their measurements for 3 cups prepared tomatoes, 4 1/2 cups of sugar, and one box of pectin. I'm using her spices, plus the ginger, and lime juice for the acidity. She calls for a half cup of lime juice, SETP calls for 1/4 cup lemon juice and a little rind - I'm doing 1/3 cup of lime juice. I'm processing ten minutes even though I imagine 5 minutes would be fine lol. Tastes great and is gelling well. Thanks again!

5 minutes is standard for sterilized jars, 10 minutes for hot clean but not necessarily sterilized.

Most of us process for 10 minutes because it's easier than sterilizing everything. The total time is no more than sterilizing and canning for the shorter time and the longer processing time produces a more reliable seal (in my experience).

The only time I process for 5 minutes is with a delicate no-commercial-pectin jelly. Longer processing on something like that can break the pectin bond.

Carol

I know this is a very old post, but what is SETP?

canning book. So Easy To Preserve.

Thanks! I was wracking my brain trying to figure it out! :)