Your link only takes one to the full guide not the recipe you have in mind. USDA Guide to Home Canning is from NCHFP and all the same recipes are directly available on the NCHFP website - one with meat, one without. http://nchfp.uga.edu/how/can3_tomato.html So which are you talking about?

So commercial canned tomatoes or home canned ones? Recanning commercially canned foods isn't recommended simply because the double processing really affects the texture and taste, plus it wastes energy. But there are no real safety issues with doing it.

Commercially canned tomatoes include added citric acid and sometimes other preservatives which most prefer to leave out of their home canned foods. But it is your choice.

As to amount, that all depends on the size cans used. Commercial cans provide their weight on the label but much of it is water so once you calculate the number needed based on brand and can size, add a couple more to cover for that water weight you will be draining off before use.

If using previously home canned tomatoes then a pint roughly equals 1 pound.

But a word of caution - you don't even know if you will like this recipe so why make a full batch of an unknown? Divide the recipe and make a 1/2 batch or even a 1/4 batch first to determine if the end product is acceptable to you rather than wasting all the ingredients only to discover you don't like it.

Dave

I was talking about the spaghetti sauce without the meat. Thanks for the info and Will try half the 1st time. Thanks for always being so helpful! It's appreciated!

I make both of their spaghetti sauce recipes, they are great. They are plain, fresh sauces.

The second time you make it, you may wish to kick up the dry herbs in it a bit, depending on your audience's tastes.

I agree with Dave's estimates. "If using previously home canned tomatoes then a pint roughly equals 1 pound." The NCHFP says "22 lbs fresh tomatoes yields 7 quarts" (http://nchfp.uga.edu/how/can_03/tomato_crushed.html) but I would have said that 30 lbs gave you 15 US quarts of canned, crushed. They probably core and seed more religiously and so have more discard during prep.

Thank you for that info. It's very useful.