G'morning! They float when processed in Water Bath... there is just not as much head space (top + bottom) so it was not as noticeable. I never had any problems in the past using W/B process, but unfortunately now that many varieties of tomato's have lost their acidity through modern genetic tweaking and hybridizing it is now necessary to add acid to tomatoes, including heirloom varieties when canning them :-( The level of temperature needed to kill botulism bacteria for low-acid foods can only be reached by using a pressure canner. So, I bought a new pressure canner, and now I am going through the growing pains of learning how to use it. I am just above sea level, so I only used 10 psi to process. It is quite the learning curve - it was SO much easier 10 years ago! I've always wanted to try canning Salmon though so now that I've invested in the proper equipment, that will be my next project :-) I did notice the interior of the canner was shiny ... I added a tbsp of vinegar to the water as suggested in the manual but I guess it was the lemon juice? Since I was having so much trouble getting the pressure up (took WAY 2 long on my stove), I've now invested in an outdoor cooking burner so when I get a chance I will try another batch of tomatoes and see if that improves the final outcome. I will also try using citric acid instead of lemon juice because I have a feeling I am not going to like the flavor in a few months once that lemon juice settles in :-( I was trying to avoid doing a hot pack - it is just one more step that makes it a longer process :-( I am almost at the point that I want to freeze them in the future ... seems like a LOT less trouble! I will persist tho - because I have invested 2 much time and $ 2 give up now :-) Thx again for all of your help and suggestions - I really appreciate it! :-) Have a gr8 day!

Thanks, TomNJ, for the backup info supporting your suggestion that the long cooldown is due to a vacuum. I think you've found my culprit in the AA instruction manual section you quoted. I've just re-read my manual and found the same quote. Equally important, I believe I've found my principal error that led to the vacuum-forming: subjectivity. In my first posting (Sept 1), posing the long cooldown problem, I explained that I left the weight on well after the gauge read zero pressure because I heard hissing when I slightly lifted the weight. My thinking was that I shouldn't fully remove the weight if I still heard hissing when I slightly lifted it -- that I should wait until there was no hissing. Dave's first post said "it is also normal for a small amount of steam hiss - very brief - when the weight is removed". Since I felt I had a long hiss (several seconds, pffffffffffffffffffffffffffffffffffffffffffffffffffffff) vs pffft) I thought what I had was abnormal. What I'm now thinking is that my hissing was just normal and I should have removed the weight, waited 10 minutes before removing the lid, and all would have been fine (no vacuum, no long cooldown). So that's what I'll try the next time, but just canning some colored water in a test like linda_lou first suggested in her Sept 2 posting. Thanks to all of you for your concerns about the health risks of leaving the jars in the canner for several hours. I think Dave was wrong, though, in saying "warnings about the hazards of that were given early on yet were repeated". The warning was only mentioned once by linda_lou before my Sept 2 canning, and it so happens I didn't get her message until after my Sept 2 canning. I haven't done further canning after reading her message, which was subsequently backed up by others. Similarly, I didn't read linda_lou's recommendation to test with water rather than food until after my Sept 2 canning. I haven't done further canning after reading her message, which was subsequently backed up by others. I'm grateful for the suggestion to test with water before risking food and health. I'm unhappy that such a suggestion isn't in the owner manual, but I can't blame anyone here for that. I'm sad that a respected poster thinks I ignored warnings repeatedly (and said so to the world). I'm crying at the thought that my food might be dangerous to eat, given how much love and effort I put into growing and canning it. Such is life. Tea time. ...Terry

Dare I say something in defense about a steam canner? I have used one for many years now and it uses about the same amount of water a pressure canner uses. It has proven it worth here by giving me many canned items that are not overcooked. I especially like it for jellies and pickles. Neither are difficult to can, or process. Because I add extra acid to both, safety issues are not a big concern. I had done many temperature tests on these, and have found that the recovery temps are quite fast, when it comes to the canning water coming to a boil again. As everyone knows, heat rises, cold drops. With room temp, water filled jars inside, and the canner water previously boiling, it can take at least 10-15 minutes for the canner to reach boiling again, even though the jars are not even touching the water. Also, the measurements I did were done with thermocouples and a device that is able to chart out 6 locations within an area. These temperature measuring devices are very accurate and when I had jars filled with water only, and measured the internal temps, they came up faster in heat than a boiling water bath. I am not saying a pressure canner is in the same class, as it is not. Pressure canners are used for low acid foods and offer higher processing temps above 212 degrees of boiling water. This is the reason for the high pressure used in a PC. The steam canner has a slight pressure when boiling, as it jets out a strong steam from just two tiny holes down near the water level. This indicates to me that the jars inside, are in fact exposed to something that is at least 212 and is under slight pressure. I measured an internal temp of 212 degrees inside a water filled canning jar after 10 minutes. That jar was filled with boiling water prior to the test however. I would never consider using this canner for any low acid products. For pickles, I prefer full 5% strength vinegar too. The jellies get an added acid blend of malic, tarteric, and citric acid.

If you really want to test the seal, whether BWB or PC, then after the jar is fully cooled (12-24 hours), remove the ring and turn it upside down over a deep bowl. If the lid stays on, believe me, it is sealed and you don't have to worry about it. The whole point of pressure canning is that the product reaches a temperature that will assuredly kill any nasties (assuming you follow recommended time and pressure). There just are no bacteria. Consider this excerpt from FDA Consumer, 1990: The steamboat Bertrand was heavily laden with provisions when it set out on the Missouri River in 1865, destined for the gold mining camps in Fort Benton, Mont. The boat snagged and swamped under the weight, sinking to the bottom of the river. It was found a century later, under 30 feet of silt a little north of Omaha, Neb. Among the canned food items retrieved from the Bertrand in 1968 were brandied peaches, oysters, plum tomatoes, honey, and mixed vegetables. In 1974, chemists at the National Food Processors Association (NFPA) analyzed the products for bacterial contamination and nutrient value. Although the food had lost its fresh smell and appearance, the NFPA chemists detected no microbial growth and determined that the foods were as safe to eat as they had been when canned more than 100 years earlier. The nutrient values varied depending upon the product and nutrient. NFPA chemists Janet Dudek and Edgar Elkins report that significant amounts of vitamins C and A were lost. But protein levels remained high, and all calcium values "were comparable to today's products." NFPA chemists also analyzed a 40-year-old can of corn found in the basement of a home in California. Again, the canning process had kept the corn safe from contaminants and from much nutrient loss. In addition, Dudek says, the kernels looked and smelled like recently canned corn. In 1967 my DH was eating canned C-rations from 1944. Actually, he thought those meals were much better than the "modern" freeze-dried LRPs. Now I don't have any plans to eat 40-year-old corn and I won't live long enough for anything that might sit on my shelf 100 years, but the point is, properly preserved, food lasts well beyond any point of our concern. It may lose color, it may soften, it may not taste as good, but it is safe. Carol