Today Elizabeth Andress answered my question a bit more indepth about the acid blend and in particular about malic acid. She said that someone had emailed her about it. She said she didn't know if that person was in the audience or not, so I did push the button on the box to tell her that I was. I really appreciated her addressing this question. She said that when acids are added there is a buffering that takes place. She said different amounts of the other acids would be needed due to the natural resistance of the foods being canned. So, there is no way to safely determine at home how much of the other acids would be needed in place of plain citric acid. She said that the acid will also change the water activity in canned foods. This is what I learned or at least made it more clear and seems more indepth, espcecially why some things need more acid when pickling than other foods. As acid is added to a food the pH decreases (becomes more acid). The speed and amount of pH change depends upon the acid added and the buffering capacity of the food. Most food acids such as citric acid or acetic acid are relatively weak acids. The buffering capacity of a food is its ability to resist changes in pH. Therefore, the amount of acid that must be added to a food to lower the pH is dependent upon the buffering capacity of the food. Foods high in protein such as meats have greater buffering capacity than vegetables. Meat will thus require greater amounts of acid to lower the pH to the same degree. Maturity and varietal differences affect the buffering capacity of vegetables. So, I did some good information from her. She seems to be such a kind, down to earth lady. I was so pleased to have been able to see her on the video conference today. I have some more information to share on other subjects from today.

Thanks - I figured the acid wouldn't be a problem. I guess I should have asked if there was something the acid was taking off the inside of the canners that would be a problem - aluminum oxide? Would that be like alum and make the beans crisper ;-)?

I might as well try this recipe .. thanks!

chas045, you are correct that measuring in oz may not have high enough resolution. It did occur to me that I should have set the scale to measure in grams. 1/100 of a gram is better than 1/100 of an oz. However, the visual inspection with the microscope convinced me that there was no corrosion on the aluminum. Optically, light wavelengths are not far from atom sizes. The change in light on a reflective surface can be effected by thickness of a few atoms. The anti-reflection coating on a camera lens makes the lens reflection bluish. A few atoms of oil (oil slick) on a puddle of water make the reflection of light in rainbow colors. The microscope inspection of the aluminum foil showed no difference at all on the tested surfaces. Like all metals, including stainless steel, can be subjected to corrosion when two dissimilar metals are in an electrolytic solution, depending on their respective locations on the Periodic Chart. That�s what happens a lot when you see discoloration or pitting on aluminum. It is a scientific mystery that, aluminum being the third most abundant substance on earth, our body has not developed much use for it. There are not too many aluminum compounds which are toxic to the body (as I remember), because of that, sometimes I think by reacting to impurities, aluminum can render some toxic substance harmless. dcarch