I am experiencing tomato overload. This is the weekend haul from three tomato plants, including the monster plant, which has been getting more pruning and staking. The varieties are amish paste, arkansas traveller and... one other that I forgot to mark when I put it in! I may never know. Out of curiousity, these tomatoes are quite delicious, yet they are lacking in the acidic punch I'm used to. Is that the variety or the growing conditions? How can I boost the acidity in the final product?