Canning Tomatoes The juicer spits out the skins, along with most of the seeds... all of which will go into the compost bin. As the sauce heats up and starts to boll, there will be what is referred to as "spume" on the top... you'll want to remove the majority of that simply by skimming the top with a spoon. I like to run my jars through the dishwasher on a short cycle, even if they're already clean, and I leave them in there to keep them hot. I pull one jar at a time, and add one tablespoon of lemon juice, and one teaspoon of salt. I prefer using sea salt... it isn't quite as salty as the iodized salt, and it's better for you. NEXT