I just completed the MFP course, and I have one nagging question that I have been unable to find an answer for; What is the actual acidity level of bottled lemon juice, and can I use any brand of bottled lemon juice in a canning recipe at the recommended level? I do not wish to use Realemon brand, or similar brands of lemon juice (the ones that are typically recommended for canning) because they include ingredients I would prefer not to consume. I found a few organic options, including Santa Cruz Organic Lemon Juice, and an internet search brought me to the Extension website where, on August 31, 2015, Jeanne B. stated that all bottled lemon juice is manufactured to the same acidity standard, and was therefor acceptable to use for canning. Nowhere can I find % acidity statements for any bottled citrus juice product, except one: Lakewood Organic Bottled Lemon Juice, which states that the acidity is 5%. Further internet searches, in trying to find the acidity levels of bottled lemon juice, lead me to all sorts of food preservation sites, with most agreeing that bottled lemon juice varies greatly but is at least 4.5% to 5% acidity. I was taught, in the MFP program, that if I don't have bottled lemon juice I can substitute vinegar (5% acidity) at a 2:1 ratio (vinegar : BLJ). But they appear to have the same % acidity. Doubling the vinegar would not make a palatable fruit product. Please offer some clarification.